Development and Performance Comparison of Single-Stator and Dual-Stator Doubly Salient Permanent Magnet Machines

In this article, the doubly salient permanent magnet machines (DSPMMs) with single-stator (SS) and dual-stator (DS) configurations are developed and investigated. In order to make full use of the internal space of the motor, the winding and permanent magnets (PMs) are placed on the inner stator for the DS-DSPMM. The structures of the two machines are presented, and the operation principles are explained by winding flux linkage characteristic and air-gap field modulation theory. A comparative study between the SS-DSPMM and DS-DSPMM with dual-armature and hybrid-excited modes is established. It can be obtained that the DS-DSPMM with hybrid-excited mode exhibits the largest output torque, smallest torque ripple, and best flux regulation capability. The suitable distributions of the excitation and armature currents are important for the electromagnetic performance of the DS-DSPMM, which can achieve the maximum output torque or the minimum torque ripple. The finite-element results and electromagnetic performances are validated by different experiments on the fabricated prototypes.