Modelling of high torque density switched reluctance motors with mutual coupling

Abstract

High torque density switched reluctance motors (SRM) have a stator yoke thickness as small as possible. This can lead to strong mutual coupling between the flux paths of the motor phases and thus an isolated modelling of each motor phase of the SRM is imprecise. In this paper a method is suggested which models the resulting motor torque and current dynamics directly from the flux linkages with no need of inductances. That allows an easy calculation from measurement or simulation results. The model is validated by 2D finite element analysis. With a proper method to measure the flux linkage characteristics it is sufficient to calculate half of an electrical period to get all information to model the system behavior, even for both long and short flux path phase connection sequences.