Commonwealth Fusion Systems (CFS) is building the SPARC tokamak in Devens, MA, USA, with first plasma planned in 2026. The initial objective of SPARC will be scientific demonstration of Q>1 (net fusion energy) in a tokamak, with experiments then shifting to the goal of exploring operating regimes for ARC, the first fusion power plant. SPARC utilizes a high field, compact, pulsed tokamak design...
Six longitudinal gradient dipole magnets (DLGs) are used in every standard arc of the storage ring at Wuhan Advanced Light Source to reduce the beam emittance. Each DLG is made of 5 permanent magnetic units, providing the transverse filed gradient by tilting the polar faces and the longitudinal gradients simultaneously The field designs, assembly, and detailed magnetic measurement of the DLG1...
A compact synchrotron based on superconducting magnets is under development in China. The compact synchrotron, with a circumference not exceeding 35 meters, is equipped with eight superconducting dipole magnets. It is designed to accelerate multiple types of heavy-ion beams from 7 MeV/u to 430 MeV/u. The Discrete-Cosine-Theta (DCT) coil structure is used to reduce the magnet size. The central...
The US Magnet Development Program is leading the ambitious challenge of developing an accelerator dipole magnet targeting a bore field of 20 T. Among the explored designs is a 6-layer, cos-theta hybrid magnet, which includes low-temperature superconductor (LTS) and high-temperature superconductor (HTS) coils powered in series. The objective is to build a 1 m long demonstrator magnet with...
In older to explore charm physics and tau physics in next decades, a third-generation circular electron-positron collider Super Tau-Charm Facility (STCF) with the energy range of 2-7 GeV is being developed and pre-studied in University of Science and Technology of China. As the last correction of the particles before the collision, the superconducting magnets in the interaction region (IR)...
Within the framework of the International Muon Collider Collaboration (IMCC), researchers are involved in a feasibility study to develop high-temperature superconducting (HTS) magnets for the proposed 10 km collider ring, designed to reach a 10 TeV center-of-mass energy. Due to the short lifetime of muons of only 2.2 µs, the machine must minimize the acceleration time of the particles allowing...
An International Muon Collider Collaboration (IMCC) has been formed following the recommendation of the Updated European Strategy for Particle Physics (ESPPU) to study the feasibility of a 10 TeV muon collider within a compact 10 km ring. This machine combines the precision of lepton colliders with the energy reach and discovery potential of hadron colliders, overcoming synchrotron radiation...
Within the framework of the International Muon Collider Collaboration (IMCC), a feasibility study is underway to develop the proposed 10 km collider ring, aimed at achieving a center-of-mass energy of 10 TeV. The stringent requirements to maximize luminosity and shield decay products of muons - characterized by only 2.2 μs lifetime at rest - necessitate the design of compact, high-field, and...
Next-generation particle accelerators require the development of high-field bending dipoles to enable precise beam control and enhance operational efficiency. $Nb_3Sn$ has emerged as a promising superconducting material, already proven in accelerator magnets like the MQXF quadrupoles for the high-luminosity upgrade of the LHC. In partnership with CERN, the INFN divisions in Genoa and Milan are...
The Falcon Dipole is a project led by the Italian Institute of Nuclear Physics (INFN) which aims to fabricate a 12 T short model of a Nb3Sn cos-theta accelerator dipole as part of the High Field Magnet (HFM) R&D program at CERN. The status of the project is at the fabrication step of the first dummy coil in the industry and, in this paper, we present the results of the first campaign of...
The large-scale design and manufacture of HTS magnets will require the production and use of thousands of kilometres of HTS tape, supplied by various manufacturers worldwide. A critical step in enabling the production of these magnets is establishing a robust quality control (QC) procedure that can be consistently applied to all received batches of HTS tape before their use in Tokamak Energy’s...
High-temperature superconducting coated conductors (HTS CCs) are essential components in advanced technologies such as high-field magnet, fusion, power transmission, and medical imaging. However, non-uniform thickness along their length and width can severely affect the performance of HTS magnets. Despite the importance of maintaining thickness uniformity, no system currently exists to...
The effect of pinning landscape on critical current in percolative HTS composites is studied. The superconductor contains percolative superconducting cluster carrying a transport current, and artificial pinning centers created by normal-phase fractal clusters. Such a structure provides for effective pinning and thereby raises the critical current because the magnetic flux is locked in finite...
We have fabricated GdBa2Cu3O7-δ (Gd123) thin films doped Gd2CuO4 (Gd214) as artificial pins on LaAlO3 single crystal substrate by fluorine-free metal organic decomposition method and investigated their crystallinity and magnetic field angle dependence of JC-B properties. Recently, we have succeeded in fabricating Gd123 crystals introduced Gd214 as effective artificial pinning centers. TEM...
High $J_c$ in Bi-2212 wires is crucial for their use in high-field magnets. $CO_2$ and $H_2O$, which can inadvertently be incorporated into Bi-2212 wire, negatively impacts $J_c$. At room temperature before the heat treatment, $CO_2$ and $H_2O$ are present in the wires as carbonates, hydrates, or surface adsorbates, but during the overpressure heat treatment they become gases. The...
Bi2Sr2CaCu2O8+x (Bi-2212) material, the only high-temperature superconducting material capable of being fabricated into isotropic round wires, holds significant potential for the future manufacturing of high-field magnets. In coil design and fabrication, the selection of coil radius is crucial, as an excessively small radius can substantially reduce the coil's current-carrying capacity. This...
High-temperature superconducting (HTS) magnets are essential for advanced technological applications but are susceptible to performance degradation under extreme environmental conditions, including irradiation and thermal variations. While extensive research has focused on the effects of irradiation on HTS materials, the mechanisms by which temperature influences their irradiation response...
High-temperature superconductor (HTS) cables have a broad prospect in power transmission applications due to their low loss and high current capacity. The stacked-tape cable is a type of HTS cables wound with parallel-stacked tapes, which shows enhanced thermal stability due to electrical and thermal contacts between tapes. During local quench, the transport current is redistributed among...
Bi-2212 is a promising high-temperature superconductor (HTS) for ultra-high field magnet applications, owing to its exceptional current-carrying capacity under high magnetic fields, good mechanical stability, and unique isotropic round wire structure. The Northwest Institute for Nonferrous Metal Research (NIN) has been actively engaged in advancing the performance and industrial development of...
The Cable-in-Conduit Conductor (CICC) is one of the core components in large-scale superconducting (SC) magnet systems, characterized by its multidisciplinary and technically complex nature. This paper investigated and developed a rectangular Bi2212 CICC to withstand high magnetic pressures in the CHMFL. Detailed analyses of its mechanical, stability, fabrication, and preliminary tests are...
Understanding quench dynamics in high-temperature superconducting (HTS) conductors is pivotal for their reliable integration into next-generation superconducting magnets. In this work, we present electrical and thermal simulations of Bi-2212 conductors during a current ramp to thermal runaway quench and compare them with test results. Bi-2212 conductors analyzed include a single round-strand...
In fusion devices, superconducting magnets are subjected to the combined effects of magnetic fields, temperature gradients, and mechanical stresses during operation, resulting in significant stress on the conductors. These conductors require high critical currents, low AC losses, and high mechanical strength. We have designed a novel tenon-mortise modularized conductor (TMMC) and studied the...
Evaluation of AC loss is a key issue for high temperature superconducting (HTS) conductor design and optimization, which is critical for the efficient operation of large HTS devices. our research group previously presented a novel HTS conductor named Tenon-Mortise Modularized Conductor (TMMC), composed of multi-layer concentric round sub-conductors arranged in a fully-misaligned configuration....
Due to the rapid development of compact nuclear fusion devices, the industrialization of second-generation high-temperature superconducting tapes (2G-HTS) have entered a new historical phase. SuperMag Technology (Shanghai) Ltd, a spin-off from Shanghai Jiao Tong University, has swiftly established at the end of 2022 as an manufacturer dedicated to cost-effective 2G-HTS tapes. After two years...
Electric Vertical Takeoff and Landing (eVTOL) aircraft is attracted as a new means of transportation. The vertical takeoff consumes much amount of energy, leading the limitation of range and payload. To address this problem, we proposed a new method of takeoff by using a launch system for eVTOL with fixed wings. The eVTOL is accelerated by a linear motor mounted on the system. When the eVTOL...
Naval minesweeping is a crucial initial operation in naval warfare, ensuring safe passage for friendly forces by clearing sea lanes of mines deployed by adversaries. Current minesweeping methods utilize permanent magnets or copper cables to trigger magnetic mines. Generating stronger magnetic fields enables the clearance of deeply laid mines and the replication of larger vessels' signatures....
Aluminum die-casting requires an efficient melting technology to conserve energy, because aluminum die-casting process produces a large amount of aluminum casts and consumes huge quantity of energy. We have suggested the possibility of supplying molten aluminum to the die-cast process in a short time by DC induction heating using a superconducting magnet. In our DC induction heating equipment,...
Electromagnetic forming (EMF) is a significant application direction of pulsed high magnetic fields. As a high-speed forming technique, EMF offers typical advantages associated with high forming rates, such as enhancing the material forming limit, suppressing wrinkling and springback. Additionally, the driving force in EMF is a non-contact force, eliminating the need for a force transmission...
Bi-2212 round wire offers advantages in low screening current due to its filament structure compared to REBCO tapes among high-temperature superconductors (HTS). Additionally, established methods for creating superconducting joints are well known for Bi-2212. These characteristics have led to extensive research into its use in nuclear magnetic resonance (NMR) magnets, which require high...
Hot-dip galvanizing is a widely used method for protecting steel workpieces from corrosion, and controlling the coating thickness through wiping is crucial for ensuring both product quality and performance. Traditional gas wiping technology, though widely used, faces challenges, including air pollution, coating oxidation, uneven coating distribution, and difficulties in precise thickness...
The no-insulation (NI) technique has been widely used in the development of high temperature superconducting (HTS) magnets. The compact 23 T NI-HTS magnet consists of pocket-sized double pancake coils was developed and reported. Therefore, it has been demonstrated that NI HTS coils are suitable not only for large-scale, high-field applications but also for small-scale, high-field applications....
Electromagnetic forming (EMF), a critical application of pulsed magnetic field technology, is extensively utilized in manufacturing lightweight automotive components and high-precision aerospace structures. The process involves rapidly discharging high-energy pulsed currents from a capacitor bank into a coil, generating a transient, intense magnetic field. When a conductive workpiece is placed...
High-temperature superconducting (HTS) Maglev trains are gaining attention as a next-generation transportation technology due to their high efficiency and ultra-high-speed capabilities. However, losses occurring during operation significantly impact system stability and the maintenance of the target magnetic field. In particular, in PCS (Persistent Current Switch)-based HTS Maglev trains,...
Fully superconducting synchronous motors have great potential to achieve a high-power density (kW/kg), which is very attractive technology for future electric propulsion systems for aircraft applications. This system is expected to be operated with low voltage (several kV) and large current (several hundred A or more). Hence, the armature coil is required to have a large current capacity. In...
High-temperature superconducting (HTS) synchronous condensers have demonstrated exceptional potential in enhancing grid stability and providing rotational inertia, particularly in power systems with a high proportion of renewable energy. By incorporating HTS magnets into rotor systems, these devices improve dynamic support performance, reactive power regulation, and grid inertia, addressing...
The regular partitioned stator flux-switching permanent magnet (PS-FSPM) machine integrates both permanent magnets (PMs) and armature windings within a single stator, providing significant space utilization for both the inner and outer stators. However, the PMs on the inner stator limits torque enhancement to adjustments in the pole arc coefficient. To overcome this limitation, a PS-FSPM...
Permanent magnet motors use rare earth permanent magnets that are sintered light rare earth elements (Nd, etc.), heavy rare earth elements (Dy, Tb, etc.), and iron. Currently, since heavy rare earth element imports depend entirely on specific countries, high-performance permanent magnets that exclude heavy rare earth elements have been developed in order to stabilize the domestic supply chain....
Magnetic gears have the advantages of overload protection, no lubrication, fixed transmission ratio, and have broad application prospects in the field of low-speed and high-torque transmission. They can be used for motors, hydro-wind power generation, space gravity-free transmission, etc. Magnetic gears not only have research value for electrical disciplines, but also open up new ideas in...
The rotors of conventional rotor flux switching permanent magnet (R-FSPM) motor are all fractured and require non-magnetic materials for support to avoid the permanent magnetic field being closed in the rotor, which will reduce the mechanical robustness of the rotor. In order to overcome the above limitations, a V-shaped combination of magnetic poles rotor permanent magnet flux-switching...
A crucial aspect of electric aircraft propulsion is the development of higher power density motors and generators. One promising approach to achieving this is using cryogenic flow cooling, which reduces the weight and losses in conductors in motors. The resistivity of aluminum decreases significantly with lower temperatures, dropping by a factor of 10 from room temperature to 77.2 K (liquid...
With the rapid development of superconducting technology, the application scenarios for high-temperature superconducting (HTS) cables continue to expand, leading to increasingly complex configurations for cable installation. The thermal characterization of CORC cables is essential to ensure the stable and safe operation, making it an inevitable part of the design process of CORC cables. Due to...
Liquid Hydrogen and Superconducting Magnetic Energy Storage (LIQHYSMES) system based on electric-hydrogen conversion and superconducting magnetic energy storage is one of the important development directions of composite energy storage technology. As an important electromagnetic energy storage unit of the system, the thermal stability of LIQHYSMES magnet is crucial for the safe operation of...
Vector magnet technology is being developed at the Wuhan National High Magnetic Field Center (WHMFC). Vector magnets can generate magnetic fields at arbitrary angles to meet user-specific requirements, offering significant potential in fields such as topological states and electron spin manipulation. This paper presents a mathematical model for designing compact vector magnet coils. The model...
High-temperature superconducting (HTS) closed-loop magnet composed of gourd-shaped RE-Ba-Cu-O (REBCO, RE is rare earth) plates is potential for persistent current mode (PCM) with magnetic flux amplification and accumulation under field-cooling magnetization. Preliminary experiments and simulations confirm that the configuration can trap substantial magnetic fields, potentially exceeding 20 T...
The complex electromagnetic and structural response of pulsed septum electromagnets is currently being studied, aiming to reveal insights in the prediction of their life cycles. The fault prediction remains a key challenge, requiring efforts in modelling and onsite instrumentation. Recently, a high-fidelity numerical model was developed, which allowed us to deepen our understanding of the...
In this work, we developed an entire damage detection procedure, including the four-probe method, 2D-Hall scan method, magneto-optic method, and nano-CT method. The procedure can help us find the exact damaged area with a special resolution of 0.5 m and non-destructively investigate the microstructure in three dimensions. Combined with destructive characterization methods such as SEM, we can...
As HTS(high-temperature superconducting) cables emerge as a potential alternative to drive inno- vation in the power sector, we are building equipment that can produce various types of cables. In particular, as research on various types of conductors using REBCO based tape-type superconduc- tors becomes more active, we are manufacturing equipment that can produce cables with twisted and...
As interest in and the need for advancements in high-field technology grow, the development of superconducting cables capable of stably carrying high currents in the range of tens to hundreds of kA has become increasingly important. Stacking REBCO tapes can meet the high current demands of those systems while maximizing space efficiency.
Within the temperature-dependent critical current...
The inter-strand contact resistance in REBCO-based superconducting cables is a key parameter influencing current redistribution, AC losses, and cable stability. In this study, we measured the inter-strand resistance of short vertically stacked tape (VST) samples at liquid nitrogen temperature (77 K). The effective contact resistivities between the stabilizer and the REBCO tapes were estimated...
High-temperature superconductors (HTS) are promising candidates for use in the high-field magnets required for compact fusion reactors, such as the Spherical Tokamak for Energy Production (STEP). United Kingdom Industrial Fusion Solutions (UKIFS), in collaboration with Seoul National University and PowerNix, is developing vertically stacked tape (VST) HTS cables using ReBa₂Cu₃O₇₋ₓ coated tapes...
In fusion applications, cables made from high-temperature superconducting tapes are required to transport high currents in strong magnetic fields. Cable-in-conduit conductors (CICC) using multiple high-temperature superconducting (HTS) strands, such as the HTS conductor, meet these demanding requirements. This study presents experiments on a double casing conductor (DCC), a round HTS strand...
As compared with low-temperature superconducting (LTS) conductors where wires are typically fully transposed, simply stacked high-temperature superconducting (HTS) conductors may be argued as easier to be fabricated. However, brittleness of HTS tapes presents significant challenges for efficiently assembling them into HTS conductors. Once winding finished, it is preferable stacks are tightly...
Twisted stacked-tape cable in conduit conductor (TSTC-CICC) structure constitute a very promising technology due to their easy fabrication process, flexibility, and high current density. This paper introduces a 6-slot TSTC-CICC structure and a 20-meter-long cable is fabricated. To verify its performance, the cable was wound into a D-shaped coil and successfully tested at liquid nitrogen...
REBCO coated conductors have emerged as a promising option for high-field fusion magnet applications, thanks to their outstanding critical current performance. However, their high aspect ratio tape-like cross-section, anisotropic properties, and susceptibility to various transverse mechanical stresses require careful consideration in cable design, particularly to prevent issues like...
During the acceptance phase of the China Fusion Engineering Testing Reactor (CFETR) Central Solenoid Model Coil (CSMC), Paschen testing was conducted to verify the reliability of the insulation structure. To locate insulation faults during magnet testing, this study developed an Insulation Condition Monitoring System (ICMS) based on visible light imaging technology. The ICMS software,...
With the development of superconducting technology, high temperature superconducting (HTS) tapes can be mass-produced. With the advantages of high current density, zero resistance in superconducting state and high resistance in normal state, HTS tapes can be used to limit and interrupt fault current as a fuse. However, with the superconducting layer to load normal current, the critical current...
With the growing integration of renewable energy sources such as photovoltaics, research on DC systems has been actively performed. DC systems offer superior compatibility with renewable energy sources and lower power transmission losses compared to AC systems. However, it faces critical challenges, such as rapid increase of fault currents directly after a fault occurs and the absence of...
Induction motor starting often causes voltage fluctuations due to high inrush current, which can impact system stability and power quality. To address this, smart inverters with power control functions and superconducting fault current limiters (SFCLs) have emerged as promising solutions for reducing voltage instability. The power control of smart inverters ensures that the voltage at the...
In this paper, we present a 2-D numerical model based on a vector potential method and nonlinear E-J relationship to study the dynamic responses of multiple bulks of high-temperature superconductor(HTSC) levitated above different typical permanent magnetic guideway (PMG). Different from the existing related models and results of this subject, the coupling effects of different bulks are taken...
The Dresden High Magnetic Field Laboratory (HLD) is a pulsed-field user facility, which provides external and in-house researchers with the possibility to perform a broad range of experiments in pulsed magnetic fields [1]. Being a member of the European Magnetic Field Laboratory (EMFL), HLD offers access and supports more than 100 scientific projects annually. At the HLD, a diverse set of...
Split pulsed magnets are widely employed in high temperature superconducting (HTS) motor armature winding as magnetizing coils to implement in-situ pulsed field magnetization (PFM) for HTS field pole magnets. We have designed and developed a split pulsed magnet, that balances a peak central magnetic field of nearly 7 T and a rise time of 24 ms, making it particularly suitable for PFM of HTS...
The flat-top pulsed magnet field (FTPMF) can achieve the fields above 40 T with long duration, which enables the development of the terahertz gyrotron of 1THz with the operation width longer than 1 ms. The performance of the gyrotron is significantly influenced by the stability of FTPMF. Using a small compensation coil built into the bore of the magnet is a practical method to achieve the...
Quasi-force-free magnets, with their small volume and low inductance characteristics, are considered a promising option for the magnetic system in THz gyrotrons. However, the current quasi-force-free magnets suffer from complex structures that are difficult to fabricate. Moreover, due to the inherent instability of their structure, a dielectric with a sufficiently high Young's modulus needs to...
A high field pulsed magnet up to 35 T, cooled by a cryogenic refrigerator, has been developed for ultrafast spectroscopy at Wuhan national high magnetic field center (WHMFC). To cool the magnet fast, two thin beryllium copper sheets are chosen as end plates and reinforced with epoxy. The beryllium copper sheets are linked with a cryogenic refrigerator to ensure the magnet can be cooled down to...
The development of superconducting diodes has significant interest for their potential to revolutionize advanced magnetic systems such as magnetic systems powered by a flux-pump. A novel method for producing a passively controlled superconducting diode has been developed. The design is based on high-temperature-superconducting (HTS) conductor technology with the use of a ferro-magnetic yoke. A...
A superconducting diode is a device whose critical current is different depending on the direction of the current. It can be obtained using REBCO tapes,in which rectified motion of flux quantum is observed [1]. In this study, we develop a concept of wireless HTS magnet charging utilizing such HTS REBCO diodes. This concept was first we introduced at the last Applied Superconductivity...
Flux pumps are gaining traction as alternatives to traditional power supplies for HTS magnets due to their reduced heat-leak and compactness. Automatic flux pumps are the simplest embodiment and rely on a section of superconductor parallel to the load magnet, known as the bridge, being driven outside its critical surface by an induced voltage on the secondary of a transformer. Most previously...
No-insulated (NI) high-temperature superconducting (HTS) magnets exhibit several advantages over conventional insulated (INS) magnets. The inherent turn-to-turn resistance of NI magnets facilitates the dissipation of localized hotspots, significantly reducing the risk of quenching and improving thermal management. These characteristics make NI magnets especially attractive for high-field...
High-temperature superconductor (HTS) magnets have demonstrated significant potential for generating high magnetic fields and transporting DC current with minimal power loss, making them essential components in advanced applications such as NMR, MRI, and superconducting motors. Despite the advantages, the high joint resistance of HTS magnets has limited the adoption of persistent current mode...
This presentation explores the potential for using bulk BSCCO-2223 as a material for High-Temperature Superconducting (HTS) switches. HTS switches typically utilize ReBCO wire (2G HTS). Switching is achieved using either applied AC or DC magnetic fields, an increase in temperature, or both. Such methods reliably and repeatably modulate effective resistance between a closed- and...
OpenStar is advancing fusion energy generation through the development of a levitated dipole reactor, building on the Levitated Dipole Experiment (LDX) concept. This approach integrates high-temperature superconducting (HTS) magnets with an onboard superconducting power supply.
Having successfully demonstrated the feasibility of integrating HTS magnets into the levitated dipole concept,...
The Muon Collider (MC) embodies a groundbreaking concept in circular colliders for high-energy physics, offering a unique pathway to achieve unprecedented energy and luminosity of the colliding partons while significantly reducing environmental impact compared to conventional collider technologies. A critical aspect of its feasibility lies in the development of cutting-edge superconducting...
The increasing demand for REBCO wires from various magnet applications such as that for the HTS-based compact fusion, accelerators, transportation, medical and analytical systems is driving the increase in our production capacity and the further improvements in wire performance and qualities. In the last several years, SuperPower was focusing on advancing the wire manufacturing technologies....
The Volumetric Neutron Source (VNS) is a steady-state tokamak designed to bridge the technological gap between ITER and DEMO by enabling full-scale testing of tritium breeding blankets and other fusion reactor components under DEMO-relevant conditions. The VNS magnet system features an innovative magnetic cage architecture, where the superconducting poloidal field (PF) coils are positioned...
The Muon Collider represents an exciting proposal for a post-LHC accelerator, capable of exploring higher-energy regions with greater power consumption efficiency compared to hadronic alternatives, while avoiding synchrotron radiation limitations inherent in electron colliders.
This contribution will focus on the magnets for the Muon Collider storage ring. These magnets pose an...
RE-based High Temperatures Superconductors (HTS) are expected to be applied in various fields due to their high in-field critical current (Ic) and mechanical properties.
Fujikura Ltd. has developed high-performance RE-based HTS using Ion Beam Assisted Deposition (IBAD) and Pulsed Laser Deposition (PLD) techniques, and has supplied to various customers for many years.
Fujikura mainly has two...
The Spherical Tokamak for Energy Production (STEP) is the United Kingdom's next-generation publicly funded fusion power plant prototype, aiming to export 100 MW of electrical power to the grid. For all magnets, the basic requirements imposed by the plasma and the spatial constraints are provided, as well as the anticipated modes of operation where applicable. Then, the most up-to-date concept...
The Muon Collider (MC) is one of the options under study as the next step for high-energy physics beyond the Large Hadron Collider. The magnets for a MC, largely based on high-temperature superconductors (HTS), bear some of the most pressing technology challenges and will require intense development and demonstration in the next years. The “target decay and capture solenoid”, a high field...
SuNAM has long been at the forefront of coated conductor (CC) technology, leveraging its proprietary Reactive Co-evaporation-Deposition and Reaction (RCE-DR) process to meet diverse industry needs, particularly in grid applications. However, the emergence of compact fusion reactors has presented unprecedented challenges, demanding in-field critical current performance that surpasses the...
CTRFR-1 (Compact Tokamak-based Repetitive Fusion Reactor-1, R = 1 m, a = 0.56 m, A = R/a = 1.8, B0=3.2 T, Q=1) is the next-generation high-temperature superconducting (HTS) spherical tokamak (ST) designed by Shannxi Startorus Fusion Technology Co., Ltd., a commercial fusion enterprise from China. The spherical tokamak is an economical and fast-building option for a fusion reactor, which allows...
