Design of toroidal field coil for the JT-60 superconducting tokamak

• Published in: IEEE transactions on applied superconductivity Vol. 13; no. 2; pp. 1480 - 1483
• Main Authors: Tsuchiya, K., Kizu, K., Miura, Y.M., Ando, T., Isono, T., Matsui, K., Koizumi, N., Matsukawa, M., Sakasai, A., Ishida, S.
• Format: Journal Article Conference Proceeding
• Language: English
• Published: New York, NY IEEE 01.06.2003; Institute of Electrical and Electronics Engineers; The Institute of Electrical and Electronics Engineers, Inc. (IEEE)
• Subjects: Applied sciences; Coiling; Conductors; Conductors (devices); Electrical engineering. Electrical power engineering; Electromagnets; Exact sciences and technology; Field coils; Finite element analysis; Insulation; Insulators; Niobium; Plasmas; Stress; Stress analysis; Stresses; Superconducting cables; Superconducting coils; Superconducting magnets; Superconductivity; Tokamak devices; Tokamaks; Toroidal magnetic fields; Various equipment and components; Zooming; Performance evaluation; Tokamak; Plasma; Stress analysis; Insulator; Dielectric materials; System design; Charge injection device; react and wind technique; Toroidal field; TF coil; Pipe cable; Sensitivity; Nb3Al; Poloidal field; JT-60SC; Magnetic energy
• ISSN: 1051-8223; 1558-2515
• DOI: 10.1109/TASC.2003.812748

The modification of JT-60 is programmed to be a superconducting tokamak (JT-60SC) that has superconducting toroidal field (TF) and poloidal field coils. The TF coil system, which consists of 18 D-shaped coils, makes the field of 3.8 T at plasma center (R = 2.8 m). The stored magnetic energy in total is 1.7 GJ. A squared Nb/sub 3/Al cable-in-conduit (CIC) conductor using SS316LN jacket allows us to fabricate the TFC by a react-and-wind (R&W) technique because of low strain sensitivity of Nb/sub 3/Al J/sub c/ characteristic. In order to support TF coils against the centering force, the inboard side of the TF coil case is wedged. Shear panels and keys between the TF coils are placed against the overturning force induced by poloidal fields. Stress analysis of the TF coil support structure was carried out. In the case of the maximum displacement caused by overturning force, the maximum stress was lower than the allowable stress of SS316LN at 4 K. The stress analysis of insulator and conduit at the inboard side of the TF coil with zooming model was also carried out. It is clear from zooming analysis that the stresses of conduit and insulator are within the allowable stress. Regarding a progress of R&D, demonstration of R&W technique using a D-shaped double layer coil with the full-scale CIC conductor is planned in this year in order to confirm its designed performance.