Analysis and control of seven-phase permanent-magnet bearingless motor with single set of half-coiled winding

In this paper, a seven-phase inset-type permanent magnetic bearingless motor is proposed with characters as the treble frequency suspension force compensation and elimination of the affection of the third plane to the suspension plane. The winding configuration and harmonic distribution are presented. Then, the analysis formulations of inductance and suspension force of the proposed motor are presented and verified by Finite Element Analysis (FEA). Furthermore, the control system is proposed based on the derived voltage model, torque model and suspension force model with the rotor eccentricity being considered. Finally, the Simulink simulation is provided on a prototype motor to verify the validity of the analysis.