A new variable reluctance motor utilizing an auxiliary commutation winding

A novel concept for solving the current commutation and energy circulation problems in conventional variable reluctance motors (VRMs) is presented. The concept enables the energy stored in the magnetic field to be retained and utilized within the motor instead of being returned to the source. A novel VRM and two companion converters are proposed and described. The operating principles of the motor and the converters are presented. Simulation results based on a linear model are presented to demonstrate the degree of improvement that can be realized. By retaining and utilizing the field energy within the machine by utilizing commutation windings, the new motors are free from the current commutation problem and excitation penalty normally associated with VRMs. Consequently, compared with conventional VRMs the new motors have (1) better turn-off and turn-on performance; (2) higher speed capacity; (3) higher torque density; and (4) potential for higher efficiency