Electromagnetic Considerations for a Six-Phase Switched Reluctance Motor Driven by a Three-Phase Inverter

The switched reluctance machine (SRM) offers advantages over other topologies, but low torque density, high torque ripple, and use of a nonstandard power converter are limitations. This paper develops a drive configuration, which facilitates the operation of a six-phase SRM using a standard three-phase inverter in order to address these limitations. The focus of the paper is an investigation of electromagnetic design aspects of two candidate SRM topologies in this six-phase context for a pure electric or hybrid electric vehicle-type application. Advances are made in the understanding of the electromagnetic design of suitable SRMs, and the conventional SRM is demonstrated as the preferred topology through parametric and finite-element analysis (FEA) design studies with reference to a given specification. Laboratory test results for a prototype machine are presented in verification of the machine design and demonstration of this drive concept as a high-torque-density candidate suitable for electric vehicle applications.