The Research Of Hydraulic Control System In Straightening Machine Base On Fuzzy PID

With the rapid development of our country's economy, the demands of high-quality and high-strength steel plates are rising fast in various sectors. In order to guarantee the steel plate's high performance, straightening machine has become the essential equipment in the modern iron-steel corporation. It plays an important role in quality control of the plate. In the past decades, the leveling technology is already very mature. At present, the study of the Straightening machine is concentrated on the hydraulic adjustment installment. The adjustment installment of straightening machine with advanced control algorithm can reach much better effect of control.This dissertation is mainly study on the hydraulic servo-control system of adjustment installment in straightening machine, and emphatically makes a study of control system of hydraulic adjustment installment at electro-hydraulic servo-control. In this dissertation, it analyzes various parts' mathematical model, and it has established the simplified model of constant-force control system of adjustment installment, and analyze the dynamic characteristic of the control system in straightening machine. Then the conventional PID controller, fuzzy controller and fuzzy self-tuning PID controller of adjustment installment in straightening machine are simulated by using fuzzy-logic toolbox and Simulink in MATLAB. The experimental results illustrate that the conventional PID controller is used in the system, overshoot and response time always cannot achieve the specification. When uses the fuzzy controller, there are not obviously optimization compare with conventional PID, and the system presented the steady-state error. When uses the fuzzy self-tuning PID controller, the overshoot, response time and error can meet the requirements, but the system performance remains to be further enhancing. According to the former response curve of established model, we selected the advanced fuzzy self-tuning PID controller which based on artificial immune algorithm to enhance the system performance. The experiment indicated that this algorithm obviously optimized the system parameters of the impact of changes in the system.After studying and analyzing simulated result, this subject simulation is more successful when doing in the laboratory. While guaranteeing precision of control system, advanced control algorithm improves the system capacity of resisting disturbance, and the dynamic performance of system has much better improvement compared with the classic method.