Over the past decades, the superconducting magnet community has proposed various concepts to protect magnets from the undesired consequences of a quench. While only a handful of protection methods have been implemented in large-scale production magnets, other less-known concepts have been explored only at a conceptual stage. This study presents various protection techniques that are either...
High-temperature superconducting (HTS) REBCO tapes are being developed for practical use in high-field applications such as medical imaging and nuclear fusion. These tapes achieve current densities exceeding 800 A/mm² at 20 K and 20 T, made possible by incorporating artificial pinning (AP) particles that enhance their magnetic field resilience and overall performance. Mechanical stability is...
In the past few years, with the continuous improvement of the performance requirements for superconducting magnets in future compact fusion devices, China has been committed to the design and manufacture of superconducting magnets. At present, the comprehensive design of low temperature superconducting (LTS) magnets for next generation fusion reactors in China has been finalized, encompassing...
Large particle accelerator facilities for medium-high proton and heavy ion beamlines extensively rely on normal conducting magnets which, while effective, suffer from significant energy losses due to resistive heating in their copper coils. One successful strategy for improving these facilities involves upgrading their existing infrastructure by replacing resistive magnets with magnesium...
Establishment of stable and reproducible mass-production method for high performance REBCO coated conductors (CCs) is now crucial issue to realize practical applications of REBCO CCs in industrial scale for such application as compact fusion reactor. Critical current, Ic, of the wire is one of the most important material parameters in the CCs. The steepness of the current-voltage (I-V)...
The MOLLER experiment at the Thomas Jefferson National Accelerator Facility (JLab) aims to precisely measure the weak interaction between electrons. This experiment leverages the 12 GeV electron beam and will run for three years. A crucial component of MOLLER is a system of five uniquely shaped water-cooled toroidal magnets. These magnets, possessing seven-fold symmetry, are designed to focus...
With the beneficial characteristics of high irreversible field, high superconducting transition temperature and high critical current density, REBCO material has reached the stage of mass commercial production. Meanwhile a large number of superconducting power transmission projects and superconducting magnets have been developed using REBCO tapes. Recently, due to the significant demand for...
The EPOS stellarator, a compact device for confining electron-positron plasmas, will leverage high-temperature superconductors (HTS) to generate a highly optimized toroidal magnetic field. To achieve this, we will employ non-planar, non-insulated coils made from rare-earth barium copper oxide (ReBCO) tapes, which enable a 2T magnetic field on axis and a plasma volume of approximately 10L. We...
The APEX (A Positron Electron eXperiment) collaboration is developing a “tabletopsized”
stellarator, EPOS (Electrons and Positrons in an Optimized Stellarator). In this
work, we present ReBCO non-planar, non-insulated (NI) coils designed to confine pairplasmas
within a quasi-axisymmetric magnetic field of 2.0 T on axis. The stellarator’s
small size enhances its utility by reaching higher...
The “Canis” 3x3 array of high-temperature superconductor (HTS) planar coils was designed, manufactured, and tested by Thea Energy, Inc to demonstrate the viability of its core technology to generate stellarator magnetic fields for “Eos”, the company’s first integrated fusion system. The Canis 3x3 magnet array demonstrated the ability to create complex magnetic field shapes with sufficiently...
Magnetic confinement fusion devices, such as tokamaks and stellarators, use coils to confine plasma in a toroidal shape. Tokamaks rely on D-shaped pancake coils but also require a toroidal current in the plasma to generate the desired magnetic fields. Stellarators, on the other hand, avoid the need for a plasma current by relying solely on external coils, which leads to complex 3D coil...
The direct-fusion-drive device is a compact nuclear fusion engine that uses magnetic-confinement to achieve fusion reactions, providing both thrust and electrical power for spacecraft. Its operating principle is based on particle-confinement using extremely high magnetic fields exceeding 20 tesla to confine plasma. Subsequently, an electric field accelerates the plasma to initiate fusion in...
S.M.A.R.T. promises to be the boldest design to generate aneutronic fusion energy, first as process heat, and then as electricity for the power grid. I propose to incorporate 27 novel features to enable the Toroidal-Field (TF) system--with its brittle ceramic HTS conductor--to survive the peak stresses--and strains--from the (J x B) Lorentz forces generated by a peak ambient field of more...
The Standard Model of particle physics is not a perfect theory. Many experiments seek to observe phenomena beyond the Standard Model to fix it.
COMET experiment (COherent Muon to Electron Transition) is planned to be conducted at J-PARC. COMET aims to find the neutrinoless transition of muon to electron, known as “µ-e conversion.” To find this process, the first stage of COMET, COMET...
The MARCO magnet is a 2T superconducting solenoid magnet central to the Electron Ion collider (EIC) detector at Brookhaven National Laboratory (BNL). The magnet utilizes a Rutherford cable in channel conductor with a nominal current of approximately 4 kA at 4.5 K. The cable and the copper stabilizer design was refined to aide fabrication of a 50 m long sample conductor. The characteristic of...
The High-Luminosity LHC (HL-LHC) project aims at upgrading the existing LHC machine to increase its integrated luminosity by a factor of ten. A key aspect of this upgrade are the inner triplet (or low-β) quadrupole magnets, the MQXF, which utilize Nb3Sn superconducting magnet technology and reach a conductor peak field of 11.3 T. The MQXFB version, manufactured at CERN, is characterized by a...
Among the most innovative and promising next generation particle accelerators, a muon collider is at a time a viable compromise between the increase of available energy at the interaction point and the sustainability of the related infrastructure. The International Muon Collider Collaboration is pursuing the design of a complete accelerator complex, up to the detectors to be installed on the...
One of the goals of the High Field Magnet (HFM) Programme at CERN is to explore High-Temperature Superconducting (HTS) magnet technology for accelerator applications that go beyond the limits of low-temperature superconductors and offer a pathway for the development of more sustainable particle accelerators operating at temperatures above 1.9 or even 4.5 K. As a stepping stone to achieving...
Joint technology is one of the key technologies for the application of second-generation high-temperature superconducting (2G HTS) tapes. The simplicity of the joint fabrication method and the excellence of the electrical and mechanical properties of the joints significantly impact the performance of REBCO in large-scale applications. Copper bonding joint technology, a new type of solder-free,...
The solder layer in electronic systems has been the subject of a vast number of studies in the field of reliability assessment due to the weakness of this layer and the large difference between its mechanical characteristics and those of the rest of the system. Among these characteristics, the difference in the coefficient of thermal expansion drives the generation of thermal stress, which can...
Rare-Earth Barium Copper Oxide (REBCO)-based High-Temperature Superconductor (HTS) tapes are used for large-scale applications, which typically require spools longer than those currently produced. Therefore, several joints are often needed for a single project, emphasizing the importance of low-resistivity, mechanically strong, and repeatable joints. Currently, soldering is one of the most...
High-Temperature Superconducting (HTS) magnets, composed of multiple pancake coils made from Second Generation (2G) HTS tapes, offer significant advantages due to their superior performance in elevated magnetic fields and temperatures compared to traditional low-temperature superconductors. A critical aspect of manufacturing these magnets is creating reliable joints, which transfer current...
To achieve a controllable operating temperature for superconducting magnet devices, the development of cryocooler-cooled superconducting magnets has garnered significant attention. Typically, the excitation current of commercially available cryocooler-cooled superconducting magnets ranges from approximately 100 to 200 A. However, increasing the excitation current of superconducting magnets is...
The concept of a rotating cryocooler for superconducting rotating machines eliminates the need for cryogenic liquids in the cooling loop, thereby simplifying and compacting the cooling system. This approach enables the development of extremely lightweight machines with high torque density. However, at high rotational speeds (e.g., >3000 rpm), operational conditions often limit the...
In the United States, a NASA University Leadership Initiative program with The Center for Cryogenic High-Efficiency Electrical Technologies for Aircraft (CHEETA) and a separate ARPA E Connecting Aviation By Lighter Electrical Systems (CABLES) program have been developing 2 kA-rated, medium voltage, and lightweight quick connectors for aerospace. These quick connectors will also permit a...
The fabrication of high-temperature superconductor (HTS) magnets often involves manual soldering joints, which relies on operator skill and causes performance variations. To address these challenges, this study presents the design, fabrication, and experimental evaluation of a roller-shaped HTS coil joint apparatus for soldering rare-earth barium copper oxide (REBCO) tapes. The apparatus was...
In this study, different types of joints (lap joint and bridge joint) using commercially available second-generation (2G) high-temperature superconductor (HTS) tapes from two manufacturers were prepared, and their I-V characteristics were studied at 77 K, liquid nitrogen temperature. Both types of joints were prepared by taking each sample of HTS tapes with effective overlapping lengths...
We have fabricated Gd123 thin films co-doped with several kinds of RE₂CuO₄ (RE214: RE = Gd, Nd, Sm, Eu) by the FF-MOD method and investigated their superconducting properties. We have already reported that the introduction of the superconductor RE214 (Tc = 18.5 K) as an artificial pinning center (APC) into RE123 thin films which improved the Jc-B properties for the first time...
This study presents a method for addressing defects in 2G high-temperature superconducting tapes using the REBCO Repair Patch (RRP) and analyzes its effects on performance enhancement. The main focus of the research includes an analysis of defect cases in the tapes and an experimental evaluation of performance improvements after the installation of the patch on defective tapes. Experiments...
When considering the application of coated conductors to ac equipment such as motors and generators, it is necessary to reduce ac losses, especially hysteresis losses caused by external ac magnetic fields, by multifilamentation. In multifilament coated conductors, the finer the filament, the better, since the overall hysteresis loss is reduced inversely proportional to the filament width....
REBCO coated conductor has great potential to be used in ultra-high field magnets [1]. In such magnets, it is crucial to manage the high mechanical stress on REBCO due to electromagnetic force. The commercial REBCO tapes is strong in the longitudinal direction but is prone to delamination by tensile stress in the thickness direction. It had been observed that transverse tension by...
In-field critical current density Jc properties in high-Tc superconductors are significantly affected by the morphology of nano-sized crystalline defects acting as pinning centers (PCs): the optimization in the shape and spatial distribution of PCs is one of important issues on development of REBa2Cu3Oy (REBCO) coated conductors (CCs) for superconducting magnet applications and even on...
High-temperature superconductors (HTS) REBCO (Rare Earth Barium Copper Oxide) tapes are key candidates for applications in fusion reactors and high-energy particle accelerators due to their excellent critical current densities and high magnetic field tolerance. However, their performance in radiation-intensive environments, particularly under neutron irradiation, remains a crucial research...
The parallel-wound No-insulation (PWNI) high temperature superconducting (HTS) coil is a novel type of pancake-shaped no-insulation coil made by parallel-staked HTS tapes, which is a promising solution for high field magnets. Previous studies have analyzed the electromagnetic characteristics of a PWNI HTS coil during the ramping process through simulations. The current distribution of these...
No-insulation (NI) technology is widely adopted in REBCO coils due to its lower risk of electrical burnout, attributed to the turn-to-turn current-sharing feature. However, the contact resistance of NI coils is difficult to control under the influence of REBCO tape preparation process, coil winding and the cooling cycles. When contact resistance increases to a level that prevents bypass...
In the context of accelerator and fusion magnet applications, high-temperature superconducting (HTS) coils must maintain stable performance over extended periods post-installation, during which they undergo multiple thermal and magnetic cycles. This study investigates the stability of REBCO MI/NI coils under repeated thermal cycling and periodic electromagnetic loading. The degradation of Ic...
Non-insulation (NI) high-temperature superconducting coils are widely utilized owing to their high current-carrying density, high thermal stability, and self-protection features. However, in engineering applications, the primary challenge associated with NI coils is charging delay, along with two additional issues. Firstly, in a closed-loop NI coil, once the Persistent Current Switch (PCS)...
The transformer in the power supply is naturally sensitive to the external magnetic field, and its operating characteristics are easily changed under the influence of the strong external stray magnetic field, resulting in the change of the operating characteristics of the power supply and even failure. Therefore, the establishment of an accurate transformer model under the external magnetic...
For designing high-field electromagnets, the Lorentz force on coils must be computed to ensure a support structure is feasible, and the inductance should be computed to evaluate the stored energy and dynamics. Also, the magnetic field and its variation inside the conductor is of interest for computing stress and strain, and due to superconducting quench limits. For these force, inductance,...
Using MACSYMA—the superb computer calculus program developed at MIT in the 1970s, ‘80s, and ‘90s—I have derived, verified, and meticulously simplified the analytic formulas for all magnetic quantities generated by any system of coaxial, axisymmetric, rectangular-cross-section (RCS), uniform-current-density (UCD) coils. All formulas now have the same constant of integration—zero—verified by...
The finite element analysis method is a commonly used and accurate approach for calculating the stress in electromagnetic coils. However, for dry-wound coils with nonlinear contact behavior, especially those with many turns, these methods are often time-consuming and may have convergence issues. Therefore, this study proposes a semi-analytical stress analysis method specifically designed to...
High-temperature superconductors (HTS), particularly rare-earth barium copper oxide (REBCO), are critical for ultra-high-field magnets in next-generation accelerators and compact fusion reactors due to their superior performance under high magnetic fields. However, existing characterization techniques cannot continuously evaluate long HTS conductors under simultaneous low-temperature and...
REBCO tapes stand out as the most promising conductors for a large variety of applications yet being still far from being fully understood on both the theoretical and experimental sides.
For this purpose, within the PNRR-IRIS project currently at its final phase, a 10 T cryogen free dipole magnet demonstrator fully built with HTS has been designed and is being manufactured, namely ESMA...
Advanced automation tools are promising wide-range solutions for the various problems still affecting High-Temperature Superconducting (HTS) magnets, including Non-Insulated (NI) ones. State-of-the-art techniques have the potential to enable online monitoring and control of these devices, significantly enhancing their operational robustness to the extent of entirely preventing quench events,...
OpenStar Technologies Ltd. is advancing fusion research through the development of a levitated dipole reactor inspired by the Levitated Dipole Experiment (LDX). The reactor design includes two main magnet components: a suspended, doughnut-shaped high-temperature superconducting (HTS) magnet at the chamber's center, and a top magnet above the chamber to maintain stable magnetic levitation....
Within the framework of the study of future high-energy particle colliders, high-field (15-16 T) Nb3Sn magnets are being developed. These magnets are usually impregnated using epoxy resin with glass fiber to provide electrical insulation and mechanical support to the conductor.
However, several phenomena are often observed: first, the high-stress conditions applied during pre-load, cool-down,...
High-temperature superconductors (e.g., REBCO) are key to developing high-field magnets for next-generation high-energy circular colliders and compact fusion reactors. The U.S. Magnet Development Program, in collaboration with industry, is advancing REBCO magnet technology through multi-tape CORC® wires. Conventional sensors (strain gauges and voltage taps) are becoming insufficient to provide...
For advancing the development of fully superconducting tokamak magnets and accelerating the progress to the next step in fusion reactor DEMO design, a refined and integrated large-scale superconducting tokamak simulation platform is being developed in China. The aim is to optimize the design and performance of tokamak magnets, improve their efficiency and reliability, solve complex...
The spherical tokamak (ST), characterized by its low aspect ratio and compact geometry, necessitates a toroidal filed (TF) coil design that typically adopts a sharper D-shape profile. This design is distinguished by its slender and tall configuration with a reduced radius of curvature, which can result in localized magnetic field and stress concentration on coils. Furthermore, the...
Future fusion devices must leverage the advantages of high temperature superconductors. To meet this challenge, a novel Rutherford-type cable winding of superconducting (REBCO) tape stacks has been proposed. This cable, known as the Flat Round-Edge Former Tape Cable (FReTC) is comprised of several multi-tape subcables wrapped around a flat, round-edge former. As part of enabling the use of...
A design of a Rutherford cable (Rfc) consisting of a copper core and 10 Quasi-isotropic Strands with symmetrical geometry has been proposed. In this paper, a preliminary sample of the Rfc is fabricated by partially-filled Q-ISs. The cable sample’s self-field critical current and critical current dependence on the magnitude and orientations of the magnetic field are measured in liquid nitrogen....
Bi-2223 high temperature superconducting (HTS) tape has shown high mechanical stability and current capacity, which could be a potential material of cable-in-conduit-conductor (CICC) design and manufacture for fusion magnets. During winding process of magnet coil, bending strain is induced which cause the current capacity degradation. Thus, the bending performance of CICC cable is needed to be...
High magnetic fields of up to 20 T in tokamak-type fusion devices, such as in Central Solenoids of European DEMO and the Chinese BEST fusion reactors, require High-Temperature Superconductors (HTS) and a promising candidate is ReBCO tape. The large Lorentz forces occurring under these operating conditions may locally generate very high values of mechanical stress, which can irreversibly...
REBCO coated conductor, the second-generation high-temperature superconducting (HTS) material, is one of the most promising materials for application in future fusion reactor high-field magnets due to its high critical current density and excellent mechanical properties. The Institute of Plasma Physics, Chinese Academy of Sciences (ASIPP) is conducting the research and development activities...
In this paper, we develop a new thermal-hydraulic simulation module as part of the Tokamak magnet software under development. The module focuses on the coupling effect between thermo-hydraulics and electromagnetism to study the LTS/HTS cable-in-conduit-conductor (CICC) stability margin and quench characteristics. The algorithm of the program is based on the finite element method. We present...
The transition from low-temperature superconductors (LTS) to high-temperature superconductors (HTS) has opened new possibilities for toroidal field coil design in fusion applications. These next-generation HTS coils represent a significant departure from traditional D-shaped LTS coils, introducing unique operational dynamics and challenges. A key innovation is the adoption of HTS stacks, where...
High-temperature superconductor (HTS) magnets are gaining attention for their vital position of compact, high-field tokamaks, helping speed up the path to fusion energy. In future commercial nuclear fusion plants, steady-state operations lasting several months will be required. One of the main challenges for steady-state operation is the instability of plasma confinement, which can be reduced...
Superconducting coils utilizing VIPER-like HTS cable for tokamaks and
stellarators are being designed, built, and tested. In order to assess a coil's ability to operate at the desired current, and/or to evaluate
possible degradation of a coil's performance due to manufacturing
processes, it is necessary to calculate the expected critical current, Ic, of the coil. This is actually a...
The Magnet Cold Test Bench (MCTB) will be assembled and commissioned in 2025 with existing ITER systems (Cold terminal Box, Cryogenic system,) and new components (cryostat, power supply, interconnection valve box). The objective is to test as many TF coils as possible in the MCTB without impacting the assembly schedule in the pit. ITER TF magnet system consist of 18 coils. The Current sharing...
Supplying high current to a superconducting magnet incurs significant conduction losses through current leads. Due to the limitations imposed by the Wiedemann-Franz Law, the minimum loss is independent of the lead material and is 45 W per 1,000 A of DC current.
Here we propose and demonstrate a synchronous rectifying DC current drive with no thermal linkage between room temperature and...
OpenStar Technologies Ltd is pursuing a levitating dipole reactor (LDR) for fusion energy production. In this concept, fusion plasma is confined around a single dipole magnet. The scaling and deployment of the LDR concept and beyond relies on the development of integrated power supply systems. These devices, so-called flux pumps, have the ability to maintain the current in the magnet while it...
The aviation industry has committed to a long-term global goal of net-zero carbon emissions by 2050. Zero Emission Sustainable Transportation 1 (ZEST1), which was funded by UK's Aerospace Technology Institute and consorted by 10 partners led by Airbus, aims to accelerate technology breakthroughs to enable zero emission commercial aircraft by 2030. Within the consortium, the University of...
Converters composed of thyristor full bridges are commonly used to feed superconducting coils and test magnets. Since magnets mostly operate in the steady state, converters under symmetric firing generate significant reactive power. In this paper, a design of the 0°/-180°phase-shift converter is proposed with asymmetric firing to reduce fundamental reactive power, and the even harmonics...
The 42-MW highly stabilized power supply, developed by the High Magnetic Field Laboratory, Chinese Academy of Sciences (CHMFL), successfully energized a newly designed water-cooled resistive magnet, achieving a world-record magnetic field of 42.02 T in September 2024. This power supply system is composed of a newly developed 14-MW power supply in parallel with a pre-existing 28-MW unit. The...
The high voltage power supply system of the pulsed high magnetic field facility at Wuhan National High Magnetic Field Center (WHMFC) will be upgraded to 167 MJ capacitor banks with 73 modules for 27 magnet experimental stations in 5 years. The capacitor bank power supply system and all magnet experimental stations are located on the second and first floors of the same building (Pulsed...
This paper presents the design of a high-voltage power supply based on insulated core transformer, specifically tailored for electron irradiation accelerators to meet the demands of irradiation processing applications. The segmented magnetic core structure, however, inevitably leads to leakage issues, complicating the design of this high-voltage power supply. To develop a high-performance...
High-temperature superconducting REBCO coated conductors have strong potential for high-field magnet applications. Significant technology gaps, however, need to be filled before we can fully leverage the conductor capability for future accelerator magnets. The U.S. Magnet Development Program is collaborating with conductor vendors to address this need. We report on the fabrication and test of...
The 'Little Big Coil (LBC)' magnet test bed investigates key coated conductor characteristics in a high field and high stress environment by testing a REBCO coil in the bore of the NHMFL 31.1 T Bitter magnet. Indeed, LBC3 first demonstrated excessive screening current stress (SCS) resulting in wavy plastic conductor damage, while obtaining the record-high DC magnetic field of 45.5 T by...
The European Synchrotron Radiation Facility (ESRF) is currently working on the development of a new synchrotron light source for its beamline BM18. The proposed source is a short wiggler composed by three pairs of magnetic poles, delivering a peak magnetic field of 1.58 tesla. A crucial requirement is the possibility of performing scans of the magnetic field intensity, while keeping the...
Rare-Earth Barium Copper Oxide (REBCO) coated conductors are an attractive option for application in high-field accelerator magnets due to their high critical field and the convenience of fabrication without heat treatment compared to some other superconductors.
Fermilab plays a vital role in superconducting accelerator magnet R&D under the framework of the U.S. Magnet Development Program....
The no-insulation technique in high-temperature superconducting (HTS) coils has significantly advanced HTS magnet technology by introducing an innovative approach to protection. This technique allows current redistribution between adjacent turns, enabling self-protection of the coils. However, it also introduces charging delays. To reduce the charging delay while maintaining self-protection...
In 2022, a collaborative team led by Pohang Accelerator Laboratory, Seoul National University and Kangwon National University began the development of a 5 T metal-insulated high-temperature superconducting (HTS) wavelength shifter (WLS) magnet, aiming to enhance the brilliance of photons by 1,000 times at 100 keV in Pohang Light Source II. In 2023, we reported test results of the magnet in a...
High Temperature Superconductors (HTS) offer significant potential for very high field dipole. We started the development of REBCO-insulated dipole magnetsin 2010 with EUCARD and EUCARD2 programs. CEA Paris-Saclay then chose to apply the Metal-as-Insulation (MI) REBCO winding, originally developed in the 32.5 T solenoid insert project NOUGAT, the design, fabrication and tests of HTS high field...
High temperature superconductor (HTS) coils are widely acknowledged for having greater stability margins than low temperature superconductor (LTS) counterparts. In particular, no-insulation (NI) coils are often assumed to exhibit even greater stability owing to enhanced thermal conduction between turns and inherent current bypass capabilities. However, we hypothesize that this assumption may...
To achieve a short-period, high-field undulator using HTS tape, we propose novel winding methods specifically designed for this purpose. Given the minimum bending radius constraint of HTS tape, conventional horizontal winding has been considered unsuitable for short-period undulators, leading to a primary focus on vertical winding. However, to overcome this limitation, we introduce an...
The US Magnet Development Program (USMDP) is pursuing hybrid dipole magnet testing with low temperature superconductor (LTS) outserts and high temperature superconductor (HTS) inserts, as an efficient way to characterize HTS magnets at higher fields and stress levels. In this work, we present the test and performance characterization of the first hybrid dipole test at the recently upgraded...
Advancements in high-temperature superconductors (HTS), particularly REBCO coated conductors, have catalyzed breakthroughs in ultra-high field magnet technology. However, significant challenges remain, with quench protection being a critical unresolved issue. The no-insulation (NI) winding technique offers a promising approach to mitigate these challenges. By allowing turn-to-turn bypass...
A 50-period bulk high-temperature superconducting (HTS) undulator, utilizing a staggered-array configuration of RE-Ba-Cu-O bulk superconductors and magnetized by a 7 T solenoid magnet, is currently under development at Zhangjiang Laboratory for Shanghai Soft X-ray Free Electron Laser (SXFEL) facility [1-2]. The device operates through multiple temperature control stages for the HTS insert,...
The novel uni-layer concept for superconducting magnets introduces a new geometrical approach to form a magnetic field orthogonal to an aperture. The new design allows for independent single layers, eliminating the need for internal layer jumps and favoring the use of grading, while maintaining high efficiency in the use of conductor. The unique attributes of the uni-layer concept are...
