Design And Application Of Anti-windup Compensator

Actuator saturation is a very common phenomenon in the control system.Normally,during the design of linear control systems,the control signal is assumed to be infinitely input to the controlled object.However,actuators would have a limit of the input signal in practical control systems for various reasons.If the output of the controller has exceeded the limit,the closed loop performance of the system will have a sharp drop and even lead to instability of the system.In order to get better performance of the system,anti-windup compensator can adjust the controller which is working under the saturation condition.So the research and design of anti-windup compensator has far-reaching significance.The main research content of this article is:(1)On the basis of summarizing the existing literature on the researches of saturation systems,the conventional anti-windup compensator has a poor performance,so this paper will use robust optimization theory to analyze the linear system under actuators saturation,designing double loop AW(anti-windup)compensator on the basis of the original controller,which uses different level of compensation signal to compesator the correspond level of saturated control signal and the design process for double AW gains is proposed.(2)Double loop AW is applied to the back-calculation and tracking AW method which is a commonly used method in dealing with the saturation problem of PI controller,then fuzzy self-tuning method is raised to tune the AW gain for the compensator when different reference signals are put into the system.(3)A new modified three filters internal model control(IMC)scheme is proposed to handle the system which has the saturation and disturbance problem simultaneously.This scheme accomplish decouple of anti-windup,interference and tracking compensation.To verify the effectiveness of these methods,by using Matlab/Simulink and Quanser SRV02 servo system simulation platform,the double loop AW and three filters IMC are simulated respectively,the simulation results show that the double loop AW has better performance than traditional AW,three filters internal model control structure can suppress the interference and saturation at the same time.