Development program of a 60 kA current lead using high temperature superconductors

Abstract

Abstruct -The use of high temperature superconductors in current leads to reduce the refrigerator power consumption has been investigated in the last few years by many groups. Potential candidates are Y-123 and Bi-2212 bulk material as well as Bi-2223 tapes sheathed with an Ag/Au alloy. In the frame of the European Fusion Technology Programme, FZK Karlsruhe and CRPP Villigen have started a development program for design and construction of a 60 kA current lead for the ITER Toroidal Field Coils. The task composes of three parts: material selection based on test results of 1 kA current leads, construction and test of 10 and 20 kA leads using the selected HTSC material giving proof of the modularity and scale-ability of the design, and finally construction and test of a 60 kA current lead which will replace an existing conventional lead in the superconducting coil test facility TOSKA at FZK. The paper describes the status of the development program. Experimental results o f the first step and a first approach of the realisation of the 10 kA HTSC lead are given.