Research on Speed Control Strategy of Double Closed-Loop Brushless DC Motor Based on Nonlinear Active Disturbance Rejection Control

Aiming at the external and internal disturbances in a permanent magnet brushless DC motor servo system operation, a double closed-loop brushless DC motor (BLDCM) speed control based on nonlinear active disturbance rejection control (NLADRC) is adopted. The NLADRC is designed in the speed and current loops, respectively; the tracking-differentiator realizes the fast-tracking of the command signal without overshoot, the estimation value is obtained by constructing the second-order dilated state observer for real-time observation of the disturbances and compensated, and the nonlinear state error feedback control law generates the error integral signals. The simulation outcomes indicate that, compared to the linear active disturbance rejection control strategy, the nonlinear approach provides the system with a quicker response, enhanced disturbance rejection, and improved robustness against variations in load and motor speed.