SR motor produces high torque ripple compared to other machines. This is caused by the non-linear and discrete nature of the torque production mechanism. The total torque developed in a SR motor is the sum of the torque generated by each of the independently controlled stator phases. Torque ripple is significant at the commutation instants when the torque production is being transferred from one phase to another.
Various methods have been proposed to eliminate the torque ripple that a SR motor produces. An analytical modelling approach to find the optimum phase current is most commonly used. Several other methods have used a neural network to model the non-linear characteristics of SR motor in order to solve the torque ripple problem. The following discussion will divide the methods between these two categories. The analytical modelling approach can be categorised further into explicit and implicit torque profile methods. Figure 14 provides an overview of the torque ripple minimisation methods which will be discussed here.
