CURRENT LEADS - FIRST APPLICATIONS OF HIGH-TC SUPERCONDUCTORS FOR POWER DEVICES

The integration of high Tc superconductors into the structure of curre nt leads allows thermal and electrical losses to be reduced substantia lly. As a first step towards such hybrid leads for AC power applicatio ns in the kA range, DC demonstration current leads have been developed achieving 2 kA/20 kV. To this end, precursor powders and bulk parts t ogether with their manufacturing processes have been developed and inv estigated for four different material options, i.e. sintered YBCO 123, melt textured YBCO 123, melt cast BSCCO 2212 and sintered BPSCCO 2223 . The most suitable physical data and technical performance were found for the Bi-based compounds. Thus, a reduction of the 4 K heat load up to 1/10 of conventional values was achieved in demonstration current leads operated at 1 - 2 kA DC. (R&D project of an industrial consortiu m in the frame of the Brite/Euram Programme)