Design of toroidal field coil for the JT-60 superconducting tokamak
K. Tsuchiya, K. Kizu, Y. M. Miura, T. Ando, H. Nakajima, T. Isono, K. Matsui, N. Koizumi, M. Matsukawa, A. Sakasai, S. Ishida
Japan Atomic Energy Research Institute, Naka Fusion Research Establishment
Abstract.
The modification of JT-60 is planned to a superconducting tokamak (JT-60SC) that has superconducting toroidal field (TF) and poloidal field coils. The TF coil (TFC) system, which consists of 18 D-shaped coils (6.0m x 3.9m), makes the field of 3.8T at plasma center (R=2.8m). The stored magnetic energy in total is 1.7GJ. A squared Nb3Al cable-in-conduit conductor (CICC) using SS316LN jacket allows us to fabricate the TFC by a react-and-wind (R&W) technique because of low strain sensitivity of Nb3Al strands. In order to confirm the designed performance of CICC, a demonstration of R&W technique using D-shape sample with the full-scale CICC is planned in this year. The inboard side of the TF coil case is wedged against the centering force. Shear panels and keys between the TF coils are placed against the overturning force induced by poloidal fields. Stress analysis of the TFC support structure was carried out. In a case of the maximum displacement induced by overturning force, the maximum stress was lower than the stress limit of SS316LN at 4K. The stress analysis of insulator and conduit at the inboard side of the TFC with zooming model was also carried out.