Research On The Control System Of Oil Extraction Joint Station Based On PLC

Due to simple structure,steady function and reliable and convenient operation,PID controller is widely used in process control and dynamic control.But there are many defects in the routine PID adjustment.such as strong nonlinearity,fast time-varying uncertainty and strong disturbance,The most important thing is the parameter adjustment of PID controller.People are making great effort to realize the automatic adjustment on line for PID parameter to make the control process into a best state all the time.This paper studies the self-tuning PID controllers.Compared with the conventional PID,it has many advantages: it can restrain the overshoot and increase the stability of the system;design the less parameters in adjustment possess powerful adaptability;It can be accumulated on the process information,is a kind of adjustable controller.The recursive least square method is used to derive the parameters of the self-tuning PID controller,and the recursive least squares method with forgetting factor is given according to the characteristics of the system parameters.In MATLAB environment,we simulate the system of Self-tuning PID controller,and study the adaptability,when PID controller parameter changes.The results show that when adopting the self-revised PID controller,the system can adapt the complex working conditions and the controller can select the PID parameters automatically.Moreover,it has solved the difficult problem of setting large delay experimental boiler system PID parameters.