Starting system for salient-poled-rotor electric motor

Abstract

A starting system and method for starting a salient-poled-rotor electric motor having a stator with a plurality of spaced salient poles, a plurality of field coils of unchanging polarity, and a plurality of armature coils, wherein each field coil of the plurality of field coils at least partially overlaps an armature coil of the plurality of armature coils, and wherein variable excitement of the armature coils alternately creates a magnetic pole force in every other pole of the plurality of spaced salient poles of the stator. In such motors, the stator has a first position, wherein the rotor is in stasis with respect to the stator and torque between the rotor and the stator is substantially minimized, and a second position, wherein torque between the rotor and the stator is substantially maximized. A drive circuit provides current to the field coils and the armature coils. A start circuit is provided for regulating the drive circuit to vibrate the rotor to the second position. A current source is connectable to the drive circuit for variably exciting the armature coils to produce substantially continuous rotation of the rotor. A switch is provided for electrically engaging the start circuit with the drive circuit while the rotor moves from the first position to the second position, and for electrically engaging the current source with the drive circuit when the rotor reaches the second position.