Research and Development of Fully Superconducting Motors for Liquid-hydrogen Transfer Pumps

Abstract

The research and development conducted regarding fully superconducting motors for liquid-hydrogen transfer pumps using MgB₂ monofilamentary wires are gathered into this paper. Synchronous rotation without slip can be realized using squirrelcage-type rotor windings composed of quasi-superconducting loops soldered between MgB₂ wires, thereby enabling superconducting motors with low loss and high efficiency to be achieved. The use of MgB₂ wires for stator windings also enables the primary winding loss to be reduced drastically compared to conventional copper winding. The transfer of liquid hydrogen from a metal cryostat containing the fabricated MgB₂ motor to a glass Dewar vessel for visual monitoring is demonstrated successfully.