No-insulation (NI) high-temperature superconducting (HTS) coils have been shown to have improved thermal stability properties and an improved winding pack density over traditionally wound HTS coils. These improved properties have led to new design proposals for a wide range of applications, include some of the magnets of a fusion magnet system. However, further research still needs to be...
High-temperature superconducting (HTS) materials have attracted significant interest for use in insertion devices due to their higher critical temperature, Tc and larger critical current density, Jc compared to low-temperature superconducting wires [1-3]. These properties enable the development of undulators with shorter period and larger on-axis magnetic field. Helical undulators, which...
Building on the initial magnetic design of DAISY, the 14 T common coil magnet demonstrator being developed at CIEMAT under the High Field Magnet (HFM) programme, this paper investigates the feasibility of hybrid designs combining Nb₃Sn and NbTi for high- and low-field regions, respectively. The primary goal is to minimise superconductor usage while ensuring that the magnet meets the functional...
Parallel-wound no-insulation (PWNI) high-temperature superconducting (HTS) coil is a kind of pancake-shaped coil wound with parallel-stacked tapes, which is a promising technique with reduced ramping delay and enhanced thermal stability compared to conventional no-insulation coils wound with single tape (single-wound no-insulation (SWNI) coil). The turn-to-turn current redistribution...
A 12 mm-period, 0.6 m-long HTS undulator, employing staggered-array Gd-Ba-Cu-O (GdBCO) bulks and magnetized by a 7 T superconducting solenoid, is currently being fabricated at Zhangjiang Laboratory for deployment at the Shanghai Soft X-ray Free Electron Laser (SXFEL) facility [1-2]. Realizing an undulator field with an RMS phase error of only a few degrees requires approximately 100...
Several high-field dipole magnets have been developed at the Institute of High Energy Physics, Chinese Academy of Sciences (IHEP, CAS) for preliminary research on next-generation high-energy colliders such as the Super Proton-Proton Collider (SPPC), Future Circular Collider (FCC), and others. Following the achievement of a 12.47-T main field at 4.2 K by the LPF1 magnet in 2021, IHEP is...
Fast-ramping REBCO HTS magnets are required for the central solenoid and poloidal field coils of spherical tokamaks. Beyond fusion, this class of magnets has broad relevance to a range of emerging applications including motors and generators, space propulsion, manufacturing and other sectors. These magnets cannot adopt no-insulation (NI), which offer the most compact route to high fields using...
A new testing facility employing a 15-T transverse field to evaluate the full-service-field characteristics of superconducting materials is now under development in China. A key objective is the development of a large bore, 15-T dipole magnet to provide the transverse magnetic field load. In this study, we designed and constructed a compact high-temperature superconducting (HTS) dipole magnet...
Nearly four decades have passed since the first discovery of high temperature superconductor (HTS). To date multiple HTS wires have been developed and some of them are now readily available in a commercial market. REBCO has been regarded as one of the most advanced HTS wire options with the benefit of large in-field current carrying capacity and strong substrate mechanical toughness. The...
In practical high-temperature superconducting (HTS) applications, various harmonics are present, causing the transport current to become non-sinusoidal, which may pose new challenges for controlling AC losses. However, the transport AC loss characteristics of REBCO coated conductor (CC) with magnetic substrates under non-sinusoidal currents are still unclear. In this study, we performed a...
For practical applications such as power cables and transformers using high temperature superconducting (HTS) tapes, it is necessary to reduce the losses of HTS tapes. We have investigated the reduction of background loss, which is the apparent loss that occurs even where there is no specimen in the pickup coil, in order to improve the sensitivity of the AC loss measurement for HTS tapes using...
A non-contact method for estimating critical current is proposed, which can be applied to both single superconducting wires and various types of cables with multiple superconducting wires. The authors have previously proposed a method for measuring magnetization loss of a superconducting wire as a means of non-contact estimation of the critical current of a single superconducting wire. Since...
The magnet system for the Material Plasma Exposure eXperiment (MPEX) provides the necessary field profile to enable rf source and heating along the length in order to meet the desired key performance parameters (KPPs) at the target area. In addition to the magnet system, MPEX has other systems (vacuum, diagnostics, rf source and heating) that operate in close proximity and require shielding...
AC losses significantly impact the design and operation of superconducting power devices, making their fast and accurate calculation essential. However, calculating AC losses in high-temperature superconducting coils often requires substantial computational resources. This paper proposes an artificial neural network (ANN) model with a Transformer architecture to calculate AC losses in...
The MgB₂ wire manufacturing process at ASG Superconductors has reached an advanced level of maturity, ensuring high reproducibility and homogeneity in long-length superconducting wires and tapes. These wires are available in various sizes and configurations, with single-unit lengths extending up to 6–7 km. The wires exhibit excellent mechanical properties, tailored through the careful...
This paper presents the design of the FCC-ee booster dipole magnets. The booster dipoles are low-field iron-dominated cycled H-type magnets. They consist of an 11 meter long laminated steel yoke with anodized aluminum busbars instead of coils. The magnet is designed to mitigate parasitic effects, namely the Earth’s magnetic field and yoke hysteresis, that become significant at the 6.5 mT field...
For the development at CERN (European Center for Nuclear Research) of the post-LHC accelerator infrastructures, HL-LHC (High Luminosity Large Hadron Collider) and FCC (Future Circular Collider), a new generation of magnets with extreme mechanical constraints, capable of generating high-quality magnetic fields of the order of 14T (operational) and energy efficient will be required. These...
The Circular Electron Positron Collider (CEPC), to be hosted in China in a circular underground tunnel of approximately 100 km in circumference. A 4-layer superconducting solenoid with cold bore of 7.07m serves as a key component of the large electron collider, providing a uniform and stable magnetic field for the detector. Due to the high magnetic force at 3 Tesla field inside the winding,...
The injector operating within the 3–15 MeV energy range is considered to hold significant potential for various practical applications, with broad prospects demonstrated in scientific experiments and industrial applications. For such typical injectors, the precise measurement of beam quality through a beam diagnosis system is considered crucial. The development of a universal beam diagnosis...
Investigations into the existence of Axions, a hypothetical Dark Matter candidate, have led to numerous experiments requiring stable magnetic fields over a large volume for an extended duration of time, a feat currently limited to low-temperature Niobium-based superconductors. While Nb-Ti is the standard at 4.2 K and <10 T, $Nb_{3}Sn$ has a larger $T_c$, larger $H_{c_{2}}$, and most...
As a recently developed type of dipole field magnets, the tilted solenoids technology has great potential in various fields such as proton therapy, particle accelerators, and high-field applications. High-temperature superconducting materials can further enhance the magnetic field strength, reduce the bending radius, and lower the device cost. This research is based on differential geometry...
The current 28 GHz Electron Cyclotron Resonance Ion Sources (ECRISs), constructed with Nb-Ti wires and conventional sextupole-in-solenoid or unconventional solenoid-in-sextupole structure, have utilized about 90% of the critical limits of the Nb-Ti wires to achieve maximum operating frequencies of up to 28 GHz. To produce an ECRIS capable of operating at fields required for frequencies of...
In this work, we present the design of a combined-function Canted-Cosine-Theta (CCT) accelerator magnet with an elliptic aperture and report progress on the fabrication of a NbTi demonstrator magnet. This unique bore shape is desired for fixed-field accelerators to accommodate horizontal orbit offset between beams of different energy. We first share the magnetic and mechanical design of a...
For REBCO magnets, the no-insulation (NI) winding technique, which eliminates turn-to-turn insulation, is considered a key approach. The NI technique offers advantages, particularly during quench events, as the absence of turn-to-turn insulation allows current to bypass localized heat sources or defects naturally. In fact, several studies have reported that NI magnets achieved higher operating...
This paper presents both numerical and experimental investigations aimed at achieving accurate measurements of critical current in no-insulation (NI) high-temperature superconducting (HTS) coils. Leakage currents can flow through the turn-to-turn contact resistance in NI HTS coils. Additionally, screening current-induced voltages become dominant factors during the initial charging process....
No-insulation (NI) high-temperature superconducting (HTS) coils have gained attention for their high overall current density, thermal stability, and mechanical integrity. However, the time constant and the characteristic resistance in NI HTS coils, which are dominantly governed by radial turn-to-turn contact resistances, still require further investigation to examine coil specifications....
To generate the twisted magnetic fields necessary for fusion plasma confinement, stellarators have historically required complex and precise modular coils, which are difficult to manufacture and maintain. In mitigating this challenge, Thea Energy, Inc. is actively developing “Eos”, a planar coil stellarator that can shape the needed magnetic fields using arrays of hundreds of smaller,...
In the development of high-temperature superconductor (HTS) pancake coils, the no-insulation (NI) is a well-known approach that enables self-protection by allowing radial current redistribution during thermal events. This method, while advantageous for mitigating damage during quench, presents significant challenges due to the low contact resistance, which causes a substantial reduction in the...
The no-insulation (NI) winding method is widely known for its ability to improve the stability of high-temperature superconductor (HTS) coils by bypassing the hot spot during a local quench. However, one major drawback of this method is the occurrence of charge and discharge delays due to current leakage between winding turns. To address this limitation, we recently proposed an impregnation...
The contact resistance of non-insulation high-temperature superconducting (NI HTS) coils is an important parameter to characterize their thermal stability. While numerous discharging experiments have demonstrated that the contact resistance of NI HTS coils is not constant, the real-time evaluation of its transient behavior remains insufficiently explored. This paper proposes a novel inverse...
For non-insulated (NI) HTS coils wound with thin REBCO tapes, on the one hand, due to increasing current density, the coils can generate higher magnetic field; on the other hand, the compactness and the mechanical stability of the coils can be improved for the reason of higher proportion of Hastelloy. However, up to now, there is a lack of experimental research data on the electro-thermal...
In the manufacture of Nb3Sn coils, the react-and-wind (R&W) method, which uses heat-treated wire to manufacture coils, has advantages, such as no need for heat treatment of the coil. In the R&W method, it is necessary to consider the degradation of the critical current due to Nb3Sn strain, including strain due to winding. Recently, we demonstrated the fabrication of R&W coils with a small...
The high temperature superconducting (HTS) CORC cable has the advantage of high flexibility, making it one of the best candidate cables for producing compact fusion magnets. The intense background magnetic field strength and high current in the fusion device will cause the CORC cable to be subjected to a huge axial tensile electromagnetic force. Excessive axial tensile load can cause...
CORC® ReBCO cables show great potential as conductors for the next generation of high-performance cables in high-field accelerator magnets. However, due to the unavoidable mechanical stresses present in high-field magnet applications, it is important to investigate the deformation and damage these cables sustain under significant transverse compressive stresses. Our previous study demonstrated...
Complex stress distribution arises in high-temperature superconducting (HTS) coil based on REBCO coated conductors, which is affected by the applied winding tension, thermal stress during cooling down, and electromagnetic forces when energizing the coil. The material and structure of bobbin and overband also play an important role. If the stress exceeds a certain range, it can cause...
In tokamaks, a strong and stable toroidal magnetic field is essential for plasma confinement. Among the available materials for toroidal field coil, REBCO is a promising candidate due to its excellent stability margin and high critical magnetic field. However, the design and analysis of toroidal field coils, which consist of multiple components such as REBCO-coated conductors, solder,...
When designing magnets with strong magnetic fields, it is imperative to consider the mechanical stress induced by the Lorentz force. However, conventional stress-strain calculation methodologies, or force balance equations that utilize the BJR formula, often neglect the frictional force between superconductor tapes. This motivated our previous study on the relationship between the frictional...
The REBCO coated conductor (CC) tapes used in high-field magnets are subjected to a variety of mechanical and thermal loads, including stress during the manufacturing process, Lorentz forces during operation, as well as repeated electromagnetic and thermal cycles. It is crucial for the magnet designers to know the fatigue properties of CC tapes to ascertain their service life under operating...
High-temperature superconducting (HTS) magnets, fabricated by winding HTS tapes, are widely utilized in various advanced applications. During operation, these HTS magnets and their wound HTS tapes are subjected to compressive loads caused by external factors such as winding tension, thermal contraction during cooling, and electromagnetic forces, leading to mechanical deformation. Previously,...
Reinforced BSCCO wire has been considered to have a small margin of strength on the compression side because the filaments has been introduced to compressive strain. However, due to the presence of a sheath and the difficulty of observation, there were no examples of actual fracture behavior in compression. In this paper, we report on in situ microscopic observations of BSCCO filaments exposed...
Designing superconducting magnets presents a challenge due to their inherently multi-faceted nature. It requires a deep understanding of diverse physics domains and the integration of specialized tools. To streamline the design process, CEA-IRFU started developing ALESIA, a novel optimization and data management platform.
Our platform leverages advanced algorithms, including nonlinear...
Superconducting magnets have been extensively studied for their applications in advanced magnetic technologies, taking advantage of their capability to generate high current densities and strong magnetic fields. In the design of superconducting magnets for high field density, a key consideration is the characteristic critical current density, beyond which superconductivity is lost. A previous...
The demand for magnetic resonance imaging (MRI) devices with low cost and reasonable weight continues to increase as applications keep requiring diverse fields of view (FOV). In response to this demand, research on open MRI employing permanent magnets has been actively pursued.
The use of permanent magnets eliminates the need for power consumption and cooling systems, making the setup...
Inspired by the Levitated Dipole Experiment (LDX), Openstar proposed replacing the LTS core magnet with an HTS magnet powered by flux pumps. Embedded flux pumps enable the HTS magnet to maintain a constant DC field similar to LTS magnets with persistent joints. However, due to the limited zero-field region within the magnet, optimizing the flux pump design is critical to achieving maximum...
The simulation of quench dynamics in superconducting magnets is crucial for understanding their thermal and electromagnetic behavior under fault conditions. From a numerical simulation point of view, this is a challenging multiphysics problem involving thermal, electrical and magnetic phenomena. This article presents an advanced application based on ANSYS APDL program developed to simulate the...
Quench detection and protection of high-temperature superconductor (HTS) magnets remain a challenge. Even if the enthalpy margin of HTS conductors is two to three orders of magnitude than low-temperature superconductors (LTS) conductors, a normal zone can be induced by local critical current inhomogeneities or sudden heat load. Because of the high enthalpy and current margins of HTS magnets,...
Detecting quenches in superconducting (SC) magnets during training is a challenging process that involves capturing physical events that occur at different frequencies and appear as various signal features. These events may be correlated across instrumentation type, thermal cycle, and ramp. These events together build a more complete picture of continuous processes occurring in the magnet,...
High-temperature superconducting (HTS) magnets are designated for use as Central Solenoid (CS) magnets in China’s next-generation fusion device. However, their temperature rises rapidly when quenching happens, which may lead to performance degradation. So the voltage detection threshold of HTS is much lower than LTS magnets. The currently employed Co-wound Wire (CWW) + Inductive Noise Realtime...
Superconducting conductors and coils are critical components in high-field applications, requiring rigorous performance evaluation to ensure reliability and efficiency. This paper introduces the design and construction of a superconducting conductor testing apparatus, developed to assess the performance of superconducting conductors and coils under high magnetic fields. The apparatus consists...
Thea Energy has created the “Canis” 3x3 array of high-temperature superconducting (HTS) planar coil magnets as a prototype for the “Eos” stellarator. This poster covers instrumentation of the Canis 3x3 magnet array highlighting the magnetic field control and field validation support systems. Field sensors mounted on each coil combined with individual magnet power supplies allowed the array...
In superconducting applications such as NMR/MRI, SMES, and fusion reactor systems, the critical current (Ic) of the wire is an essential component in determining device performance. This critical current depends on the applied magnetic field (B) and temperature (T), and particularly exhibits magnetic anisotropy in tape-shaped HTS. SuNAM, a manufacturer of HTS wire, operates a 4 Tesla Ic(B, T)...
The large facility under construction at the ENEA Frascati Research Center, named Frascati Coil Cold Test Facility (FCCTF), has been designed with the original purpose of testing the superconducting magnets of the DTT (Divertor Tokamak Test facility) experimental reactor in cold conditions (4.5 K inlet temperature) and high current up to 43 kA. In a 600 m2 large hall, FCCTF will host a large...
In view of the challenges such as small range, low accuracy and weak tracking ability in current measurement of high-temperature superconducting cable for ultra-high field magnets, a high precision and fast response current measurement scheme based on core coil improvement and superconducting coil compensation is proposed. A DCCT high-temperature superconducting compensation coil has been...
Currently, The National High Magnetic Field Laboratory (NHMFL) is in the process of developing a 40 T High Temperature Superconducting (HTS) user magnet, and for the magnet development, it is essential to evaluate the performance of a large number of HTS modules in the future. Typically, each HTS module requires performance evaluation after winding and before being assembled into a magnet....
High-temperature superconducting (HTS) motors have emerged as a compelling alternative to conventional copper-based systems by achieving significantly higher current density and stronger magnetic fields, thereby realizing remarkable increases in torque density. These advantages have spurred intensive research into adopting HTS motors for electric propulsion in aircraft and ships. While...
Characterization of superconducting Rare-Earth Barium Copper oxide (REBCO) tapes is a prerequisite to produce electrotechnical devices such as electromagnets, superconducting fault current limiters or superconducting magnetic energy storage.
The Grenoble applied superconductivity group is developing a high field large bore cryocooled magnet and knowing the critical current Ic everywhere in...
High-temperature superconductors (HTS) have become fundamental materials in modern high-field magnet technology due to their excellent current-carrying capability under strong magnetic fields. The second-generation high-temperature superconductor (2G HTS) ReBCO has the potential to significantly reduce the size and cost of fusion reactors in the field of magnetic confinement fusion, making it...
The accurate measurement of thickness profile across the width of REBCO conductors is critical to design and fabrication of REBCO magnet windings. This is because the non-uniform thickness profile such as so-called ‘dog-bone’ or ‘pillow’ shapes compromise winding’s geometrical integrity, which is especially critical for dry-wound pancake coils. Non-uniform also has significant impact on the...
A concept for a magnetic annealing oven for applications in the fabrication of MRAM and other GMR, TMR effect devices is investigated. With the oven, it is possible to anneal 20 to 50 wafers with a diameter of 200-300 mm at temperatures up to 450°C in a magnetic field of 1 T or more. The magnetic field in this study is created by HTS coils made up of THEVA, SuperOx, Sumitomo and Shanghai...
The large-scale superconducting magnet in controlled nuclear fusion systems and accelerators are key components for achieving high magnetic fields. As a superconducting conductor made from high-temperature superconducting (HTS) tapes, quasi-isotropic strand (Q-IS) exhibits quasi-isotropic properties such as thermal and mechanical stability as well as making it an ideal choice for application...
High-temperature superconducting (HTS) Twisted-Stacked-Tape-Cable (TSTC) conductors have been developed for use in high-field magnets, particularly those needed for compact, high-field fusion tokamaks. TSTC conductors generally contain a large number of simply-stacked RE-Ba2Cu3O7-x (RE=rare earth) (REBCO) coated conductors inserted into helical channels in a round former. Multiple versions...
The integration of high-temperature superconductors (HTS) into fusion coil systems is a key advancement for magnetic confinement fusion technology. HTS conductors provide significant benefits, including higher operational thresholds for temperature, transport current, and magnetic fields, which are pivotal for future fusion applications. A previous study introduced an innovative HTS sector...
Strong magnetic fields might be crucial for enhancing the performance of nuclear fusion devices. High-temperature superconducting (HTS) tapes have emerged as promising materials due to their capability of carrying high current densities in high-magnetic field environments. Alongside with various types of HTS conductors for fusion proposed by numerous research institutions, in our previous...
The slotted core configuration is a promising candidate for the implementation of High-Temperature-Superconducting (HTS) magnets in compact fusion reactors. Quench dynamics is not yet fully understood in this type of cable and experimental and numerical investigations are still required to fully characterize their behavior in the operative conditions relevant to fusion machines.
In this work,...
The complexity of tokamak machines requires virtual alignment studies from the design until the assembly phase. The component variability after manufacturing can cause deviations of the components from their nominal design with consequent installation misalignments. Proper positioning and alignment of the as-built tokamak components, such as magnets, vacuum vessel and in-vessel components, to...
Lanzhou Ion Therapy Company, Ltd. (LANITH) began the research and development of miniaturized heavy ion therapy devices since 2022. The Gantry superconducting magnet, which composed of a curved dipole magnet and two quadrupole magnets at both ends of the dipole coil, is the core component of the whole device. At present, this project has completed manufacturing process for a prototype and a...
The European I.FAST project’s WP8 initiative focuses on advancing Canted Cosine Theta (CCT) magnet technology using High-Temperature Superconductors (HTS). These magnets aim to revolutionize synchrotron and gantry designs by reducing their size and cost, offering transformative potential for research and hadron therapy. HTS materials enable higher magnetic fields and smaller cryogenic systems...
The treatment of cancers with particles is a superior modality compared to a treatment with X-rays. Particles are more effective and treatment is more localized, thereby sparing healthy tissues and reducing the risk of secondary tumors, resulting in an improved quality of life, as well as being the only radiation option for children and infants. Despite the clear advantages of particle therapy...
Superconducting gantries are required to reduce the size and cost of proton or carbon beam delivery systems for cancer radiation treatment. To map out the whole volume of a tumor, a well-focused pencil beam is scanned over the tumor in the two transverse directions while beam penetration and energy deposition in the axial direction is achieved by adjusting the beam energy. To minimize the...
Halbach dipole cylindrical magnets have attracted significant attention due to their ability to generate high magnetic flux density within limited space. However, the end-effect significantly impacts the uniformity of the magnetic field, hindering the application of Halbach dipole arrays, especially in low-field MRI. Currently, most optimization methods focus on adjusting the geometric...
Design, construction, and test of a ~3.8 T, 114 mm aperture dipole based on the Optimum Integral Design using the Direct Wind technology will be presented. This work is being carried by Particle Beam Lasers, Inc. (PBL) and the Brookhaven National Laboratory as a part of the Small Business Technology Transfer (STTR) program. The design significantly reduces the loss of effective length due to...
We are developing an advanced electric propulsion system as a promising solution to achieve carbon-neutral growth in the aviation sector. In a previous study, we successfully developed and tested a 400 kW-class fully superconducting synchronous machine using REBCO racetrack-shaped coils for both the field and armature. The cooling system utilized sub-cooled liquid nitrogen for the armature...
REBCO has been regarded as one of the most promising high temperature superconductor (HTS) options mainly due to its large in-field current carrying capacity and strong substrate mechanical toughness. Thus, it may not be a surprise that the recent high expectation on compact fusion has been largely relying on REBCO conductor and magnet technologies. Despite the recent notable achievements in...
The Magnet Development (MagDev) laboratory at the Paul Scherrer Institute (PSI) has designed and successfully manufactured the first subscale stress-managed common coil magnet. The magnet was tested at CERN and reached 98% of its short sample current. Following the high-field magnet roadmap of the Swiss Accelerator Research and Technology initiative (CHART), a new magnet was assembled after...
The field of electrified aircraft propulsion is undergoing a transformative evolution, driven by breakthrough advancements in superconducting electrical machines. Significant interest exists in the development of closed-loop, rotor-mounted cryocooler superconducting rotors, with several projects pursuing this innovative approach. This design simplifies the cryogenic requirements of...
Our experience with REBCO coils comes primarily from the development of high-field double-pancake/module wound coils for NMR magnet systems. However, many of the conclusions we have reached are quite general. We focus on insulated/insulation coils with a distributed stainless-steel co-wind as the least problematic and thus more promising for our projects, although we also have some experience...
Quench protection of high-field, high-energy-density magnets poses significant challenges. Maintaining the hot-spot temperature and peak voltage-to-ground within acceptable limits requires a protection system that quickly transitions most of the coil turns to the normal state.
Long established magnet protection technologies, such as quench protection heaters or the Coupling Loss Induced...
Most conventional wind power generators need a high amount of rare-earth permanent magnet material (RE-PM).
Gearless low-speed solutions (≈10 rpm) require ≈0.5 ton/MW of RE-PMs. Most work on High-Temperature Superconductors (HTS) in wind power generators has been focused on this type so far and requires high amounts of HTS tapes.
Geared mid-speed solutions (400…600 rpm) need only ≈50 kg/MW...
This presentation aims to provide a concise overview of the current modeling capabilities and highlight critical gaps in simulation and protection strategies for large REBCO coils. High Temperature Superconductors (HTS) are revolutionizing the design of magnetic confinement systems for nuclear fusion and beyond, offering compactness and efficiency through their ability to generate high...
A key focus of the US Magnet Development Program (USMDP) is the development of stress-managed magnets with minimal training and operating near the short sample limit. Training free behavior was previously demonstrated in a paraffin-wax-impregnated subscale (canted-cosine-theta) CCT dipole as part of the CCT subscale magnet program at Lawrence Berkeley National Laboratory. A subsequent...
Hyper Tech Research will report on progress that has been made on developing high purity aluminum (HPAL) and magnesium diboride superconductor wires, cables and coils with significantly lower AC losses. The use of HPAL low AC loss stands will enable high power density motors and generators in the 35-45 kW/kg range, with efficiencies in the range of 99%. HPAL low AC loss coils for stators can...
