Current sharing temperature of the ITER-TF insert

Nunoya, Yoshihiko; Sugimoto, Makoto; Isono, Takaaki; Hamada, Kazuya; Matsui, Kunihiro; Okuno, Kiyoshi; CS Model Coil Test Group

Vurrent sharing temperature (Tcs) measurement of ITER toroidal field insert was performed. The coil is NbSn superconducting coil and was installed inside of the ITER CS model coil as a backup field coil. Relation between the voltage of individual strand composing TF insert conductor and the measured voltage using the taps on the jacket is investigated and the evaluation method for Tcs measurement was established. The obtained results shows that there was discrepancy between the expected value from the strand data and the measured value which is lower by about 1.2K. Some discrepancy was already observed just after cool down of the insert before energizing.