On Disturbance Rejection Control of Servo System Based on the Improved Disturbance Observer

Abstract

Requirements of the servo system are keeping rising with the development of technology, industrial production and other areas. Traditional proportional integral derivative (PID) control cannot meet the control requirements of servo system when there is external disturbance and measurement noise in the system. In this paper, the mechanism and method of using improved disturbance observer (DOB) to eliminate the disturbance and noise are studied and applied to the control of speed servo system. Based on the traditional PID controller, simulations on MATLAB/Simulink and tests on Quanser semi-physical experiment platform are performed for the PID controller with and without improved DOB. Simulation and experimental results show that the improved DOB overcomes the problem of noise amplification in classical DOB and can effectively suppress external disturbance and noise at the same time.