The BigBOX experiment aims to assess the training performance and robustness of paraffin-wax impregnated Nb3Sn coils under high Lorentz forces. The results of the experiment are the product of a collaborative effort between the Swiss Accelerator Research and Technology initiative (CHART) at the Paul Scherrer Institute (PSI) and Brookhaven National Laboratory (BNL). The experiment involves the...
Higher field, much lighter-weight and more efficient ac magnets that can operate at affordably cooled temperatures above 12 K require HTS. Stator coils for example operate in fast AC modes where HTS tapes cannot be used due to excessive induction-driven losses, requiring instead HTS as small cross-sectioned, fine-filament, axially twisted wires in transposed cable forms. An approach has been...
Non-insulated (NI) magnets made of rare-earth barium copper oxide (REBCO) high-temperature superconducting tapes are of interest for a variety of different magnet applications, such as in the toroidal field magnets of fusion devices. One of the primary reasons for this is the potential ability for NI coils to passively protect themselves against damage during a rapid global loss of...
This talk provides an overview of several protection concepts and simulation tools, specific to REBCO coils, that are currently under development within the TE-MPE group at CERN. Capacitive discharge and more efficient variants of the Coupling Loss Induced Quench method will be presented as promising new protection methods. While simulation tools for LTS magnets are well developed and...
As part of the US Magnet Development Program, Lawrence Berkeley National Laboratory (LBNL) is developing high field stress-managed Nb3Sn dipole magnets using canted-cosine-theta (CCT) technology. A series of epoxy two-layer magnets, CCT3/4/5, with short sample bore field of approximately 10 T and a 90 mm diameter open aperture have been designed, fabricated, and tested. The third and final...
Offshore wind power generation is pivotal for the decarbonization of the energy sector, with projections indicating that installed capacity could exceed 200 GW by 2030. As turbine size and power ratings increase, the industry encounters challenges concerning components such as blades, structures, and generators. Partially superconducting generators (SCGs) (superconducting field, normally...
Accelerator magnets based on high-temperature superconductors will be fundamental to producing a field in excess of 16 T for future HEP machines. One of the known challenges of practical conductors made with HTS materials is a slow normal zone propagation resulting from a large superconducting temperature margin in combination with a higher heat capacity compared to conventional...
This paper presents the measurement results of the Triplet magnets assemblies for the Swiss Light Source (SLS) 2.0 upgrade. Emphasises is given to the measurement challenges related to the tuning process of those magnets guarantying the production quality. The complete renewal of the SLS storage ring (SLS 2.0) relies on the longitudinal gradient bend (LGB) function, implemented by a Triplet,...
Recently, due to the electrification of mobility systems such as aircraft and ships, the development of high power density propulsion systems has been actively researched. In conventional electric machines based on permanent magnets and copper, the power density is limited due to constraints in current density and magnetic field. As an alternative, high-temperature superconducting (HTS)...
Since commissioning in 2022, the Facility for Rare Isotope Beams (FRIB) has successfully delivered over 270 rare isotope beams, including the discovery of five new rare isotopes. To fully leverage the scientific potential of FRIB, a new High Rigidity Spectrometer (HRS) has been proposed to overcome the limitations of the existing Spectrometer of S800, the legacy from the NSCL era.
The HRS...
Bi:2212 is a well-known high current superconductor which can be made in round wire form. It has usually been of interest for DC or low ramp applications because of both filament bridging and also a high Ag content which encourages large coupling and eddy current losses. However, a new low loss Bi:2212 has been under development which both attempts to suppress the bridging as well as eddy and...
The Oak Ridge National Laboratory STS Project will enhance the Spallation Neutron Source by adding a new neutron source. The upgrade includes a 30% increase in beam energy and a 50% boost in beam current, doubling the accelerator's power capability to 2.8 MW. The Ring-to-Second-Target Beam Transport (RTST) system is vital in directing high-energy proton beams to the target. A key element of...
A new eddy current septum for the fast extraction from CERN’s Proton Synchrotron has been designed and constructed. This development aims to improve the magnet's reliability, extend its service interval, and reduce radiation exposure for maintenance personnel. The new eddy current device is set to replace the existing direct-drive magnet and its ageing power converter.
This paper summarizes...
The Interaction Regions (IR) for the FCC-ee collider as envisioned by the CERN FCC Feasibility Study requires a variety of superconducting correction coils that must be integrated with the main IR focusing quadrupoles. The present technological basis for these main quadrupoles is to wind superconductor supported in side-by-side slotted tubes, located deep inside the experimental detector...
The report will explore the societal context of the major turning points in the application of superconductivity that have been crucial for the development of magnet technology. This is relevant in that we are now at a point where a further breakthrough is necessary to enable the development of affordable high field magnets (16 to 20 tesla dipoles), appropriate for series production and...
Cable-In-Conduit-Conductor (CICC) is particularly suitable for applications requiring both high magnetic fields and efficient current transmission, such as in particle accelerators, magnetic resonance imaging (MRI) systems, and high-field magnets. To further enhance the current-carrying capability of CICC, we developed a CICC conductor in which the CORC strands are made up of 24 layers, with a...
Study on Quench Behavior in Aluminum stabilized Stacked REBCO Tapes Cable
The Circular Electron Positron Collider (CEPC) is a significant international scientific facility proposed by the Chinese particle physics community in 2012. Its main objective is to conduct detailed measurements of the properties of the Higgs boson. The latest conceptual design of the CEPC detector magnet has...
In order to satisfy the magnetic requirements of high current, high-field and excellent mechanical properties of magnet systems in future fusion devices, a compact high-current-carrying conductor structure inspired by quasi-isotropic strand (QIS) and twisted stacked tape cable (TSTC) structures is proposed in this paper. By placing three groups of equal volume but different direction HTS...
In a superconducting cable, in which element superconductors often called strands are assembled to increase current-carrying capacity, current distributions among strands impact its performance. Here, we focus on cables in which coated conductors are wound spirally on their cores such as CORC cables and SCSC cable. In this presentation, such a cable is called spiral-coated-conductor cable as a...
The Superconducting Magnet Group of the Institute High Energy Physics, Chinese Academy of Sciences, is investigating a dipole magnet fabricated with Nb3Sn and HTS to achieve a field of 15-20 T or even more higher. A compact high current carrying compacity and low AC loss ReBCO cable (X-cable) is developed for the insert HTS coil. The structure of the cable is similar to the original Roebel...
We have been developing the SCSC cable (Spiral Copper-Plated Striated Coated-Conductor Cable) consisting of copper-plated striated (multifilament) coated conductors wound spirally around a round core. Its spiral geometry decouples filaments electromagnetically against transverse magnetic fields like twisted low Tc superconductor wire and, then, reduces AC loss. The copper helps current sharing...
Limited by filament size, the dimensions of Rare-earth Barium Copper Oxide (ReBCO) cables are usually comparable to the width of the constitutive tape strands. Resultantly, the distribution and redistribution of currents amongst strands can have a strong impact on the behaviors of the cable, including current-voltage characteristics and in-field performance. In this study, we present a...
The development of high-current cables made of rare-earth barium copper oxide (REBCO) coated conductors is a key technology for high-field accelerator magnets above 16 T. A flexible round REBCO cable has been proposed as one of the candidates for the high-current cable. This round REBCO cable consists of many coated conductors wound in multiple layers in a helical configuration on a metal...
This paper proposes a novel approach to enhance both the engineering current density and the uniform distribution of the magnetic field in a high-temperature superconducting (HTS) strand. This is achieved by weaving the strand using transpositional REBCO tapes. The H formula is utilized to establish a three-dimensional (3D) Finite Element Model (FEM) in the proposed approach. In the proposed...
Self-shielding high-temperature superconducting (HTS) DC cables made of REBCO tapes can almost eliminate the magnetic field within the cable layers, greatly improving the uniformity of current and magnetic-field distributions. In this paper, based on the H-equation and the circuit model of the cable, the current evolutions in two self-shielding HTS DC cables made of REBCO tapes with different...
One of the greatest challenges in designing the superconducting field winding for a superconducting generator (SCG) is balancing mechanical loads while limiting heat that can enter via mechanical structure. This paper outlines the thermal and mechanical co-design of the field coils for a low speed, high torque, partially superconducting generator using LTS wire. Mechanical design is focused...
Magnetic drive is a technology that utilizes magnetic force to achieve non-contact driving, which has advantages such as high efficiency, reliability, and environmental protection. It can meet the needs of different working conditions and has important application prospects. Due to the lack of disconnection function in magnetic drives, we conducted researches on magnetic drivers based on...
With the growing prevalence of electrical propulsion technology in aerospace and new energy applications, high-temperature superconducting (HTS) motors have garnered substantial interest due to their high efficiency and power density. Among these, axial flux motors (AFMs) stand out for their compact design and superior efficiency, positioning them as a promising candidate for future electrical...
High-purity aluminum armatures present a viable alternative to traditional superconducting armatures, which can face quench issues during AC operation despite their high-power density. Leveraging the low electrical resistance and lightweight properties of high-purity aluminum at cryogenic temperatures, this study presents the development of an armature for a 500 kW partially superconducting...
High temperature superconducting materials are commonly used in permanent magnet motors for stator armature windings, which can increase the power density of the motor. The use of ferromagnetic materials in the stator reduces the magnetic field in the superconducting coil, which increases the current carrying capacity of the superconducting coil. The rotor uses permanent magnets for...
Axial-flux permanent magnet (AFPM) motors have gained significant attention in industries such as electric vehicles and ships due to their compact size, high torque density, and superior efficiency. While various AFPM designs have been proposed, this study focuses on the yokeless and concentrated armature structure, which offers unique advantages by eliminating the stator yoke. This reduces...
Using a superconducting bulk into the rotor enables torque generation by inducing current through an external armature, similar to the principle of an induction motor, without the need for direct current application to the rotor. This topology can reduce rotor resistance losses compared to conventional induction motors due to the low resistance of the superconducting material. Moreover, this...
Introduction
A torque tube with a low heat-conduction spoke torque tube was introduced in an earlier study. This study explores the characteristics and design trade-offs of this topology using a combination of analytical models and experimental validation. Results indicate that the spoke-supported topology generally favors small diameters due to its negligible heat leakage. Additionally,...
In the design of ultrahigh field magnetic resonance imaging (MRI) superconducting magnets, it typically requires a high homogeneous magnetic field in the diameter of spherical volume (DSV) to obtain high quality image. Spherical harmonic based B0 shimming relies significantly on the fitting process, which can be computationally demanding, especially when handling a large number of shim coils....
For magnets requiring high uniformity, such as those used in MRI and NMR, shimming techniques are applied to correct the magnetic field distribution. These shimming techniques can be divided into two types: shim coils that are powered with current, referred to as active shimming, and iron shims that do not require current, referred to as passive shimming. In active shimming, superconducting...
“Eos”, Thea Energy, Inc.’s first integrated fusion system, will utilize arrays of small, optimized planar coils that help to mitigate manufacturing complexity found in prior generations of the stellarator. To properly shape the magnetic fields necessary for plasma confinement, Eos will require hundreds of these planar coils; Thea Energy’s ability to reliably and quickly produce them will be...
A high-sensitivity inductive coil for detecting the Haas-van Alphen oscillations of magnetic materials or calibrating magnetic field was fabricated. The coil contains part A and part B which are well compensated in applied external fields with opposite winding directions. Fabrication of a high density (>1000 turns) pick-up coil within a small sample space (diameter~3mm) is challenging....
The background magnets of the superconducting conductor test facility (Super-X) are composed of CICC-wound superconducting coils, weighing approximately 100 tons, and are actively cooled using supercritical helium. During the cooling process, fluctuations in the chiller's power and the complexity of heat transfer may cause deviations from the designed cooling process. These factors hinder the...
The analysis and calculation of magnetic fields serve as the cornerstone for magnet design. In scenarios requiring intricate spatial magnetic field configuration optimization, high-throughput analytical computations are often necessary, posing significant computational cost challenges to existing finite element method (FEM)-based approaches. In recent years, surrogate model computations...
High-temperature superconducting (HTS) generators cooled by liquid hydrogen are being researched and developed, with a 6kA-class assembled conductor required to superconduct the field winding of a 600 MW-class generator. The development target was a conductor consisting of 9 HTS wires in a thiree-layer structure with a 5 mm diameter former. To verify the current capacity of the assembled...
The development of multi-filamentary high-temperature superconducting (HTS) tape represents a significant research direction for the advancement of future applications, largely due to its lower AC loss. The AC loss characteristics of the multi-filamentary structure have been the subject of extensive experimental and finite element simulation studies. Nevertheless, there remains a research gap...
High-temperature superconducting (HTS) coils are widely utilized in magnet applications due to their superior performance in compactness and energy efficiency. Traditionally, the critical current (Ic) of HTS coils has been measured using the 100 μV/m criterion, adopted from the international standard for second-generation HTS wires. However, as discussed in previous research, this criterion...
Under pulsed high magnetic fields, the interaction between the magnetic field and the spin of a material provides a unique opportunity to explore various magnetic properties, such as magnetization, dielectric polarization, and magnetostriction. These properties are critical for characterizing the diverse phase transitions that materials undergo. Among the measurement techniques available,...
Openstar Technologies is advancing the Levitated Dipole fusion reactor concept. OpenStar’s first experiment, ‘Junior’ retired engineering risk and matched performance of similar experiments elsewhere. The next experiment, Tahi, will enable new fusion science and produce a triple product greater than 1e19 [keVm-3s]. Magnetic confinement for this experiment is provided by the Tahi Core Magnet -...
OpenStar Technologies Ltd is pursuing a levitating dipole reactor (LDR) for fusion energy production. As part of the first LDR prototype, a 5.6 T, 1.44 kA HTS magnet, Junior, has been successfully designed, built and tested.
Junior consists of 14 non-insulated (NI), solder impregnated HTS coils connected in series. Coil parameters such as radial resistance and joint resistances are...
Commonwealth Fusion Systems (CFS) completed the design, construction, assembly, and full field dual magnet factory acceptance testing of two identical compact (< 2 ton), high-field (20 T on tape, 17 T in warm bore) HTS REBCO magnets for a magnetic mirror in an axial fusion device. The CFS magnets now serve as the high field end coils for the ARPA-E funded project, “An HTS Axisymmetric Magnetic...
Startup and quench behavior in a FNSF scale Toroidal Field (TF) HTS magnet were explored in a previous ASC paper. In that study a mix of superconducting and resistive materials are
arrayed in a Bitter Plate like arrangement. In the studies presented here, various quench mitigation scenarios are explored. The conductor arrangement is a parallel set of HTS channels with radially...
Stellarators confine plasma in a stable toroidal configuration using twisted external magnetic fields. However, this requires complex 3D coil shapes that can pose a significant design, manufacturing, and maintenance challenge. To address this challenge, Thea Energy, Inc. is developing the planar coil stellarator. This approach utilizies multiple smaller, individually energized coils that...
After the first plasma in 2006, the Experimental Advanced Superconducting Tokamak (EAST) is approaching now 20 years of operation. It has been the first tokamak featuring both toroidal and poloidal superconducting coils. In particular, its toroidal field (TF) magnet system is composed by 16 coils with an height of about 4 m.
The superconducting coils are operated at a temperature of 4.5 K,...
Conventional high-field pulsed magnets employ layered reinforcement techniques, where high-strength fiber composites are inserted around each conductor layer within solenoid coils to withstand the substantial Lorentz forces. For magnets exceeding 80 T, the required reinforcement layer thickness exceeds 5 mm. However, this design reduces the conductor filling factor and increases the coil...
Accelerating the cooling rate of pulsed magnets has a significant impact on the efficiency of physics experiments. Inserting axial liquid nitrogen cooling channels in the magnet is a common method to accelerate the cooling rate. However, the cooling channels prevent stress from being transmitted between the layers of the magnet, which reduces the structural strength and increases the design...
Cu-based composites with high strength and electrical conductivity are core conductor materials for high-field pulsed magnets. High-performance composite wires have been well developed by Northwest Institute for Non-ferrous Metal Research (NIN), such as Cu-Nb and Cu-Ta materials. In this study, the jelly-roll + accumulative drawing and bundling (ADB) process has been inventively applied for...
Copper-based conductive wires with both a high strength and a high electrical conductivity could find applications in aerospace and power engineering as well as in niche scientific applications such as materials for the production of high-field pulsed magnets. Indeed, in order to produce non-destructive fields, the coils must be wound of wires with a very high mechanical strength to resist...
MegaGauss facilities provide a unique environment to study materials under extreme conditions. This not only concerns samples exposed to the magnetic field in the center of a coil, but also the coil itself. The present study focuses on the deformation of copper single-turn coils (STC), specifically analyzing the impact on the material microstructure. While generating the field, STC undergo...
Single-turn coil (STC) is a destructive pulsed magnet aiming at high magnetic field beyond 100 T. To increase the peak magnetic field, delay the destruction of conductor, and avoid the damage of samples, it is important to select the thickness of STC appropriately. If the conductor is too thin, the temperature rise and deformation of the coil during discharge can be so drastic that the coil...
Single-turn coil (STC) is a kind of destructive pulsed magnet with the peak magnetic field higher than 100 T. Due to the extremely high current rising rate and peak discharge current, gas switches are often used to control the parallel discharge of multiple capacitors. However, gas switches generally have long jitter times and their triggering is difficult to maintain a high degree of...
Single-turn coil (STC) is a mainstream destructive pulsed magnet used to generate ultra-high magnetic field beyond 100 T. During the discharge process, STC is in extreme physical states with extremely high pressure and high strain rate deformation, leading to fracture and explosion of the coil. This study investigates the damage and destruction process of STC using three-dimensional finite...
Single-turn coil (STC) is a type of destructive pulsed magnet used to generate ultra-high magnetic fields ranging from 100 T to 300 T. In this study, a three-dimensional finite element simulation model of the STC is established, and the electric field distribution properties with different coil sizes and power excitations are investigated to assess the possibility of radial electric breakdown...
Magnet Cold Test Bench (MCTB) is a test facility under development to test the superconducting Toroidal Field (TF) and Poloidal Field (PF-1) magnets at ITER. The testing of the magnets will be performed at 4K cryogenic temperature. The cryostat is required for housing the TF and PF-1 magnets in the vacuum environment for test at cryogenic temperature.
The material of construction for the...
In the framework of the Future Circular Collider (FCC) study at CERN, a conceptual design of a cooling scheme for Nb$_3$Sn-based accelerator magnets operating at 4.5 K is proposed for the FCC-hh (hadron) configuration. This alternative, at a higher operating temperature than the baseline at 1.9 K using Helium II, is motivated by a strong commitment to a more energetically...
Multi-Layer Insulation (MLI) is widely used in cryogenic systems to effectively suppress radiation due to temperature differences. In particular, MLI plays a crucial role in reducing cooling energy consumption and maintaining the thermal stability of superconducting coils in superconducting magnet systems. High-field superconducting magnets require cryogenic environments to sustain high...
A comprehensive thermohydraulic analysis was conducted on a conduction cooled demonstrator coil operating at 20K. The primary objective was to assess potential cooling options for High-Temperature Superconducting (HTS) magnets intended for fusion energy applications. The entire process involved the design, manufacturing, and testing of a 0.2mx0.3m demonstrator coil in a vacuum environment. The...
A demonstrative NbTi based Mixed Axial and Radial field System (MARS-D) is being developed for a next-Generation Electron Cyclotron Resonance Ion Source (ECRIS) at Lawrence Berkeley National Laboratory, which employs a novel closed-loop coil design scheme that more efficiently utilizes conductor fields and extend the application of NbTi for high frequency (up to 45 GHz) ECR operation. The NbTi...
Superconducting magnets serve as pivotal components in advanced rail transportation, next-generation power systems, Magnetic Confinement Fusion, and other critical infrastructure. They find extensive applications across various sectors including industry, energy, medicine, large scientific apparatuses, and semiconductors. Superconducting magnets are typically cooled through coolant immersion...
Several new controlled nuclear fusion systems are under development in China. To achieve the higher magnetic field intensity and to minimize the final size as well, the high-Tc superconducting magnets are adopted. There are a variety of rigorous requirements on the associated cryogenic system expected to provide 600 W at around 20 K, of which high-efficiency and high-reliability are especially...
Rare Isotope Accelerator Complex for ON-line experiments (RAON) is the first heavy ion accelerator facility in South Korea. RAON consists of two main superconducting linear accelerators: SCL2 and SCL3. SCL3 cryogenic system was successfully completed the cryogenic commissioning in 2022 and maintained the stable cryogenic environment for the first beam commissioning in 2023. However, SCL2-IF...
Cryogenic Permanent Magnet Undulator (CPMU) is an important kind of insert device at the synchrotron radiation facilities. The magnets of CPMU have a better magnetic performance than a conventional In-vacuum Undulator. The work temperature of CPMU magnets in C11 CPMU is below 80K. The cryogenic operation of CPMU requires a sub-cooled liquid nitrogen cooling system. The operational stability of...
To generate a magnetic field exceeding 20 T, high-temperature superconductors (HTS) are essential. This study focuses on the conduction cooling experiments of high-temperature superconducting magnets capable of generating a 20 T magnetic field. This magnet is designed to operate at temperatures up to 20 K using hybrid HTS tapes, and the room temperature bore is 50 mm. To solve mechanical and...
We have developed a robotic winding machine for manufacturing saddle-shaped HTS coils applicable to accelerators, motors, and MRIs. This winding machine is designed to wind HTS saddle coils with a maximum length of 50 cm and a maximum diameter of 10 cm based on a cylindrical bobbin. A 5-axis robotic arm moves to position the spooling wire accurately. After constructing the winding machine, we...
High-temperature superconducting (HTS) motors and generators utilizing HTS magnets exhibit exceptional energy efficiency and output performance due to their high current density. In these systems, maintaining the rotating HTS magnets at cryogenic operating temperatures is crucial. Specifically, the rotor requires a thermal coupling structure to enable cryogenic cooling between the stationary...
High-temperature superconducting (HTS) motors have broad application prospects in fields such as energy and transportation due to their high efficiency and energy-saving characteristics. However, the vacuum and low-temperature conditions in their operating environment impose stringent requirements on sealing technology. This study addresses the sealing demands of HTS motors by designing a...
Over the past few years, significant advancements have been made in superconducting technologies, particularly in the performance and supply of low- and high-temperature superconductors, cryogenics, and system integration. These developments are now ready for scaling up and deployment in a wide range of applications beyond their current uses, such as MRI, NMR, and various fields in physical...
Superconducting magnets are the critical differentiating technology of superconducting rotating machines. High Temperature Superconducting (HTS) rotating machines will revolutionize aero-propulsion aviation, ship propulsion, power generation, industrial motors, and many other applications by providing unmatched efficiency and power density. This panel discussion will focus on the latest...
The test facility dipole magnet (TFD) is being developed at the Lawrence Berkeley National Laboratory (LBNL). This is a large-bore Nb$_3$Sn dipole magnet to be at the center of the High Field Vertical Magnet Test Facility (HFVMTF), funded by the U.S. Department of Energy (DOE) Office of Science (SC), and designed to test advanced cables and inserts in a high transverse background field and in...
High magnetic fields of up to 20 T in tokamak-type fusion devices require High-Temperature Superconductors (HTS) and 50 kA/20 T class, full-size ReBCO Cable In Conduit Conductors (CICC). Conductors based on Conductor On Round Core (CORC®/HFRC) cables, are among others, proposed for the Central Solenoids of the European DEMO and the Chinese BEST fusion reactors. The large Lorentz forces...
This presentation summarizes the development and testing progress of a 100 kW superconducting propulsion unit designed for zero-emission aviation. The findings draw from two major UK-funded projects, in collaboration with Airbus Upnext. The propulsion unit features an axial-flux fully superconducting motor and an integrated cryogenic drive system. The motor, comprising two HTS stators and one...
Consideration of screening current induced stress (SCIS) is crucial for management of stress and strain in the design of ultra-high field REBCO magnets. We developed a numerical simulation tool that utilizes COMSOL and studied the effects of including reinforcement in REBCO coils such as co-winding or over-banding steel tapes [1]. The model employs the penalty method as a boundary condition...
The Falcon D (Future Accelerator post- LHC Cos-theta Optimised Nb3Sn dipole) dipole is part of the High Field Magnet (HFM) program. CERN in collaboration with the Italian Institute for Nuclear Physics (INFN Genova and LASA Milano), is developing the design of cos theta dipole magnet beyond 11T based on proven Nb3Sn technology in the MQXF quadrupoles used in the high-luminosity upgrade of the...
Conductor on Round Core (CORC®) cables, consisting of REBCO coated tapes helically wound around a metal former, are a promising conductor option for future high-field dipole magnets in particle accelerators. Crucial to the success of this application is the conductor resilience to mechanical loads. The promising electrical performance of the CORC® wires may be compromised by damage and...
Investigations carried out up to now on superconducting Maglev trains have always planned to use YBCO or REBCO oxides as superconducting materials [1, 2]. While MgB2 enters more and more applications [3], bulk MgB2 has not yet been seriously considered for Maglev projects. Its main drawback is its Tc that is low as compared to that of HTS oxides. As a consequence, the cooling costs are assumed...
