Research On Control Strategy Of Electro-Hydraulic Servo Control For Strip Deviation Rectification

When the strip is up to one hundred meters or longer continuous production line delivery, the strip is inevitable to deviation, because the strip status is not good, strip tension uneven, the roller surface quality defects and equipment installation accuracy is poor. Too much deviation will damage equipment and reduce the quality of the strip-off, even stop production, which causing great economic losses to producer.There are many measures to rectify the strip, but the strip of electro-hydraulic servo control system is the most widely used and better control. The system is composed of controller, servo valves, hydraulic cylinders, displacement sensors, photoelectric sensors and other components. When the photoelectric sensor detects the strip deviation signal and passes it to the controller, servo valve which controll hydraulic cylinder driven coiler. Then the strip is correction to the specified location, and the motion detector detects whether the feedback position reaches the designated locationStrip correcting electro-hydraulic servo system is a typical valve-controlled cylinder system. Since the electro-hydraulic servo system has the character such as nonlinear and time-varying, and traditional PID controller is adjusted for a long time with a low control accuracy. To solve these problems in this paper, I studied strip correcting control strategy by MATLAB/Simulink simulation platform software to build correction system model. Fuzzy control is particularly suitable for the control of nonlinear systems without knowing the exact mathematical model of the control system. Therefore, this article is designed strip electro-hydraulic correcting fuzzy controller. However, fuzzy control has its own flaws, which controlled system may generate steady-state error. This article is designed strip correcting fuzzy PID control strategy combining PID control and fuzzy contorl with their respective advantages. By simulation, analysis and comparison controlling the effectiveness of different control strategies, it proves that fuzzy PID control strategy is much better.Finally, This article is designed based on chip computer control system correction simulation test device and tested. The results showed that a higher correction device precision control, lower equipment costs and up to the standard of engineering applications.