Cogging torque suppression in a permanent-magnet flux-switching integrated-starter-generator

摘要

Permanent-magnet flux-switching (PMFS) machine offers high torque density,impressive flux-weakening capability and mechanical ruggedness because of itsdistinctive configuration, and is potentially suitable for the application inautomotive integrated-starter-generators (ISGs). However, the PMFS machinegenerally exhibits higher cogging torque compared with other machines commonlyused in ISGs. Minimisation of the cogging torque in the PMFS machine for itsutility in ISGs is therefore of particular importance. Four rotor topologies areproposed here as cost-effective means to suppress the cogging torque of a PMFSISG. The validity of the proposed techniques has been confirmed by both two-dimensional finite-element analysis and experimental results. Moreover, theinfluence on the back electromagnetic force by these techniques is alsoinvestigated.