Switched reluctance motor with 2-phase excitation

A new excitation strategy for a switched reluctance motor (SRM) is described and tested. This scheme excites two phases of an SRM simultaneously, which is similar to the two-phase excitation method of a step motor. In this scheme, the torque is produced by mutual inductances as well as by self inductances. The abrupt change of phase excitation produces mechanical stresses and results in torque ripple and noise. The acoustic noise is reduced remarkably through the sequential phase excitation in the two-phase excitation. This is because the scheme reduces abrupt changes in excitation levels by distributed, balanced excitation and free-wheeling during commutation. The operational principle and a characteristic comparison to that of the conventional SRM show that this novel excitation scheme has some advantages including torque ripple and noise reduction as well as simple inverter topology.