1.5 kA Bi-2223 HTS current leads for SMES magnets

1.5 kA class Bi-2223 HTS current leads for superconducting magnetic energy storage (SMES) magnets were fabricated and tested. The HTS leads were composed of Bi-2223/Ag-1 at%Au tapes fabricated by PIT process and stainless steel former and they were connected to conventional gas-cooled copper leads, Using a calorimetric method, heat input to the liquid helium through the HTS leads was estimated to be 0.395 W/lead when the warm end part's temperature was 65 K, which was slightly greater than the calculated value of 0.35 W/lead. The measured critical current of the HTS leads was about 1.6 kA when the warm end part's temperature was 80 K. This measured value was well consistent with computed values.