SUPERCONDUCTING HOMOPOLAR MOTOR AND CONDUCTOR DEVELOPMENT

The U.S. Navy has been developing superconducting homopolar motors for ship applications since 1969; a successful at-sea demonstration of th e first motor, using NbTi wire for the magnet, was achieved in the ear ly 1980s. Recently, this same motor was used as a test bed to demonstr ate progress in high-critical-temperature superconducting magnet techn ology using bismuth-strontium-calcium-copper-oxide (BSCCO) compounds. In the fall of 1995, this motor achieved a performance of 124 kW opera ting at a temperature of 4.2 K and 91 kW while operating at 28 K. Futu re tests ave scheduled using new magnets with conductors of both the 2 223 and the 2212 BSCCO phases. This article describes the advantages o f superconducting propulsion and recent progress in the development of BSCCO conductors for use in Navy power systems.