ITER-CSインサート・コイルにおける誘導加熱ヒーターを用いた安定性試験

For the stable operation of the Central Solenoid (CS) coil of the ITER without quenching, it is important to know the threshold of allowable external heating energy the CS conductor can be subjected to during operation. To evaluate the minimum quench energy of the CS conductor for the ITER, an inductive heating test was performed during the CS Insert Coil (CSIC) test campaign. A 59-turn inductive heater installed on the central turn of the CSIC was used to apply the heat energy. The heating energy from the inductive heater was calibrated by calorimetry using short conductor samples with inductive heater windings and a resistive heater. A series of inductive heating tests was performed while applying a 45.1 kA current and 12.5 T backup field on the CSIC. The alternating current (AC) applied for the inductive heater was 1,000 Hz in 40 ms, and the amplitude of the AC was varied until a quench occurred. As the result, it was obtained that the minimum quench energy for the CSIC heated by eddy current was 0.23 J/cm3 without including the joule heating energy of the heater itself