Relation Between Stator Core Shape and Torque Ripple for SPM Motor

This paper presents relation between stator core shape and torque ripple for a surface-mounted permanent magnet (SPM) motor. An SPM motor with different stator core shapes is analyzed to clarify the influence of tooth width on torque ripple. In order to consider detailed magnetic properties of non-oriented electromagnetic steel sheet used for a stator core, a motor is analyzed by using 2-D finite element method which introduced an E&S (Enokizono & Soda) model. Furthermore, torque ripple reduction is attempted by chamfering the corner of tooth-tips. As a result, it is shown that tooth-end width and tooth-tip shape are very important for not only torque increase but torque ripple reduction.