Title :
AC loss measurement of 46 kA-13T Nb3Sn conductor for ITER
Author :
Takahashi, Yoshikazu ; Matsui, Kunihiro ; Nishii, Kenji ; Koizumi, Norikiyo ; Nunoya, Yoshihiko ; Isono, Takaaki ; Ando, Toshinari ; Tsuji, Hiroshi ; Murase, Satoru ; Shimamoto, Susumu
Author_Institution :
JAERI, Ibaraki, Japan
fDate :
3/1/2001 12:00:00 AM
Abstract :
AC losses of Nb3Sn conductor samples with various void fractions for the ITER Central Solenoid Model Coil (CSMC) were measured by using calorimetric and magnetization techniques. The CSMC is designed to generate the magnetic field of 13 T at the operating current of 46 kA. The conductor consists of the multi-stage cable, having 1152 Nb3Sn strands, and Incoloy 908 square jacket with circular hole. The strands are coated by chrome plating with 2 μm layer. The last sub-cables are wrapped with Inconel tape, having high electric resistivity, to reduce the coupling current loss. The optimum void fraction for pulse coils is obtained from the relation between the coupling time constant and the void fraction. It is indicated that the sub-cable wrapping is very effective in limiting the coupling current between the sub-cables, as expected. The AC losses of the CS Insert were measured in various operating modes. From these obtained results, the validity of conductor design is demonstrated
Keywords :
calorimetry; chromium alloys; fusion reactor design; loss measurement; magnetisation; multifilamentary superconductors; nickel alloys; niobium alloys; superconducting cables; superconducting coils; superconducting magnets; tin alloys; 13 T; 2 mum; 46 kA; AC loss measurement; CS Insert; Central Solenoid Model Coil; ITER; Incoloy 908 square jacket; Inconel tape; Nb3Sn; Nb3Sn conductor; calorimetric technique; chrome plating; coupling current loss reduction; coupling time constant; high electric resistivity; magnetic field generation; magnetization technique; multi-stage cable; optimum void fraction; pulse coils; void fraction; Cable shielding; Coils; Conductors; Electric resistance; Loss measurement; Magnetic field measurement; Magnetization; Niobium; Solenoids; Tin;
Journal_Title :
Applied Superconductivity, IEEE Transactions on
