Intelligent tuning of commutation for maximum torque capability of a switched reluctance motor

Since the winding current and inductance profiles of a switched reluctance motor (SRM) are far from ideal, its torque generating characteristics are quite ambiguous and difficult to optimize quantitatively. In this paper, the intelligent commutation tuning control to improve the torque generating performance of an SRM is presented. First, the effect of the commutation instant on the torque characteristics of a singly excited SRM is observed. Then accordingly, an intelligent method of commutation tuning is developed to improve the torque generating capability. In making the tuning, the minimization of the motor drawn line current is employed as a performance index to equivalently yield maximum torque per ampere (TPA). Finally, the circuit implementation of the developed tuning scheme is carried out. The appropriate commutation makes the motor draw minimum current under any load condition. It follows that the motor conversion efficiency is also improved. In addition, owing to the increased torque generating capability, the tracking and regulation speed control performances are also improved. Some experimental results are provided to demonstrate the effectiveness of the proposed control scheme.