HIGH-GRADE CONTROL OF SWITCHED RELUCTANCE MACHINES

This paper formulates the objectives associated with high-grade torque control of switched reluctance motors (SRM's), Low torque ripple is a natural outcome of high bandwidth torque control, Smooth torque opera tion is only uniquely defined together with a secondary objective, suc h as maximum efficiency, maximum torque-speed capability, maximum powe r factor, etc., as the SRM does not enjoy the inherent distribution be tween phases that characterizes ac drives, By introduction of the flux -angle parameter, operation at any point between maximum torque-curren t ratio and maximum torque-flux ratio is possible, A systematic approa ch to waveform design is developed and is evaluated using both simulat ion and experimental testing of an SRM servo-drive system, This approa ch, which can be regarded as a functional equivalent of ac vector cont rol, starts from machine parameters and gives smooth torque operation with maximized torque-speed range and/or efficiency, Excellent dynamic performance is obtained for speed and position control, together with optimized low torque ripple operation.