Transient performance based design optimization of PM brushless DC motor drive speed controller

Using standard integral criteria for optimization of speed controller parameters in an electric motor drive result in relatively high overshoot in speed response. Besides that, the speed controller's integral time constant is much higher than maximum drive time constant, which is unfavorable for load torque compensation, in this paper the speed controller parameters of a permanent magnet (PM) brushless direct current (DC) motor drive are obtained in terms of the overshoot in speed response. A dependence of overshoot in speed on speed controller's gain coefficient and integral time constant is derived and graphically presented for easier adoption of the derived results in industrial and research laboratory settings. It is further demonstrated that faster and better load torque compensation is achieved with smaller values of integral time constant and larger values of speed controller gain coefficient A desired speed overshoot is achieved by adding a filter at drive input. Responses on both reference and load torque variations of PM brushless DC motor drive validates the proposed design approach. The results are obtained using Matlab program package for simulation and optimization of the PM brushless DC motor drive.