Rare-earth barium copper oxide (REBCO) coated conductors (CCs), the leading candidates for the construction of ultra-high field magnets, are produced in the form of thin tapes, with a laminar structure consisting of different layers of functional materials. The feeble adhesion strength between layers has been long remarked, and represents a major concern for magnet design, as it imposes hard...
With current propulsion capabilities, the trip to Mars takes around 6 to 8 months during which astronauts, plants, seeds, and electronics are exposed to energetic cosmic rays and solar flares that exceed acceptable radiation limits. This presents a critical challenge for future human interplanetary missions. In this work, we present a conceptual design for an innovative dual-purpose system...
The High Field Magnet (HFM) R&D program at CERN aims to find technological solutions for the construction of accelerator magnets to be installed in future post-LHC colliders. The Italian Institute of Nuclear Physics (INFN) and CERN are collaborating to design and fabricate a new four-layer Nb3Sn cos-theta dipole able to achieve a bore field of 14 T with at least 20% of margin on the loadline....
This study investigates the delamination behavior of REBCO coated conductors (CCs) using the electromagnetic delamination strength (EDS) method. Unlike the mechanical delamination strength (MDS), which relates stress to structural failure, EDS focuses on the irreversible threshold at which critical current degradation occurs. This distinction is particularly important for high-field magnet...
CEA Paris-Saclay is developing, in collaboration with CERN, the R2D2 (Research Racetrack Dipole Demonstrator) magnet. The main goal is to demonstrate the feasibility of key technologies for future high field 16 T $Nb_3Sn$ magnets for particle colliders. On one hand, the coil manufacturing has been finalized and four coils have been produced. First, two practice coils have been manufactured,...
The delamination problem of the epoxy-impregnated REBCO coils was always an obstacle for REBCO magnet application. To avoid the delamination, recently a novel method that coating release agent layers on the REBCO tapes was proposed, and it has been preliminarily verified by REBCO coils impregnated room-temperature curing epoxy (Stycast 2850). For thermosetting epoxy, like IR3 (supplied by...
No-insulation (NI) coils are known for their high thermal stability and self-protecting features due to turn-to-turn contacts. Parallel co-winding is a promising method to reduce the charging delay of NI coils while maintaining thermal stability. This technique shows significant potential for applications in fusion and other large-scale or high-field magnets. In parallel co-wound NI coils, the...
The Small Test Coil (STC) magnet testbed using a REBCO coil and a 15 T background magnet was designed to answer key issues in high-field, high-stress superconducting magnet technology. Recent STC revisited screening current stress (SCS) and subsequent conductor damage issues, and concluded the limit of the full elastic deformation assumptions for accurate SCS calculations and conductor damage...
No-insulation REBCO (NI-REBCO) coils, with self-protecting capabilities during quench, have attracted significant interest and shown considerable potential for high-field applications. As research advances, it has become increasingly evident that uneven stress/strain induced by screening currents is a critical factor affecting the performance of NI-REBCO coils. Therefore, reducing...
High Temperature Superconducting (HTS) No-Insulation (NI) coil has broad applications in high field magnets due to its excellent stability. The turn-to-turn resistance, which is related to winding stress, is an essential parameter for NI coil. However, the turn-to-turn resistance is non-uniform in radial direction for present winding method. Thus, the voltage response is also non-uniform. In...
No-insulated high temperature superconducting (HTS) coils are widely favored for high engineering current density and self-protection properties. Radial stress is an important parameter for HTS coils, which is mainly the superposition of winding tension, electromagnetic load and thermal stress. Radial stress is related to the magnet transient behavior and the self-protection characteristics of...
Due to the increasing interest in nuclear fusion, basic plasma experiments/small scale devices are good to illustrate plasma physics properties like magnetic surfaces and/or the importance of it. The construction of a table-top stellarator experiment, referred to as Polaris, is envisaged for the Swiss Plasma Center of EPFL. Polaris (major radius ~40cm and minor radius ~15cm) consists...
Many studies have focused on different types of no-insulation (NI) high-temperature superconducting (HTS) magnets. In particular, REBCO-based NI magnets have been explored in various forms, including conventional no-insulation magnets with copper stabilizers, cladding methods where high-resistance metals or semiconducting materials are coated on REBCO tapes, and co-winding methods where REBCO...
No-Insulation (NI) coil utilizing HTS tape conductor has become a promising option for high-field magnets, capable of delivering both excellent thermal stability and high current density. NI coil can reduce heat generation due to a current behavior that bypasses the defect when a local hot-spot is formed in HTS tape conductor. In the high-field magnet application, a coil structure with large...
The estimation of critical current ($I_c$) and the index value for single-tape wound coils and magnets is relatively straightforward. However, for multi-tape co-wound coils, the process becomes complex due to various factors influencing current distribution within the coil. This study conducts a numerical analysis to explore these factors and their impact on the $I_c$ and index value of...
Since there’s a huge travel speed gap between airplanes (900km/h) and high-speed trains (300km/h), maglev trains (400~1000km/h) now seem having an extensive development space. The performance of the maglev rail is an important factor which limits the development of maglev trains. Conventional maglev magnetic rails mainly adopt the scheme using equidistant permanent magnets(PMs), while the more...
The increasing use of Rare-earth barium copper oxide (REBCO) bulks in electromechanical applications, particularly for acting as “pseudo” permanent magnets, is driving the development of more sophisticated numerical models. The focus has been on modeling electromagnetic phenomena with greater accuracy and efficiency, taking into account the non-linear and heterogeneous characteristics of high...
In the melt heat treatment process for growing YBaCuO superconducting single crystals, increasing the distribution density of flux-pinning particles, Y2BaCuO5, is critical. The flux-pinning effect occurs at the interface between Y2BaCuO5 and YBa2Cu3O7, so a Y1.6Ba2.3Cu3.3O7-y bulk was fabricated to enhance Y2BaCuO5 concentration and improve oxygen diffusion during growth. However, the high...
High-temperature superconducting (HTS) bulks can exhibit superconducting properties at liquid nitrogen temperature. As a type-II superconductor, these materials demonstrate flux pinning effects, wherein magnetic flux is pinned inside the superconductor when the external magnetic field exceeds its lower critical field. This phenomenon imparts permanent magnet characteristics to the material,...
A superconducting bulk magnet can generate a strong magnetic field in a compact and lightweight device. Among magnetization methods for bulk magnets, pulsed-field magnetization (PFM) is effective for industrial applications because a bulk can be excited on-site in a short time. In terms of the generated magnetic field, it is reported that almost 100% of the sample's field trapping performance...
Magnetic Resonance Imaging (MRI) is a technique that generates high-resolution volumetric images of the body using a strong magnetic flux density. The image quality directly depends on the magnetic field homogeneity. Commercial superconducting magnets have a magnetic field homogeneity below two parts per million (ppm) and use Nb-Ti magnets. However, they need to be cooled at 4 K. It is costly...
The conventional iron matrix shimming method is sensitive to positional variations, which significantly impacts the magnetic field homogeneity of small-aperture 7T/54mm cryogen-free MRI superconducting magnets. This study aims to develop a robust, adjustable shimming method to improve magnetic field uniformity and precisely cancel low-order harmonics in these sensitive systems. A set of...
The Brazilian Center for Research in Energy and Materials (CNPEM) has built a medium field Magnetic Resonance Image (MRI) prototype as part of an overall effort on the in-house development of fundamental MRI technology know-how. The system is comprised of a permanent-magnet-based dipole, a set of planar coils for gradient field generation and a radiofrequency system with a...
In this paper, we present the design and test results of a low-AC-loss Nb3Sn model coil developed to validate key enabling technologies for a fast-switching-field magnetic resonance imaging (MRI) magnet concept that can change the magnetic field very quickly in time, within 1 second, between significantly different field strengths: a high field (3 T) for relaxometry and prepolarization and a...
Superconducting joints play a very important role in the superconducting magnet of any Magnetic Resonance Imaging (MRI) scanner. The multi-coil superconducting magnet is the heart of any MRI machine. The superconducting magnet in MRI needs to generate a highly homogenous magnetic field (± 5ppm) and high field stability (<0.1 ppm/hr) in its imaging volume to ensure a consistent and clear image....
A low-cryogen compact 7T MRI system(C7T) dedicated for brain imaging has been developed at the GE HealthCare Technology and Innovation Center. The C7T magnet utilizes a fully sealed helium cooling system. Only 12 liters of liquid helium are condensed at 4.2 K from high pressure gaseous helium charged at room temperature. The C7T magnet is designed for a B0-field homogeneity <1.0 ppm in a 26-cm...
Abstract：High field magnetic resonance imaging (HF-MRI) systems can achieve higher image resolution and sensitivity, resulting in better image quality and more biological information, which has significant value in life science and clinical medicine applications. The key to high field magnetic resonance imaging systems is the high homogeneous superconducting magnets, and active homogenization...
In this paper, we present the finalized design, construction, and test results of a cryogen-free, iron-shielded 23.5-T/28-mm room-temperature bore REBCO magnet, developed for use in benchtop 1-GHz microcoil NMR spectroscopy. This benchtop magnet is composed entirely of REBCO conductors and operates at ~10 K in a conduction-cooled cryostat, featuring an external iron cylinder outside the vacuum...
Accurate magnetic field correction is essential in MR applications to achieve high field homogeneity and reduce manufacturing complexities. This study proposes an adaptive shim design method that leverages recursive linear programming for efficient optimization of shim configurations. Conventional nonlinear optimization approaches, such as Sequential Quadratic Programming (SQP), often result...
The Halbach magnets are assembled from multiple magnetic pole modules according to certain rules. Due to its small size, it can be made into desktop magnetic resonance equipment and have wide applications in food composition testing and chemical composition detection areas. Because of the use of permanent magnetic materials and assembly processes, the magnetic field uniformity of Halbach is...
Building upon the successful development of 26.86 T @ 30 mm and 16.6 T @ 100 mm fully REBCO high temperature superconducting (HTS) magnets, we have initiated the research and development of an 800 MHz NMR magnet with a 54 mm room-temperature bore. High-field HTS magnets face significant challenges during operation, such as pronounced screening current effects, which lead to poor magnetic field...
Extremely high field NMR magnets have received much attention by improved resolution and higher sensitivity. However, one of the main reasons limiting its development is the magnetic field inhomogeneities generated by high-temperature superconducting (HTS) magnets cannot be compensated by conventional superconducting and room temperature shim coils. The design, fabrication, and testing results...
We have been conducting the basic design, fabrication, and testing of a joint-less high-temperature superconducting (HTS) magnet operating in persistent current mode using second-generation HTS conductors. The joint-less winding method is typically used to produce double pancake coils, but for magnet applications, multiple coils must be stacked. However, the inherent characteristics of the...
The extremely high magnetic fields offer significant advantages in improving imaging quality and analyzing the fine structures of materials. However, these benefits critically depend on achieving high levels of B0 magnetic field homogeneity. This necessitates the development of advanced shimming technologies, which can be effectively realized using superconducting shim coils. This paper...
A 9.4 T cryogen-free system developed by Cryogenic Limited has been used for the high resolution solid-state magic angle spinning (MAS) and liquid-state NMR experiments. The temporal magnetic field distortion due to the cold head operation was 2 Hz peak-to-peak on the resonance frequency 400 MHz [1]. This distortion occurred at the frequency of 1.7 Hz in our experimental setup.
In...
The Electron-Ion Collider (EIC), hosted by Brookhaven National Laboratory, is designed to deliver a peak luminosity of 10^34 cm−2 s−1. The interaction region (IR) of EIC incorporates a series of superconducting magnets, each uniquely constrained by stringent requirements for field quality, aperture, and spatial integration. Among these, B0pF is a forward spectrometer magnet closest to the...
The Electron-Ion Collider (EIC), hosted by Brookhaven National Laboratory, is designed to deliver a peak luminosity of 10^34 cm−2 s−1. The interaction region (IR) of the EIC imposes several constraints in terms of field quality, aperture, and spatial layout, which necessitates the development of several unique superconducting serpentine direct wind magnets. These magnets are constructed using...
The Optimum Integral Design (OID) with Direct Wind (DW) technology offers a unique value engineering opportunity for the Interaction Region (IR) dipole B1ApF of the Electron Ion Collider (EIC). The current design of the B1ApF magnet is based on the conventional cosine theta configuration using Rutherford cable. As compared to most accelerator magnets, B1ApF has a small coil length (1500 mm) to...
The Electron-Ion Collider (EIC) requires eight solenoid magnets to polarize the spin of the electron beam. These magnets, called SPIN ROTATORS, are categorized as four LONG (6.2 m) and four SHORT (2.5 m). They operate at a peak magnetic field of about 8.5 T with a 100 mm bore diameter. The integrated magnetic field along the axis is the figure of merit for these magnets, being respectively...
Brookhaven National Laboratory (BNL) was chosen to host the international Electron-Ion Collider (EIC), which will collide high energy and highly polarized hadron and electron beams with a center of mass energy up to 140 GeV. The IR will be loacted at RHIC's IR6; due to the requirements of the physics community the magnet designs are very challenging.
Space constrains in transverse and...
The Circle Electron Positron Collider(CEPC) is a large international scientific project initiated by and to be hosted in China. It will produce large samples of Higgs, W and Z bosons to allow precision measurements of their properties as well as searches for BSM physics.The magnet system uses a solenoid that is supported by an aluminum alloy cylinder and cooled indirectly by liquid helium to...
The STEP (Spherical Tokamak for Energy Production) program in UKAEA aims to develop a large-scale high-temperature superconducting (HTS) toroidal field (TF) model coil over four years, with plans to scale it up to a full-size TF coil. The TF model coil (TFMC), with approximate dimensions of 1m × 2m and a terminal current reaching up to 100kA, serves as part of the risk retirement program for...
A European Research, Development & Demonstration (RD&D) program is being proposed by EUROfusion and partners to address key challenges and demonstrate the feasibility of safely quench-protecting large-scale High-Temperature Superconducting (HTS) magnets. This initiative is designed to pave the way for the development and deployment of HTS magnets in large tokamaks. The program is divided in...
High-temperature superconductors (HTS) are increasingly being used to build
electromagnets to generate strong magnetic fields for a wide range of applications,
from medical devices and electric motors to future fusion reactors. These
superconductors are subject to quenching, a phenomenon that manifests itself as a
rapid rise in the temperature of the HTS material, leading to a loss of...
Optical fiber sensors are gaining attention as a promising technology for magnet monitoring and quench detection in fusion reactors. These sensors enable precise measurement of strain and temperature profiles within superconducting magnets and their integration into superconducting wires and cables has been demonstrated as viable. However, when embedded into fusion magnet systems, these...
The Quantum Materials Resonant Scattering Experimental Station (QMRSES) is a key component of the Hefei Advanced Light Facility (HALF) to investigate the quantum materials through the Resonant Elastic X-ray Scattering (REXS). The station assists researchers in investigating the electronic, spin, and orbital properties. The cryostat with the system is designed to provide various magnetic fields...
In order to reduce the beam emittance, four single sided anti-bending magnets(ABM) are employed in each standard arc of the storage ring at Wuhan Advanced Light Sourc(WALS). Each ABM is made of one half of a quadrupole and a pair of slim auxiliary poles, providing the transversal gradients and a dipole field simultaneously. Based on the NSGA2 Genetic Algorithm and chamfers at the ends of the...
State Power Investment Corporation (SPIC) is leading a project that uses cyclotron for proton irradiate power chips. Compared to electrostatic accelerator, cyclotron have the advantage of lower cost and higher beam intensity. However, a disadvantage of cyclotron is that the extracted beam has relatively large energy dispersion. For horizontally placed power chips, the beam must be injected...
An analytical magnet has been designed for the SV projiect at the Shanghai Advanced Research Institute, Chinese Academy of Sciences. According to the design parameters proposed by the Physics Department, we have confirmed the dimensions of the magnet and optimized the field quality. The simulation of the electronmagnetic field has been finished in OPERA 3D. In the paper, we give the...
The Research Racetrack Dipole Demonstrator (R2D2) is a short model magnet developed by CEA Paris-Saclay, in collaboration with CERN. The main goal is to demonstrate the feasibility of key technologies for future high field 16 T Nb3Sn magnets for particle colliders. Using a block-coil design, two different cable grades are wound in the same coil layer, in order to maximize the current density,...
As the principal components and conductors of the new generation of very high field superconducting magnets, High Temperature Superconducting Tapes (HTS tapes) are getting a particular attention on their selection, characterisation and uses.
In this context, Tokamak Energy has multiple specification covering the needed performance, tolerance and characteristics of HTS tapes. The most...
As the development of new superconducting materials gradually reaches the bottleneck, it is worth exploring new method to obtain superconducting tapes with better performance through the composite method. BSCCO and REBCO high-temperature superconducting (HTS) tapes are two main commercialized tapes at present. In this paper, based on the parallel physical structure of BSCCO/REBCO composite...
The second-generation high-temperature superconducting (HTS) materials (REBCO) have excellent characteristics such as high current density, high critical transition temperature, and high critical magnetic field, and have broad application potential in many fields such as power transmission, fusion applications and healthcare. However, in the actual use of REBCO tapes, it is inevitable to...
NHMFL is designing a 40 T superconducting user magnet [1]. In this magnet, significant quantity of REBCO coated conductor will be used for the insert coils. Fully characterizing critical current (Ic) of REBCO tapes at temperatures of its operation (4.2 K) and during a potential magnet quench (> 4.2 K) is critical to the success of the project. Due to the strong anisotropy of REBCO coated...
A 5 T high-temperature superconducting (HTS) magnet utilizing conduction cooling with REBCO tape has been designed and constructed at the Wuhan National High Magnetic Field Center (WHMFC). The magnet comprises three double pancake (DP) coils, employing a no-insulation (NI) winding technique，and is designed to operate at a current of 260 A at 4 K. During magnet operation, the turn-to-turn...
High-temperature superconducting tapes, such as REBCO, are anticipated to be used in ultra-high field magnets (40 T), fusion reactors, and particle accelerators. Significant progress has been made in enhancing the critical current of REBCO tapes by introducing pinning centers. At 4.2 K, the critical current of 4 mm wide tapes can reach thousands of amperes. However, accurately measuring the...
REBCO high-temperature superconductor has been widely used in high magnetic field applications, because of the excellent critical current properties and high critical temperature. However, REBCO tape has a huge width-to-thickness ratio (typically in the range of 1000-10000) to cause too high power dissipation in the applications. One of the effective ways to reduce AC loss is to divide the...
The development of new high-field superconducting magnets is significantly constrained by the limiting critical properties of superconducting coated conductors (CCs). A major challenge is that REBCO tapes have high critical current densities. It is essential to create micro-bridges on REBCO tapes to test the critical current at low temperatures and high fields. However, pulsed high magnetic...
Steel-hull ships generate a magnetic field making them vulnerable to weapons equipped with magnetic sensors. To mitigate this threat, navies use ship deperming treatments to reduce the ship’s magnetization. We design a flat seabed coil with a racetrack shape to deperm a ship that remains stationary above the coil for quick operation. The required magnetic field generated by the coil is...
Zero-flux DC current transformers (DCCTs) utilize a closed-loop flux detection control to generate a compensation current that cancels the magnetic flux in the magnetic core induced by the measured current. The effectiveness of cryo-DCCTs, composed of copper flux detection coils and a superconducting compensation coil, for measuring superconducting cables that carry tens of kA of current had...
Large aluminum alloy rings are vital components in wind turbine and high-speed train, serving as bearing rings, transition rings, and reinforcing structures. The structural stability and mechanical properties of these rings are critical to ensuring assembly precision and safety performance of these systems. However, the manufacturing process of large aluminum alloys rings inevitably introduce...
For long-distance acceleration applications such as electromagnetic catapults and high-speed maglev trains, usually, multiple short linear motors are joined together into longer linear motors as needed. In this paper, a new type high temperature superconducting-linear motor (HTS-LM) for long-distance acceleration applications is designed. The stator winding of the HTS-LM is a ring winding...
The various wireless power charging (WPC) units for high speed hyperloop train should be practically required to supply electric power without overhead wire power lines of pantographs, since such a unit can reduce the construction cost for pantographs in the transportations. Generally, in order to charge superconducting levitation magnet for hyperloop train combined by WPC unit, the high power...
The International Maritime Organization has set a 'Net Zero' target for the maritime industry to reduce greenhouse gas emissions to zero by 2050 in response to climate change. To achieve this goal, the shipbuilding industry is focusing on the design and research of cryogenic equipment for the transportation of liquid hydrogen and carbon capture in cryogenic states. Liquid hydrogen must be...
The so-called fully superconducting magnetic bearing (SMB) is composed of a rotor of high temperature superconducting (HTS) bulk of YBaCuO and a stator wind wounded by HTS coated conductor tapes. The fully SMB has been developed a prototype and is in operation in Japan. The dynamics of fully SMB under long term operation is crucial to engineering applications, however, the experimental and...
This research investigates the feasibility of high-temperature superconductor (HTS) magnets as pivotal components for superconducting magnetic energy storage (SMES) applications, with a focus on their integration into power grids. SMES systems store energy in the magnetic field of superconducting coils, and the large current-carrying capability of HTS has shown its potential for SMES...
For the Electron Ion Collider (EIC) at BNL, the interaction region (IR) magnet closest to the EIC experiment on the forward (outgoing hadron and incoming electron) side, denoted B0PF-Q0EF, must satisfy many conflicting machine detector interface (MDI) requirements. First it must provide sufficient transverse field in a large warm bore to provide spectrometer functionality for outgoing...
REBCO conductors with high critical currents and high engineering current densities (Je) in magnetic fields of 20 T and above are needed for several applications such as particle accelerators and fusion reactors. We have demonstrated round, 2.5 mm diameter REBCO STAR® wires with a Je of about 600 A/mm^2 at 4.2 K, 30 T at a bend radius of just 15 mm, using high critical current REBCO tapes....
A new quench protection technique, Energy Shift with Coupling (ESC), has recently been proposed, which is very promising for the protection of high-field magnets. The ESC system includes normal-conducting coils that are highly magnetically coupled to, but galvanically insulated from, the magnet coils. When the system is activated, rapid shift of energy from the magnet to the ESC coils is...
Brookhaven National Laboratory (BNL) was chosen to host the international Electron-Ion Collider (EIC), which will collide high energy and highly polarized hadron and electron beams with a center of mass energy up to 140 GeV. The Interaction Region (IR) requires several large aperture, relatively high field superconducting dipole and quadrupole magnets, some of which are very closely spaced....
ReBCO tapes and cables are of great interest high field magnets because of their high current carrying capability, high Tc, and high magnetic field tolerance. The magnetization and AC loss properties of ReBCO tapes are well known, however, for cables, especially the helically wound counterparts some interesting aspects remain. It is well known that for ReBCO tape the losses are strongly...
Conductors and magnets for fusion applications based on High Temperature Superconducting (HTS) materials are currently being designed and tested. Quench propagation in such conductors is an open issue due to the small normal zone propagation velocity when compared to Low Temperature Superconductors. This, in turn, makes the quench detection and the protection of HTS magnets more challenging....
Brookhaven National Laboratory (BNL) was chosen to host the international Electron-Ion Collider (EIC), which will collide high energy and highly polarized hadron and electron beams with a center of mass energy up to 140 GeV. The Interaction Region (IR) requires several large aperture, relatively high field superconducting dipole and quadrupole magnets, some of which are very closely spaced....
High-Temperature Superconductors (HTS), particularly Rare-earth Barium Copper Oxide (ReBCO) tapes, offer the most promising path towards developing high-field magnets for fusion machines, meeting stringent requirements for high operating currents, current densities, and compact coil geometries. The high tolerance of ReBCO to the tensile strength and compressive strain lead to the development...
Proper detection and localization of quench events is essential to protect superconducting magnets for particle accelerators. Voltage taps are widely adopted for low-temperature superconductors (LTS), but they do not ensure reliable quench detection for high temperature superconducting (HTS) magnets. Indeed, the propagation velocity of the normal conducting zone is in the order of m s−1 for...
Brookhaven National Laboratory (BNL) has a unique Direct Wind (DW) technology which is used
to fabricate complex multi-functional superconducting magnets. Some of these magnets have been
integrated in currently operational accelerator complexes, such as, HERA, BEPC, JPARC, and
RHIC. These multi-layer magnets do not require custom production tooling necessary for cabled
magnets. The...
A Spiral Copper-plated Striated Coated-conductor (SCSC) cable is a round cable composed of striated REBCO coated-conductors (CCs) wrapped around a metal core wire. A REBCO film in each CC is divided into multifilaments by laser-striation, while Cu-plating surrounds the whole cross-section. Thanks to this structure, SCSC cables are promising for application to accelerator magnets since the...
A quench detection and fast discharge scheme has been deployed in the Superconducting Magnet Test Facility at MIT's Plasma Science and Fusion Center for use with high-temperature superconductor (HTS) devices. In particular, the system was developed to protect the SPARC Central Solenoid Model Coil (CSMC), an insulated HTS cable magnet constructed of 40 turns of PIT VIPER cable, as well as the...
