POLYPHASE ELECTRONICALLY COMMUTATED RELUCTANCE MOTOR

A motor structure and energization scheme provides a high efficiency electronically commutated reluctance motor that is characterized by less iron losses than conventional switched reluctance motors. Preferably, the motor operates without the reversal of the flow of flux in the member of the motor supporting the motor windings (e.g., the stator). Also, the flux switching frequency in the first member is reduced and preferably minimized. By eliminating flux reversals and minimizing the flux switching frequency, the electronically commutated reluctance motor is operable over a wide range of speeds with improved efficiency. Structurally, first and second members of the motor are mounted for relative movement. The first member includes unevenly spaced teeth, whereas the second member includes evenly spaced teeth. The teeth of the first member are grouped into pairs separated by a space related to the even spacing of the teeth on the second member. Adjacent pairs of teeth on the first member are separated by a spacing which is not equal to the spacing between the teeth of a pair. To provide for relative movement of the first and second members, each pair of teeth on the first member are polarized to form poles of opposite polarity such that a magnetic circuit is formed joining the two adjacent teeth of the pair.