Optimization of Stator Design in a Consequent-Pole Type Bearingless Motor Considering Magnetic Suspension Characteristics

In this paper, a design optimization method for a consequent-pole bearingless motor is presented. This produces stable magnetic suspension under motor torque generation. The suspension force reduction and direction error, which can be caused by torque generation, are limited in the proposed designs. In the optimization routine, the number of suspension and torque winding turns and air-gap length are carefully assessed. Three stators are constructed for experimental verification. The amplitude and direction errors for the suspension force are found to be within acceptable ranges and the operation of the magnetic suspension is acceptable