Robust Switching Control of the Direct-Drive Servo Control Systems Based on Disturbance Observer for Switching Gain Reduction

Due to the existence of external disturbance which affects the systems' robustness and stability, a robust sliding mode switching controller with disturbance observer method has been developed for the switching systems of the direct-drive servo control systems, which can eliminate the chatter and reduce the switching gain of the switching systems completely or alleviate it greatly. According to the Lyapunov stability method and the periodically switching law, the resulting closed-loop switched system is robustly stable such that all the signals in the resulting closed-loop switched system of the direct-drive servo control systems keep bounded and the sliding surface of the switching system can be well reached. Finally, the presented switching control scheme is easy to implement and simulation results illustrate the good control performance.