A Novel Parallel Motor Winding Structure for Bearingless Motors

A novel winding structure without separated suspension winding has been proposed for bearingless motors. The proposed winding structure basically has two parallel paths in three-phase motor windings. One three-phase winding path has a neutral point in general, but another three-phase winding path is connected to a suspension inverter, which injects currents for suspension force generation. Additional suspension windings are not needed in the stator slots, because the two parallel path windings are used for both torque and suspension force generation. In the proposed winding structure, speed induced voltages are cancelled each other so that no speed induced voltage is induced at suspension terminals.