A performance of single phase switched reluctance motor having both radial and axial air gap

Abstract

A switched reluctance motor (SRM) has been developed with merits such as the low cost and reliability. Recently, its application has been expanded from industrial to home appliance use. The inverter of the SRM is more robust than that of induction or brushless DC(BLDC) motors, but still its drive is comparatively expensive for home appliances. To drive a conventional three- or four-phase SRM, 6 to 8 power switches are required when an asymmetric bridge inverter is employed. Generally, more than 50% of the cost for the SRM drive is allocated to power devices and gate drives. This paper proposes a single-phase SRM that has both radial and axial air gaps. The stator and rotor were stacked with two types of stampings that have different diameters. This configuration is very effective to increase align inductance (Lmax). The high value of Lmax increases the motor efficiency and power density. The proposed single-phase SRM (Claw SRM) can be driven by only two power switches. To show the validity of the proposed idea, an analysis using the finite element method (FEM) and experimental works are carried out. The proposed SPSRM can be driven with high efficiency and can be made compactly and inexpensively because of the high value of align inductance and reduced number of switches. For the comparison, the authors used the same stator for three-phase and single-phase designs, and slightly different stators and rotors for the proposed single-phase SRM (Claw SRM).