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 provides access and supports more than 100 scientific projects annually. At the HLD, such diverse...
Fast ramping magnets are important accelerator components in several areas. In High Energy Physics they are needed in an accelerator ring for a Muon Collider, in booster accelerators for other colliders, and for production of high-intensity proton beams for high intensity targets. In the Basic Energy Sciences and the Department of Defense there is considerable need for intense levels of...
In the past 2 years SuperOx has invested significant resources into developing the next generation 2G-HTS wires for high magnetic field applications and created state-of-the-art production facilities in Japan and Russia, aiming at the fusion, MRI, accelerator magnets and motors markets.
Our current major product is based on the novel YBCO composition fabricated by PLD process on the...
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 the High Field Magnet Laboratory in Nijmegen (HFML). The Toulouse facility is dedicated to the generation of pulsed magnetic fields. It offers...
Recently, a domestic project for the construction of a 4th generation light source, Ochang Advanced Synchrotron for Industry and Science(OASIS), is embarked by the Ministry of Science and ICT in Korea. To increase the performance of the next generation storage ring, Seoul National University in collaboration with Pohang Accelerator Laboratory started a feasibility study on no-insulation(NI)...
Advancements in 2G HTS conductor performance continue to drive the operating limits for a broad range of demanding applications. The design, testing and fabrication technology of 2G HTS (RE)BCO conductors is presented, highlighting the ability of 2G HTS wire to function under a wide range of operating conditions. SuperPower continues to focus on process improvement to achieve high...
Driven by the 1.4 GW generator, the 60TCW magnet was the most powerful controlled waveform system in the world and had always been one of most important magnets to the NHMFL and high-field research community because of its following unique features: (1) quasi-static field up to 60 T with 100 ms flat-top and total pulse-length of 2000 ms, (2) variable magnetic field waveforms such as staircase...
High magnetic fields allow for the stabilization of otherwise inaccessible new quantum states of matter. A scattering technique is imperative for a deep and thorough microscopic understanding of these exotic high field phases in correlated electron systems. We report pulsed magnetic field installation for x-ray scattering experiments, aiming up to 60 T, within an international user consortium...
Design and fabrication of a new Nb3Sn-based superconducting undulator (SCU) are underway at the Advanced Photon Source (APS) of Argonne National Laboratory in collaboration with Fermilab and Lawrence Berkeley National Laboratory. This device will be installed on APS’s storage ring and will deliver a wide range of hard x-rays to APS users. To develop a robust and reliable fabrication process,...
At SuNAM, we set up a new RCE-DR(Reactive Co-Evaporation – Deposition and Reaction) system employing a 100 kW electron-gun for superconducting layer deposition. Using the new system, with higher power and enhanced beam stability, we co-evaporated APC generating materials such as Hf and Zr. We also tried rare earth(RE) elements other than currently used Gd, and mixtures of REs to get enhanced...
In recent years, a huge demand for HTS tape to be used in future commercial fusion reactors has emerged. High requirements on the mechanical properties and the tape performance in high magnetic fields for this market and other high-field magnet applications led to several developments at THEVA that are now transferred to regular production. Major improvements to the engineering critical...
We report on recent progress regarding the practical use and characterisation of fields in the 100-200T range with microsecond-duration at the LNCMI high-field magnet facility. Our Megagauss platform makes use of single-turn coils with 8-15mm diameter that are destroyed in the process, albeit with a close-to-100% chance of survival for scientific equipment in the bore. The setup permits...
The Fermilab Mu2e experiment is currently being built at Fermilab to search for evidence of charged lepton flavor violation through the direct conversion of muons into electrons. The experiment comprises three large superconducting solenoids; the transport solenoid consists of 52 superconducting coils arranged in an s-shaped pattern in order to guide muons from the source to the stopping...
We achieved both high electric conductivity and optimum strength in Cu-0.54Cr-0.046Zr alloy (wt%), and firstly characterized their properties at cryogenic temperature, which was comparable to those of Al60 both at 295K and 77K. Ordered clustering of solute atoms was revealed to be uniformly distributed in solution-treated samples. During deformation, those clusters became the heterogenous...
The critical current density (Jc(θ,B,T)) of ReBa2Cu3Oy¬ (ReBCO) coated conductors is essential knowledge for the safe design of high field superconducting ReBCO magnets. However, though the ReBCO windings in a real coil are oriented such that B is applied typically at a range of 0-18° from the tape plane depending on position in the winding, coated conductors are most often characterized with...
For high magnetic field, the pulsed magnets are normally designed with multiple coils. However, the magnetic field produced by the outer coil starts to drop at the moment when the inner coil starts working due to the electromagnetic coupling. Simulations show that the field drop is as much as 30% if the outer coil is driven by pulsed generator, with the result that the coil has to be designed...
A future accelerator facility to open up a new frontier will require a superconducting magnet with high radiation resistance. A construction plan of a second target staiton of materials and life science experimental facility is proposed as one of the future plans of J-PARC. At the facility, superconducting solenoids are placed just behind the target to maximize the production of secondary...
We have been developing the SCSC cable (or double “SC” cable, standing for Spiral Copper-plated Striated Coated-conductor cable), in which we wind copper-plated striated (multifilament) coated conductors spirally around a round core. In the SCSC cable, its spiral geometry decouples filaments against transverse AC magnetic fields to reduce its AC loss while the plated copper allowing current...
As a part of a conceptual design study for developing more higher magnetic field hybrid magnet, an outsert low temperature superconducting coils which can generate about 14 T magnetic field is being developed at the High Magnetic Field Laboratory of the Chinese Academy of Sciences. The superconducting outsert with a room temperature bore diameter of 1800 mm is composed of Nb3Sn coils and NbTi...
High current superconducting CORC® cable or wire is composed of spiraled HTS REBCO tapes in multiple layers. Multilayered CORC® wires can carry very high currents in background magnetic fields up to 20 T. The cable combines isotropic flexibility and high resilience to electromagnetic and thermal loads. The flexibility of the cable is limited by the critical strain value damaging the REBCO...
The cyclotron CYCIAE-100, the driving accelerator of the Beijing Radioactive Ion-beam Facility (BRIF), was completed successfully to provide up to 52 kW proton beams with energy range from 70 to 100MeV continuously for researches of nuclear physics, material and life science, also for medical isotope production in 2014. Although the design is ‘compact’, the total weight of CYCIAE-100 is still...
In this contribution the magnetic modelling and experimental validation of a superconducting degaussing system for maritime vessels is discussed. Degaussing coils compensate for the distortion in the earths’ magnetic field by the magnetized steel hull of a ship, thus rendering it ‘invisible’ for magnetic field sensors. Whereas typical power requirements with copper coils are of the order of...
A 12 T REBCO solenoid with a 192 mm wide inner bore tapes was designed in the framework of the BOSSE Project, using 12 mm-wide isolated tape as conductor. This 814 mm high coil can be used as a compact 1 MJ – 2 MW inductive energy storage, with an 850 A rated current. One of the objectives was to overcome the present record of mass energy density, held by a NbTi coil (13 kJ/kg), and reach 20...
The linear-motor type high temperature superconducting (HTS) flux pump is a wireless charger which can pump DC current into the second-generation (2G) HTS tapes without the physical contact. In addition ,the flux pump has the smaller volume than the traditional power supply for the same output current. So it is very convenient to charge HTS tapes by utilizing the flux pump which has a compact...
Abstract
A cryogenic permanent-magnet undulator (CPMU) with a period of 18mm and a magnetic length of 2m is being constructed for the Taiwan Photon Source (TPS). The CPMU with a gap of 5.5 mm can generate an effective magnetic field of 1.2 T at 150 K. When the field measurement, the temperature of hall probe will be drop at cryogenic temperature. Therefore, a field strength calibration and...
The flux pumping devices attract a lot of attention for the excitation of superconducting magnets or the compensation of the field decay. A carefully designed linear flux pump is presented in this work, the dimension of which is smaller than a 5 cm cube. The key part of the device is the magnetic circuit which guarantees the optimized flux pumping performance in terms of operation current,...
In order to enhance the quality of measurement results of a Physical Property measurement System using a superconducting magnet, spatially uniform magnetic field is required at the magnet center. However, measured field uniformity is usually worse than that of design result due to manufacturing errors of a magnet system. Therefore, spatial field uniformity compensation is needed to reduce...
The major difficulty of the quench detection of the superconducting magnetic system (SMES) is that the pulsating voltage of the converter is much larger than the local normal-zone voltage of the HTS coils. It is therefore difficult to detect the quench of the superconducting coil (SC) with the voltage measurement method. This paper presents a novel quench detection method without additional...
High temperature superconducting (HTS) magnets have many potential applications, for instance, NMR/MRI, levitation systems, and high field applications. HTS magnets require a constant external current source to operate in CC mode. Flux pumps provide an alternative contact-less charging source that can inject flux into a closed-loop superconducting circuit. The simplicity of the rotating type...
With the Meissner effect and flux pinning, high temperature superconducting (HTS) bulk can levitate with “self-stable” property above a magnetic guideway, integrating levitation and guidance functions in one. Generally, the propulsion function of an HTS maglev transportation is realized by another independent system, which has complicated the entire train system. Lately, according to the...
After completing the 32T all-superconducting user magnet, development of magnets of this class with a noticeably higher field has begun: the NHMFL 40T magnet is the immediate target. The next generation of high temperature superconductor (HTS) high-field user magnets demands the next generation of quench protection systems. Previously, a bank of batteries was employed to power the quench...
No-insulation (NI) winding method has been widely used in the fabrication of superconducting coils due to its excellent thermal stability and mechanical stiffness. In the NI coil, there is a charging delay and heat loss due to leakage current and metal insulated (MI) winding method has been proposed to reduce the charging delay and the heat loss by the leakage current due to the increased...
This paper studied the alternating current (AC) loss of stacked high-temperature superconducting (HTS) tapes based on the finite-element method (FEM). By solving the partial differential equation (PDE) of H formulation, this research analyzed the effects of the frequency, amplitude and phase of the current and magnetic field on the AC loss of the three-layer stacked HTS tapes which works under...
AC loss reduction in HTS coils can help reduce the cryogenic demands and increase the performance of HTS machines. In an HTS coil, most AC loss is generated in the end windings due to the large radial magnetic field in these parts. Therefore, one of the effective methods to reduce AC loss in HTS coils is using ferromagnetic flux diverters to reduce the radial components of the magnetic field...
Double pancake (DP) coils for a SMES coil have been developed using MgB2 Rutherford type superconductor. The DP coils are indirectly cooled in liquid hydrogen in order that the current carrying region such as conductors and leads cannot contact directly with the liquid hydrogen. However the cooling efficiency of the indirect cooling system is less than that of the direct immersed cooling...
Electric machines have been applied to every industrial and transport applications today and are required to realize high-output density.
Superconducting technology is one of the most effective methods for realizing the high-output density motors. The superconducting coils at ultra-low temperature can energize several hundred times higher current density in comparison with copper wires; it...
A 6.5 MVA/25 kV high temperature superconducting (HTS) traction transformer for the Chinese high-speed train was proposed in earlier works aiming to replace the oil-based transformers while achieve higher efficiency, lighter weight, and minimized volume. The high targeted efficiency of the transformer (> 99%) makes AC loss reduction a vital issue. HTS coated conductors generally exhibit...
Rare earth barium copper oxide (REBCO) coated conductors (CC) have high thermal stability and high current density. REBCO CCs are suitable for generating high magnetic fields. It is expected that magnets wound with REBCO CCs are utilized for high magnetic field applications, such as magnetic resonance imaging (MRI), nuclear magnetic resonance (NMR), medical-use accelerators, and compact...
Superconducting materials have a high current-carrying capacity and direct current(DC) lossless characteristics. The linear-motor type flux pump is a wireless DC power source for high-temperature superconducting coils.In the control process of outputting DC current to the superconductor coil.Except for an uncontrollable parameter λ,which length is depended on the length of the teeth and slots...
The INFN-LASA laboratory (Milano, Italy) is involved in the High-Luminosity LHC program for the design, construction, and test of 54 superconducting high-order corrector magnets. One of the challenging project stages was the transition from the construction of prototype magnets to the series production, awarded to industries with the demanding requirement of maintaining high-quality production...
Quench protection is one of the key issues for superconducting magnets with high energy storage, especially for those wound with superconducting cables, which have low thermal conductivity between each turns. Thermal quench-back induced by a co-wound heater wire is an available quench protection scheme for the magnets wound with 6+1 type cables (6 superconducting wires wound with 1 heater...
This paper presents the results about analysis and experiment on the electrical and thermal characteristics of metal insulation (MI) REBCO racetrack coil wound with stainless steel (SS) tape under rotating magnetic field. The field windings of synchronous rotating machine can be occasionally operated under time-varying magnetic field due to the unsynchronized armature windings during...
The ITER Central Solenoid (CS) will be realized by assembling a stack of six modules. Each module is a solenoid consisting of 40 pancakes wound with a Nb3Sn Cable in Conduit Conductor (CICC). The tests of the second module (CSM#2) are ongoing at the General Atomics (GA) facility in San Diego (US). During the test campaign, the CS Module is submitted to dumps of the transport current from...
A prototype racetrack high temperature superconducting (HTS) magnet used for high-speed superconducting maglev has been in progress at Institute of Electrical Engineering, Chinese Academy of Sciences. The dynamic thermal and mechanical characteristics of the racetrack HTS coil is affected by multiple factors while it is accelerating, which has an effect on the operating margin inversely. To...
During 2020, the SULTAN test facility was upgraded to host Quench Experiments on HTS conductors. In the frame of the EUROfusion program, few cables based on the Swiss Plasma Center (SPC) Twisted Stack-Tapes design have been manufactured and successfully tested. Each conductor addresses a specific design parameter. For the first time, it was possible to observe the quench evolution and...
