A new bearing structure for a single-axis controlled repulsive type magnetic bearing with motor function

This paper reports novel magnetic bearing structures with the function of a bearingless motor (BeLM) and a repulsive type magnetic bearing (RTMB). The structures consist of circular arc permanent magnets for field poles and cylindrical permanent magnets for magnetic bearings. Two types of permanent magnet configurations suitable for an ultra high-speed motor are proposed in this paper. From measurement results of magnetic flux density distributions, it was verified that a magnetic pole composition using Halbach array leads to good coexistence of both BeLM and RTMB.