Single Parametric Control of Cascade Brushless DC Motor Drive

Abstract

The proportional plus integral (PI) control is the most widely used algorithm to regulate the armature current and speed of Brushless DC motors in cascade motor drive control systems. However, even when effective tuning methods are employed to satisfy the desired performance, the output overshoot is of higher values. In this paper the PI current controller is replaced with a proportional-integral-derivative (PID) controller to eliminate the overshoot in current loop and then the overshoot in speed loop. Methods of computing PID current controller parameters are derived using Internal Model Control as a function of motor parameters. The transfer function of overall closed loop current is used to determine PI speed controller parameters. Simulation results show the robustness and the effectiveness of the proposed method.