REBCO coated conductors are expected to apply high field superconducting magnets since they have high critical currents and excellent mechanical properties. It is well known that REBCO coated conductors have angular dependence and strain dependence of the critical current in magnetic field. However, there are few experimental results of angular dependence of critical current under strains....
Authors: Keyang Wang, V A Anvar, Yuanwen Gao, Danko van der Laan, Jeremy Weiss, Arend Nijhuis
The Conductor on Round Core (CORC®) cable or wire comprises several layers of helically wound HTS tapes on a round core with the winding direction reversed in each successive layer. This configuration can significantly reduce the AC loss while improving the bending flexibility. However, compared...
A floating offshore wind power generation has been investigated to reduce the greenhouse gas emissions in Japan. When the floating offshore wind farm transmits AC electric power to the commercial power system on the land using a copper cable, it is necessary to increase the voltage by an offshore transformer facility in order to reduce the transmission loss of the copper cable. However, it is...
INTRODUCTION
Recently, magnetic levitation techniques have been developed for various fields such as magnetically levitated vehicles and energy storage flywheels. Thus, there are many reports about levitation techniques using high critical temperature (Tc) superconducting magnetic bearings (SMBs) composed of superconducting (SC) bulk and permanent magnet (PM). However, there are not so...
High-temperature superconductors have significant potential for application in systems based on magnetic levitation: levitation bearings, magnetically suspended transport, flywheel energy storage devices, motors and generators. Bulk REBCO (where RE stands for rare earth elements) is currently a widely used material. However, the widespread use of coated conductors tapes (CC-tapes) allows to...
Use of 2G HTS superconductors in magnet applications allows creating compact magnets with large magnetic fields due to many times higher current density of superconductors in comparison with traditional metal wires. At the same time, 2G HTS tapes make the design of magnet special and require choosing 2G HTS tape parameters suitable to each magnet design. The unique properties of 2G HTS tapes...
A lightweight superconducting gantry with large momentum acceptance is under development at Huazhong University of Science and Technology (HUST), which is based on strong focusing and local achromatic technology. The essential component of this superconducting gantry is the curved alternating gradient canted-cosine-theta (AG-CCT) magnet. This paper introduces the study on coil error analysis...
A combined method was used for mapping the fields in the pulsed bending magnets of the Booster-Nuclotron transfer line of the NICA complex. In the measurements, an array of “point” search coils was used together with Hall sensors. Signals from coils were processed by digital integrators, and a specially designed fast precision ADC was used in Hall measurements. The paper presents the results...
In many industrial applications, there has been a growing need for electrical motors having high performance such as high power density and high efficiency. An electrical motor with high temperature superconducting (HTS) coils allows to offer those advantages due to the very high current density compared with conventional superconducting motors. HTS motors can be divided into an inner rotor...
Permanent magnet guideway (PMG) has commonly been used for an HTS maglev system so far. In some previous studies, electromagnetic guideway (EMG) was proved to have some advantages in a practical HTS maglev construction.
EMGs with different geometries produce different magnetic field distributions and have different performance characteristics in a HTS maglev system. In this study, comparative...
The concept of an electric aircraft and ship implies the development of an entirely new electric propulsion system. Among the key technologies of these systems, electric motors and generators are required for high performances such as high efficiency and high specific power. In this paper, a study on the electromagnetic design of the MW class superconducting (SC) machine according to...
A conceptual design study of superconducting toroidal field (TF) magnet for a steady-state Korean fusion demonstration reactor (K-DEMO) was done in 2015. Through some minor design modifications of the K-DEMO TF magnet, the maximum toroidal field strength of the K-DEMO is expected to be about 16 T. In order to test a Cable-In-Conduit Conductor (CICC) of the K-DEMO TF magnet, a conductor test...
Sirius is a 4th generation light source with a sub-nm.rad horizontal emittance currently under commissioning in Brazil. The Sirius beamlines will mainly use insertion devices as the source of synchrotron light, and some of the beamlines will use the currently installed central dipole magnets (permanent magnets) of 3.2 T. However, there is a demand for a high-energy x-ray tomography beamline...
Abstract: A closed-loop high temperature superconducting (HTS) magnet with thermal switch, wound by REBCO wire, is proposed, which can be magnetized by flux pump and operated in persistent current mode. In this paper, the structure, fabrication and principle of the magnet is explained. Because the magnet has the structure of thermal switch, it can be excited to saturation efficiently....
The new HEL (Hollow Electron Lens) units are part of the upgrade baseline of the High-Luminosity LHC accelerator (HL-LHC) will be installed in the machine ring at point P4 on each counter-rotating LHC proton beamline during a long shutdown in 2025-2027 at CERN. The main goal is to achieve active control of the proton beam halo as a robust solution of risk mitigation to improve the collimation...
The high-temperature superconductor REBa2Cu3Oy (REBCO) is expected to be applied to fusion magnets because of its high critical current density at 20 K [1]. Various kinds of REBCO conductors with a large current capacity have been developed for the fusion magnets by stacking the REBCO tapes such as FAIR conductor [1]. A drawback of REBCO conductors is that the buffer layer prevents current...
Racetrack model coils (RMC) have been built at CERN during the past decade, as a R&D tool to qualify conductors and technologies developed for high field superconducting magnets. Racetrack model coils, assembled in a dipole magnet configuration, proved to be an efficient instrument reducing cost and feed-back time while developing new magnets. In a similar way as for the HL-LHC project, CERN...
With 3 GeV electron beam energy for the National Synchrotron Light Source II (NSLS-II) ring, only superconducting wiggler (SCW) producing greater than 4T peak field can cover photon energy range of 20keV and 200keV with sufficient number of photons. The High energy Engineering X-ray (HEX) Diffraction beamline, which is primarily funded by the New York State Energy Research and Development...
The muon g-2/EDM experiment, which aims at the ultra-precise measurement of muon anomalous magnetic moment (g-2) and electric dipole moment (EDM), is now under planning at J-PARC. For muon g-2, there is a discrepancy of more than 3-σ between the theoretical calculation in the Standard Model and the experimental results in the preceding experiment. Therefore, muon g-2 is one of the promising...
Two out of six Poloidal Field Coils (PFC) are already delivered to the ITER Organization. The PFC are built winding, impregnating and vertically stacking double pancakes (DPs) of NbTi Cable-in-Conduit conductors into a Winding Pack (WP). Later, the Winding Pack (WP) is impregnated for ground insulation and clamping devices are installed for structural support and interface with the rest of the...
In April 2021, four Toroidal Field Coil (TFC) built by European industries are already delivered to the ITER Organization. The TFC are composed mainly by a superconducting Winding Pack (WP), and the enclosing Coil Cases (TFCC).
One of the main parameters characterizing the TFCs is the Current Centre Line, defined as the barycentre of the WP conductors. The CCL has been initially calculated...
With the increase of the permeability of renewable energy, the equivalent inertia and damping of the power system gradually decrease, which makes the power system stability problem more and more prominent. By emulating the electromechanical transient characteristics of synchronous generators, the virtual synchronous generator (VSG) technology enables the renewable power generator to have the...
Research and development of large-current High-Temperature Superconducting (HTS) conductors toward the application to magnets of experimental nuclear fusion devices are in progress at NIFS. As a candidate, the FAIR conductor [1] has been developed. Using a number of HTS REBCO tapes, we have been optimizing the manufacturing process of the conductor by repeating current-transport tests in...
If filaments in a multifilament coated conductor are insulated electrically one another, the current carried by each filament could be restricted by its lowest local critical current along its length. The critical current of such a multifilament coated conductor could be the sum of the lowest local critical currents of all filaments. Considering a longitudinal variation in local critical...
REBCO with its high-strength substrate is the preferred superconductor for high-field applications and is the choice for the NHMFL’s 40 T all-superconducting magnet. Many electromechanical characterizations of this conductor have been performed in its longitudinal direction which is its primary load path. Little has been reported on structural limits in its transverse, narrow edge, direction...
In recent year, there has been remarkable progress in the use of high-field rare-earth barium copper oxide (REBCO) coils in NMR, MRI, and accelerator applications. No-insulation (NI) winding techniques are adopted to achieve high thermal stability and high current density. Thus, each winding in a non-impregnated NI REBCO coil can deform separately and move freely because of the thermal strain...
No-insulation (NI) high-Tc superconducting (HTS) coils process much higher thermal and electrical stability than the conventional insulated coils. In some rotating machines and Maglev trains, HTS coils carry persistent current and serve as the permanent magnets. For these applications, the main issue is that the demagnetization of HTS coils caused by the local external alternating fields. This...
Recently, as interest in high-efficiency motors has increased, motors of various structures have been developed. In particular, the axial flux motor has a relatively low leakage flux, so the power density, output torque, and efficiency are high. High-temperature superconducting (HTS) coils have a higher magnetic flux density than permanent magnets. Therefore, by applying HTS coil to the...
In this paper, a laboratory electromagnet utilizing high temperature superconducting (HTS) coils is designed and analyzed. The laboratory electromagnet is applied to excitate high magnetic fields compared with the conventional laboratory electromagnet with copper coils. The proposed electromagnet was composed of iron-core, HTS coils, and cryostat for the HTS coils. The components are designed...
A proton therapy equipment named SC200 is developing in the Institute of Plasma Physics Chinese Academy of Sciences (IPP, CAS) and Heifei CAS Ion Medical and Technical Devices company. In order to develop a light weight gantry for proton therapy, the Canted Cosine theta (CCT) superconducting magnet technology was considered to apply in the superconducting gantry development. The designs of two...
CERN is currently investigating the feasibility of a future collider - the Future Circular Collider (FCC)- as a potential successor of the Large Hardon Collider (LHC), providing scientists in the field of high energy physics with a powerful discovery tool. A 100 km tunnel hosting a circular electron–positron collider as a first stage towards a 100 TeV proton–proton collider would probe new...
In the magnetic Czochralski crystal growth (MCZ) process, a Lorentz force that influences the flow and tends to reduce the amplitude of the melt fluctuations by applying a magnetic field outside the furnace body. It is a main method to suppress the uneven distribution of impurities and reduce the density of crystal defects. The strong magnetic field provided by superconducting magnet is a...
A lightweight superconducting (SC) gantry with large momentum acceptance is under development at Huazhong University of Science and Technology (HUST). Three types of combined-function quadrupole-sextupole (QS) magnets are used to suppress the chromatic dispersion for the large momentum acceptance. Moreover, the size and weight of the gantry can be further reduced. This paper introduces the...
To study the properties of the Higgs, scientists from the Institute of High Energy Physics have proposed to build the Circle Electron Positron Collider (CEPC) and published a conceptual design report in 2018. In order to improve the luminosity of the CEPC, the final focus system in the interaction region is continuously upgraded. According to the latest physical requirements of superconducting...
The wireless power transfer (WPT) using magnetic resonance coupling method has been known to have the advantage of being able to transfer power across large air gap with considerably high efficiency. As well as, as such a method can eliminate the physical contact loss in the system, it provides an ideal solution for the problem of contact losses in the power applications. From these reasons,...
Since the late 2000s, research on electric turbo engine propulsion aircraft is being actively conducted in the aircraft industry to reduce environmental pollution and increase energy use efficiency. The electric propulsion aircraft will be equipped with a large-capacity, high-power density electric motor and generator with superconducting technology. In order to develop superconducting...
The composite method is an effective way to obtain superconductors with better performance. Through the combination of the first and second generation high temperature superconductors, the stability of superconductors can be improved, the engineering current density can be increased, and the AC loss of superconductors can be reduced. In this paper, a HTS transformer with first and second...
Proton therapy (PT) is a precise and efficient radiotherapy method in modern medical treatment, which can be focused on the lesion location to kill the tumor cells with little affection on the normal tissues and thus largely reduce the potential side effects. However, the proton therapy instrument is usually very huge with a large occupation in the space. In order to reduce the instrument...
Rotating coil magnetic field measurement system is an essential component to achieve the multipole harmonic fields measurement in accelerator quadruple magnets. The fundamental requirement for the coils are accuracy, easy fabrication and low-cost, so that the coil parameters can be customized to the magnet requiring test. This paper introduces the application of PCB technique on rotating...
Abstract—Superconducting magnetic energy storage system (SMES) has the advantages of fast response, four quadrant adjustable active and reactive power. It can improve the stability of power system, improve power quality, be used as distributed power system and energy management in power system. The research and development of large capacity energy storage magnet is an important...
The High Luminosity LHC requires dipole orbit correctors grouped in double aperture magnet assemblies. They provide a field of 3.1 T at 100 A in an aperture of 70 mm. The current standard design is a classical cosine-theta layout made with ribbon cable. However, the electric insulation of the ribbon cable is however not radiation-resistant enough to withstand the radiation load expected in the...
Design of a beam transport line for a newly developed three-dimensional spiral injection scheme is discussed. This transport line is unique and one of key equipment for a new experiment at J-PARC, which measures a muon anomalous magnetic moment (g-2) and electric dipole moment (EDM) to explore a new physics beyond the standard model. Very precise measurement on spin precession angular momentum...
We present the design of a four-layer, Canted Cosine Theta (CCT) Nb3Sn dipole magnet as part of the general R&D program for high field superconducting magnets supported by the US Magnet Development Program (US-MDP). Future testing with HTS inserts in a hybrid configuration motivates the design’s large clear aperture of 120 mm and target operating dipole field of 12 T. First, we show results...
Abstract:
High-temperature superconducting (HTS) magnet is a promising candidate for transportation systems and power systems, such as ultra-high field magnet, electrodynamic suspension (EDS) train, magnetic resonance imaging (MRI), due to its large current-carrying capacity and low power loss. The critical current of the HTS magnet depending on magnetic flux density is an essential...
