Characteristic evaluation of mechanical jointed HTS cable for remountable HTS magnets

Remountable HTS magnets are suggested for as a method to reduce the construction and maintenance costs of a fusion reactor. Butt joints of BSCCO 2223 HTS cable, where cross-sections of the cable are jointed mechanically, have been researched for the new concept. In a previous study, stress distribution on the joint surface in the butt joint was evaluated by numerical analysis. The result showed the importance of obtaining homogeneous stress distribution on the joint surface to reduce the joint resistance. In this study, therefore, the relations between the joint resistance and the stress distribution inside the HTS cable is evaluated for several loading systems by structural analysis and experiment. Based on the result, an efficient loading system is suggested, which can achieve the uniform stress distribution on the joint surface and can avoid the stress concentration.