Analysis and simulation of the high-speed torque performance of brushless DC motor drives

A simulation model for the performance prediction of brushless DC drives is used to investigate the high-speed torque performance for a motor switched by a PWM inverter. The solution is given for both 120° and 180° conduction angles of inverter operation, with provision for selecting the advance commutation angle. The influence of the more important drive parameters on high-speed performance is described. The paper also presents two simplified analytical approaches for obtaining the optimum phase-advance angle in the high-speed ranges. The merit of these methods, compared with trial-and-error based on simulation, is described