We propose the electric propulsion system which are composed of 10 MW superconducting generators, superconducting transformers, superconducting cables, and 2 MW superconducting motors. The design study of 2 MW fully superconducting motors with a rated voltage of 1 kV is being conducted. On the other hand, the 10 MW fully superconducting synchronous generators were designed so as to operate at...
Accelerator magnet test facilities frequently need to measure different magnets on differently equipped test stands and with different instrumentation. Designing a modular and highly reusable system that combines flexibility built-in at the architectural level as well as on the component level addresses this need. Specification of the backbone of the system- the interfaces and dataflow for...
Protecting a high temperature superconducting (HTS) magnet from a quench event is a challenging task, especially in the case of accelerator magnets where current density is usually very high. Because of the slow normal zone propagation velocity, the long reliable quench detection method by coil voltage may not be timely for HTS anymore, leaving HTS magnets under danger of overheating. Many new...
In order to meet the requirements of the large HTS solenoid detector magnet for Circular Electron Positron Collider (CEPC), a new high temperature superconducting cable, Aluminum stabilized Stack ReBCO Tape Cable (ASTC) has been proposed and developed. The HTS conductor is one of the promising options for the large solenoid applications. In this study, a 20 layers ASTC sample has been...
AC loss is a major heat load in the fast-pulsed, superconducting ITER coils, and thus a design driver for the cryo-system and superconductor. Given the importance of AC loss, extensive AC loss characterization of the components of the ITER coils, from the superconducting strands, cables and insert-coils to the completed coils, were conducted over the past years.
Following factory cold...
Space charge compensation technology using multiple multipolar magnetic field components has been applied to high intensity beam transport. In order to realize this compensation technology in a limited space, we devised a compact size permanent hybrid multi-pole magnet. This magnet can produce two or more adjustable multi-pole components at the same location. In this presentation, we will...
We proposed the novel separation method, which is the combination of magnetic separation and selection tube, aiming at more precise and easier separation for the paramagnetic substances than the conventional High Gradient Magnetic Separation (HGMS). In order to control and separate the paramagnetic substances with magnetic force, the magnetic field of higher than 5T and high gradient magnetic...
High–temperature superconductors (HTSs) still hold some unignorable issues, such as AC losses and its poor robustness against normal transition. For HTS tapes, dividing superconducting layer into filaments by striation shows remarkable effects on reducing AC losses. However, it could deteriorate robustness due to blocking a current sharing among filaments. Thus, plating copper on the entire...
The J-PARC muon g-2/EDM experiment aims to perform ultra-precise measurements of anomalous magnetic moments (g-2) and electric dipole moments (EDM) from the spin precession of muons in a precise magnetic field, and to explore new physics beyond the Standard Model. On experimental requirements, the beam must be stored in a compact storage orbit with a diameter of 66 cm, which is about 1/20th...
Ceramic powders A1-xSrxTiO3 (where x = 0.02, and A=Ba2+, Pr3+, Sm3+, Eu3+, and Er3+) were synthesized by solid-state reaction method and sintered at up to 1400 °C. The phase formation, elemental composition, and microstructure of the sintered samples were investigated by TGA, XRD, EDX and SEM techniques, respectively. The results of the partial substitution of Ba ions by other rare earth ions...
The high-field magnets experience the large amount of mechanical stress as a result of Lorentz forces. During the magnetization of the coil, strong Lorentz forces give rise to hoop stress, which can cause mechanical failure, resulting in the degradation of the coil performance. A recent study led to the discovery that scratching the GdBCO-coated conductor (CC) tapes ameliorated the degradation...
We aim to develop a persistent-mode 1.3 GHz (30.5 T) LTS/HTS NMR magnet. For protecting the layer-wound REBCO innermost coil from quench, we have proposed the intra-Layer No-Insulation (LNI) method. This winding technique employs single-sided insulated copper sheets as inter-layer materials to provide the no-insulation state within each layer. For quench protection, the most influential...
REBCO tapes have good critical current characteristics under high magnetic fields. Their application to superconducting magnets generating above 25 T is under active study. However, performance inhomogeneity along their length can cause damaging hotspots. Adapted winding technologies are needed to mitigate this phenomenon. One of such winding techniques is the two-tape bundle co-winding...
A Cos-theta type fast cycling dipole model for synchrotron is being developed at IMP. The magnetic field of the dipole is 6 T with maximum ramp rate is 1 T/s. The coil inner diameter is 80 mm and two-layer coils are used to produce accelerator field quality in two third of coil aperture. Rutherford cable with 316L stainless steel core is used to reduce the inter-strand couple loss. Low loss...
A project to develop a compact heavy-ion therapy device has been initiated at the National Institutes for Quantum and Radiological Science and Technology. The therapy device uses a 430-MeV/u synchrotron with superconducting bending magnets as a main accelerator. In order to reach the required output of the heavy-ion beam, the bending magnets have been designed to be operated alternately from...
In heavy particle radiotherapy, a rotating gantry enables charged particles to be delivered to a tumor with great accuracy. Therefore, cancer therapy that minimizes unnecessary damage to a patient can be realized by using the rotating gantry. The world’s first rotating gantry composed of superconducting magnets was developed in Japan. Using superconducting magnets instead of conventional...
We have been developing a no-insulation (NI) REBCO coil system for medical accelerators and high-field magnetic resonance imaging (MRI). There are increasing attempts to apply NI winding technology to achieve both high current density and high thermal stabilization of REBCO coils. However, REBCO coated conductor has a tape shape, and when a magnetic field is applied vertically to the tape...
REBCO coated conductors have a high critical current density in a high magnetic field at low temperature. Therefore, the research and development of REBCO coated conductors have proceeded for high magnetic field applications. A critical current of REBCO coated conductor shows field angular dependence and strain dependence. Especially, the mechanism of the strain effect for REBCO coated...
Applications for coated conductors, such as fusion magnets, power transmission and generator windings, require high current-carrying capacity. This requirement can be fulfilled by various cable concepts using commercial lengths of REBCO coated conductors with high current-carrying properties, such as Rutherford cables. In the past few years, our group has successfully developed Quasi-isotropic...
Superconducting magnetic energy storage (SMES) has the advantages of high efficiency, longevity, and excellent instantaneous response with high power. However, it has the disadvantage that its storage density is extremely small compared to other power storage devices. The no-insulation coil (hereinafter referred to as "NI coil") is expected to be a winding method that can achieve both high...
The ITER Central Solenoid (CS) consists of a stack of six independent coil packs called modules. It features a total height of 18 m and a diameter of over 4 m. The modules are in an advanced stage of fabrication by the US ITER Project Office (USIPO) and its subcontractor General Atomics (GA). A qualification module mock-up at one to one scale but of reduced height was wound and Vacuum Pressure...
The authors’ group is investigating a quench protection method for HTS coils that use Cu tape co-wound with HTS tape. In this method, the voltage $V_s$ across the resistive zone in the HTS coil is monitored by measuring the voltage difference between the HTS coil and the co-wound Cu tape coil in normal operation. When $V_s$ exceeds the quench detection voltage, the HTS coil is disconnected...
The no-insulation (NI) winding technique provides high stability of HTS pancake coils and a high magnetic field NI HTS magnet was developed. On the other hand, the balance between the turn-to-turn contact resistance and the coil inductance is an important factor to characterize the thermal stability and charging delay of NI HTS coils. So, it is very important to accurately measure and evaluate...
Large-scale high temperature superconducting (HTS) wind power generators suffer from the high electromagnetic force and high torque due to their high current density and low rotational speed. Therefore, to maintain the mechanical strength of the HTS coil, the torque and Lorentz force of the HTS wind power generator must be carefully investigated. This paper deals with the experimental test...
High Temperature Superconductor (HTS) based magnets are potential candidate for the future fusion reactors and electrical industries due to its compact size and operational economy. A SS laminated BSCCO-2223 HTS tape based and double pancake wound compact solenoid coil with an inter-double pancake joint of bore diameter 50 mm with 24 nos. of turns has been fabricated and tested at LN2...
A new solution for cost effective, high average power (2 GeV, 6 MW) proton accelerator has been proposed and studied since 2013. The energy limit of isochronous accelerator has been successfully increased from 1GeV to 2GeV. In 2019, China Institute of Atomic Energy (CIAE) started the design of a 2 GeV FFAG accelerator and launched the preliminary study on the design of a high-temperature...
Three racetrack type double-pancake coils were wound and assembled in a certain sequence to form a module. To improve the anisotropism between the straight sections and circular sections, the bobbin was designed and some clamping fixtures were added on both sides and on the straight sections. By investigating the viscosity and torque of rotor, the optimum range of temperature for impregnating...
Fusion for Energy (F4E), the European Domestic Agency for the International Thermonuclear Experimental Reactor (ITER), is responsible for the supply of 5 out of the 6 Poloidal Field (PF) Coils: PF2-PF6. While the 9 meter diameter PF6 was manufactured by the Institute of Plasma Physics Chinese Academy of Sciences (ASIPP) and tested in the cold test facility at Cadarache under a collaboration...
Feasibility study of ITER In-vessel coils bracket manufacture and integration had been developed in Institute of Plasma Physics, Chinese Academy of Sciences. The ITER In-Vessel Coil system is comprised of Edge-Localized Mode (ELM) and Vertical Stabilization (VS) coils. The ELM coils are used to mitigate the Edge Localized Modes and the VS coils are used to provide Vertical Stabilization of the...
Canted-Cosine-theta (CCT) magnet is an excellent dipole magnet structure design for developing high-field accelerator magnets, because of its modular construction and the prevention of the Lorentz-force-induced conductor stress accumulations. Although REBCO tapes can maintain a relatively higher engineering current density than other superconducting conductors in the high field environment, it...
The U.S. High-Luminosity LHC Accelerator Upgrade Project (HL-LHC AUP) is developing MQXFA magnets, a series of 4.5 m long 150 mm aperture high-field Nb$_3$Sn quadrupole magnet for the Hi-Luminosity LHC upgrade at CERN. Five Pre-Series magnets, MQXFA03 through MQXFA07, have been developed. During the magnet assembly stage, we perform magnetic measurements of the coil packs and magnets to track...
Two types of nested orbit combined correctors are necessary for LHC upgrade, so called MCBXFA and MCBXFB. They shared the same cross section, but feature different lengths, 2.5 and 1.5 m, respectively. The power tests performed on two prototypes showed an excellent performance when individually powered, but the training to reach nominal torque in combined operation was very long. Moreover,...
AC losses in stacked bundle conductors exposed to external magnetic fields are numerically evaluated by means of a two-dimensional finite element method formulated using a self-magnetic field due to currents induced in an analysis region. The bundle conductor is composed of two pieces of rare-earth-based coated conductors without electrical insulation to improve the thermal stability. In the...
Bi:2212 superconducting cables are being considered for use in high field magnets such as those in the next generation of particle accelerators. However, a comprehensive understanding of their behavior is necessary before full-scale magnets can be constructed. The magnetization and flux creep in the superconductor can lead to significant field errors which need to be compensated. To study...
For mechanical reinforcement against the huge Lorentz forces in high magnetic fields, epoxy resins are commonly used to impregnate the high temperature superconducting (HTS) coils. However, performance degradation of the epoxy impregnated HTS coils is inevitable due to different thermal expansion coefficients between the epoxy resin and the HTS tape. The ice impregnation technique of pulsed...
The flux pump technology is bale to output ultra high current for the High temperature superconducting (HTS) magnets without the copper current leads. This can make the HTS magnets system more compact and save more energy. Currently, the flux pump technology is moving forwards to high current level up to 1-2 kA. But there are still mane components to be optimized and studied, and the HTS...
This paper studies the principle of direct current and DC bias voltage induced by superconducting tape in a linear magnetic flux pump system. The external magnetic field is a comprehensive magnetic field composed of a bias magnetic field and a traveling wave magnetic field. An experimental platform for linear magnetic flux pumps was built. Using a combination of simulation and experiment, the...
As the experimental ITER fusion reactor faces its final construction phase, design activities of the next reactor DEMO that will supply net electrical energy to the grid are being conducted in Europe. DEMO will be significantly larger than ITER, and its magnet system will be key to confine the plasma and control its shape. In particular, the Toroidal Field (TF) Coils are necessary to generate...
Recent advances in the fabrication of high-temperature superconducting (HTS) coils allow the design of superconducting accelerator magnets working in a persistent current mode. There are many various rather low field magnets in the particle accelerators which operated in the DC current mode. At Fermilab was designed, fabricated, and tested the HTS dipole magnet model having 20 mm air gap and...
Abstract — This work investigates the effect of rotor eccentricity and current harmonics on the performance of high-speed permanent magnet (PM) generators (HSPMG) with multi-physical analysis. First, the effect of rotor eccentricity in the no-load and load conditions on the distributions of magnetic flux density and electromagnetic force in the generator is studied and the allowed...
In this article, we proposed a method of using multiple linear flux pumps to charge an HTS magnet and set up an experimental system. The system mainly includes three linear-motor flux pumps and five HTS double pancake coils, of which the five coils form an HTS magnet. Each linear-motor flux pump adopts an independent inverter and a DC power supply for cluster control. In order to obtain the...
In conventional transport systems using wheels and belts, there are friction that generates wear of mechanical parts and consequently reduces the whole system efficiency and this a problem, especially when using it in special environments such as clean room. As a way to solve this problem, a magnetic levitation system was developed using magnetic levitation as main technology. Called Hybrid...
Nb3Sn conductors are prone to quench due to deposition of heat energy from disturbances such as flux jumps and cracking of nearby epoxy, which push the conductor into the normal state. In Nb3Sn magnets, this manifests as training, wherein the magnet can reach a progressively higher current after a succession of quenches. By incorporating substances with a higher heat capacity at cryogenic...
