Development of integrated system of remountable superconducting magnet, first wall and liquid blanket for prototype reactor.

为了降低超导磁体的建造和维护成本，提出了一种新型的超导磁体可拆卸式超导磁体系统。本研究的目的是通过阐明高温超导电缆对接接头的基本特性，证明高温超导电缆在低于几百安培的液氮温度下对对接接头接头部位发热的鲁棒性，论证可拆卸高温超导磁铁的可行性。首先，对高温超导胶带对接接头进行了基础研究，明确了其基本性能。实验结果表明，随着输运电流的增大，接头电阻增大。数值分析表明，接头电阻对输运电流的依赖是由于接触面附近高温超导细丝的退化引起的。数值分析也证实了高温超导细丝的相对位置对接头性能没有影响。事实表明，接触条件是决定接头性能的主要因素。由此，阐明了高温超导电缆对接接头的一些基本性能。此外，还认为镀金属是保护和改善接触面状况的有效方法。在基础研究的基础上，对叠合高温超导电缆对接性能进行了实验评价。首先证实了镀金属对保护和改善接触面状况是有效的。此外，没有发生热猝灭和临界电流的降低。这说明高温超导电缆在低于几百安培的液氮温度下，对对接接头接头部位的发热具有稳健性。在本研究的最后，制作了可拆卸式高温超导磁体的原型，并对其性能进行了评估，为今后可拆卸式高温超导磁体的发展提出了建议。结果表明，与铜磁体相比，可拆卸式高温超导磁体在能量损失方面具有优势。少

Remountable HTS magnet system was proposed as a new design of fusion reactor to reduce both construction and maintenance costs in term of superconducting magnet. Objective of this study is feasibility demonstration of remountable HTS magnet by clarifying basic properties in butt joint of HTS cable and proving robustness of HTS cable against heat generation at jointing parts in butt joint at liquid nitrogen temperature below several hundreds amperes.Firstly, fundamental studies on the butt joint of HTS tape were performed to clarify the basic properties. Experimental results showed that joint resistance increased when transport current increased. According to numerical analysis, the dependence of joint resistance on transport current is caused by degradation of HTS filament near the contact surface. It was also confirmed that relative position of HTS filament does not affect joint performance by the numerical analysis. The fact indicates that contact condition is dominant to decide the … More joint performance. From mentioned above, some basic properties in the butt joint of HTS cable was clarified. In addition, it was considered that metal-plating is predicted to be effective to protect and improve contact surface condition. Based on the fundamental studies, the butt joint performance of laminated HTS cable was evaluated experimentally. At first, it was confirmed that metal-plating was effective to protect and improve contact surface condition. Furthermore, thermal quench and decrease of critical current did not occur. This fact shows that HTS cable has robustness against heat generation at jointing parts in butt joint at liquid nitrogen temperature below several hundreds amperes. At the end of this study, prototype of the remountable HTS magnet was fabricated and its performance was evaluated to suggest future tasks of development of the remountable HTS magnet. And it was indicated that the remountable HTS magnet has an advantage in term of energy loss compared to copper magnet. Less