Pole-Shape Optimization of a Switched-Reluctance Motor for Torque Ripple Reduction

Switched-reluctance motors produce acoustic noise and vibration caused by torque ripple. Applications of these motors where silent operation is desirable, such as in home appliances, has, thus, been limited. This paper describes a proposal for a new stator pole face having a nonuniform air-gap and a pole shoe attached to the lateral face of the rotor pole. These additions minimize the undesired torque ripple. The effects of each design parameter were investigated using a time-stepping finite-element method. The parameters were optimized by utilizing response surface method (RSM) combined with (1 + 1) evolution strategy. It has been shown, through numerical tests, that the optimized shape gives higher average torque and drastically reduced torque ripple