Sigmaphi participated to QUACO PCP whose objective was to propose an innovative solution for MQYY superconducting quadrupole magnets of HL-LHC Insertion Region. QUACO project was divided in three phases: a feasibility study, a detailed study including mock-ups and the manufacturing of a MQYY first-of-a-kind based on an innovative concept.
The innovation proposed by Sigmaphi concerns the...
For high field accelerator magnets, it is more attractive to wind the coils with a compact high current-carrying capacity cable, which is composed of tens or even hundreds of superconductors. In the last decades, various ReBCO cable conceptions have been proposed, but only a few cables, such as Roebel cable, can achieve a current density as high as single tapes. However, the high performance...
LN2/CF4 mixture would be an effective coolant and insulating medium of high-temperature superconducting (HTS) magnets and power devices, which could provide a cryogenic environment in the temperature range of 50 to 100 K and serve as a liquid dielectric. In this paper, recent progress concerning the LN2/CF4-cooled HTS power devices including superconducting fault current limiter (SFCL) and...
In this study, the quench initiation and propagation characteristics of REBCO coil, which was electrically and thermally insulated by a vanadium III oxide (V2O3), were investigated under internal heater activation. When the quench occurs in REBCO coil, V2O3 insulator can enhance the thermal stability of REBCO coil due to its automatically and remarkably switched from high to low turn-to-turn...
The REBCO coil, which was electrically insulated using a metal-insulator transition (MIT) material between turn-to-turn contact layers, can achieve high stability in the transient operation as well as fast response of magnetic field in the normal operation due to its automatically switched electrical resistivity of MIT material according to the temperature changes. Among of MIT materials, A...
Currently, the development of superconducting magnetic energy storage devices (SMES) based on the cables from high-temperature superconducting tapes of the second generation are carried out. Such SMES will be used, for example, in the NIKA project to power the pulsed magnets of Booster and Nuclotron accelerators. Similar cables may be used in accelerating magnets as well. The number of working...
During the NHMFL 32 T magnet project, a program to develop a reliable method for making soldered lap joints between REBCO tape conductors was initiated. Several combinations of solder, flux and process were tried and then tested in liquid nitrogen. A standard process was adopted from the findings of that study. For each unique REBCO conductor piece procured for the 32 T project, a lap solder...
We have been studying a magnetic levitation system using a magnetic shielding effect of HTS bulks. The analysis method is numerical simulation utilizing the 2D and 3D finite element method software, COMSOL Multiphysics. This system consists of three items which are an iron rail, the HTS bulks, and the magnet. In the former work using a permanent magnet, the peak levitation force was smaller...
As is well known all types of superconductors are affected by AC losses.
Those losses occur when a time varying current flows in a superconductor or when it’s subjected to a variable magnetic field.
The main effect of these losses on the conductor is temperature rise due to the energy dissipation within the superconductor. Many methods were previously studied in order to reduce the magnitude...
The last bending section of a proton therapy beam line is mounted on a rotating gantry to target the cancerous cells of the patients from all possible angles. Such capability can increase the effectiveness of cancer treatment as the tumors would receive the appropriate amount of radiation dose with a minimum impact on the surrounding healthy tissue. Superconducting magnets with their high...
LQXFA/B production series cryogenic assemblies are being built for the LHC upgrade by the HL-LHC Accelerator Upgrade Project (AUP). These contain a pair of MQXFA quadrupole magnets combined as a cold mass installed within a vacuum vessel, and are to be installed in the IR regions of the LHC. The LQXFA/B are being tested at 1.9 K to assess alignment and magnetic performance at Fermilab’s...
A beam separation dipole of the High-Luminosity LHC, known as MBXF, is a 7-m NbTi magnet, which is designed to generate 35 Tm at the operating condition of 1.9 K. The magnet has a collared yoke structure with a 150-mm-aperture single-layer coil. The dipole field is 5.6 T at nominal operating current while a b3 integral is required to be within 2.9 units. The target pre-load is set to 115 MPa...
The Large Hadron Collider (LHC) upgrade, called High Luminosity LHC (HL-LHC) is planned for the next decade. A set of twin aperture beam orbit correctors positioned on the approaches to the ATLAS & CMS experiments will be developed. Tow institutes IHEP (Institute of High Energy Physics), IMP (Institute of Modern Physics), and one company in China will work on the magnet R&D and series...
High temperature superconductor (HTS) coil has superior current-carrying ability, and can trap higher magnetic fields, thus shows a promising application on machines with super high power density. Winding coils with bare tapes without any insulation, which is called no-insulation (NI) coil, can significantly enhance the thermal stability and reliability of HTS coils. However, in many...
The paper presents a description of the magnets for transfer line to transport ions from the Booster to the Nuclotron at the NICA project.
The transfer line has a complex three-dimensional structure because of the Booster and the Nuclotron are located in two levels. To realize complicated geometry of the transfer line necessary to reduce the magnets weight. Due to this they are made pulsed....
The ITER PF system consists of 6 ring coils and it provides magnetic field for plasma shaping and position control together with the Central Solenoid (CS) coils. It needs to operate in a fast pulse mode, leading to induced voltages of up to 14 kV on the coil terminals during operation. The cable-in-conduit conductors (CICC) with Niobium-Titanium (NbTi) superconducting material are used in the...
High Temperature Superconductor (HTS) are one of the most promising applications of HTSs as they offer a means of charging magnetic loads without the need for physical current leads. Flux pumps have been generally built using Low Temperature Superconductors (LTSs), although their implementation using HTSs has been the subject of recent research interest owing to their lower cryogenic...
In order to examine the applicability of superconducting technology to fields of industrial applications such as linear conveyor, transfer, and transport systems, we investigated AC loss characteristics of HTS sample coils under conditions assumed for use in power electronics devices. Since inverters are used in the drive circuit of power electronics devices in a linear transfer system and so...
In the case of a REBCO superconducting coil, the coated conductors endure both tensile and bending strain. Therefore, the mechanical behavior of REBCO coated conductors and its effect on the critical current under combined tensile-bending deformation should be revealed. In this study a mixed-dimensional laminated composite finite element model (FEM) for REBCO conductor is developed for stress...
In the quest of higher field accelerator superconducting magnets, essential parts of their design are the so called yokes, which are traditionally made of low – carbon magnetic steel. In currently used magnets, they are typically found in the form of fine – blanked laminations, or machined from laminated heavy plates. The material’s choice is made based on a compromise between the high...
The future of the particle accelerators points to a new CERN’s circular collider with an order of magnitude increase in the center-of-mass energy compared to the Large Hadron Collider (LHC). To achieve this increase from 14 TeV to 100 TeV a 100 km tunnel will be required to host the collider. This particle accelerators requires a new generation of double aperture superconducting magnets,...
To guarantee the required performances stringent dimensional requirements have been defined for the ITER TF coils.
The assembly of the European magnets from its components, the Winding Pack (WP) and the stainless steel Coil Cases (CC), is currently under responsibility of SIMIC SpA in the framework of a Fusion For Energy contract.
The process has been divided in the following stages:...
The superconducting electrical machines are going to be widely used in many modern transport applications in near future. In fact, their great features such as high efficiency, high torque density, high power density, and lighter weight make them an excellent fit for electric aircraft and marine applications. The fully superconducting machines built with superconducting magnets requires a...
REBCO wires have high thermal stability and high current density, therefore, it is expected to be applied to high magnetic field magnet for NMR, MRI, and accelerators. On the other hand, there is the problem such as mechanically deteriorations and damages of REBCO coils. Because REBCO wires are tape shape, when charging and discharging, screening currents are induced to circulate in the...
Targeted alpha-particle therapy is a cancer treatment method using alpha-emitting radioisotope (RI), and is expected as a treatment method for progressive cancer. We are conducting research toward the development of a High-temperature-superconducting Skeleton Cyclotron (HTS-SC), which is an ultra-compact and high-intensity accelerator capable of stably producing the alpha-emitting...
Due to the normal zone propagation velocity (NZPV) of a high temperature superconductor (HTS) being about 100-1000 times slower than that of a low-temperature superconductor (LTS), the quench detection is a difficult challenge for HTS structures so far. To propose more effective quench detecting methods and criterion, it is necessary to reveal the mechanism and multi-field coupling behavior...
High-temperature superconducting (HTS) magnets have been widely used in the fields of electricity, transportation, medicine, and scientific experiment. However, HTS magnets generally suffer from the thermal stress and electromagnetic stress during manufacture and operation, deteriorating its mechanical properties as well as restricting its further development. This study is aimed at improving...
Stress managed magnet designs are being developed to limit the strain and stresses applied to the conductor during powering. The canted cos $\theta$ (CCT) design is one of the proposed solutions. In this design, the conductor is wound around a mandrel: the impregnation process creates a bonding between the two, that can fail when the magnet is powered. The energy releases consequent to the...
2G high temperature superconducting (HTS) coil working in persistent current mode (PCM) has shown a superior potential in linear motor applications. While due to the external magnetic field, specifically, the harmonic field component generated by the ground coils, the HTS coil used in synchronous motor suffers inevitable current decay resulting from dynamic resistance, which is usually much...
With the merits of passive stability, energy-saved and environment-friendly, high-temperature superconductor (HTS) magnetic levitation (Maglev) is regarded as a promising candidate for the future high-speed transit. Amont the two main HTS maglev methods the bulk-type and stack-type, the stack-type HTS maglev is of the merits of larger engineering current density, larger loading potential and...
As one of the key components of synchrotron injection and extraction system, the septum magnet not only needs to produce a strong magnetic field to deflect the injection/ extraction beam, but also cannot affect the circulating beam passing by it. Otherwise, the disturbance of the leakage magnetic field to the circulating beam will affect the beam loss. Based on the theory of electromagnetic...
Our research has shown that an energy conversion/storage device composed of a permanent magnet and a superconductor coil has superior performance. In order to improve the conversion efficiency and energy storage capacity of this device. An effective method to enhance the interaction behavior between a permanent magnet and a closed superconductor coil is proposed in this paper. The functions...
Field shaper is a powerful supplement for the magnetic field generator (namely, the driving coil) in electromagnetic forming (a high velocity manufacturing technology), which utilizes the magnetic shielding effect of deticated-shaped electrical-conductor to alter the path of the pulsed magnetic field, so as to obtain the desired spatial distribution for the magnetic field as well as the pulsed...
A prototype bipolar correction magnet with permanent magnets, which is realized by rotatable permanent magnet rods, was fabricated and magnetic field measurements were performed. Based on the evaluation, improvement on the magnet structure is under study. The new design will be discussed here.
We explore methods for stabilization and control of persistent currents in high-temperature superconducting Bi-2223 coils. Several different techniques are considered, including flux transfer through inductive coupling as well as other novel approaches. These different methods are tested at 77 K using an experimental setup with a closed loop of Bi-2223 conductor powering two iron-dominated...
This paper deals with the fabrication and preliminary rotational test of an high-temperature superconducting (HTS) synchronous motor with linear-motor type flux pump exciters. This HTS synchronous motor is composed of copper armature windings, HTS field windings, linear-motor type flux pump exciters, vacuum chamber, cryogenic cooling system, etc.The various core components were manufactured,...
High-field magnets are often demanded for advanced scientific studies. Although a hybrid coil design comprising Nb-Ti, Nb3Sn, and HTS (High Temperature Superconductors) are potential candidates for such application, the costs of Nb3Sn and HTS are expensive compared with Nb-Ti. Permanent magnet can join hybrid magnets. By generating additional field about 1 T by permanent magnets, required...
For future larger and higher energy particle accelerator, the Fourth superconducting electron cyclotron resonance ion source (FECR) is building in Institute of Modern Physics, Chinese Academy of Science. In order to verify the technology of the Nb¬3Sn superconducting magnet for FECR, a prototype which consists of two axis solenoid coils and six sextupole coils with cold iron yoke has been...
The 9.4-T whole-body MRI superconducting magnet system with a warm bore of 800mm in diameter has been designed and fabricated in the Institute of Electrical Engineering, Chinese Academy of Sciences (IEE, CAS) for bioscience research applications. A passive quench protection system with the coil subdivisions and the heater network to accelerate quench propagation has been employed to avoid the...
VIPER cable is a high-current and high-field capable high temperature superconducting (HTS) cable designed by MIT and Commonwealth Fusion Systems (CFS) for large scale superconducting magnet system applications. The VIPER cable design is based on the high-temperature superconductor cable architecture known as Twisted Stacked Tape Conductor (TSTC) first proposed by Takayasu et al. [1]. Several...
In the framework of a joint collaboration funded by US Department of Energy (DOE), a large bore “Cable Test Facility Magnet” is under development. This is a joint effort between the Office of High Energy Physics (HEP) and the Office of Fusion Energy Sciences (FES). A 15 T Nb3Sn dipole magnet is being developed at Lawrence Berkley National Laboratory (LBNL). The magnet will produce the...
We have been developing the Frequency Loss Induced Quench (FLIQ) protection system for high-temperature superconducting magnets. We have studied the sensitivities of the various FLIQ system parameters to understand the design of an effective quench protection system. FLIQ drives AC current in the magnet coil and generates AC losses. The heating associated with the losses quenches the HTS...
Permanent magnets are necessary materials for particle accelerator components. As the beam intensity of the accelerator increases, demagnetization effects in permanent magnet materials is becoming one of the important issues. In order to measure the demagnetization rate of the magnet materials such as NdFeB, SmCo, and Ferrite magnets, a neutron irradiation experiment in Kyoto University...
Abstract: The segmented core reactor is small in size and low in cost. It not only has good electromagnetic compatibility, but also has a larger inductance value due to the multi-section air gap structure. However, under the interaction of electromagnetic force and magnetostriction at the air gap, the reactor core is deformed, causing vibration and generating louder noise than other ordinary...
