HYBRID HIGH T-C SUPERCONDUCTING MAGNETIC BEARINGS FOR FLYWHEEL ENERGY-STORAGE SYSTEMS

Low energy-loss hybrid superconducting magnetic bearing using YBCO (12 3) high temperature superconductors (HTS) coupled with permanent magne ts have been designed and employed to construct a prototype flywheel e nergy storage system. The rotor weights about 19 kg. The hybrid HTS ma gnetic bearing uses permanent magnets to provide the levitating force and superconductors to stabilize the inherently unstable magnet-magnet interactions. The hybrid bearings are brought into action under conve nient zero-cooled conditions. This work aimed at explicating the conce pts and illustrating the feasibility of such hybrid HTS bearing for lo w energy-loss flywheel energy storage applications. Measured results f or various bearing characteristics and a preliminary spin-down test in a crude vacuum of 7 x 10(-3) Torr are presented.