Two Mathematical Models of Five-Phase High Speed Permanent Magnet bearingless Slice Motor

Most bearingless motors run at a relatively low speed because of the high iron loss problem. Considering that a slotless structure is beneficial to high speed, this paper deduces two mathematical models based on this existent structure. The first model is for traditional control and the second one is for fault-tolerant control. In the process of derivation, the concept of superposition is introduced to calculate the flux density in the air gap. At last, finite element analysis is done to verify the model.