We report on power test of a rapid-cycling superconducting accelerator magnet. The dual-bore magnetic core of 0.5 m length and two 10 mm (vertical x 100 mm (horizontal) beam gaps arranged in vertical plane is energized with HTS-based power cable. The 3-turn magnet cable is placed within magnetic core space where core descending magnetic field is strongly suppressed minimizing ramping B-field...
Magneto plasma sail is a space propulsion system with a higher fuel efficiency for future deep space explorations. The thrust to power ratio of the magneto plasma sail can be greatly improved with a superconducting magnet by generating a larger magnetic field with less power consumption. The thrust of the magneto plasma sail is produced by the transfer of momentum from a solar wind plasma to a...
- Introduction
Iron oxide scale removal from boiler feed water was studied to suppress the deterioration of power generation efficiency of the thermal power plants adopting oxygenated treatment (OT), by using high gradient magnetic separation (HGMS). Since the magnetic susceptibility and secondary particle size of the target particles have large effects on the magnetic separation efficiency,...
Removal of magnetic fine particles from a non-magnetic fine powder by high gradient magnetic separation under dry condition was studied. The dry magnetic separation has been partially put to practical use in the separation of iron from waste, the mining field, the food industry and so on. However, in the application of high-gradient magnetic separation (HGMS) with a stronger magnetic force,...
Quench detection is an indispensable part of the superconducting electrical device to ensure its safe and stable operation. For HTS cables with a length of several kilometers, Distributed Temperature Sensing (DTS) based on Raman Optical Time Domain Reflection (R-OTDR) has irreplaceable capacity such as continuous spatial measurement and long sensing distance, but the optical fiber needs to...
This presentation shows the effect of soldering between YBCO tapes on the inter-tape resistances in the stacked cables composing of dozens of YBCO tapes. The research and developments of a stacked cable with multiple YBCO tapes are ongoing as a candidate for large-scale conductors for fusion experimental devices. In this study, the inter-tape coupling losses in the cable composing of stacked...
During the years of ITER conductors qualification phases, samples from all domestic agencies were tested. Some of these tests were focused on characterizing the AC losses properties of the ITER conductors. The data produced originate from various facilities (SULTAN, University of Twente, CERN…), using different experimental protocols, for a large number of samples. The result is thus a...
This paper describes the design and the test result of the world’s most compact rotating gantry for heavy ion therapy system mounted with superconducting bending and focusing magnets that is successfully installed in East Japan Heavy Ion Center Faculty of Medicine, Yamagata University, Japan. Rotating gantry is a cylindrical irradiation equipment with magnets for beam transport and beam...
By the merits of self-stable levitation, low energy cost and no-contact friction, high-temperature-superconducting (HTS) pinning maglev system has a great potential to become an ultra-high-speed transportation. Recently, with the mature of the HTS pining maglev technology, the first HTS maglev engineering prototype vehicle was successfully established in our group. As the most important factor...
A method of removing microplastics from seawater using electromagnetic force was devised and its feasibility was demonstrated by calculation. Plastic is difficult to decompose and puts a heavy load on the marine environment. In particular, plastics smaller than 5 mm are defined as microplastics, which are carried over long distances by ocean currents and cause global pollution. The development...
A commercial micrometric Cu powder is mixed with Ag nanowires (diameter 0.2 µm, length 30 µm) synthesized in-house, in order to prepare a powder with a Ag content of 1 vol. %. Two powder batches are prepared for consolidation into cylinders (diameter 8 mm, length 33 mm) by spark plasma sintering.
One cylinder is sintered at 400 °C, where the solubility of Ag in Cu is below 0.1 vol. %, which...
Here we have studied the performance and quench properties of a large (outer diameter: 901 mm; winding pack: 44 mm thick × 50.6 mm high) conduction-cooled, react-and-wind, MgB2 superconducting coil. Minimum quench energy (MQE) values were measured at several coil operating DC currents (Iop ), and distinguished from the minimum energy needed to generate a normal zone (MGE). During these...
High field superconducting magnets require a large number of ampere-turn in their windings. To avoid large self-inductances in such magnets they must be wound using superconducting cables. Compared to other currently available HTS cables REBCO Roebel and CORC cables have their strands transposed or twisted which reduces both their ac losses as well as magnetization. This improves field...
Fusion for Energy (F4E), the European Domestic Agency for ITER, is responsible for the supply of ten out of 18 Toroidal Field Coils installed in the ITER machine. This article gives an update of the status of the cold test of the winding packs and their insertion into the Coil Cases being the last work package of the TF magnet production performed under the framework of an F4E contract...
In this paper, a REBCO thin film superconducting wire was fabricated by depositing materials with different specific resistance values (Ag) on REBCO superconducting wire, using the “RF Sputtering Deposition Method” with micro-range thicknesses to form the outer layer. Then the fabricated REBCO superconducting wire were subjected to basic characteristics tests (measurement of their temperature...
A Wireless Power Transmission (WPT) system for a railway vehicle has been investigating to reduce the greenhouse gas emissions in a diesel vehicle. Since the WPT system for the railway vehicle is required to transmit the electric power of several hundred kW in a short time, it is difficult to suppress heat generation by the internal resistance of a copper coil. Therefore, we have investigated...
HTS flux pumps enable superconducting currents to be directly injected into a magnet coil without the requirement for thermally inefficient current leads. As exciter of high temperature superconducting synchronous motor, HTS flux pumps will reduce the cryogenic volume and improve the efficiency of the HTS machine. With the air gap between the flux pump and the HTS stator increases, the...
This paper describes a design of a Vertical-ring High Gradient Superconducting Magnetic Separation (VHGMS) magnet for recovery of the magnetic ore and purification of non-metallic minerals. Compared to the conventional design which uses copper wires, using superconducting magnet can help reduce the energy consumption and increase the magnetic field. The first part of this paper introduces the...
Superconducting magnet protection must address two main areas of the magnet and circuit performance, namely Conductor Hot-Spots and Circuit Voltages. Both hot spot and voltage operational maximums are during the superconductor's transition called a Quench. Historically high voltages have resulted in many damaged and destroyed magnet coils so reducing voltages is a preferred direction for...
We propose a new active feedback control method to quickly charge no-insulation(NI) magnets, as well as sustaining thermal stability. The main feature of our suggested method is controlling ramping rate of the magnet to minimize consecutive Joule heating induced by the radial leakage current and resistive joint. The suggested method to be applicable for the iron core NI coils, dynamic...
Nb3Al has better the strain properties than that of Nb3Sn, but it is difficult to manufacture as a wire. In recent years, a research group of the National Institute for Materials Science (NIMS) in Japan has developed a new shape of ultra-fine and flexible Nb3Al superconducting. Jelly-rolled Nb/Al composite monofilamentary wires with an outer diameter of 30 m, and multi-strand wires were...
It has been fifty years since the first papers on the effects of magnetization in the superconductor in an accelerator magnet field quality were measured. The effects of conductor magnetization are most pronounced at low fields. By late 1971, a reliable method for estimating the effects of superconductor magnetization on the field quality in accelerator magnets was developed. A review of...
The superconducting tape stack has increasing impact on the applied superconductivity community due to the high field and current applications such as plasma confining magnets. The interlayer resistance of the stack, however remains a problem for the Coated Conductors (CCs) due to the ceramic buffer layer, which causes totally different behavior of the stack of CCs and the traditional low...
Abstract: The YBCO superconducting coils will cause complex deformation, and even moving between layers under the large Lorentz forces during energization. These will further disturb the magnetic field quality and the operating safety and stability. A more accurate estimation of the magneto-mechanical behaviors of YBCO coil during excitation is a crucial one. However, the conventional finite...
Metal plates are applied in high-temperature superconducting (HTS) magnet to provide a mechanical support and conduction cooling. The electromagnetic coupling between the metal plates and HTS coils has a considerable influence on the discharge operation of HTS coils during quench protection. In this paper, a multi-physics model is developed using circuit- field coupling method to study the...
Superconducting Magnetic Energy Storage (SMES) has the advantages of fast response speed, large energy storage density and low loss, which is suitable for dynamic power compensation of power systems. During operation, the superconducting magnet exchanges power with the AC grid through the power conditioning system (PCS). The PCS generally adopts a PWM converter based on a high-frequency ...
The magnetic center alignment is extraordinarily important before put a new ion-source into operation. Misalignment of ion-source may cause arc chamber destroyed. We take two methods to measure and align the ion-source superconducting magnet based on the cryostat bore in IMP. The required offset between ion-source magnetic center and mechanical center of warm bore is less than 0.5mm.
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For fluctuation suppression and energy compensation of the power system of the particle accelerators Booster and Nuclotron of NICA complex at JINR, 3 inductively coupled SMES coils are adopted. ASIPP is responsible for one of the three coils with 1 MJ energy storage. The inner diameter of the SMES coil is optimized to be 680 mm. The operating current is about 6 kA level and the pulse period is...
9 ITER TF coils are being manufactured in Japan for ITER project. Each TF coil consists of 7 Nb3Sn conductor double-pancakes (DP). In heat treatment of DP, strand witness samples are heat-treated with DP simultaneously and then their critical current (Ic) is measured to confirm soundness of the heat treatment. Recently, heat treatment of all of 63 DPs has been successfully completed under...
Since the 2G HTS tapes are made by a multi-layered thin film process, delamination occurs easily when stress is applied in the vertical direction of the tape. That is, in the cooling process of the superconducting coil, delaminations occur in the multi-layered HTS tapes when the stress value due to the difference in the thermal contraction rate of each material constituting the HTS tape is...
The Future Circular Collider would require a high-field septum magnet with a possibly thin blade for the extraction of the 50 TeV proton beam from the ring. One of the two baseline concepts in the conceptual design report is the "superconducting shield" (nicknamed as SuShi) septum, utilizing a zero field cooled, passive superconducting shield in order to create a zero-field channel inside the...
SIGRUM (Superconducting Ion Gantry with Riboni’s Unconventional Mechanics) project comes from the strong collaboration between ‘Centro Nazionale di Adroterapia Oncologica’ (CNAO), in Pavia, Italy, and CERN. This centre, relying on CERN experience in accelerator particles, wants to improve cancer treatments with a novel superconducting ion gantry structure.
The magnet is operated at a...
No-insulation (NI) winding technique shows superior electrical and thermal performance for high temperature superconducting (HTS) coils compared with the insulation winding technique. However, the NI HTS winding technique is uncertain about the thermal contact resistance between winding turns because the HTS wire has various surface conditions such as roughness and oxidation. In this paper,...
Heavy-ion radiotherapy has a high curative effect and low burden on patients, so it has been spreading in recent year. On the other hand, since heavy-ion radiotherapy system have large apparatuses such as injector, synchrotron, and rotating gantry, it is necessary to downsize these apparatuses in order to further wide spreading. Therefore, a project to develop a next generation small facility...
High Temperature Superconductors (HTS) is a promising option for high current Cable-In-Conduit Conductors (CICC) for large high-field magnets. CICC are often constructed from several HTS strands which themselves are formed from individual HTS tapes. Quench propagation is CICCs is currently under intensive investigation, and it can be predicted by modelling the entire structure. However, for...
To prevent global warming, CO2 emission by aircrafts is required reduction. For that purpose, the electric propulsion system is focused on as a promising technology. That system enables the aircraft to adopt distributed propulsors which have a great advantage from the viewpoint of aerodynamics. That system contains rotating machines; however, the conventional ones cannot satisfy the stringent...
In September 2018, China Spallation Neutron Source (CSNS) passed the national acceptance and started stable operation. Many scientific achievements have been made, but more and more experiments require accelerators with higher beam quality. Based on the current Lattice layout and further research, an alternative upgrade plan is proposed for RCS, which will become the formal design scheme of...
An infiltration and reaction (IR) process realizes the dense MgB$_2$ bulk without the external physical pressure. The trapped field, $B_{\rm T}$, of MgB$_2$ bulk prepared by the IR process was 2.4 T at 15.9 K, which was as high as that of MgB$_2$ bulk prepared by in-situ hot isostatic pressing method [1]. However, we found quite a large amount of unreacted micrometric B particles due to the...
A quasi-microgravity space, exploiting a large magnetic field in combination with a large field gradient, is considered for potential applications such as protein crystallization and cell culture without natural convection caused by gravity. To provide a high magnetic field in a more cost-effective way, large-single grain bulk superconductors – such as the RE-Ba-Cu-O (RE: rare earth element or...
The intermittent characteristics and low system inertial are two major problems for the renewable energy sources (RESs) dominated power system. This paper proposes the novel idea of integrating the wind and photovoltaic power generators with a superconducting magnetic system (SMES) as a whole to behave as a grid-forming renewable energy system. The proposed grid forming system can provide...
Since the beginnings of NMR spectroscopy, the exceptionally successful method to analyze the chemical structure of solids and molecules in solution, experimentalists requested ever larger magnetic fields for their instruments, primarily to improve their resolution and their signal-to-noise ratio. While a succession of low-Tc superconductors – NbTi and a range of Nb3Sn wire types – were the...
This summer the US HL-LHC Accelerator Upgrade Project (AUP) reached an important milestone by completing 50% coil fabrication. AUP is fabricating half of the low beta quadrupoles (MQXFA) for the High Luminosity LHC (HL-LHC) at CERN. These magnets will be used in Q1 and Q3 Inner Triplet (IT) elements of HL-LHC. CERN is fabrication the magnets for Q2a and Q2b IT elements. The AUP effort is...
We present the operation result of a liquid-helium-free 23.5-T/φ12.5-mm-cold-bore magnet prototype composed of a stack of 10 no-insulation (NI) REBCO double-pancake (DP) coils: eight middle coils of 6-mm wide and two end coils of 8-mm wide tape. All the tapes have only 1-µm-thick copper layer on each side to overcome the conductor thickness uniformity issue and enhance the mechanical strength...
