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

Abstract

The Switched Reluctance Machine (SRM) offers advantages over other topologies, but low torque density, high torque ripple, and use of a non-standard 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 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.

Effects of Winding Connection on Performance of a Six-Phase Switched Reluctance Machine

“…As has previously been described [28], the N-S polarities of the single-phase connection give rise to long flux paths via the full stator and rotor core ( Fig. 3 (a)), whilst the N-N polarities of the single-phase connection give rise to shorter flux paths which link adjacent teeth ( Fig.…”

“…Alternative winding connection types were investigated for this drive and a symmetric winding pattern was proposed whereby phase windings are unconventionally connected with opposing polarities, giving rise to significant phase interaction [27]. This drive has demonstrated high torque density and is proving to be a strong Xu Deng, Barrie Mecrow, Member, IEEE, Richard Martin, and Shady Gadoue Effect of Winding Connection on Performance of a Six-Phase Switched Reluctance Machine S candidate in electric vehicles applications [28].…”

Design and comparative evaluation of converter topologies for six‐phase switched reluctance motor drives

“…This converter combines many of the advantages of the candidates described in Section 2, requiring only one diode, switch, and power connection per phase having no additional energy storage element, and facilitating some form of conventional SRM current control. Compared to the full‐bridge converter in [20], diodes placed in series with each phase are no longer required. Since the six‐phase windings are connected in a ring, this arrangement is subsequently named a ‘ring converter’.…”

“…A method for driving a six‐phase SRM from a three‐phase inverter has recently been proposed [20]; an unconventional winding scheme was investigated in this context, and the resulting drive demonstrated low torque ripple and high torque density, in addition to a number of substantial benefits arising from the use of a standard converter. In particular, it was shown how additional steering diodes rectified the sinusoidal, three‐phase supply to a six‐phase unipolar group suitable for a six‐phase SRM.…”

Bidirectional multiport solar‐assisted SRM drive for pure electric vehicle applications with versatile driving and autonomous charging capabilities

“…A tri‐port converter is discussed in [29] for power flow among battery PV and SRM to achieve various driving and charging modes. In [30], electromagnetic design consideration of a six‐phase SRM fed by the standard three‐phase inverter is discussed. A modular power converter formed using a dual and a six‐pack IGBT module for a three‐phase SRM is presented in [31] where phase windings are Y‐connected and bipolar excited.…”