Direct Torque Control of Brushless DC Motor

Due to the good performance of brushless motor, its application is widespread. Brushless DC motor has following advantages that are low interference, low noise, high efficiency and so on, so it was widely used in industrial and control field. But DC motor has larger current commutation torque ripple, greatly reduce their reliability and stability. This design using direct torque control strategy to reduce torque ripple, and compares the control results of PI controller with direct torque control method. In the process of regulating motor’s speed ，When adopts PI controller here has great overshoot and start time of speed is long than direct torque control, current pulse obviously severe than direct torque control. The simulation results show that overall effect of direct torque control is superior than double closed loop control. It fully explains that the control strategy in this paper is effective.