Korea Medical Device Development Fund (KMDF) launched a national project to develop a high-temperature superconductor magnet for magnetic resonance imaging (MRI) in 2020. This project's ultimate target is to develop a 6 T 320 mm high temperature superconductor (HTS) magnet. Major concerns in developing the MRI magnet in terms of electromagnetic dynamics are the time-varying field uniformity...
New high field and large-aperture quadrupole magnets for the low-beta inner triplets (Q1, Q2, Q3) are being built as part of the high-luminosity upgrade of the Large Hadron Collider (HL-LHC). These new quadrupole magnets are based on Nb3Sn superconducting technology. US Accelerator Upgrade Project (US-AUP) is producing the Q1 and Q3 cryo-assemblies; a pair of ~ 5 m long magnet structures...
This work concerns the development of non-insulated (NI) HTS magnets at the Paul Scherrer Institute (PSI), Switzerland.
The Swiss Light Source (SLS) synchrotron at PSI uses superbend magnets as a brilliant source of X-rays. As part of an upgrade of the SLS, two LTS superbends are being constructed. These NbTi-based magnets will each consist of a pair of racetracks to generate the desired...
In recent years, remarkable progresses have been made in the R&D efforts for HTS high-field magnets. The screening-current-induced magnetic field (SCIF) and mechanical stress/strain (SCIS) in REBCO coils are raising growing concerns. This study presents experimental and theoretical analyses on the SCIS in two REBCO coils, with and without over-banding structures, as inserts in an LTS...
The High-Luminosity project (HL-LHC) of the CERN Large Hadron Collider (LHC), requires low β* quadrupole magnets in Nb3Sn technology that will be installed on each side of the ATLAS and CMS experiments. After a successful short-model magnet manufacture and test campaign, the project has advanced with the production, assembly, and test of full-size magnets. In the last two years, two CERN-built...
HTS is valuable for future detector magnets as it allows operation at elevated temperatures and magnetic fields. However, due to slow propagation of normal-zones, quench protection remains a challenge. Non-insulated coil technology offers a potential way forward, but controlling the associated ramping time constant is still an unresolved challenge. This study offers a potential way to have...
The high-strength substrate within REBCO contributes to its selection for use in the NHMFL 40 T all-superconducting magnet. To confidently scale up to a 40 T user magnet, both quench protection and cyclic fatigue are among the technologies that require successful demonstration. Here, numerous test and simulation results from two-in-hand wound, double-pancake stacked, insulated mid-scale test...
High-temperature superconducting (RE)Ba2Cu3O7-x (REBCO) coated conductor (CC) tapes are known for their capacity to tolerate high tensile stress under applied uniaxial tension, typically in the range of 600-700 MPa at 77 K, while mediocre level under pure bending (a.k.a., easy bending). Once utilized in coil, however, there is a limit to the value of the allowed strain/stress before...
We have succeeded in operating a 25 T cryogen-free superconducting magnet (25T-CSM), which consists of LTS outsert coils and Bi2223 insert pancake coils. As a next step, an upgrading of 25T-CSM to 30T-class CSM is considered by replacing the Bi2223 insert coils with REBCO coils, since REBCO tapes have better mechanical and in-field critical current properties. In a design of the 30T-CSM, the...
INFN is developing at the LASA lab (Milano, Italy) the High Order (HO) corrector magnets for the High Luminosity-LHC (HL-LHC) project, which will equip the new interaction regions. All the HO correctors, from skew quadrupole to dodecapole, are based on a novel superferric design, never used so far in high energy colliders, which allows a relatively simple, modular, and easy way to construct a...
In order to achieve high intensity and compact multifunctional cyclotron, the behavior of the non-circular coil in a high magnetic field at 4.2 K, and the reinforcement of it have been investigated. Two types of isosceles triangle shaped double-pancake coils; a coil with reinforcement due to Yoroi-coil (Y-based oxide superconductor and reinforcing outer integrated coil) structure and a coil...
Large aperture beam separation dipole (MBXF) will be constructed as a Japanese contribution for the High-Luminosity LHC upgrade. Those magnets will be installed at both sides of two interaction points, ATLAS and CMS. The required field integral is 35 Tm with the coil aperture of 150 mm. Nominal dipole field of 5.6 T at the nominal current of 12 kA is produced at 1.9 K by Nb-Ti based...
MCBXFB magnets are nested orbit combined correctors for the upgrade of the LHC. The first three magnets have been manufactured at CIEMAT and assembled at CERN, in the framework of the HL-LHC project. The power tests performed on the first prototype showed that the behaviour when the dipoles were individually powered was excellent, but the training to reach nominal currents in combined...
A 14 T whole-body MRI superconducting magnet is currently being designed at the Institute of Plasma Physics Chinese Academy of Sciences. The main coils will be wound with the Nb3Sn Rutherford cable-in-channel conductors, actively shielded, and operate at 1634 A to produce a central field of 14 T in an 840 mm warm bore. The magnetic field homogeneity is 5 ppm in a 45cm DSV. The inductance is...
Advanced Conductor Technologies has been developing high-temperature superconducting (HTS) Conductor on Round Core (CORC®) cables and wires wound from ReBa2Cu3O7- coated conductors for use in high-field magnets that would ultimately operate at fields exceeding 20 T. CORC® cables and wires have matured into practical high-current and high-current density magnet conductors that are being...
From a magnet designer’s point of view Bi-2212 round conductor is, in many aspects, the ideal candidate for high field magnets. Besides very high critical current densities that exceed specification for conductor of the Future Circular Collider (FCC) of 1500 A/mm2 in 16 T background, it offers two particular advantages over other HTS conductors, namely that it is available as an up to one mile...
The U.S. Magnet Development Program (USMDP) is developing Canted-Cosine-Theta (CCT) magnet technology for future high field accelerator magnets. The CCT concept limits Lorentz force accumulation by placing turns within precision-machined grooves that are separated by ribs and a spar that intercept forces, substantially reducing the stress in the conductor. CCT technology has been advanced...
Future high energy particle colliders are under study, with a first goal of 16 T dipoles, which is believed to be the practical limit of $Nb_3Sn$ magnets. Another more ambitious goal is to aim for 20 T dipoles. This very high field would require High Temperature Superconductors (HTS), such as Bi2212 or REBCO. Their substantially higher cost necessitate anyways the use of Nb3Sn for an...
R2D2, the Research Racetrack Dipole Demonstrator, is a short model being developed within a collaboration between CEA Paris-Saclay and CERN aimed at developing key technologies for future high field 16 T $Nb_3Sn$ magnets for particle colliders. In the particular case of block-coil designs, two different cable grades are wound in the same coil layer, in order to maximize the current density,...
A dipole magnet generating 20 T and beyond will require high-temperature superconductors such as Bi$_2$Sr$_2$CaCu$_2$O$_{8−x}$ (Bi-2212) and REBa$_2$Cu$_3$O$_{7-x}$ (RE = rare earth, REBCO). Symmetric tape round (STAR™) wires based on REBCO tapes are emerging for such an application especially because of their unique tolerance to bending to a radius as small as 15 mm. Although STAR™ wires...
A project aiming to fabricate an operational Nb3Sn superconducting undulator for the storage ring of the Advanced Photon Source at Argonne National Laboratory is under way. The Nb3Sn undulator has a design magnetic field of 1.2 T and a nominal operation current of 850 A. The maximum magnetic field on the conductor is about 5 T. With large critical current densities, the 35 µm subelement size...
Double-Stator-Single-Rotor (DSSR) surface mounted Permanent Magnet Synchronous Motor (PMSM) has the advantages of small size, light weight and high reliability. However, there are problems of large torque ripple and abundant back-EMF harmonic content. In order to improve the electromagnetic performance of the motor, a double-stator single-rotor field modulated motor (DSSR FMM) with high...
Superconducting magnets used in particle accelerators produce magnetic fields of high precision and uniformity to bend or focus the particle beam. For such magnets, the development of accurate and efficient numerical methods for the evaluation of the magnetic fields is of high importance. This work presents a hybrid Finite/Boundary Element Method (FEM/BEM) scalar potential formulation,...
Construction of a new primary proton beam line, which is called B-line, started in 2013 at the J-PARC Hadron Experimental Facility. The B-line is branched at the middle of an existing primary proton beam line (A-line) in the beam switching yard (SY), which is the connecting tunnel between the Main Ring (MR) and the Hadron experimental hall (HD-hall). At the branching point, about 0.1% of the...
Magnetic gear (MG), as a kind of non-contact transmission component, has many advantages, such as no friction, oil-pollution free, low maintenance and easy installation, and so on.This paper proposes a novel coaxial magnetic gear (CMG) with eccentric permanent magnet structure and unequal Halbach arrays for achieving sinusoidal air-gap flux density and high output torque. The proposed model...
The magnetic field modulation type magnetic gear composite motor is a new type of motor integrating magnetic gear and permanent magnet brushless motor. Its advantage is that it has higher torque density and efficiency, and has a good application prospect in the field of low speed and large torque. According to the principle of magnetic field modulation, the air gap magnetic field of the...
A quench detection system was developed for protecting and monitoring the superconducting solenoids for the Muon-to-Electron Conversion Experiment (Mu2e) at Fermilab. The quench system was designed for a high level of dependability and long-term continuous operation and is based on three tiers: Tier-I, FPGA-based Digital Quench Detection (DQD); Tier-II, Analog Quench Detection (AQD); and...
A tri-axial high temperature superconducting cable has the advantages of small size, large transmission capacity, low AC loss and high economic efficiency in power transmission of urban city. The essential difference between superconducting cable and traditional cable lies in their unhindered current-carrying characteristics. But when carrying alternating current or changing electromagnetic...
AC loss reduction is essential to apply high temperature superconducting (HTS) conductors to power devices. We have studied the effect of AC loss decrease of CORC that is a low-loss and high-current conductor. The currents through CORC are equally distributed to the CORC strands (HTS tapes) because the strands are helically arranged around a cylindrical former. We have confirmed that the AC...
Rapid-cycling synchrotrons (RCSs) are desired as the main component of radiotherapy facilities for cancer treatment in order to meet growing patient numbers. Superferric magnets consisting of high temperature superconducting (HTS) coil windings and iron cores are considered to be an effective solution for reducing construction cost and electricity consumption for RCSs. However, superferric...
The onboard high temperature superconducting (HTS) magnet of electrodynamic suspension (EDS) train suffers from the external magnetic fields generated by the ground coils including the suspension coils, propulsion coils and even generator coils. In such case, the ac losses will be produced in the HTS magnet and lead to a rise in temperature, possibly affecting the operation stability of the...
R&D on joints between superconducting wires or tapes is one of the most important issues for the development of large-scale superconducting applications such as magnet, rotation machine and so on. Although the electro-magnetic properties between superconducting joints have been evaluated in several ways, the interfacial structure of the joint should also be investigated in order to sufficient...
The No-insulation (NI) REBCO as an insert magnet has been applied to overcome the field limitation of LTS NMRs. So far, NI REBCO pancake coils have shown a “self-protecting” characteristic in experiments and, consequently, basic mechanism of self-protecting from thermal runaway has been widely studied by analyses under a low magnetic field or cooled by liquid nitrogen. However, several HTS...
High current cables for large fusion magnets can be composed of hundreds of tapes. A convenient way to deal with such large number of tapes is multi-stage cabling. The stack of tapes is a basic element for the first stage of various high current cables designs. AC losses have been evaluated analytically in the limits of very low and very high sweep rates, providing a global overview of losses...
Abastract: Currently, a new gas-filled recoil separator Spectrometer for Heavy Atoms and Nuclear Structure 2 (SHANS2) is being developed and designed at IMP (Institute of Modern Physics, Chinese Academy of Sciences). It will be used to synthesize and study the superheavy elements, including their physical and chemical properties. The SHANS2 include two dipole magnets and three quadrupole...
One of the technical issues in the application of High Temperature Superconducting (HTS) tapes is the need to wind long tape sections with uniform electric properties along their length. In recent years, the No-Insulation (NI) winding technique for HTS coils is emerging as a valid alternative to conventional insulated coils, as it allows a more effective current redistribution from the most...
Low resistivity joint technique for high-Tc superconducting (HTSC) tapes is one of the most indispensable techniques for practical applications. At the present time the solder joint technique is widely used for joining HTS tapes for the non-superconducting joint. However, in the case of a joint using a solder, the resistance across the joint cannot be very low because of relatively high...
Stress management techniques have shown great potential to mitigate the high level of stress appearing in high field accelerator magnets, which is especially critical for stress-strain sensitive superconductors, such as Nb3Sn or HTS. The Canted-Cosine-Theta (CCT) concept provides an effective method to intercept the Lorentz forces of each turn, leading to a lower stress accumulation...
In recent years, there has been a renewed interest in the suitability and use of the Bi-2212 wires in various fields of application. Many studies highlight the possibility to use Bi-2212 for high magnetic field magnets above 18-20 T.
The purpose of this work is to study the electrical properties of Bi-2212 wires at temperatures above liquid Helium. The samples were obtained via a novel...
No-insulation (NI) technique has been proved to be an available approach for improving the thermal stability as well as the highest operating current of the high-temperature superconducting (HTS) coil. Nevertheless, the NI HTS coil suffers from a non-negligible charging delay inevitably. To address this issue, the parallel co-wound technique is a possible way. For investigating the performance...
Whole body ultra-magnetic field 14 T magnetic resonance imag-ing (MRI) magnet is now under design at Institute of Plasma Physics, Chinese Academy of Sciences, the main coil based on the preliminary designed of Nb3Sn Rutherford cable in Channel Conductor (RICC). Rutherford cable is a core components of the conductor. During the fabrication process of Rutherford cable, the strands were subject...