PSALM (Patterned Superconductors for AC Loss Minimisation) is a latest developed concept of high-current and low-loss HTS cables for high-power AC applications. In this work, samples of PSALMs with single superconducting layer are manufactured, tested, modelled, and analysed. In the experiments, the critical current degradation and the transport AC losses are measured. In the simulation, with...
The design and simulation of a modified Rayleigh Line Pulse Forming Network (PFN) is presented for active quench protection of superconducting magnets. In this context, the PFN is a network of capacitors and inductors designed to deliver energy to quench heaters over a significantly longer period than a single capacitor or capacitor bank. The PFN is advantageous for protection of coils...
Bi-2212 conductors and accelerator magnets have been advanced in the USA through a collaboration between US national labs, university, and wire industry connected by the US Magnet Development Program (MDP) and by recently the U.S. Department of Energy’s Accelerator R&D and Production (ARDAP) Office. For example, a high engineering critical current density of 1000 A/mm2 has been demonstrated at...
For offshore superconducting wind generators, the complex operating conditions inside the machine—including thermal losses, stress, vibration, and transient load variations—pose significant challenges to the stable operation of the magnet. These factors can trigger coil quenching, potentially leading to the burnout of excitation coils and further generator fault condition. This study is a...
SupraFusion is a French research program aiming to boost HTS (High-Temperature Superconductors) technologies towards large-scale societal applications and particularly compact fusion machines. In the framework of this program, a large-scale HTS magnet demonstrator is presently under design. This large-scale magnet aims to demonstrate our capability to reach safely a peak field of about 20 T...
The SSRF (Shanghai Synchrotron Radiation Facility) superconducting wiggler consists of three parts: a superconducting multipole magnet, a cryostat system and magnet power & control system. Superconducting multipole magnets can generate a strong magnetic field with a peak of 4.2T, and the generated magnetic field alternates positively and negatively along the direction of electron motion in the...
No-insulation (NI) rare-earth barium copper oxide (REBCO) magnets have demonstrated the potential to achieve high magnetic fields in compact spaces. Several REBCO magnets, whether combined with resistive outserts or operating standalone, have successfully reached fields over 20 T. However, many quench events have been reported during operation without clearly identified causes, leading to...
High temperature superconducting (HTS) magnet is only option for applications of high magnetic field above 20 T due to high upper critical magnetic field at low temperature. However, the quench detection is challenge for HTS magnet since its low quench propagation velocity coming from low thermal conductivity and wide operation range of temperature. In this paper, we propose a novel quench...
Tokamak controlled nuclear fusion emerges as a promising solution to the current global energy predicament. The solenoid coil, a pivotal component, plays a crucial role in confining plasma within the Tokamak device. Bi-2223/Ag high temperature superconducting tapes, with a high critical temperature and excellent machinability, are favored material for fabricating solenoid coils. Nevertheless,...
The Bi-2223/Ag high-temperature superconductor (HTS) tape has become one of the best candidate materials for high-performance superconducting magnets due to its high current-carrying capacity and excellent multi-filament stability. To achieve the capability of transporting thousands of amperes or even higher current levels, it is common to assemble multiple sub-cables constructed from...
High-temperature superconductors (HTS) are being implemented in magnets and coils for fusion energy, aviation, wind generators, high-energy physics, and nuclear magnetic resonance. HTS coils face a critical challenge for use in these applications: their inherently slow quench propagation velocity complicates quench detection and protection, raising concerns about operational safety and...
High-temperature superconductors (HTS), with their appreciable current density and superior thermal stability, exhibit significant potential for high-field applications. Compared to the normal zone propagation velocity (NZPV) of low-temperature superconductors (LTS), the NZPV in HTS is typically two to three orders of magnitude slower than that in LTS. The slow quench propagation...
The Electron-Ion Collider (EIC), a new facility to be built in the United States at the U.S. Department of Energy’s Brookhaven National Laboratory in collaboration with Thomas Jefferson National Accelerator Facility. The EIC project will provide us answers to the mysteries of the origin of mass and building blocks of our universe.
There are many different types of superconducting magnets near...
Quench detection is critical to protect superconducting coils, especially in fusion superconducting magnets, due to enormous energy. A quench event can result in significant damage to fusion superconducting magnets. A High Voltage Signal Conditioner (HVSC) designed for quench voltage detection in the ITER superconducting magnet system has been developed collaboratively by the Korea Institute...
Suprafusion is a French exploratory program focusing on the development of high-temperature superconductors (HTS) to meet tomorrow's energy and societal challenges, using fusion needs as a vector for this research. In particular, the program aims to design, manufacture and test a large-scale HTS demonstrator magnet. To meet this goal, the program will follow a stepwise development plan with...
Stacked tape superconducting cables based on second-generation high-temperature superconducting REBCO tapes exhibit high current density and excellent mechanical performance under cryogenic conditions, showing significant potential for applications in power transmission systems of space solar power station. This study investigates the quench behavior of HTS REBCO stacked tape cables under...
No-Insulation (NI) or NI-like techniques (including metal insulation) have become essential for quench protection in high-temperature superconducting (HTS) coils. However, the turn-to-turn resistance inherent to NI techniques is an intrinsic property that cannot be fully controlled by coil designers, leading to several challenges. One critical issue is asymmetric quench behavior, where the...
Commonwealth Fusion Systems (CFS) is developing and building a commercially relevant fusion energy machine that will produce more energy than is put into it. In this research, a reusable structural case for testing toroidal field (TF) magnets in the Coil Test Stand Cryostat prior to integration in the SPARC Tokamak has been developed and is currently employed in this critical evaluation of TF...
The magnets of the SPARC tokamak as developed by Commonwealth Fusion Systems and the Massachusetts Institute of Technology include superconducting magnet termination cables that supply power to the winding pack. It is important to qualify these superconducting cables because they are epoxied into the cable magnets, making their removal extremely difficult, possibly scrapping a magnet. We...
Thea Energy, Inc has designed, developed, and tested the “Canis” 3x3 array of high-temperature superconductor (HTS) planar coils, which will serve as a prototype for the development of the “Eos” planar coil stellarator. The Canis 3x3 magnet array support systems consist of a vacuum vessel, a radiation shield, first and second stage cooling systems, a magnet current distribution system, and a...
Magnets remain the cornerstone technology in the development of high field fusion machines such as tokamaks. In this context, high-temperature superconductors (HTS) and the conductors derived from them are considered enabling technologies . HTS materials enable higher magnetic fields, paving the way for more compact and potentially higher-performance machines. However, the integration of these...
The superconducting (SC) magnets of the Divertor Tokamak Test (DTT) facility, a fusion experiment under construction at the ENEA Research Center in Frascati, Italy, require several tens of kA, necessitating the use of SC feeders. These feeders are based on the Cable-in-Conduit Conductor (CICC) concept, where a bundle of twisted NbTi strands is encased in a stainless-steel jacket and cooled by...
Superconducting (SC) magnets are becoming the base for magnetic-confinement fusion devices. However, the energy demands of their power supply (PS) systems pose a critical challenge to their economic viability, especially in the perspective of delivering a net energy to the electrical grid. Conventional power systems introduce significant losses, from resistive busbars to current leads, which...
The high-temperature superconducting current lead (HTSCL) plays a key role in supplying large currents to the ITER superconducting magnets. To measure the temperature of the HTSCL cooled by helium gas, PT-100 sensors are installed at both the warm end of the HTS section and the room-temperature terminal. These sensors are exposed to a high-voltage environment, depending on the type of ITER...
Bridge-type mechanical lap joint with indium insertion between REBCO tapes is planned to be utilized for joint-winding of high-temperature superconducting (HTS) helical coils in heliotron-type fusion reactors, such as FFHR-d1 [1]. Shear strength evaluation of single lap joints using tensile shear testing at 77 K, self-field has been conducted to discuss if the joints can keep their performance...
The Central Solenoid (CS) coaxial joint is an electrical connection designed to link the terminals of the CS module to their busbar extensions. This paper outlines the manufacture and testing of the CS coaxial joint Production Proof Samples (PPS), during the CS module stacking process. Once the PPS was completed, it was sent by the ITER Organization (IO) to the CEA. Detailed and increasingly...
Feeders, as key components located on the upper and bottom of ITER tokomak, provide power supply, cooling and signal measurement to ITER superconductive magnets (PF, TF and CC coils). The installation of Feeder joints consists of three major stages (joint assembly, joint insulation, mechanical installation) and hundreds of precise operations, and involves thorough planning, engineering,...
The ITER Feeder joints, as critical connections between the Feeders and the superconducting magnet system, play a vital role in ensuring the system's safety and stability. The on-site joint insulation process is a core task to meet design objectives and ensure operational reliability. Since the Feeder joint insulation work began in September 2022, significant progress has been made despite the...
In the design of DC busbar flexible connection in Power Supply System of CRAFT (Comprehensive Research Facility for Fusion Technology，China), water-cooled aluminum busbars interconnections are connected through aluminum flexible connectors to compensate for thermal expansion and Installation deviation. As the contact surface between the DC busbar and the flexible connection is very small, the...
High-quality joints are essential for building practical assemblies of fusion-scale magnets, integrating the magnets with bus and leads, and allowing modularity in magnet design. The essential figure of merit for the quality of the joint is its electrical resistance which should be as low as possible. Due to its low bulk resistivity and high ductility, indium is often used to cold-weld the...
We have been working on several projects to develop 32 T to 40 T class all superconducting magnet for end-users. For the first step, four REBCO tapes were estimated: 1) THEVA (TV); 2) Shanghai Superconductor Technology (SST); 3) Faraday Factory Japan (FFJ); and 4) Fujikura (FJK). From this estimation, we found that, except TV’s tape, the coils of all REBCO tapes were suddenly deformed at...
20 Tesla is the nominal field limit for practical low temperature superconducting (LTS) magnet operating at 4.2 Kelvin. To achieve field above 20 Tesla, methods such as LTS magnet operating at sub-atmospheric pressure or LTS/HTS hybrid magnets, are normally adopted. Magnets working at sub-atmospheric pressure have high cryogen operating cost and high ice-blockage risk due to air leakage into...
Chinese High Magnetic Field Laboratory (CHMFL) is one of the five major labs of steady high magnetic field around the world. In Sep. 2024, its new built resistive magnet produced a steady field of 42.02 Tesla(T) with the power supply of 32.3 MW, which was the highest magnetic field of the resistive magnet in the world. In order to meet the operation requirements of the new magnet that the...
The High Field Magnet Laboratory of the Radboud University in Nijmegen has been building a 45 T hybrid magnet system over the last 10 years. The 12.3 T Nb3Sn CICC outsert coil has been wound and further processed by the National High Magnetic Field Laboratory in Tallahassee FL, USA. The coil is placed in a separate enclosure and will be operated at 4.5 K in an atmosphere of 1 bar of helium...
The generation of ultra-high magnetic fields is critical for advancing a wide range of scientific and technological research areas, including condensed matter physics, materials science, and biomedical imaging. Conventionally, achieving magnetic fields exceeding 40 T requires the combined use of superconducting and resistive magnet technologies, which are characterized by their substantial...
All-superconducting high-field magnets are in high demand across various scientific disciplines, including large-scale science devices, materials science, and biology. They play a crucial role in researching material properties, the origin of life, and disease prevention and treatment. These magnets offer significant advantages, such as compact size, low power consumption, flexibility, and...
This work presents a graded parallel-wound (GPW) coil technique for high temperature superconductor (HTS) magnet consisting of multiple pancake coils. The coil is wound by parallel-stacked HTS tapes, all the coils are connected in series, so that they have a same transport current. The key idea is to assign number of parallel-stacked tapes to pancake coils on different position of the magnet:...
The 33T Cryogen-Free Superconducting Magnet (33T-CSM) project is progressing at Tohoku University Institute for Materials Research. The 33T-CSM consists of a 19T REBCO coil (HTS) with a 68mm bore and a 14T Nb3Sn+NbTi Rutherford coil (LTS) with a 320mm bore. The 14T-LTS coil was completed in 2024 and its stand-alone test was successfully performed. The 19T-HTS coil design, which involves...
A 25 T cryogen-free superconducting magnet (25T-CSM) has been installed at the High Field Laboratory for Superconducting Materials, Institute for Materials Research, Tohoku University. It consists of low-temperature superconducting (LTS) outsert coils and a high-temperature superconducting (HTS) insert coil. The LTS coils are composed of three Nb3Sn sections (L1–L3) and three NbTi...
In the past few years, there is a growing interest in low-inductance high-field solenoid magnets for high-energy physics experiments including future muon colliders. Advanced Conductor Technologies (ACT) has recently developed CORC$^{®}$ wires wound from REBCO coated conductors with improved bending flexibility that allow for bending to a 20 mm radius and CORC$^{®}$ cables containing up to 96...
Iron-based superconductor, owing to their exceptionally high upper critical fields and relatively simple fabrication processes, exhibit significant application potential for high-field superconducting magnets. This research designed a 5 T iron-based superconducting high-field insert coil operating in the 28 T background magnetic field. An optimization strategy was applied to refine the...
The central magnetic field of current all-superconducting hybrid magnets used in engineering applications is limited to below 40 T, primarily due to challenges such as screening-current-induced stress (SCIS)and high background magnetic field. SCIS significantly impacts the electromechanical performance of insert high-temperature superconducting (HTS) coils, particularly under high background...
High-temperature superconductors (HTS) are indispensable for producing magnetic fields exceeding 20 T, a subject that has attracted substantial research efforts in recent years. This study aims to develop a conduction-cooled all-HTS magnet capable of generating a 20 T magnetic field with a 50 mm room temperature bore. The magnet has been designed to operate at a maximum temperature of 20 K...
Electromagnetic forming (EMF), renowned for its high forming speed and strain rate advantages, has been extensively applied in industrial manufacturing, transportation, and other sectors. The principle of EMF involves generating an electromagnetic force on the workpiece using a pulsed magnet, driving the material to undergo plastic deformation. However, traditional solenoid-based forming...
The structure of the pulsed vector magnet has been optimally designed at the wuhan national high magnetic field center (WHMFC). The pulse vector magnet consists of a magnet that generates a magnetic field in the z-direction and a magnet that generates a magnetic field in the x-direction. the z-direction magnet is in the center hole of the x-direction magnet. The two magnets are held together...
Solenoidal high-field pulsed magnets typically employ layered reinforcement techniques to mitigate the substantial Lorentz forces acting on the conductors. The thickness of each reinforcement layer must be optimized through stress analysis to achieve a uniform and reasonable stress distribution. Although commercial finite element analysis (FEA) software can accurately calculate the stresses...
To improve visualization capability, simulation effort, and experiment efficiency for the Pulsed High Magnetic Field Facility (PHMFF) at Wuhan National High Magnetic Field Center (WHMFC), an intelligent operation and maintenance method based on digital twin technology is proposed. Reference to standard model, digital twin framework is first described including physical entity, virtual entity,...
The authors have designed a 1-MJ-class mobile superconducting magnetic energy storage (SMES) system. The SMES coil features a force-balanced helical coil (FBC) to reduce weight, as the FBC minimizes the mass required to support the induced electromagnetic forces.
In this study, the authors propose using 0.67-mm diameter MgB2 strands, manufactured by Hitachi, Ltd., for winding the FBC....
With the goal of generating net energy by 2040, fusion energy represents a cornerstone in the development of sustainable power generation technology, combining innovative approaches with advanced engineering solutions. Several programs aim to demonstrate the viability of fusion as a scalable energy source. However, the integration of remountable joints, the presence of large amounts of stored...
Superconducting wires undergo large plastic deformation during manufacturing of Rutherford cables, especially at the cable edges. Previous studies on Restack Rod Process (RRP) Nb$_3$Sn wires have shown that the position of the strands in the cable and the orientation of the subelement stack, with respect to the main rolling direction during cabling, are affecting the amount of plastic...
With the innovation of accelerator magnet technology, the design of superconducting magnets is also changing and put forward high requirements on the performance of NbTi superconducting wire, which requires high critical current density and ultra low loss. A new type of superconducting wire with high critical current density, fine filament, ultra low loss NbTi/Cu5Ni/Cu has been developed in...
The superconducting strands, essential components for the future energy industry and fundamental scientific research, demand higher specifications to fulfill the requirements of increased energy production and advanced research. The manufacturer of superconducting strands has been performing continuous research to satisfy these requirements. However, upcoming facilities slated for construction...
Nb3Sn wires are wildly used in high-field (> 10 T) magnets and have great potential value in the next several decades. Internal-tin Nb3Sn strand has been developed by many methods for the future fusion reactor, high energy accelerator and so on. Increasing the critical current density of Nb3Sn wire, reducing the use amount of wire in magnets and reducing the price are important ways to promote...
In the development of high-Jc superconducting wires, the formation of Nb3Sn is critical, and KAT utilizes Nb filaments combined with SnTi alloy to facilitate Nb3Sn formation. In this study, a ternary alloy was fabricated by incorporating 5 wt% Cu into SnTi alloy via powder metallurgy, resulting in micro-sized SnCuTi alloy particles. These particles were then incorporated into high-Jc wires,...
Scientists have incorporated other metal as pinning centers into Niobium-titanium alloys in order to increase the critical current density of Niobium-titanium superconductors. This type of superconductor is known as an artificial pinning center niobium-titanium superconductor. Methods for fabricating artificially pinned superconductors include Rod-based, Gun-drill, Diffused-layer, Jelly-roll,...
Offshore wind energy offers substantial potential to drive the decarbonization of the energy sector through the generation of large amounts of renewable power. Recent trends in the offshore wind industry favor increasing turbine size and rated power to reduce the levelized cost of energy (LCOE). However, scaling up brings challenges in terms of structural integrity, thermal management,...
Superconducting (SC) coils used in rotating machinery necessitate effective electromagnetic shielding to mitigate AC losses caused by asynchronous field harmonics created by the armature windings. Coils employing low-temperature superconductors, such as niobium-titanium, are characterized by a narrow thermal margin and limited cooling capacity within the cold mass. Conventional "rule of thumb"...
Flywheel generators are used as power sources for various plasma experiments because of their long-life span and high-power repetition. However, huge capacity inverters for energy conversion have been necessary to charge and discharge rotating energy. Furthermore, in conventional flywheel generators, the power output also decreases as the rotation speed decreases. In response to this, the...
Aviation electric propulsion is characterized by distributed propulsion, flexible maneuverability, and high efficiency with low pollution. The aviation superconducting electric propulsion system based on the concept of direct-drive power generation from turbines, which is one of the most promising solutions for meeting the power demands of high-power aviation electric propulsion aircraft. This...
The development of high-temperature superconducting (HTS) electrical machines results in applications of various fields, as they have higher efficiency and power density. Axial field machine (AFM) is a machine topology with higher efficiency and power density, and is a novel way to achieve fully-superconducting electrical machine for various applications. Stacked HTS coated-conductors (CC)...
High-Temperature Superconducting (HTS) Coated Conductors (CCs) can be sliced and stacked together and utilised as Trapped Field Stacks (TFSs) for electric motors and generators after magnetisation. However, TFSs are vulnerable to higher-order harmonic waves within the air gap of electric machines, which stem from the stator's alternating arrangement of slots and teeth, leading to a phenomenon...
To meet the requirements of the high power-to-weight ratio and high efficiency for future electric aircraft, high temperature superconducting (HTS) electrical machines are expected to be the effective solutions. However, the HTS armature windings produce AC loss when operating in HTS electrical machines, leading to a reduction in the efficiency of the HTS electrical machines. This paper will...
Growing environmental concerns have increased the demand for high-power-density electric propulsion systems. One way to achieve higher power density is through the use of superconducting technology. In particular, no-insulation (NI) high-temperature superconducting (HTS) coils offer improved power density due to their ability to carry high currents and withstand external...
The torque tube is crucial for the normal operation of high-temperature superconducting motors, serving as a mechanical support and torque transmission element. Including adiabatic performance, cold shrinkage performance and mechanical stress, the performances of torque tube are important indicators in superconducting electrical design, which need to be analyzed and studied comprehensively....
In order to meet the requirement for rapid switching between left- and right-handed circularly polarized light, we have designed and constructed an undulator incorporating a combination of permanent magnets and electromagnets. The 0.5-meter-long prototype undulator generates a horizontal magnetic field through four rows of permanent magnets, each with adjustable horizontal gaps, while the...
The Shanghai Synchrotron Radiation Facility (SSRF) insertion device team is developing several 4.2-meter-long elliptically polarized undulators (EPU) for the Hefei Advanced Light Facility (HALF). Magnet keepers are directly installed onto the sliding girders, rather than utilizing traditional pre-assembled subassemblies, to ensure precise positioning of the magnets in the beam direction. We...
This paper presents the development of a cryogen-free 2G High-Temperature Superconducting (HTS) wiggler for use at the National Synchrotron Radiation Research Center (NSRRC). The proposed design leverages the advanced properties of 2G-HTS materials to provide magnetic fields around 2.7 T. The wiggler utilizes modified double pancake winding techniques for the HTS coils. This method doesn't...
Precise magnetic field measurement of undulators is a cornerstone in optimizing synchrotron radiation facilities. This study introduces a position-sensitive Detector (PSD)-based system aimed at enhancing the accuracy of point measurements using Hall probes. By focusing on the challenges of positional deviation and misalignment, the system improves the precision of magnetic field data critical...
Compared to the conventional temperature oscillator, CPMU enhances the peak magnetic field of the oscillator. However, due to limitations in its design structure, a visual high-precision magnetic measurement based on C# is developed for vacuum-based magnetic field testing and correction. The measurement system comprises a Hall probe, a vacuum translation motor, a laser interferometer optical...
The bulk high-temperature superconducting (HTS) undulator constructed from RE-Ba-Cu-O (REBCO) bulks demonstrates the capability to generate an undulator field up to 2.1 T of 10 mm period [1]. This performance exceeds that of the current state-of-the-art permanent magnet and low-temperature superconducting undulators [2]. Compared to REBCO bulks, the alternative MgB2 bulk superconductors...
High-field magnet designs for fusion increasingly utilize stacked high-temperature superconducting (HTS) tapes embedded in a solder matrix through vacuum impregnation. The extreme mechanical loads placed upon the tapes as well as multiple sources of heating within a fusion machine make voids within the solder matrix represent a critical source of uncertainty. If not properly accounted for...
Next-step US spherical tokamak test facilities and/or compact stellarators configured as fusion pilot plants (FPP) to support fusion commercialization are recommended options by multiple recent consensus studies. The goal for a FPP is to make 50-100 MW net electricity power plants with either extended long pulses or steady state options. Significant HTS conductor and coil technology efforts...
High-temperature superconducting (HTS) magnets are emerging as key R&D components for compact and economical future fusion devices. Institute for Plasma Research (IPR), India, has undertaken an R&D initiative focused on the design and development of fusion-relevant HTS magnets. This initiative covers the development of compact solenoids and D-shaped magnets and dedicated test facilities. As a...
Demo4 is a unique, high-field device comprised of a total forty-four high-temperature superconducting (HTS) coils made from stacked rare-earth barium copper oxide (REBCO) tapes in a compact, spherical tokamak (ST) configuration. The complete magnet set consists of twenty-eight toroidal field (TF) coils manufactured into fourteen TF limbs, and sixteen poloidal field (PF) coils in two PF stacks....
The SPARC tokamak developed by Commonwealth Fusion Systems (CFS) and the Massachusetts Institute of Technology Plasma Science and Fusion Center (MIT PSCFC) uses pulsed high temperature superconductor (HTS) magnets with composite insulation. Each of the SPARC insulated magnets is to be acceptance tested to 21 kV in Paschen minimum conditions, and any failures are to be repaired before...
General Atomics (GA) is fabricating seven ITER Central Solenoid Modules (CSM) for the ITER Organization (IO). As part of the fabrication process, all CSMs undergo factory acceptance testing (FAT) prior to shipment to the IO. The FAT includes Paschen testing the CSMs up to 15kV between 1e-3 and 100 mbar. During post-cooldown Paschen testing of CSM6, there was a fault on one of the terminal...
JT-60SA is the world’s biggest operating tokamak (R=3, a=1.2) having achieved a plasma volume of 160m$^3$ in 2023. As the first of a new generation of large fusion experimental machines, its commissioning represents a unique opportunity to gain invaluable operational experience.
The magnets form the backbone of any tokamak, and the superconducting magnet systems of JT-60SA play a critical...
The GFG Fusion Power Plant is based on a stellarator with a four period quasi isodynamic plasma which, supported by results from Wendelstein 7X and advances in plasma modelling and stellarator optimisation, is expected to achieve the required confinement levels. It is sized to provide output electrical power comparable to a conventional large power plant, with realistic assumptions about power...
The superconducting solenoid for the muon source to be installed in the future second target station of materials and life science experimental facility of J-PARC is required to be highly radiation resistant. Over a 10-year operation period, the superconducting solenoid is expected to reach an absorbed dose of 100 MGy and a neutron fluence of 7.8$\times10^{22}$ $n/m^{2}$. A research and...
