Research On The Principle Of Nonlinear PID Auto Disturbance Rejection Control

PID controller with a simple structure which has been widely used in industrial control is easy to use.But for some nonlinear characteristics,which significantly influence and interference of large controlled object,there is a contradiction between rapidity and overshoot,anti-interference ability and other shortcomings.Therefore,for the purpose of PID control in-depth analysis and research,this article is to improve the performance of PID control and present a self-learning method of nonlinear PID control immunity,specifically includes the following sections:(1)The research status and development trend of domestic and PID control.Proceed from the basic principle of PID control,presentation and analysis of several common digital PID control method and PID controller the most important parameter tuning methods were introduced and summarized.(2)Since the PID control with time-varying nonlinear controlled system has strong features such as disturbance,cannot meet the performance requirements of their control.In this paper,strong immunity and robustness of ADRC various components have conducted in-depth analysis and simulation,and put forward the improvement direction.(3)A nonlinear PID control method is put forward for a self-immunity study.According to the nonlinear combination of power function in the expansion of the state observer function causes the chattering problem in the system,using a nonlinear smooth function instead of the power of non-linear combination of functions,not only completely eliminates the chattering phenomenon,but also conducive to the expansion of the state that the observation accuracy.As non-linear error feedback law is complex,difficult to understand and has many parameters.According to the PID control process,proportional,integral and differential,three gain parameters is law of error variation curves,proposes the thought which transforms traditional linear PID control law to the control of nonlinear PID control law,and using self-learning algorithm for real-time adjustment of three nonlinear gain function of gain coefficient,implement nonlinear PID self-learning control.Building self-learning control nonlinear PID immunity system architecture,which consists of tracking differentiator and extended state observer nonlinear smooth function of self-learning and nonlinear PID controller.Comparing the simulation shows that the self-study of nonlinear PID control method is effective immunity and superiority.