High temperature superconducting demonstrator transformer: design considerations and first test results

The paper highlights main features of a 10 kVA single-phase high temperature superconducting (HTS) demonstrator transformer built recently at the University of Southampton. One winding is made of BPSCCO-2223 tape with bulk critical current density of 22A/mm/sup 2/ at 77 K. Flux diverters have been used to reduce the radial component of leakage flux density in the HTS tape. Initial test results are shown with particular emphasis on measurements of ac losses.