核融合炉用60 kA高温超伝導電流リードの開発と試験結果

抄録

JAERI has been developing a large-capacity high-temperature superconductor (HTS) current lead for fusion application, and succeeded in fabricating and testing a 60 kA HTS current lead satisfying ITER requirements. Targets of performance are 1/10 heat leak and 1/3 electric power consumption for the cryogenic system as compared use with a conventional lead. To achieve these targets, selection of HTS sheath material, optimization of the Cu part, reduction of joule heat at the joint between HTS and Cu parts and improvement of heat transfer between the HTS and stainless-steel tube were investigated. The 60 kA HTS current lead developed satisfied the design conditions and nearly achieved the targets. Adoption of the HTS current lead reduces the total electric power consumption of the ITER's cryogenic system by 13%.