In the framework of the High-Luminosity Large Hadron Collider (HL-LHC) project, 11 T dipole and MQXF quadrupole magnets employing Nb3Sn technology have been tested in short and long test configurations. Nb3Sn magnets are more sensitive than NbTi magnets to a potential degradation of their conductors during production, testing and cycling operation. In the SM18 magnet test...
For future 20+ T accelerator type magnets, ReBCO tape based conductors are ideal for their capability of carrying high current densities in high magnetic field. At CERN, demonstrator dipole magnets using ReBCO conductor are being developed in order to study the feasibility of this technology. A key problem in such magnets is how to realize the coil ends when using ReBCO tape conductor without...
There is a huge energetic potential associated to ocean waves, expressed in terms of the power per wave meter length that can be harvested, up to 60-80 kW/m in many areas near to the shore of populated areas. Among the different devices proposed to extract that power, the most extended ones are the Point Absorbers, based on the linear displacement between two bodies for which the use of...
The construction of European demonstration power plant (DEMO) aims to employ high temperature superconductors (HTS) as the main magnets to avoid the requirement of large amounts of helium for the cooling system. The central solenoid coils which is transported with AC current in the reactor should be ensured of their operation condition to avoid quench phenomenon under a high temperature...
The super high field magnets using superconducting wires have been promisingly applied for thermonuclear fusion power generation such as Korea Superconducting Tokamak Advanced Research (KSTAR) and International Thermonuclear experimental reactor (ITER) systems. The quench detection system (QDS) is essential for high reliability in the super high field magnet facilities. Generally, the quench...
There are demands for mobile microwave power sources for different applications, such as the rock melting and drilling, for example. The 28 GHz gyrotron has been proposed as radiation source for such purpose [1]. For frequency ~ 28-30 GHz or more magnetic field ~1-3 T are needed for resonance interaction of the electron beam with eigenmodes of a circular waveguide at gyrodevices. Magnetic...
High energy physics research will need more and more powerful circular accelerators in the next decades, in order to explore unknown regions of particle physics. It is therefore desirable to have dipole magnets able to produce the largest possible magnetic field, in order to keep the machine diameter within reasonable size. A 20 T dipole is considered a desired achievement, since it would...
Recently, the development of the concept project of the high magnetic field (HMF) tokamak continues in the Russian Federation. The value of the magnetic field on the plasma axis in the device is about 8 T. The maximum field on the winding of the toroidal field coils is about 16 T. The generation of a high magnetic field in a limited space of tokamak-type device with a given aspect...
Striation (multifilament) is an effective way to reduce AC losses in the coated conductors for the applications of magnets or electrical power devices. Considering the robustness of the striated coated conductors, it is preferred to have some transverse conductance like copper between superconductor filaments. In such a conductor, however, the striation works for AC loss reduction only after...
The reduction of large AC losses in ReBCO coated conductors caused by their wide tape shape is a critical issue for their power applications. In principle, striating the wide superconductor layer of a coated conductor into narrow filaments (multifilament) is effective for the AC loss reduction. However, this approach is effective only when the filaments are decoupled electromagnetically, i.e....
In this paper, a new configuration of self-shielding DC HTS cable with a “sandwich” structure by interleaving winding is proposed. The distributions of the magnetic field and the critical currents in traditional DC HTS cable and self-shielding DC HTS cable are analyzed and compared in detail. The simulation results show that the self-shielding DC HTS cable can minimize the outer magnetic field...
The use of high temperature superconducting (HTS) materials is promising for both DC and AC power applications and for high field magnets. However, HTS coils must be carefully protected against quench, since the formation of hot spots can damage the materials even more severely than in the case of low temperature superconducting coils. A possible solution to this issue is offered by the use of...
High-temperature superconducting (HTS) magnets have been widely studied for practical applications of NMR, MRI, and medical accelerators. 2nd-generation HTS, REBCO (Rare-Earth Barium Copper Oxide), coated conductors (CC) have a high critical field and excellent electrical properties, compared to other superconducting conductors. REBCO pancake coils using the no-insulation winding technique can...
This study analyzes the current bypass mechanism of a metal stitching smart insulation (SI) coil rolled by coating vanadium oxide (V2O3) on a metal stitching wire prepared by generating micro-holes into a second generation (2G) high-temperature superconducting (HTS) wire using a laser and by filling the micro-holes with metal solder material. Results showed that the metal stitching wire with...
Whole body ultra-magnetic field 14 T magnetic resonance imag-ing (MRI) magnet is now under design at Institute of Plasma Physics, Chinese Academy of Sciences, the main coil based on the preliminary designed of Nb3Sn Rutherford cable in Channel Conductor (RICC). Rutherford cable is a core components of the conductor. During cabling the strands are inevitably experience plastic deformation that...
High field magnet technologies are supported by the development of advanced superconducting (SC) cable constructed from the composite SC tape. The SC tapes in the helically wound composite cable experience flatwise as well as edgewise bending load together with tensile one. We analyzed precisely the influence of uniaxial tensile load to critical current (Ic) of BSCCO tapes, where the...
In the framework of the consolidation of the Antiproton Decelerator (AD) Target Area it was decided to replace the two original normal conducting quadrupoles used for the final focussing of the proton beam before the target by two 1-m-long quadrupoles based on permanent magnet technology. Their gradient is adjustable from 35 to 45 T/m inside an aperture of 60 mm in diameter. This paper...
Compared to low temperature superconductor (LTS) based fusion conductors, the use of high temperature superconductors (HTS) offers the possibility to increase the magnetic field strength in future fusion reactors, allowing higher flux swing or even more compact fusion reactors. REBCO, the most promising HTS material, is commercially available as coated conductor tape. Opposed to LTS wires,...
Particle spin physics research at Nica collider deals with polarized proton and deuterium beams. Special solenoids are proposed to control the spin direction of the polarized beams in NICA. Spin direction can be controlled by adjusting the integral of axial magnetic field of the solenoids. We present design results for 6T polarization control superconducting magnets for NICA collider. The...
A 14T physical property measurement system (PPMS) magnet with cryogen free is being developed in Institute of Electrical Engineering, Chinese Academy of Sciences (IEE, CAS). Unlike steady-state magnets such as NMR, MRI, the PPMS magnet is required to be excited frequently and the excitation rate usually needs very high, for example in 30min to reach the full magnet field. The fast excitation...
Large aperture superconducting combined function magnets with the magnetic rigidity of 13Tm will be utilized in the Spectrometer-Ring for the HIAF (High Intensity heavy-ion Accelerator Facility) project. The magnet is designed to provide a dipole field of 3.0 T and a quadrupole field of 11.3 T/m in a large aperture of 240 mm. The Canted Cosine Theta (CCT) superconducting magnet had been well...
This paper describes a simple, compact and cost-effective capacitor pulse power supply, which only uses a single magnet coil and two capacitors of different voltage and capacity levels to form a special circuit structure. It can realize the pulse magnetic field similar to the flat top wave, so as to meet some scientific experiments that require higher magnetic field strength and stability....
Flat-top high magnetic field (FTMF) is a significant research method for physics, chemistry, biology and other scientific fields with the demands for higher magnetic intensity, longer flat-top pulsed width and a lower ripple. To meet these demands, a new FTMF system based on multiple-capacitors power supply has been realized at the Wuhan National High Magnetic Field Center in March 2021....
Large-size aluminum alloy rings are widely used as connector, transition ring and reinforcing structure in aerospace and other fields. Their performance determine the service life, assembly accuracy and reliability of the equipment directly. However, the residual stress introduced during the manufacturing process lead to the structural instability and poor mechanical properties of the aluminum...
Coated superconductor magnets have already proved their feasibility in electrodynamic suspension (EDS) application as the on-board magnet, making the liquid-helium-free EDS train become possible. This paper designs a racetrack REBCO magnet served as the on-board magnet of EDS train, including the designs of both the REBCO coil composed of eight double pancake (DP) coils and the tailored...
Superconducting undulator (SCU) technology has been in use at the Advanced Photon Source since 2013. Due to the successful and reliable operation of the existing SCUs, the Advanced Photon Source upgrade project has decided to expand the use of NbTi-based SCUs. The first new magnets to be designed and fabricated are 1.9 m long with a period length of 16.5 mm. NbTi superconductor is used for...
FASER, the ForwArd Search ExpeRiment, is designed to search for new, yet undiscovered, light and weakly-interacting particles and study the interactions of high-energy neutrinos. Three dipoles are required to achieve sufficient separation of pairs of oppositely charged, high-energy Standard Model particles originating from decays of new physics particles. The first magnet is 1.5-m-long and...
The CSR external-target experiment (CEE) will be China’s first self-developed nuclear research experimental facility operating in the GeV regime based on the large-scale scientific facilities HIRFL-CSR. One of its core components is a dipole magnet with a large gap and wide acceptance. Unlike traditional large spectrometer magnets, the physical target of the CEE requires a highly stable,...
The NUCLOTRON type cable has been chosen for developing a fast cycled superconducting dipole for the booster ring of the HIAF project at IMP. The splices of the cable are key components for the magnet. A design which has a resistance about 10-9 Ohm and is easy to be fabricated is developed. The structure of the joint is optimized with Opera software. And reliable fabrication process is...
In the aluminum industry, development of highly efficient and fast heating methods of aluminum billets is expected. The induction heating by rotating the aluminum billet in strong DC magnetic field generated by HTS coils is one of the candidates for the heating methods in the aluminum extrusion processes, since this method has the large heating capacity with higher energy efficiency and faster...
Reducing AC losses in coated conductors is one of the important issues for HTS applications to electric power devices and magnets. Multifilament structure is a method to reduce AC losses. From the view point of improving the robustness of a multifilament coated conductor for local normal transitions, it is preferable to have a finite transverse conductance. When copper is plated over the...
We have been developing radiation-resistant warm magnets insulated by a Cyanate ester resin. We developed a glass fiber cloth prepreg tape using Cyanate-ester pre-polymers supplied by Mitsubishi Gas Chemical Corporation INC. The proton beam irradiation test was carried out for the evaluation of the radiation hardness. We prepared cured resin samples of Cyanate ester, Bismaleimide Triazine...
It is expected to build a sustainable social system that uses "hydrogen" as a fuel to generate electricity without emitting CO2. To realize this, technology for storing a large amount of hydrogen is indispensable, and storage as liquid hydrogen is ideal. However, the efficiency of the cooling device in the temperature range around 20 K required for long-term storage with liquid hydrogen is...
High-temperature superconductors such as REBa2Cu3O7-x (REBCO) can generate strong magnetic fields that are promising for applications in particle accelerators and compact fusion reactors. Lawrence Berkeley National Laboratory is developing magnet technology-based multi-tape REBCO cable conductors. Traditionally, voltage taps are installed in superconducting magnets. The voltage signals due to...
Dynamic loss is an essential parameter to consider for the design of high temperature superconducting (HTS) synchronous machine windings. For HTS coated conductors (CC), the existing definition of dynamic loss only considers the HTS layer, the validity of which compound with magnetic substrate is questionable. In response to the above concern, by use of the H-formulation based numerical...
Due to the extensive application of soft magnetic materials in transformers, motors, reactors and other electrical equipment, the research of accurate iron loss prediction method becomes an indispensable part to ensure the safe operation of power system and to realize the optimal design of electrical equipment. However, the development of appropriate methods for predicting iron loss is...
The world’s first full-sized high-temperature superconducting (HTS) Pinning magnetic levitation (maglev) engineering prototype train was officially launched in SWJTU, Chengdu, China in 2021. This prototype provides strong proof for the feasibility of engineering application of HTS pinning maglev in civil train. This prototype shows the basic load and low speed operation capability of HTS...
Development of high temperature superconducting REBa2Cu3Oy (REBCO, RE: Y and rare earth) coated conductors (CCs) would enable cost-effective magnet applications in rotation machines, generators for wind turbine and magnet use in medical imaging machines. To use for these applications, precipitates and structural defects with nano-meter size have been introduced in REBCO films to enhance...
GdBa2Cu3O7-δ (GdBCO) has high critical current density (Jc) of the order of 106 A/cm2 at 77 K in self-field and higher critical temperature (Tc) than that of YBa2Cu3O7-δ. Therefore, GdBCO coated conductor (CC) has been expected as a promising wire material. For the wire application, superconducting joint of CC has been required to lengthen them. In our previous work, superconducting joint of...
The brittle intermetallic Nb3Sn superconductor is currently being used to develop high field magnets in the framework of the Hi-Luminosity upgrade of the Large Hadron Collider at CERN. Despite its excellent superconductive properties, Nb3Sn wires suffer from significant critical current Ic reduction due to the transverse load applied during the magnets’ assembly and energization.
A...
China Fusion Engineering Experimental Reactor (CFETR) is a major scientific project independently designed and developed by China and jointly with international cooperation. Engineering design and project infrastructure construction are currently underway. The design goal of CFETR is 1.5-2.0 GW fusion power, and the central magnetic field is up to 17 Tesla, which is much larger than the design...
V2O3 has been studied as a smart insulation material for 2G high-temperature superconducting (HTS) coils owing to its remarkable metal-to-insulator transition (MIT) upon heating or cooling via a critical temperature (Tc) of ~160 K. The smart insulated (SI) coil regulates its function according to the MIT properties of V2O3. At temperatures below Tc, V2O3 acts as an insulator, whereas it...
The Facility for Rare Isotopes Beams (FRIB) employs an advanced fragment separator for the efficient production and purification of the in-flight rare isotope beams. At the first stage, the incoming primary beam from a production target experiences an initial separation from the products of interest. A large phase secondary beam needs to be purified and focused with magnetic multipole elements...
