Design And Research Of Servo Control System Of Hydraulic Screw Down For Rolling Plate

Accuracy of gauge is an important indicator of the steel rolling, rolling gauge control is one of the core in technology areas. Automatic gauge control is a kind of technology to control gauge of the central part of the rolled sheet, it becomes indispensable technical equipment for hot rolling strip mill and cold rolling mill in recent years. As an important development in rolling direction, precision rolling technology proposes higher demands on control accuracy for the hydraulic AGC system.This paper outlines the theory of hot-rolled plate, including plate rolling mill of the reduction process and methods. In the second chapter, depth research of the hydraulic servo control system was proposed, I described the composition and development of electro-hydraulic servo control system and analyzed the character of valve controls asymmetric hydraulic cylinder, established the model of valve controls cylinder of two-way movement (including a servo control system for the linear model and nonlinear model).To enhance the level of control plate rolling and gauge accuracy, a number of intelligent algorithms have been gradually applied to the steel field of study. Detailed review and study of differential evolution algorithm will further proposed. Differential evolution algorithm is a heuristic-based group differences in random search method, it has simple principle, fewer control parameters and good robustness. There are many differential evolution algorithm for differential strategies, in which the more representative and better are DE/rand/1 and DE/best/1.Another task of this paper is making differential evolution method used to PID controller based on ITAE optimal adjustment law, achieves PID parameters line setting. This method was applied to establish a good hydraulic AGC system, and perform a simulation to compare the model linear and nonlinear response characteristics, and compares the results of differential evolution tuning PID control parameters and conventional method tuning PID parameters, the simulation results and data demonstrate the feasibility and control effects. The transition process of ITAE regulating law has the characteristics of fast and stable, and it can be well used in the practical engineering application, compared to the PID regulating law which is common used in current industry, ITAE has better performance indicators, is seen as the best SISO control system and adaptive control system with the best performance.