WB-3-4

Development of high temperature superconducting CORC® magnets, CICC, and low loss joints for fusion applications

16:30-16:45　28/11/2023

*Jeremy Weissab, Danko van der Laanab, Kyle Radcliffa, Steven Allenc, Jack Greenwoodc, Julian Holtc, Ian Alsworthc, Peter Danielsc, Frank Schoofsc, Shailendra Chouhanc, Stuart Ellisc, Tim Mulderd, Herman ten Kated, Arend Nijhuisd, Yuhu Zhaie, Daniel Davisf, Ulf Trociewitzf, Youngjae Kimf, and David Larbalestierf
a. Advanced Conductor Technologies LLC, Boulder, Colorado 80301, U.S.A
b. Department of Physics, University of Colorado, Boulder, Colorado, U.S.A
c. United Kingdom Atomic Energy Authority, Oxfordshire, U.K.
d. University of Twente, Enschede, the Netherlands
e. Princeton Plasma Physics Laboratory, Princeton, NJ, U.S.A
f. National High Magnetic Field Laboratory, Florida State University, Tallahassee, Florida, U.S.A
Abstract Body

High-temperature superconductors (HTS) are promising candidates for use in the high-field magnets needed in compact fusion reactors. Advanced Conductor Technologies is developing HTS Conductor on Round Core (CORC®) cables wound from ReBa2Cu3O7-xcoated tapes for use in high-field magnet applications. Recent test results will be presented on an insert solenoid tested at high current ramp-rates relevant for Ohmic heating coils (up to 5 kA/s) and in a background field of 12 T. For larger fusion magnets, such as toroidal field coils operating at currents beyond 60 kA, cable-in-conduit conductor (CICC) configurations are required. The use of HTS enables prospects for demountable superconducting fusion magnets that would allow easier access to the fusion experiment for maintenance but require practical, low-resistance, joints. CICC pairs consisting of six CORC® cables were tested at currents up to 10 kA while the demountable joint between them experienced a background magnetic field of up to 8 T. The total loop resistance of two HTS samples, including their terminations and joint, was about 4 nΩ at 4 K in self-field, with the contact resistance between the copper pressure joint being less than 1 nΩ. Results will also be presented on the development of two new CICCs with distributed support for the CORC® cables to be tested at the Sultan test facility at currents up to 80 kA in background fields up to 11 T. These tests prove the feasibility of producing HTS coils, CICC, and remountable low resistance joints for applications in future fusion machines.

References

J. D. Weiss et al., “Performance of low-loss demountable joints between CORC® cable-in-conduit-conductors at magnetic fields up to 8 T developed for fusion magnets,” Supercond. Sci. Technol., vol. 36, no. 8, p. 085002, Jun. 2023, doi: 10.1088/1361-6668/acdc59.
Y. Zhai et al. HTS Cable Conductor for Compact Fusion Tokamak Solenoids IEEE Transactions on Applied Superconductivity, vol. 32, no. 6, pp. 1–5, Sep. 2022, doi: 10.1109/TASC.2022.3167343.

Acknowledgment

This work was in part supported by the US Department of Energy under agreement numbers DE-SC0013723, DE-SC0014009, DE-SC0018125 and DE-SC0019934