The US Magnet Development Program is considering REBCO symmetric tape round (STAR®) wires as candidates for the next generation of high-field hybrid magnets for high-energy particle colliders. In high-field dipole magnets, the conductors experience strong mechanical loads transverse to their longitudinal axis. The current-carrying capability of the superconductor may decrease under these...
ITER Central Solenoid (CS) at the heart of tokamak progresses its assembly on a platform in the ITER Assembly Hall where the six coil modules are vertically stacked and connected individually to their corresponding bus bar leads, and finally to be installed with all structural components that apply a vertical pre-compression on the completed stack. The status of manufacturing and assembly of...
Thea Energy, Inc. is currently developing the “Eos” planar coil stellarator, the Company’s first integrated fusion system capable of forming optimized stellarator magnetic fields without complex and costly modular coils. To demonstrate the field shaping capability required to enable a planar coil stellarator, Thea Energy designed, prototyped, and tested the "Canis" 3x3 array of...
This study investigates the impact of nickel-plated YBCO (Yttrium Barium Copper Oxide) tapes on current sharing levels and performance, as compared to traditional copper-wrapped tapes. Prior simulations demonstrated a correlation between defect density and current sharing levels, prompting an experimental evaluation. Nickel-plated tapes were utilized to enhance thermal conductivity by...
High-Temperature Superconducting (HTS) fusion magnets play a pivotal role in plasma confinement for tokamaks and stellarators. Building on insights from the LDX and RT-1 programs, Openstar Technologies has developed a novel approach utilizing ReBCO for a levitated dipole magnet, powered by HTS flux pumps. We aimed to demonstrate a 5.6 T DC magnet made of 14 solder impregnated HTS coils,...
Understanding the dependence of the critical current, I$_c$, on magnetic field intensity and orientation, as well as on temperature is essential for developing reliable models for REBCO tape-based magnet design. This knowledge is particularly critical for advancing ultra-high-field magnets (20–40 T) required for applications ranging from fusion and particle accelerators to high-field science....
The ITER Pre-Compression Ring system provides radial constraint and centripetal load to the 18 TF coils. The rings are composed of six pultruded fiberglass-reinforced composite rings with an external diameter of 5.6 m, a cross-sectional area of 95,600 mm², and a weight of 3.4 tons each. These rings are designed to operate at 4.2 K during 20 years under preload given at room temperature during...
A candidate of fusion reactor using magnetic confinement is the stellarator, which has an inherently steady-state nature. Among the various stellarator types, the optimized stellarator represents a promising topology. One challenge is the complex coil shapes required to create the necessary magnetic field to confine the plasma. As the achievable fusion power increases with the strength of the...
This is a comparative study of the angular critical current ($I_c$) in different REBCO coated conductors (CC) at high magnetic fields ($B < 45$ T) performed with torque magnetometry (US Patent 12,187,540)
The high $I_c$ of REBCO makes transport measurements challenging at low temperatures ($T$) and high $B$, which are crucial for magnet construction and pinning mechanism studies. On the...
The ITER Central Solenoid (CS) is under fabrication by the US ITER organization and its subcontractors. US ITER will supply seven modules to ITER IO, six of which will be assembled in a stack that forms the ITER Central Solenoid. All CS modules (CSM) were or will be tested at 40 kA in the Final Test facility at General Atomics.
CSM 3 testing campaign took place in 2021, and a breakdown...
Stellarators have traditionally been constructed using complex 3D magnets to produce the helical-shaped magnetic field configuration needed to confine the plasma. The complexity of manufacturing stellarator magnets has prevented their large-scale development, despite their advantageous steady-state operations and current-free plasmas compared to other magnetic confinement devices such as...
We have manufactured the 1/2-scale demonstration no-insulation (NI) REBCO magnet system for ‘skeleton cyclotron’ with no iron core (air-core), called “Ultra Baby Skeleton Cyclotron (UBSC).” The USBC magnet consists of center coils, main coils and AVF coils generating the azimuthal varying field. The outermost size of magnet is approximately 70 cm, and the designed center magnetic field is 1.6...
A detailed overview of the ultimate magnet design developed within Work Package 8 of the collaborative European project HITRIplus is presented. Focused on the development of superconducting magnets for ion therapy synchrotron and gantry systems, the study introduces an innovative approach utilizing a curved Canted Cosine Theta layout magnet based on NbTi superconductor. The design targets a...
We present results from testing a high-temperature superconducting (HTS) magnet prototype for proton therapy. This magnet is specifically designed for a novel rotating gantry capable of delivering the entire proton beam energy range (70–225 MeV) while maintaining a fixed magnetic field in the superconducting magnets. The gantry's innovative layout simplifies the magnet design by enabling the...
In particle therapy, multiple treatment angles are generally used to concentrate the absorbed dose in a tumor and to minimize the dose in healthy tissues in the vicinity of the tumor. This is typically achieved with a rotating gantry system. However, implementing a rotating gantry system presents serious challenges due to high cost and enlargement of a space for a large-scale...
Various types of magnets, including dipole, quadrupole, sextupole and combined-function type, are used for beam transportation and delivery in proton therapy systems (PTS). Toward urgent demands for lightweight PTS, we will discuss the opportunities and challenges on magnet design issues, especially for gantry beamline. Two gantry beamline design schemes will be introduced and compared: (1) a...
Subtle variations in cell density often serve as precursors to shifts in physiological characteristics. Consequently, the accurate detection and detailed characterization of cell density are of paramount importance for elucidating cellular functional states, pharmacological responses, and cellular heterogeneity. Contemporary mainstream methods for density-based characterization predominantly...
Microrobots are increasingly being applied in bionics and medicine, demonstrating significant potential in minimally invasive surgery and targeted drug delivery. Among them, magnetic microrobots have attracted considerable attention, driven by the interaction between external magnetic fields and built-in permanent magnets. This enables the separation of the driving system from the robot body,...
The magnetic field distribution of externally driven permanent magnets and its effects on the magnetic force and torque at the tip of a Magnetic Guidewire (MG) directly determine the precision of its deflection and movement. To enhance the control accuracy of MGs within blood vessels, this study proposes an MG magnetic driving model based on a nonlinear magnetic field. The research begins by...
For a single permanent magnet to control the orientation of the magnetically controlled capsule endoscope (MCCE), it is difficult to meet the demand for a complex orientation adjustment in three-dimensional space due to the non-uniformity of the magnetic field and insufficient torque. A cooperative control strategy of dual permanent magnets based on a rotating magnetic field is proposed to...
As a non-invasive and painless treatment method for neurological diseases, transcranial magnetic stimulation has shown great potential in the diagnosis and treatment of central nervous system diseases and mental disorders. To improve the accuracy of stimulation in specific brain areas and reduce side effects during the treatment, the geometric structural design of the stimulation coil has...
The over-pressure heat-treatment (OPHT) processed Bi-2212 insert coil technology for high field (> 24 T) magnet systems is based on two critical technologies developed at the National High Magnetic Field Laboratory (NHMFL): optimized OPHT process for high in-field performance (JE ~ 900 A/mm2 at 20 T) and introduction of alumina fiber reinforcement for efficient magnetic stress management. In...
Non-invasive transcranial magnetic stimulation (TMS) is a promising technology for treating many neurological disorders, such as Alzheimer's disease and depression. Since different diseases correspond to different target areas, in order to avoid stimulation of non-target tissues, the stimulation coil generates a focusing induced electrical field in the intracranial target area to achieve...
Compact cyclotrons are required to produce radiopharmaceuticals used in targeted alpha-particle therapy, which is a promising treatment for patients with intractable cancers. To realize a compact cyclotron, we have proposed the Skeleton Cyclotron—an air-core compact cyclotron using high-temperature superconducting (HTS) technology. This cyclotron consists of circular and non-circular coils,...
Abstract：High field nuclear magnetic resonance spectrometer (NMR) is an important scientific instrument in the fields of biology and chemistry, mainly used for qualitative and quantitative analysis of organic and inorganic substance structures. High field NMR superconducting magnets require higher magnetic field strength, smaller magnetic field uniformity, lower magnetic field drift, and...
In heavy ion therapy, reducing not only the radius of the rotating gantry but also the size of the power supplies for the gantry's magnets is crucial to miniaturizing the facility. The rotating gantry primarily consists of several bending magnets and a downstream scanning system. The use of combined-function superconducting magnets and cosine-theta-type combined X-Y scanning magnets has...
A project to develop a compact heavy-ion therapy system has been initiated at the National Institutes for Quantum Science and Technology in Japan. This therapy system uses a 430-MeV/u synchrotron with four 90-degree bending superconducting magnets. The bending magnets have been designed to generate central dipole fields from 0.3 T to 3.5 T at the ramping rate of 0.64 T/s, and each magnet is...
A compact superconducting synchrotron for heavy-ion therapy is under construction at National Institutes for Quantum Science and Technology. This synchrotron is being downsized for widespread applicability in medical facilities using combined-function superconducting magnets for 90-degree main dipoles. The magnetic field of the dipole reaches 3.5 T with a field gradient of 1.5 T/m by...
The SPARC Central Solenoid Model Coil (CSMC) designed and built by Commonwealth Fusion Systems in collaboration with the Massachusetts Institute of Technology Plasma Science and Fusion Center (MIT PSFC) aims to de-risk design aspects of the SPARC CS. One of the main risks associated with the bucked design of the SPARC tokomak is the large loads from the Toroidal Field magnets on the Central...
IO (ITER Organization) planned cold tests for Toroidal Field (TF) and Poloidal Field (PF1) coils, and a test facility is under development for this specific purpose. The TF coil test campaign foresees a series of tests at half operational current and a final one at full current, 68kA. The latter requires a further development of the facility, due to the severity of the test together with a...
The magnet at the core of the EDIPO2 test facility aims at generating a 15 T background field within a 144×144 mm² aperture and maintaining a field homogeneity length of 900 mm (assuming a 1% drop of the field). Its design features two pairs of flat racetrack coils: one pair (vertical coils) located above and below the aperture, and another pair (side coils) located on its sides. All coils are...
This work investigates the potential advantages of using a High-Temperature Superconducting (HTS) Central Solenoid (CS) in the Divertor Tokamak Test (DTT), an Italian nuclear fusion project based in Frascati, Italy, aiming to complete its engineering design phase by 2025 and construction by 2031. To sustain sufficiently long plasma discharges, the project requires a high-performing CS capable...
Fusion magnets for so-called compact high-field machines present a new challenge for designers. Tools for fast assessment of magnet pre-designs are needed, and a new mechanical toolbox called CIRCE has been developed.
New updates to the analysis tool will be presented, including improved winding pack and casing contact, a detailed inner leg interface between adjacent tf coils and...
The design of the DEMO Central Solenoid (CS) poses significant challenges due to the risk of fatigue failure and the stringent design criteria required to mitigate it. These criteria impose constraints on the allowable size of the solenoid, which, in turn, affect the configuration of the toroidal system and influence the overall performance of the fusion reactor. To address these challenges,...
The Levitated Dipole Reactor (LDR) is a promising concept for confining fusion relevant plasmas. In an LDR, a high field dipole magnet (core) is levitated in a large vacuum chamber, mimicking the plasma confinement physics observed in planetary magnetospheres. The performance of an LDR is largely determined by the ability of the core magnet to resist the natural diamagnetic expansion of the...
High-temperature superconducting (HTS) coated conductors (CCs) have become increasingly available for high-field magnet applications, thanks to continual advancements in manufacturing. Previous studies have revealed that HTS CCs, characterized by their anisotropic lattice structures, exhibit a critical current density that strongly depends on the angle between the magnetic field and the tape...
During the operation of rotating motors based on superconducting coils, impregnation is used to enhance the mechanical integrity against rotational vibration and to protect the superconducting coils from mechanical disturbances in strong magnetic fields. Generally, epoxy resin is primarily used for high-temperature superconducting (HTS) coil impregnation because of its low cost, excellent...
The fabrication of superconducting coils using high-temperature superconductor (HTS) tape necessitates the use of soldering processes to join sections of tape or to connect the tape to the current lead. During this process, flux is commonly used to remove the oxide layer from the copper stabilizer to improve the soldering quality. However, residual flux remaining on the surface or permeating...
The design and development of quench detection for the CFETR TF prototype coil is in progress, which is expected to be completed in the fourth quarter of 2025. According to the quench simulation analysis, the voltage detection with a threshold of 200 mV and a delay of 2 s satisfies the quench detection design criteria, that is, the hotspot temperature is less than 150 K. The foundation of a...
To achieve magnetic fields above 20 T in modern magnets for fusion devices and high-energy physics accelerators, the use of high-temperature superconductors (HTS) at low temperatures below 20 K is proposed. In recent years, there has been active development of increasingly larger HTS coil systems. However, as the size of the magnets increases, the issues of stability and protection for these...
Accurate simulations of quench events in high temperature superconducting (HTS) tapes, cables and magnets often rely on complex finite element models (FEM) and the challenges for such simulations are well known. The non-linear properties and high-aspect ratio mesh of HTS tapes lead to poor convergence of the models, especially near a quench event. At the superconducting-to-normal transition,...
A magnet undergoing a quench is one of the most challenging scenarios for any operator, often leading to potential failure of the magnet. While quench phenomena are well understood in LTS magnets—where manufacturers deliberately induce quenches during commissioning to ensure reliability—the same cannot be said for HTS magnets. Challenges such as the slow propagation of the normal zone and a...
The high current density of ReBCO conductors at elevated fields makes them particularly suitable for high-field applications. One of the key challenges in the design of high-field ReBCO devices is effective quench detection and protection, making it crucial to investigate the magnetic field-dependent quench behavior of ReBCO conductors. The minimum quench energy (MQE) is known to decrease with...
Screening currents on REBCO magnets are well known as causes of troublesome. The screening current-induced fields cause a low quality; i.e., it deteriorates the field homogeneity or generate unexpected fields. In recent years, the local high strain effect due to screening currents has been investigated. The screening current under high magnetic fields rotate REBCO tapes. It results the REBCO...
High-temperature superconducting (HTS) magnets are essential for advanced applications such as particle accelerators and fusion reactors, requiring effective quench management to ensure safety and performance. No-insulation (NI) coils, which allow current to move between turns during quench events, are commonly used in HTS magnet design. However, the contact conditions between turns in NI...
Active quench protection systems in large superconducting magnets rely on the rapid and efficient delivery of heat from quench heaters to the magnet windings to initiate a controlled quench. However, thermal diffusion is significantly influenced by the multi-layered electrical insulation, thermal barriers, and contact resistance between surfaces. This work presents simulation results that...
High temperature superconductor (HTS) magnet systems, especially those designed for fusion reactors, require effective and reliable monitoring to avoid damaging anomalies. In tokamaks, some of the magnetic coils are time dependent, which cause additional strain and electromagnetic effects within the magnet system. Ionizing radiation can also lead to non-uniform degradation of conductors. The...
This paper presents the quench test results and analysis of no-insulation (NI) REBCO (Rare-Earth Barium Copper Oxide) double pancake racetrack coils under conduction cooling conditions. Two racetrack coils, differing in dimensions and number of turns (280 and 488 turns), were tested at a temperature of 50 K each. The current was ramped up to their critical values until quenching occurred,...
REBCO tapes are promising material for the
construction of high field magnets because of large engineering
critical current densities at high field, however, the slow normal zone propagation velocity (NZPV) makes the protection against
quenches a critical issue. Stability margin of REBCO cables is
two or three orders of magnitude greater than that of lowtemperature superconducting cables,...
The results of numerical and experimental studies of fundamentals of the quench monitoring technique based on frequency and time domain reflectometry (FTDR) are discussed. To carry out fast (real time) monitoring of the coolant gas temperature and thus to observe evolution and prevent the quenching in superconducting (SC) magnets the techniques of detection and analysis of microwave...
High temperature superconducting (HTS) accelerator magnets can achieve higher magnetic field with higher current capacity. However, with the shielding current effect of the HTS materials, the current distribution inside REBCO tape will deviate from uniform current assumption, which results in a higher sextupole field harmonics. To compensate sextupole harmonic field in the accelerator magnet...
A new testing facility employing a 15-T transverse field to access the full-service-field characteristics of superconducting materials is now under development in China. A primary objective involves producing a large bore 15-T dipole magnet to serve as the source of the transverse magnetic field load. The magnet consists of a Low-Temperature Superconducting (LTS) dipole magnet providing 12 T...
In the framework of the U.S. Magnet Development Program, LBNL is planning to fabricate a high field hybrid magnet combining Nb3Sn and Bi-2212 dipole magnets. The Nb3Sn outsert will be a four-coil canted cosine theta (CCT) dipole magnet, designed to generate 14 T in a 120 mm bore diameter. The Bi-2212 insert aims to achieve the highest field possible in a 40-45 mm diameter bore. Coil designs...
This study presents the conduction-cooled current injection design/thermal gradient and cyclic testing for a ReBCO canted cos-theta magnet designed and Fabricated by LBNL (magnet C2). This coil has been measured at 77 K (LN2) and 4.2 K (liquid helium), as previously reported by LBNL, but in this case, we used a large conduction cooled cryostat available at OSU. Testing this coil in a...
Magnet systems of particle accelerators consist of many various types of magnets. There is an interest in replacing rather low-field conventional resistive magnets with high-temperature superconducting (HTS) magnets. The main goal is to reduce operational expenses which is critical during the continuously increasing cost of electricity. At Fermilab were built and successfully tested several...
High-temperature superconducting (HTS) magnets, with their superior current-carrying capacity and high operating temperatures, have shown considerable potential for applications in medical imaging, particle accelerators, power transmission, and scientific instrumentation. However, HTS coated conductors (CCS) are susceptible to significant shielding current effects due to their high aspect...
With the widespread application of high-temperature superconducting (HTS) REBCO tapes in fields such as energy, healthcare, and transportation, their operating environments have become increasingly complex, placing higher demands on their operational stability. Although the multi-filamentary REBCO tapes can improve the electromagnetic performance, specific metals and compounds in REBCO tapes...
This paper examines the potential of epoxy-based soft magnetic powder cores (SMPC) for electric motor applications. SMPC, created by uniformly dispersing iron-based ferromagnetic powder into epoxy resin, effectively reduces eddy current losses and decreases magnetic anisotropy, resulting in more uniform magnetic properties. Although SMPCs exhibit lower permeability compared to conventional...
An organic olefin-based thermosetting dicyclopentadiene (DCP) resin is commercially available in Japan as TELENE® from RIMTEC Corporation, and its viscosity is less than one-tenth that of the CTD-101K® epoxy resin. In previous studies, the TELENE® can withstand greater strain than CTD-101K® and can achieve higher heat capacity when mixed with ceramic powders from a previous study. The use of...
Commonwealth Fusion Systems (CFS) is currently developing and building a commercially relevant fusion energy machine that will produce more energy than is put into it (SPARC). In this research, an insulation that electrically isolates the toroidal field (TF) magnets from each other is being tested to determine its behavior, evolution, and failure rate during the shear displacement and high...
Progress on NI-coil design for EU DEMO
M.Ortino, N. Bykovskiy
École Polytechnique Fédérale de Lausanne (EPFL), Swiss Plasma Center (SPC),
CH-5232 Villigen PSI, Switzerland.
This study presents the latest results of a 3D original Matlab code, developed for simulating in a fast fashion the charge/discharge of a EUROfusion DEMO toroidal field (TF) coil, by especially coupling both...
Bi-2212 multi-filament round wire is a high-field capable, isotropic conductor that does not experience the large screening-current stresses suffered by ReBCO. Together with its high current carrying capabilities, Bi-2212 is a very promising candidate for compact high-field/high-homogeneity magnets. Superconducting coils tend to experience large mechanical stresses under operating conditions....
By using TELENE® resin as superconducting magnet impregnation material, training and magnet retraining after a thermal cycle were nearly eliminated in Nb3Sn undulators. This allows reducing operation margins in light sources, and increasing the on-axis magnetic field, thereby expanding energy range and brightness intensity. TELENE is Co-60 gamma radiation resistant up to 7-8 MGy, and therefore...
High-temperature superconducting (HTS) rare-earth barium copper oxide (REBCO) magnets are typically fabricated in a stacked configuration of pancake coils. Conventionally, the electrical connections between pancake coils is achieved by joining the REBCO splice with soldering process. In this process, solder flux is applied to remove oxide layer on the REBCO tape surface and to enhance solder...
There remains an urgent need for higher thermal conductivity electrical insulation for high steady-state thermally loaded superconducting and cryoresistive electromagnets, such as those used for fusion, undulator light sources, particle colliders, and alternating-current operated electric machines. Polymeric materials, which are currently used, demonstrate degraded thermal conductivity at...
Rare-earth barium copper oxide (ReBCO) coated conductors (CCs) are considered promising materials for high-performance cables and high-field accelerator magnet design. ReBCO tape-wound magnets with no insulation between tapes were designed to protect themselves from thermal instability through a current-sharing mechanism. However, they face challenges such as insufficient mechanical support...
Superconducting magnetic energy storage (SMES) is a promising candidate for electric power compensation. The target applications of SMES are widely covered with voltage sag, instant shortage, power stabilization, frequency control, load fluctuation, and load leveling. High-temperature superconductors are expected to reduce refrigeration energy requirements for superconducting coils....
To fulfill the demand for high-performance magnetic fields in extreme environments, such as those found in maglev trains, the implementation of superconducting magnets with high cur-rent-carrying density offers a lightweight alternative to traditional copper or permanent magnets. This is particularly significant for enhancing the safety and cost-effectiveness of high-speed maglev trains. In...
For the situation of energy compensation that needs several kA level current capacities, we developed a high temperature superconducting magnetic energy storage system. This HTS SMES system can fill the gap in research on superconducting energy storage systems in the field of high current-carrying energy compensation. The SMES coil consists of 8 sub-solenoid coils serially connected with each...
Pulsed power applications, such as pulsed-field magnets, electromagnetic launchers, and fusion experiments, require high-performance, efficient, and compact energy storage systems. These applications demand large amounts of energy in short bursts, often at high rates, which traditional energy storage technologies cannot support effectively or are highly inefficient. Superconducting Magnetic...
High-temperature superconducting (HTS) maglev has the advantages of strong suspension ability, high speed, and low operating cost, which is an important candidate technology for future high-speed rail transportation, and the on-board HTS magnet is one of its core components. In recent years, metal-insulated (MI) winding technology has brought better mechanical stability and good...
The POSEIDON project, funded by the European Union, seeks to develop an HTS Superconducting Magnetic Energy Storage (SMES) systems for maritime applications. A key challenge in this endeavor is the accurate modeling of AC losses, which represent a major heat load on the cryogenic system and critically influence system optimization. This study presents a novel numerical model based on the...
The V-ACCESS (Vessel Advanced Clustered and Coordinated Energy Storage Systems) project brings together expertise on supercapacitors, superconductive magnetic energy storage systems (SMES), design and control of shipboard power systems, power electronics, lifetime cycle analysis, and ship classification to increase the technology readiness level (TRL) of hybrid storage systems, i.e. combining...
Faraday Factory Japan (FFJ) has established itself as a leader in the second generation of high-temperature superconducting (2G-HTS) wire production through continuous advancements in manufacturing capacity, innovative technology, and research excellence. In 2024, FFJ commissioned a state-of-the-art facility in Zama (Japan), enabling the production of over 1,000 kilometers of 12 mm...
Eliminating quench training in superconducting accelerator magnets requires understanding the underlying mechanical transients, which include cracking of the impregnation material, interfacial debonding between the impregnation material and conductor, and slip-stick conductor motion; these events can release heat and lead to premature quenching and training. Earlier, we developed a system...
At the heart of the High-Luminosity project (HL-LHC) of the CERN Large Hadron Collider (LHC), new low-beta* Nb$_3$Sn superconducting quadrupole magnets will be installed on each side of the ATLAS and CMS experiments. Half of these magnets are built by CERN and are called MQXFB. A total of 12 MQXFB magnets are being constructed: two to be installed in the IT String facility, for systems...
Quenches are a major issue for superconducting magnets because of their high current density which translates to high stored magnetic energy and eventually heat dissipation that may cause irreversible damage if left unadressed. Designing a well-protected magnet against quenches is one of the key considerations in the design. The objective of this paper is to describe the experimental...
The US High-Luminosity LHC Accelerator Upgrade Project (AUP) is responsible for delivering cryo-assemblies for the Q1/Q3 quadrupole optical components of the High Luminosity LHC upgrade at CERN. Total of 10 cryo-assemblies containing two Nb3Sn quadrupole magnets per cold mass will be delivered within this program. After the successful test of the first pre-series cryo-assembly in 2023, two...
The installation and maintenance of components within the vacuum vessel (VV) of fusion power plants (FPPs) are heavily constrained by access limitations. In current magnetic confinement fusion experiments, access is typically restricted to the space between magnetic coils, significantly limiting the size of components that can be installed or maintained. These constraints are even more...
We present a modeling framework to evaluate the feasibility of using a close-coupled-secondary (CCS) for quench protection of stellarator magnets. Foreseen compact stellarator fusion reactors feature non-planar high-temperature-superconductor (HTS) coils with a large stored magnet energy, on the order of 100 GJ. Safely extracting this energy in case of a quench requires avoiding excessive...
