Pioneering superconducting magnets in large tokamaks: Evaluation after 16 years of operating experience in tore supra

摘要

The toroidal field (TF) system of TORE SUPRA (TS) is superconducting. After 16 years of operation it is possible to give an overview of the experience gained on a large superconducting system integrated in a large Tokamak. Quantitative data will be given, about the TF system for the cryogenic system and for the magnet system as well, concerning the number of plasmas shots and the availability of the machine. The origin and the number of breakdowns or incidents will be described, with emphasis on cryogenics and associated repairs and changes on the system components along the time. As concerns the behaviour during operation, the fast safety discharges (FSD) in operation are of particular interest for the Tokamak operation, as they interrupt it for a significant time of the order of 1 h. This aspect is particularly documented. The approach followed to decrease the number of these FSD will be reported and explained. The TORE SUPRA Tokamak was the first important application of superconductivity in plasma physics on a large scale. Overall, despite the differences in design and size, the accumulated experience over 16 years of operation is a useful tool to prepare the manufacture and the operation of the ITER magnets.