Turn-off angle control of switched reluctance motors for optimum torque output

A new analytical concept is proposed to determine the turn-off angle for optimum torque output. It is based on the simplified voltage equation of the motor terminal. Simulation results based on a linear motor model are presented to demonstrate the influence of turn-off angle on torque output. The concept enables the online calculation of the optimal turn-off angle. It just requires the knowledge of some state variables within the control loop and some fixed drive parameters. A decrease in torque ripple and subsequently a decrease in acoustic noise is the result. The concept is applicable to the full wave mode and the chopping mode as well