Construction of the Stator Installed in the Superconducting Magnetic Bearings for a 10kWh Flywheel

Abstract We fabricated a superconducting magnetic bearing module consisting of a stator of epoxy resin impregnated YBaCuO bulks and a rotor of NdFeB permanent magnet circuits. We obtained levitation force density of 10.5 N/cm 2 at 67 K and rotation loss per levitation force of 2.5 mW/N at 77 K. The rotation loss was reduced by the decrease of magnetic field inhomogeneity in the circular direction along the ring shape permanent magnet of the rotor. Based on these results we constructed a stator consisting of five modules and installed in the form of superconducting magnetic bearing for a 10 kWh class flywheel energy storage test system.