ITER-CS インサート･コイル試験

Abstract

The Japan Atomic Energy Agency (JAEA) is procuring conductors for the ITER central solenoid (CS). To evaluate the superconducting performance of the CS conductor, a test coil “CS insert” was fabricated and tested at the CS model coil test facility in JAEA Naka. The CS insert is a single-layer, nine-turn solenoid using a piece of the actual CS conductor. The test was performed in 2015, and its duration was five months including initial cool-down and final warm-up. At the beginning, the nominal conditions of 40 kA - 13 T and 45.1 kA - 12.5 T were achieved. The change in current-sharing temperature (Tcs) was then measured during 16,000 cycles of electromagnetic force and three cycles of warm-up to room temperature and cool-down. There was no apparent degradation of Tcs observed. The variation in Tcs resulting from conductor strain in the longitudinal direction was also measured using direct and reverse charges. Quenching behavior was measured using an inductive heater installed at the middle point of the CS insert. From the tests, a database to estimate the performance of the CS conductor for the actual ITER CS was established.