Modelling of skew using the flux-MMF diagram

The flux-MMF diagram has recently been used effectively to predict electromagnetic and cogging torque ripple in different motor types. This paper describes a simple and elegant method, based on this technique, for predicting the effect of skew on torque ripple in permanent magnet motors. While the fact that skewing minimizes torque ripple is well established, the paper clearly brings out the difference in the extent of minimization in the case of electromagnetic as well as cogging torque ripple. Further, it shows that the effect of skew on these two types of torque ripple is quite independent of each other.