The production of the MQXFA low-beta quadrupole magnets for the High Luminosity LHC (HL-LHC) is quite advanced with about 20 magnets cold tested in a vertical cryostat. The MQXFA magnets are fabricated by the US HL-LHC Accelerator Upgrade Project (AUP) and are being used in the Q1 and Q3 Inner Triplet (IT) elements of the HL-LHC, whereas CERN is fabricating similar magnets for Q2a and Q2b IT...
We have developed a new fast quench detection method for superconducting devices utilizing the REBCO superconductor tape itself as a microwave transmission line. Unlike voltage detection where the signal is proportional to the length of the normal zone, a 100-m-long transmission line will effectively become two 50-m transmission lines if quench occurs midway along the tape, joined by a...
The High-Luminosity upgrade of the LHC at CERN requires 32 new cryo-assemblies to be installed around the interaction points 1 and 5. They incorporate 90 magnets of various types, and in addition several prototypes and spares are built. The magnets are produced within the HL-LHC project, and a large part is tested at CERN. Most of the magnets are tested first in standalone configuration in a...
The Spherical Tokamak for Energy Production (STEP) is a prototype fusion power plant, planned to be operational in the 2040s. STEP TF coils consist of cables operating at 90kA of current with a peak-field on coil of 16T. These cables are jointed together through a remountable interface at multiple locations in the coil pack which allow for remote maintenance. The joints are intended to operate...
The development of high-field magnets using high-temperature superconductors (HTS) presents significant challenges, particularly in quench detection and protection. Due to the inherently slow quench propagation in HTS, conventional detection and protection methods may be ineffective. To address these challenges, novel approaches are being explored by the magnet community. A possible method...
The High-Luminosity LHC (HL-LHC) upgrade aims to increase the colliders integrated luminosity by an order of magnitude through significant modifications to the interaction region layout. One of the key hardware components involved in this upgrade is the MBRD combination-recombination dipole, a double-aperture magnet with magnetic fields aligned in both bores. For this magnet, a magnetic field...
There are many applications, companies and institutes pursuing and building large and high field REBCO magnets for a variety of applications, for example the toroidal field coils of a tokamak. Using a classical external dump for discharge and quench protection presents several problems, such as very high voltages. Whether or not these magnets can be protected using internal non-insulation or...
Quench detection is a crucial technology that enables using HTS conductors in high-field magnets for high-energy physics and fusion applications. At the same time, hot spot localization capability provides valuable insights to magnet developers and operators. Distributed temperature sensing along the conductor path can achieve both goals and is especially suitable for fast-ramping magnets or...
MCBXF magnets are orbit correctors for the High-Luminosity (HL) Large Hadron Collider (LHC) upgrade. The magnet design consists of two nested dipoles, with an aperture of 150 mm. The magnets have been designed in two physical lengths, namely of 2.5 m (MCBXFA) and 1.5 m (MCBXFB), with the same cross section. The series production of the magnets consists of 6 long and 11 short magnets and being...
KEK have so far tested four series beam separation dipoles, a.k.a. D1 (MBXF) magnets, for the High Luminosity LHC upgrade (HL-LHC). The magnet is wound on Nb-Ti Rutherford cables and designed to operate at 1.9 K generating a central field of 5.6 T with a magnetic length of 6.3 m, which corresponds to a field integral of 35 Tm. All the series magnets were subjected to a quench training campaign...
ITER project has decided mid 2023, to procure a Magnet Cold Test Facility (MCTF) to test as many as possible Toroidal Field Coils (TFC) and the Poloidal Field Coil PF1, before they will be assembled in the tokamak. An important constraint is that the coil tests shall not impact the tokamak construction. The earliest readiness of the facility is then very important factor to optimize its usage...
Neoscan Solutions is currently building the 14T HTS MRI magnet for whole-body MR imaging and spectroscopy, under the supervision of a magnet committee formed by the DYNAMIC consortium, i.e. seven research institutes and medical centers in the Netherlands who will be using the system. The magnet will be sited at the Radboud University in Nijmegen. It offers an 82 cm wide warm bore for MRI of...
The quest to produce energy from fusion power with magnetic confinement follows two main lines of research and development, as far as the generation of the magnetic field is concerned. On the one hand, several national and international roadmaps to fusion rely on tokamak designs obtained scaling up ITER, i.e. based on low temperature superconducting (LTS) magnets. The use of high temperature...
A CNRS-CEA French collaboration has developed and built a new modular hybrid magnet at LNCMI-Grenoble to provide intense magnetic fields and fluxes. It was designed to reach in its main configuration at least 43 T in a 34 mm warm bore aperture with 24 MW of electrical power. This is achieved by combining resistive inserts, including Cu-alloy polyhelix (25.5 T) and Bitter coils (9 T), with a...
SPARC is a compact, high-field tokamak based on high temperature superconductor (HTS) magnets developed by Commonwealth Fusion Systems and the Massachusetts Institute of Technology. This research explores the mechanical and electromagnetic behavior of SPARC’s cable-based magnet systems, namely the Central Solenoid (CS), the Poloidal Field Coils (PF), and the feeder (FEED) systems. Our studies...
Fermi National Accelerator Laboratory (Fermilab) is constructing a new High Field Vertical Magnet Test Facility (HFVMTF) with capabilities comparable to the European facilities EDIPO and FRESCA2. The facility, located at Fermilab, will feature a background magnetic field of 15 T, generated by a magnet provided by Lawrence Berkeley National Laboratory (LBNL). The HFVMTF will support two U.S....
The Dresden High Magnetic Field Laboratory (HLD), a member of the European Magnetic Field Laboratory (EMFL), is a pulsed-field user facility that allows external and internal researchers to perform a wide range of experiments in pulsed magnetic fields [1]. Taking advantage of two independent, modular 50 and 14 MJ capacitor banks with charging voltages up to 24 kV, we operate a large variety of...
The High-Temperature Superconducting (HTS) magnet is being developed for the fusion reactor magnets. One of the options for the large-current HTS conductor is a simple stacking type in which REBCO tapes are stacked without twisting or transposing.
The Stacked Tapes Assembled in Rigid Structure (STARS) conductor has been developed at the National Institute for Fusion Science (NIFS) since...
Over the past two decades, the SULTAN test facility at EPFL-SPC has qualified superconductors for all major superconducting fusion facilities worldwide. However, the increasing demand for higher field and higher current conductors—partly driven by the development of High Temperature Superconductors —requires testing capabilities beyond those of SULTAN (limited to a background field of ≤11 T...
The Laboratoire National des Champs Magnétiques Intenses (LNCMI) is a French host facility for experiments in high magnetic fields. LNCMI is a member of the European Magnetic Field Laboratory (EMFL) with the Hochfeld-Magnetlabor in Dresden (HLD) and High Field Magnet Laboratory in Nijmegen (HFML). Based on two sites, the LNCMI offers routinely static magnetic fields up to 37 T at its Grenoble...
Significant efforts to advance high temperature superconductor (HTS) and HTS coil technology are underway by privately funded startups with the goal to demonstrate HTS maturity for commercial fusion. The goal for a fusion pilot plant (FPP) is to make 50-100 MW net electricity power plants with either extended long pulses or steady state options. Although a high current, self-field test...
The National High Magnetic Field Laboratory (NHMFL) – Pulsed Field Facility (PFF) at Los Alamos operates ten pulsed magnet stations that deliver magnetic fields up to 100 T for user experiments. In recent years, PFF has enhanced its capabilities with upgraded magnets, enabling the generation of higher magnetic fields and an increased number of pulses. This presentation will provide an overview...
High Field Compact Machine Approach to Fusion and Relevant Superconducting Technologies*
B. Coppi1, L. Sugiyama1 and C. Mazzotta2
1MIT (US), 2ENEA (Italy)
Given the limitations of relevant theory and available experimental results at the current stage of fusion research, reaching regimes close to ignition conditions is necessary in order to investigate the physics of meaningful fusion...
The need for strong steady state magnetic fields, of 40 T and above, raises several new challenges in the design of superconducting magnets. Rare-earth barium copper oxide (REBCO) coated conductors (CCs) are nowadays the strongest candidates for this type of applications, yet the layered structure of these materials carries along the major mechanical challenges. Recent tests of ultra-high...
REBCO CC (Rare-earth barium copper oxide coated conductors) are the best candidate materials for superconducting TORT (tapes on round tube) cables and high-field magnets due to their excellent mechanical strength, high current-carrying capacity, and magnetic strength. It is currently known that the AC (alternating current) loss can be decreased when TORT cables are made using REBCO...
• Tokamak Energy is pursuing commercial fusion energy based on the development of spherical tokamaks with high temperature superconducting (HTS) magnets.
• The Demo4 project is an ambitious high field HTS magnet build that has delivered a full spherical tokamak magnet system. This will provide a world first demonstration of the operation of a representative array of coils in a toroidal and...
Research on high-field all-superconducting magnets has garnered significant global attention in recent years due to their reduced size, lower cost, and enhanced convenience compared to hybrid magnet systems. These magnets play a pivotal role in various research fields, including material science, biological studies, and quantum computing. However, the fabrication of high-field superconducting...
As the high critical current at high field, the representative second-generation high-temperature superconductor (2G HTS) ReBCO serves as a good candidate for future fusion devices, i.e. the Chinese fusion engineering test reactor (CFETR), the Demonstration Power Station (DEMO) with magnet field higher than 15T. The main goal of CFETR is to build a fusion engineering tokamak reactor with a...
The SPARC compact, high-field tokamak developed by Commonwealth Fusion Systems and the Massachusetts Institute of Technology is based on high temperature superconductor (HTS) magnets. This device employs 8 Poloidal Field PF magnets which are made with PIT-VIPER cable wound in pancakes, the smallest measuring 1.2 meters radius, and the largest 8 meters. There are 10-14 pancakes in each magnet,...
In September 2024, the 42 T resistive magnet at The High Magnetic Field Laboratory of Chinese Academy of Sciences (CHMFL) was successfully commissioned, and in October, it was opened for user experiments. This paper provides a detailed account of the commissioning process and systematically investigates the evolution of critical parameters, including coil voltage and water flow rate,...
abstract pending
We introduced internal oxidation in Rod-in-Tube (RIT) Nb3Sn subelements, used in simplified restacked wire, by using SnO2 powders as an oxygen source (OS). During Nb3Sn synthesis, the OS decomposed, resulting in a grain size below 60 nm. This grain refinement is consistent with an increase of the critical current density (Jc) towards the performance...
Magnetisation losses of Roebel cable samples with striated REBCO strands were measured at different temperatures between 4K and 85K in ac magnetic fields up to 0.2T. While the losses of Roebel cables with non-striated strands were shown previously in quantitative agreement with the losses of magnetically coupled two side-by-side tape stacks as thin Norris' strips, significantly differences in...
We have proposed “Robust REBCO coil” concept for high field cryogen-free superconducting magnet (CSM), which consists of two REBCO tapes co-winding and edge-impregnation. It is expected that the two tapes co-winding in direct electric contact can reduce the risk of burn-out coming from local degradations and the edge-impregnation reduce the maximum hoop stress [1-3]. From an electromagnetic...
The National Institute for Materials Science (NIMS) is ongoing the R&D on ultrafine Nb3Sn superconducting wires less than 50 microns in diameter. So far, we have successfully fabricated a kilometer-scale of Nb3Sn ultrafine wire through the bronze process. The starting billet was assembled by 19 Nb rods, a bronze alloy matrix of Cu-14%Sn-0.3%Ti. The outer diameter of the starting billet is...
Narrowed high-temperature superconducting (HTS) tapes have much smaller hysteresis loss and eddy current loss per unit tape width according to analytical and experimental data. Multi-filamentary technology is widely recognized as an effectively way of reducing the AC loss of HTS tapes by cutting each tape into multiple narrower filaments while maintaining the whole structure. But the magnetic...
We present an update on the ongoing development of the MIT 1.3-GHz nuclear magnetic resonance (NMR) magnet system (1.3G). The 1.3G consists of a 19.6-T (835-MHz) high-temperature superconducting (HTS) REBCO insert magnet (H835) and an 11.7-T (500-MHz) low-temperature superconducting (LTS) background magnet (L500). These two magnets are coaxially aligned and independently powered to generate a...
Novel ultrafine jelly roll Nb3Sn ultrafine wires, i.e. ~50 μm diameter, offer the potential of building Nb3Sn magnets using the react-and-wind approach with high-Jc wires. The high flexibility of these wires due to their small diameter, the ability to assemble multiple of them in Rutherford cables, and the long unit lengths that have recently been manufactured motivates further studying the...
The Spiral Copper-plated Striated Coated-conductor cable (SCSC cable) is our novel concept of high current cable with low ac loss, in which copper-plated multifilament (striated) coated conductors are wound spirally on a metal core in multiple layers. Whereas copper-plating allows current sharing among filaments against local defects in a filament, filaments are decoupled electromagnetically...
The Large Scale Coil (LSC) is a high-temperature superconducting (HTS) coil that has been developed and tested in the research and development efforts for the 40-T All-Superconducting Magnet Project at the National High Magnetic Field Laboratory. The LSC is composed of stacked pancake disks consisting of 2-in-hand wound rare-earth barium copper oxide coated conductor (CC REBCO) tapes with...
Superconducting magnets in particle accelerators currently use mostly a Nb-Ti alloy, which has a critical temperature (𝑇𝑐) of 9.2 K and a critical field (𝐵𝑐2) of 14.5 T. However, future particle accelerators, such as those beyond the LHC, will require dipole magnets capable of generating fields of 16 T or higher. This necessitates a shift to high-performance superconductors, with the...
CORC, STAR, and in general, conductors consisting of a set of helically wound conductors on a round core are of substantial interest for use in High Energy Physics accelerator magnets because of their high Bc2 and excellent transport properties in high fields. Their magnetization properties as well as their AC loss are also of interest, because they can cause particle beam defocusing and...
Ultra-high field magnets are being developed for various applications in fundamental-physics experiments, materials sciences, and nuclear magnetic resonance (NMR). Here we report our recent R&D work focused on conceptual design and enabling technologies for a 40 T all-superconducting solenoid magnet with a 20-mm warn bore, intended for potential high-energy partial physics experiments....
Proposed 14 T Nb3Sn magnet designs for a future energy-frontier circular collider often call for wires with higher Jc, larger diameter and lower copper to non-copper (Cu:nonCu) ratio. As well as pushing Nb3Sn superconducting wire technology to its performance limits, these characteristics all prove challenging for magneto-thermal stability.
This study investigates the stability of Nb3Sn wires...
This study investigates the magnetization of ReBCO cables, utilizing experimental measurements in magnetic fields up to 30 T at 4.2 K. The cable is comprised of 29 ReBCO tapes, with a cable OD of 3.63 mm and cable pitch of 7.16 mm. The tapes were 2 mm wide and had a substrate thickness of 30 μm, and a Cu plating thickness of 5 μm. The cable had an Ic of 1675 A at 77 K and self-field. The ReBCO...
Princeton Plasma Physics Laboratory is advancing the development of large-bore, high-field, high-temperature superconducting (HTS) magnets to support cutting-edge physics research at Princeton University (PU). A 3-phase REBCO magnet program was initiated to address critical challenges and develop essential technologies for HTS magnet development. In Phase 1, we established the HTS research...
To develop superconducting wires suitable for applications demanding extremely high magnetic fields, we conducted an experimental investigation on the optimization of microstructure and heat treatment processes aimed at enhancing the critical current density (non-Cu Jc) at 16 T in Internal-tin type multifilamentary Nb3Sn superconducting wires fabricated in WST. Utilizing comprehensive...
This presentation reports AC loss study for parallel-wound HTS coils used for AC applications, e.g. fusion PF coil and rotational machines. The reason for parallel winding is to increase the current rating of winding without increasing too much the winding inductance. We made several four-conductor parallelly wound HTS coils and measured both the current distribution and AC loss. Our...
REBCO HTS material makes it possible to consider very high engineering current densities in coil windings even above 10 T with operation temperatures up to 30 K. In this work, we present the design of a 500 mm bore split-coil magnet made of two stacks of REBCO double-pancakes. It is developed as a platform offering eihter 10 T in a mid-plane room temperature bore for magneto-science, or up to...
MgB2 is one of the practical superconductors that has been widely studied over the past two decades. The internal magnesium diffusion (IMD) method serves as a promising method because it can enhance the grain connectivity of MgB2 phase and thereby improve the superconducting current of MgB2 wires. In this work, we successfuly fabricate the km-class 30-filament MgB2 wires using the IMD method,...
High-current HTS cables made of stacked REBCO tapes are being considered for large superconducting magnet systems for fusion and other applications. AC losses are critical when analyzing a stack of non-insulated tapes. Using finite element software such as COMSOL, it is possible to model a 3D stack of non-insulated REBCO tapes and assess how AC losses vary, depending on factors such as the...
YBCO is one of the best choices for high field superconducting magnets due to its high current carrying capacity. We present a highly compact no-insulation (NI) magnet wound with 45-micrometer-thick YBCO high temperature superconducting (HTS) tape. A YBCO magnet with one double pancake (DP) coil generated a direct-current magnetic field of 28.20-tesla (the current is 740.4 A), the highest...
Commercially available Nb₃Sn wires with high critical current density are commonly used to manufacture high-field magnets (greater than 10T). To improve their current-carrying capacity, various types of Nb₃Sn wires have been developed. However, as the critical current increases, drawing the Nb₃Sn wire becomes more difficult, leading to larger filament sizes (on the order of hundreds of...
Reducing AC loss in high-temperature superconducting (HTS) coils is critical in HTS applications such as SMES (superconducting magnetic energy storage) and fast ramping magnets. One effective approach is applying magnetic flux diverters to reshape the magnetic field distribution in the vicinity of end coils/windings. However, the benefits of MFDs diminish in high magnetic fields that exceed...
Fusion magnets in deuterium-tritium based power plants will experience bombardment by high energy neutrons during operation. This is a particular severe problem for REBCO-based compact high-field fusion reactors. The fusion magnets in these devices will typically be operated at around 20 K and accumulate radiation damage at this very temperature.
We have commissioned a cryogenic ion...
Project 8 aims at measurement of the absolute neutrino mass using tritium, by precisely measuring the energies of the beta-decay electrons in the high-energy tail of the spectrum. A trap for atomic tritium is envisaged using a Ioffe magnet, which is discussed in this paper. The fundamental requirement is to trap atomic tritium within a large microwave cavity for cyclotron radiation emission...
The hybrid superconducting resistive magnet (M8) in Grenoble has reached an important milestone in 2024 : 42T was reached in a cold bore of 34mm. The first experiments are planned in 2025.
The experimental setup which had allowed to reach this important milestone will be described, as well as the tests which were done in the commissioning phase. This hybrid magnet is planned to be integrated...
Several superconducting electron cyclotron resonance (ECR) ion sources for heavy ion accelerators are in operation around the world. These rely primarily on magnets wound using Nb-Ti conductors. Development toward the use of Nb$_{3}$Sn conductor as an alternative conductor is advancing, with higher magnetic field limits resulting in higher intensity high charge beams being a primary...
The High Magnetic Field Laboratory of Chinese Academy of Sciences (CHMFL) aims to develop steady high magnetic field magnets and promote fundamental sciences on the magnets. To develop hybrid magnets is one of its main goals. A hybrid magnet is usually composed of a superconducting magnet and a resistive magnet. The first hybrid magnet in CHMFL was established in 2017, with a resistive magnet...
Strong efforts to develop magnets for compact fusion reactors using coated conductors (CC) are presently underway. To determine the operational lifetime of fusion magnets, it is necessary to know the effects of radiation damage on the critical current density J$_c$ of the CC. According to plans, fusion magnets will operate between 10 and 30 K in a background field up to 20 T. As portions of...
Superconducting magnets for SIS100 and Super-FRS - project progress
The heavy ion synchrotron SIS100 and the fragment separator Super-FRS form the central elements of the novel accelerator facility FAIR at Darmstadt, Germany. In both machines, superconducting magnets are utilised for the ion-optical lattice.
Currently, the production and testing of the magnet series are ongoing involving...
The French government has recently launched the SupraFusion Research Program lead by CEA and CNRS with the partnership of multiple other national laboratories and universities. This national program has been granted 50 M€ in order to boost the development of HTS superconductors technology towards large societal applications, using the vector of nuclear fusion as a powerful driver for this...
As part of the FAIR project and within the GSI and CERN collaboration, the superferric magnet production series —key components of the Superconducting FRagment Separator (SuperFRS) under construction at FAIR, Darmstadt, Germany— are undergoing rigorous testing at CERN in a dedicated cryogenics test facility.
The tested magnets include dipoles and various types of multiplets (composed of...
The National High Magnetic Field Laboratory (MagLab) operates high field user facilities in Tallahassee (dc, NMR, EMR, ICR) and Gainesville (MRI, HiB/T), Florida, and Los Alamos, New Mexico (pulsed). These facilities serve approximately 2,000 scientists every year. The recent arrival of ultra-high field magnets based on the high temperature superconductors (HTS) is expected to impact most of...
The new type of insulation where metals, varistors on more in general media with a change in resistivity are called “smart insulation”. Among the latter, metal-to-insulator transition (MIT) materials have lately collected interest, since one could get both the advantage of a full insulation during charge/operation (low T) and hot-spot redistribution during a quench (high T).
In this respect,...
We present our work on the HTS4 project, part of the CHART framework and the FCC Feasibility Study, on energy-efficient nested HTS magnets for FCC-ee. By replacing the normal conducting sextupole and quadrupole magnets in the 2900 short straight sections by HTS nested variants, significant amounts of energy can be saved. This follows from 1) avoiding ohmic dissipation in the sextupoles and...
The Wuhan National High Magnetic Field Center at Huazhong University of Science and Technology China is one of the premier facilities worldwide for conducting experiments at pulsed high magnetic fields. The Center has been operational for 13 years. Currently, a 28 MJ capacitor bank consisting of 22 modules of 1.2 MJ each and 2 modules of 800 kJ each as well as a 100 MJ/100 MVA...
The DTT magnetic system is mainly constituted by the following superconducting coil sets: 18 Toroidal Field (TF) magnets, 6 external Poloidal Field (PF) coils and a stack of 6 independently fed Central Solenoid (CS) modules. The PF coils system, characterized by a full top-down symmetry, is realized in Nb3Sn (PF1 and PF6) and NbTi (PF2, PF3, PF4 and PF5). This work is focused on the SULTAN...
The Innovative Research Infrastructure on Applied Superconductivity (IRIS) is a project funded by the Italian Minister for University and Research, with leadership assigned to INFN, and LASA laboratory serving as its coordinator. This project, currently in its final phase, involves the design and construction of an Energy Saving, fully high-temperature superconducting dipole Magnet for...
An extensive experimental campaign to study the evolution of the quench in REBCO conductors has been carried out within the EU-DEMO programme, motivated by the use of High Temperature Superconducting (HTS) conductors in the Central Solenoid (CS). The aim was to explore the quench initiation and propagation in different conditions in HTS conductors based on stacked tapes layout. Seven...
High-Temperature Superconductors (HTS) technology offers significant advantages in reactor design, representing a key step toward commercial fusion power plants. These advancements have driven extensive R&D efforts on HTS conductors for fusion magnets based on Rare Earth-Barium-Copper-Oxide (REBCO) tapes.
The aluminum slotted-core cable concept developed by ENEA features stacks of HTS tapes...
The aim of providing high collision energy for future particle accelerators relies on the capability to design and demonstrate the feasibility of 20 T dipole magnets. To reach the ambitious goal of a future proton-proton collider, a coordinated effort is required to overcome the current technological limits. The US Magnet Development Program is exploring the hybrid magnets option to reduce the...
Magnet technologies employing REBCO high temperature superconductors (HTS) have bloomed over the last decade. Many flagship projects are pushing HTS technologies to the boundaries of achieving reliable high magnetic field. Nevertheless, quench protection of an HTS magnet remains a challenge for designers, which must be addressed to enable more practical applications of HTS magnets. That is,...
The use of high temperature superconductors (HTS) in magnetic levitation (Maglev) has been investigated for decades. Superconducting materials may be used in both the propulsion and levitation subsystems of a device. For the propulsion subsystem, their use in electric machinery potentially reduces losses and increases the power to volume or mass ratio. For the levitation subsystems, they are...
The aviation sector’s greenhouse gas emissions could be reduced by replacing jet engines with electric motor-driven propellers. However, the high power required of these motors is possible only by increasing the motor size and/or the current it carries. Larger size means more mass, which would reduce the plane’s range and payload capability. Higher current means more heat generated by...
Superconducting wind generators provide significant advantages in terms of power density over conventional wind generators, resulting in reduced weights and volumes, which contribute to significant cost reduction in the installation and maintenance of offshore wind turbines. An efficient cryogenic cooling system is crucial to ensure the safe and stable operation of low-temperature...
The field of applied superconductivity is on the brink of a transformative evolution, driven by the rapid advancements in artificial intelligence (AI). Historically rooted in physics, material engineering, and electrical engineering through experimental tests at cryogenic temperature, deterministic methods and rigorous mathematical modelling, superconductivity now face the necessity of...
