Sliding Mode Control based on Disturbance Observer for Servo System

Servo system are nonlinear uncertain system which are hard to control by traditional method, sliding mode control (SMC) is a special nonlinear control method which have quick response, insensitive to parameters variation and disturbance, online identification for plants are not needed, its very suitable for servo system control, but in reality usage, the chattering reduction and elimination is key problem in SMC. In order to realize chattering reduction and elimination, the sliding mode control with disturbance observer was applied into this paper, the definition of sliding mode control was presented and on the basis of the description of servo system, the sliding mode controller was designed, by Lyapnouv theorem the stability analyzed and the simulation shows the methods is effective and can applied into servo system control.