학술논문
The SPARC Toroidal Field Model Coil Program
Document Type
Periodical
Author
Hartwig, Z.S.; Vieira, R.F.; Dunn, D.; Golfinopoulos, T.; LaBombard, B.; Lammi, C.J.; Michael, P.C.; Agabian, S.; Arsenault, D.; Barnett, R.; Barry, M.; Bartoszek, L.; Beck, W.K.; Bellofatto, D.; Brunner, D.; Burke, W.; Burrows, J.; Byford, W.; Cauley, C.; Chamberlain, S.; Chavarria, D.; Cheng, J.; Chicarello, J.; Diep, V.; Dombrowski, E.; Doody, J.; Doos, R.; Eberlin, B.; Estrada, J.; Fry, V.; Fulton, M.; Garberg, S.; Granetz, R.; Greenberg, A.; Greenwald, M.; Heller, S.; Hubbard, A.E.; Ihloff, E.; Irby, J.H.; Iverson, M.; Jardin, P.; Korsun, D.; Kuznetsov, S.; Lane-Walsh, S.; Landry, R.; Lations, R.; Leccacorvi, R.; Levine, M.; Mackay, G.; Metcalfe, K.; Moazeni, K.; Mota, J.; Mouratidis, T.; Mumgaard, R.; Muncks, J.; Murray, R.A.; Nash, D.; Nottingham, B.; O'Shea, C.; Pfeiffer, A.T.; Pierson, S.Z.; Purdy, C.; Radovinsky, A.; Ravikumar, D.K.; Reyes, V.; Riva, N.; Rosati, R.; Rowell, M.; Salazar, E.E.; Santoro, F.; Sattarov, A.; Saunders, W.; Schweiger, P.; Schweiger, S.; Shepard, M.; Shiraiwa, S.; Silveira, M.; Snowman, F.; Sorbom, B.N.; Stahle, P.; Stevens, K.; Stillerman, J.; Tammana, D.; Toland, T.L.; Tracey, D.; Turcotte, R.; Uppalapati, K.; Vernacchia, M.; Vidal, C.; Voirin, E.; Warner, A.; Watterson, A.; Whyte, D.G.; Wilcox, S.; Wolf, M.; Wood, B.; Zhou, L.; Zhukovsky, A.
Source
IEEE Transactions on Applied Superconductivity IEEE Trans. Appl. Supercond. Applied Superconductivity, IEEE Transactions on. PP(99):1-18
Subject
Language
ISSN
1051-8223
1558-2515
2378-7074
1558-2515
2378-7074
Abstract
The SPARC Toroidal Field Model Coil (TFMC) Program was a three-year effort between 2018 and 2021 that developed novel Rare Earth Barium Copper Oxide (REBCO) superconductor technologies and then successfully utilized these technologies to design, build, and test a first-in-class, high-field (∼20 T), representative-scale (∼3 m) superconducting toroidal field (TF) coil. The program was executed jointly by the MIT Plasma Science and Fusion Center (PSFC) and Commonwealth Fusion Systems (CFS) as a technology enabler of the superconducting high-field pathway to fusion energy, and, in particular, as a risk retirement program for the no insulation (NI) TF magnet in the SPARC net-energy fusion tokamak. The TFMC achieved its programmatic goal of experimentally demonstrating a large-scale high-field REBCO magnet, achieving 20.1 T peak field-on-conductor with 40.5 kA of terminal current, 815 kN/m of Lorentz loading on the REBCO stacks, and almost 1 GPa of mechanical stress accommodated by the structural case. Fifteen internal demountable pancake-to-pancake joints operated in the 0.5 to 2.0 nΩ range at 20 K and in magnetic fields up to 12 T. The DC and AC electromagnetic performance of the magnet predicted by new advances in high-fidelity computational models was confirmed in two test campaigns while the parallel, single-pass, pressure-vessel style coolant scheme capable of large heat removal was validated. In the test facility, a feeder system composed of REBCO current leads and cables was experimentally qualified up to 50 kA, and a liquid-free cryocooler-based helium cryogenic system provided 600 W of cooling power at 20 K with mass flow rates up to 70 g/s at a maximum design pressure of 2 MPa for the test campaigns. Finally, the feasibility of using passive, self-protection against a quench in a fusion-scale NI TF coil was experimentally assessed. While the TFMC was intentionally not optimized for quench resiliency – and suffered localized thermal damage in response to an intentional open-circuit quench at 31.5 kA terminal current – the extensive data and validated models that it produced represent a critical step towards this important objective.