The application of high voltage superconducting apparatuses is considered as one of the most promising countermeasures against the increased power consumption. In order to ensure the electrical safety of high voltage superconducting apparatuses such as superconducting transformers and superconducting cables, the electrical insulation design should be conducted considering aging...
Electrical insulation of superconducting magnets represents one of the most critical aspects in the manufacturing and operation of these devices. In tokamaks, for instance, the use of superconducting magnets is highly recommended since superconductivity constitutes an enabling technology for fusion plasmas, nonetheless, their capability in withstanding off-normal loading conditions was never...
Solid insulation materials for superconducting applications are required to be robust in terms of both mechanical and electrical performance. The electrical insulation performance of gaseous medium is inferior to that of liquid medium. Also, the characteristics of creepage discharge is inferior to those of penetration breakdown. Therefore, electrical breakdown of a high voltage superconducting...
Thus far, RE123 coated conductors have revealed their promising potential for high field generating materials. On the other hand, RE123 bulks grown by the melt-solidification method, which can trap much higher magnetic field than permanent magnets, have been opening new superconducting applications, such as flywheels, magnetic separation, drug delivery, levitating mixer and compact NMR. ...
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...
As part of the Large Hadron Collider High Luminosity upgrade (HL-LHC) project, 11 tesla Nb3Sn dipole magnets will replace some of the existing 8.33 T Nb-Ti LHC main dipole magnets. The 11 T dipole coils are mechanically loaded through a removable pole wedge. The force exerted on the Ti6Al4V pole wedge is transmitted onto the coils via tangential sliding of the wedge on the coil shims and...
The Central Solenoid (CS) is the backbone of the ITER magnet system. It consists of six independent coils held together by a vertical pre-compression structure that must react tensile loads and provide sufficient preload to maintain coil-to-coil contact during all stages of plasma operation. The CS pre-compression system includes three different types of tie plates, lower and upper key blocks,...
Institute of Plasma Physics Chinese Academy of Science (ASIPP) is designing and manufacturing a Central Solenoid Mode Coil (CSMC) to develop the manufacturing process for China Fusion Engineering Test Reactor (CFETR) CS coil. The hybrid magnet structure is employed for the CSMC, and modified 316LN stainless steel is selected as the jacket material for the Nb3Sn cable in conduit conductor,...
The ITER Cable-In-Conduit Conductor (CICC) used in the superconducting magnet system consists of a cable made of 300 to 1440 strands housed in a stainless steel jacket. China needs to provide six different kinds of conductor. The jackets are circular, square, as well as circle-in-square jackets made of either a very low carbon AISI 316LN and AISI 316L grade stainless steels. The mechanical...
The high strength conductors used in pulsed magnets in the US National High Magnetic Field Laboratory (MagLab) are manufactured from Cu matrix composites. One of the composites is made from particle reinforced Cu. The fabrication of these composite conductors requires high deformation strain, which creates high densities of dislocations and reduced particle spacing. Both mechanical strength...
The ITER Feeder is an important sub-system which transmits the electrical power, conveys the cryogenic coolant and carries the instrumentation wires to the ITER Tokamak magnet system. In the Feeder, all the high voltage (HV) potential components, including the high temperature superconducting current leads, the superconducting busbars, and the busbar joints, need to be insulated with solid...
Cu-6wt.%Ag micro-composites were fabricated via casting and accumulative bundling and drawing (ADB) process. The evolution of microstructure and crystal orientation during the compositing process was observed. The mechanical properties and conductivity characteristics of the materials were investigated. And the mechanism for the mechanical properties was discussed.
A novel methodology is proposed for the structural optimization of the inner-leg cross-section of Toroidal Field (TF) coils of DEMO fusion reactor to achieve significant improvements in the structural response of the component. The original Winding Pack (WP) configuration, used as starting point of the optimization process, despite being compliant in terms of the electro-magnetic behavior,...
Superconducting properties of CeO2 doped and undoped YBCO superconductors were evaluated to investigate the effect of pinning center on the magnetization properties. The variation △M with doping was maximum for 5 wt% doping and decrease with further doping. The result indicates that △M is propotional to the number of magnetic flux lines passing through the sample. The CeO2 was converted to...
The superconducting magnets for the LHC High Luminosity upgrade (HL-LHC) are built using Nb3Sn technology, which implies a reaction heat treatment when the conductor is at final shape. During the reaction heat treatment the Nb3Sn coil is surrounded by a fixture that restricts the coil volume changes. The knowledge of the evolution of the thermo-mechanical properties of the coil materials and...
A comprehensive study of upper critical (Hc2) and irreversibility magnetic fields (Hirr) in (Ba0.6K0.4)Fe2As2, Ba(Fe0.95Ni0.05)2As2, Ba(Fe0.94Ni0.06)2As2, Ba(Fe0.92Co0.08)2As2, and Ba(Fe0.92Co0.09)2As2 polycrystalline bulk pnictide superconductors for different average grain sizes was made in pulsed fields at the Los Alamos National Laboratory. The magnetic field-temperature (Hc2-T) phase...
Zylon fibres are used at the National High Magnetic Field Laboratory for structural reinforcement of high field pulse magnet coils. We have studied the fibre properties with respect to the aging effect and light resistance. The high modulus and strength values were associated to the crystalline and texture. Long time exposure to lab-light was found to decay the crystallinity, increase...