Low friction in high temperature superconductor bearings

Abstract

A study of drag in rotating permanent magnet/high temperature superconductor magnetic bearings is reported. The effects of magnet asymmetry, atmospheric resistance, and eddy currents are discussed. One of the bearings achieved a rotational speed of 200 000 RPM and a low speed coefficient of friction of 8.1×10−6, values that have technological significance for flywheel energy storage.