The design and operation of resistive high field magnets require research and development in materials science, power supply engineering and instrumentation. Additionally, their energy efficient operation has become a growing constraint. The French National High Magnetic Field laboratory at Grenoble (LNCMI) is continuously improving its high magnetic field platform in order to satisfy the...
In REBCO tape having multi-layered structure, resistance of Cu/Ag and Ag/REBCO interfaces (interface resistance) is one of the major factors of joint resistance of tape-to-tape joints. Since the interface resistance depends on the manufacturer and/or lot number of REBCO tapes, it is necessary to evaluate the interface resistance beforehand at temperatures and magnetic fields of the operating...
The High Temperature Superconducting (HTS) magnet system is immersed in a sub-cooled liquid nitrogen (LN2) and continuously refrigerated by a cryogenic cooling system. Especially, in case of the side-wall cooling type, the HTS magnet system is located well below the level of LN2 for thermal and electrical safety and the cryogenic gaseous nitrogen (CGN2) is filled above LN2. However, the method...
Abstract: The YBCO racetrack pancake coils were wound by dry wing followed by impregnation. Various materials such as epoxy resin, paraffin, grease and so on with and without fillers were measured to impregnate coils. The superconducting characteristics of the coils after above different materials of impregnation were tested. Due to the anisotropic of the racetrack shaped coils, the...
In high-temperature superconducting films and tapes, optical switching are complex and are determined not only by the laser pulse energy, but mainly by its duration. Thermal processes play the main role at durations from tens to hundreds of ps. To study the physical processes occurring in an HTS tape under ultrashort laser irradiation, using the Comsol Multiphysics software, a multiphysics FEM...
Recent years have seen significant development of high-temperature superconducting Bi-2212 wires and magnets in the US with record critical current density, record wire lengths and record performance model magnets. A dozen racetrack coils have been produced within the LBNL subscale accelerator magnet program using Bi-2212 Rutherford cables, including the record performance of RC6, which...
Fermilab has been developing flexible printed circuit board (flex-PCB) based quench antenna (QA) probes since 2017, and these have seen a variety of improvements and customization for different applications over the years. The flex-QA have proven to be low-noise, low-cost, non-invasive, and highly sensitive sensors for quench characterization in superconducting magnets, with potential to...
Characteristics of fly-wheel type uninterrupted power supply (FW-USP) using superconducting induction machine (SIM) is analytically studied. In the study, it is assumed that the SIM is iron-cored and composed of Cu wire stator windings and HTS rotor windings. The rotor windings are made with HTS wires embedded in an iron rotor core and connected to HTS end-rings. The whole assemble of the...
The Nb3sn was prepared successfully by two methods of mechanical alloying followed by their respective heat treatment process. The microscope morphology, crystal structure, and superconducting properties were investigated. From the results, mechanical alloying was an effective method to produce the precursor, which changed the reaction formation energy of Nb3sn and can produce Nb3sn more...
The weight loss of the organic composite materials and their matrix resins have been measured in vacuum. These are intended for use as insulating materials of fusion superconducting magnets or as structural materials used in aerospace application. Since in these applications they are used under the radiation environments, the degradation of mechanical strength will be measured together with...
Significant progress has been made recently in the U.S. Fusion community to develop a strategic plan to enable engineering design and construction of a Fusion Pilot Plant (FPP). Princeton Plasma Physics Laboratory (PPPL) is working on developing high performance HTS conductors for fusion, and partnering with the U.S. industry, we are evaluating feasibility and affordability of cable on round...
Null-flux Electro-dynamic suspension (EDS) system promises to be one of the feasible high-speed maglev systems above 600 km/h. Due to its greater current-carrying capacity, superconducting magnet can provide super-magnetomotive force that is required for null-flux EDS system and cannot be provided by electromagnets and permanent magnets. There is already a relatively mature high-speed maglev...
To get an understanding of the magnetic field distribution in a superconducting magnet, computer simulations are needed which take into account the actual geometry of the magnet and the magnetic saturation in different materials. It is a further advantage that the software efficiently tackles the large number of unknowns needed for accurate 3D simulations and also allows the coupling of...
Compared with conventional power cables, high-temperature superconducting cables (HTS) have the advantages of large current capacity, low loss, compact structure, and no electromagnetic radiation. With the continuous improvement of electricity consumption in all of the world, HTS cables are of great significance to improving the transmission capacity of power systems. Because the HTS cable has...
In order to develop high temperature superconducting (HTS) tapes with excellent low-loss characteristics, a measurement system that enables us to measure AC loss characteristics of HTS tapes with high sensitivity is indispensable. We have successfully reduced background losses, which are apparent losses obtained by a pickup coil method in case where no specimen is located inside pickup coils....
The superconducting joint is one of key technologies to evolve high temperature superconducting (HTS) conductors and their applications. Various joint techniques have been proposed in these years [1]. To evaluate developed joint efficiently, we developed a resistance evaluation system for superconducting joints [2]. The system consists of a superconductor sample with a joint, a copper coil to...
An aluminium stabilized superconducting cable is developed for the Circular Electron Positron Collider(CEPC) detector magnet. In order to measure the critical current of the prototype cable, an inductive method is developed: the cable is closed in a low resistance loop forming the secondary coil of a transformer, while the 6 Tesla background magnet serves as the primary.
The critical current...
Bilfinger NOELL GmbH is the contractor of GSI for main SIS100 magnets.
The production of the 111 SIS100 Dipoles is completed and all dipoles are delivered to GSI. We will give a summary on the production of these magnets highlighting some of the major challenges. Production workflow, individual production steps and results from quality measurements at Bilfinger Noell are presented.
In the...
As known, the cold-rolled thin Nb-Ti tapes demonstrates very strong anisotropy of pinning force regarding rolling direction and external magnetic field because of dense anisotropic grain boundary structure. This leads in particular to form of “fish-tail” feature in low-field area of magnetization loops in inclined field due to competition of self-field and small external field in media with...
Abstract:
Dynamo-type high-temperature superconducting (HTS) flux pump has been verified to be a practical method for the charge of HTS magnet, due to its simple structure and low cost. The nonlinear properties of HTS stator which is influenced by its substrate magnetism, play an important role on the charging performance of the dynamo-type HTS flux pump. Generally, there are three kinds...
Abstract: High temperature superconducting (HTS) maglev, which uses the magnetic flux pinning effect to realize the suspension and guidance, has attracted wide attention in the field of transportation due to its advantages of self-stabilizing suspension, high efficiency, and energy saving. As the connection components between the bogie and car body, and the transmission components of traction...
New generation accelerators, such as future circular collider (FCC), require superconducting dipole magnets with non-copper $J_c$ of 1500 A/mm$^2$ at 16 T, 4.2 K. Nb$_3$Sn is the only proven superconductor with large-scale industrial production. Still, present Nb$_3$Sn wires can not meet the required conditions, and improvement in the fabrication is needed. Kobe Steel Ltd. has developed...
Bi-2212/Ag round wires are promising conductor candidates for the development of high-field magnets up to 25 T. With very high upper critical magnetic field and critical current density, Cable-In-Conduit Conductor (CICC) comprised of Bi-2212/Ag superconducting wires is under designing for the central solenoid coils of the China Fusion Engineering Test Reactor (CFETER). The current degradation...
With recent progress of fabrication technology of long length and high critical current high temperature superconducting (HTS) wires, the application of HTS wires to the windings in rotational machines becomes feasible. In most current research and development of HTS rotational machines such as large scale wind turbine generators and ship propulsion motors, the HTS wires are applied only to...
GdBa2Cu3Oy (GdBCO) coated conductors is one of the most promising candidates due to its high critical temperature over 90 K and high critical current density of the order of 1 106 A/cm2 at 77 K. The presences of a-axis-oriented grains has been known to cause the worsening current characteristics, so that it is important to investigate the formation mechanism of a-axis-oriented grains. In...
Typical Cable In Conduit (CIC) typed Nb3Sn conductor applied for the fusion magnets are manufactured by twisting multiple Nb3Sn strands based on the current-carrying specification. Jc degradation by the cyclic loading in the CIC conductors was confirmed. This is caused by the Nb3Sn filament breakage by applying the huge electromagnetic force (i.e. transverse compressive load). Therefore, the...
Simply- and quickly-fabricated low-resistive joints between various high-temperature superconducting (HTS) tapes are needed for some cases in high-temperature superconducting (HTS) magnets such as nuclear magnetic resonance (NMR) magnets, nuclear fusion magnets, and so on. We have developed pressure welding with indium foil inserted between the joint surfaces at room temperature or with a...
In order to increase the diversity of people's travel mode and fill the blank of the travel speed between the aircraft (900km/h) and the high-speed train (300km/h), the high-temperature superconductor magnetic levitation train still needs to be developed. The conventional magnetic rail used for levitation mainly adopts the isometric magnets. Advanced solution uses Halbach Array, which can...
High-temperature superconducting (HTS) maglev has good application prospects due to its passive stability. There are many researches on the levitation characteristics of a single bulk HTS in applied magnetic field. However, the bulks are usually arranged in an array in practical applications. In addition, experiments proved that levitation force and guidance force of the system with two bulks...
A long-term scientific project such as the Large Hadron Collider (LHC) at CERN must undergo periodic, preventive and corrective maintenance of electronic components along their lifetime. Components that typically require replacement are the aluminium electrolytic capacitors. More than 36’000 units, rated 500 V and 4.7 mF are installed in the protection systems of the high field LHC...
The long time thermal stability and radiation resistance of micro composite wires based on Cu-Nb alloy intended for use in devices with high neutron fluxes has been studied. We have demonstrated that for a given niobium content in the alloy (6%), it is possible to keep the ultimate tensile strength higher than 375 MPa after exposed to annealing vacuum treatment at 450 °C up to 3000...
As the so-called no-insulation (NI) HTS winding technique or its variations have expanded their applications beyond laboratory magnets, technical concerns on lifecycle such as lifetime, fatigue, long-term performance variation have become an important and timely imperative issue for the actual application of an HTS magnet to real-world systems. This paper reports long-term time-varying...
Though low resistance joint is important technology for persistent current operation of HTS magnet system, superconducting joints of REBCO wires require direct epitaxial growth between REBCO surfaces that can only occur in high temperature procedure. On the other hand, at 4.2 K operation, even conventional solder spliced joints of coated conductors should have quite low joint resistance if low...
Electron-beam additive manufacturing, or electron-beam melting (EBM) is a type of additive manufacturing, or 3D printing for metal parts. The raw material (metal powder or wire) is placed under a vacuum and fused together from heating by an electron beam. This technique is distinct from selective laser sintering as the raw material fuses having completely melted.
For industries such as...
In this work, we summarize the results of an experimental campaign of inductive and transport measurements aimed at the evaluation of the electromechanical performances of a 0.85 mm diameter RRP® wire relevant for the HiLumi LHC project. SEM micrographs have been used to evaluate the sub-element diameter and Cu/non-Cu ratio, whereas the chemical composition across the sub-element sections has...
This study analyzes the output characteristics of a 100-turn non-rotational-type metal insulation (MI) coil and a no-insulation (NI) coil installed inside a 1-MW armature with external fluctuating magnetic fields. Experiments were conducted to investigate the change of state and output performance of the superconducting coils based on the fluctuating magnetic field prior to the development of...
The effect of the magnetic flux trapping in normal-phase fractal clusters on critical currents in percolative HTS composites is studied. The normal-phase clusters are united by the common trapped flux and surrounded by the filling superconducting phase. The superconducting phase fraction is above the percolation threshold so there is a superconducting percolation cluster which is carrying a...
The cross-section design of cos $\theta$ superconducting magnets is historically developed in a two-step process: initially, the coil geometry is defined on the basis of magnetic optimizations; then, the structure is designed around the coil. The first step searches for the best coil cross-section maximizing the magnetic field, margin, field quality and conductor efficiency. The latter step...
PERC is a novel experiment in the field of low energy particle physics under construction at the FRM II in Garching, Germany. The project aims to investigate angular correlations and energy spectra in the β-decay of free cold neutrons.
PERC consists of 13 superconducting solenoid coils. In a 6 m section of the 8 m long decay solenoid e- & p+ form neutron decay are accumulated. At the end of...
China Fusion Engineering Test Reactor (CFETR), a new tokamak device, is under concept design based on the experience of Experimental Advanced Superconducting Tokamak (EAST) and ITER. Research and development of TF coil for CFETR is carried out by ASIPP. TF coil is winding by Cable in-Conduit Conductor (CICC). Main manufacturing process of CICC includes welding of jacket, draw lead, winding and...
The performance of accelerator magnets is strongly relying on the dielectric strength given by the electrical and mechanical robustness of the insulation system. This is in particular relevant for the current development of high field superconducting Nb3Sn magnets with their insulation system made from fibre reinforced resin. During the assembly and operation, this insulation system is exposed...
The new Nb3Sn superconducting magnet system for a 45 GHz electron cyclotron resonance (ECR) ion source is under developing in the Institute of Modern Physics (IMP). The sextupole coil, which is wound by a single Nb3Sn wire, is indeed a great technical challenge. Because of the complicated technology process and the stress sensitivity of the full-length Nb3Sn sextupole coil, a sextupole...
Nb3Al superconducting wires have high critical current and low strain sensitivity of the superconducting properties. Therefore, many Nb3Al wires were developed for accelerator or fusion magnets. In this study, critical current and mechanical properties of various Nb3Al wires were investigated. Some kinds of rapid heating, quenching and transformation (RHQT) processed Nb3Al wires were prepared....
The Fourth-generation ECR (FECR) ion source Nb3Sn Superconducting Magnet is being developed by Institute of modern physics, Chinese Academy of Sciences. In order to reduce the risk of development, a representative prototype is designed. The FECR prototype consists of two Nb3Sn solenoid coils and six Nb3Sn sextupole coils, This paper reports on the assembly process and cool-down to cryogenic...