Simulation And Optimization Studies Of Dynamic Characteristic Of Hydraulic AGC System Based On AMESim

Automatic Gauge Control(referred as AGC) is one of the two key technologies in strip rolling field.Automatic gauge control technology will directly affect the quality of sheet and strip.The strip thickness accuracy of plate and strip steel is an important quality index, not only to the savings during production process, but also be of great significance on downstream industries.Hydraulic AGC system is an important branch of the thickness control system.A typical hydraulic automatic control system consists of hydraulic systems, control systems, mechanical systems and electrical system components. Automatic gauge control technology combines the knowledge of many subject areas. Although the gauge control technology has been applied for many years in China's steel industry and similar industries, but there are still many problems in the actual application of production. Because of the thickness of strip be affected by hydraulic servo systems, control systems, process conditions and transient changes of raw materials in the common areas.Such as the impact of the realization of the control system more difficult.Therefore it is necessary to simulate the rolling process and hydraulic AGC system to findout the principles of these factors on thickness accuracy, and thus improve the dynamic characteristics of hydraulic AGC system and the thickness accuracy.This paper for the simulation and optimization of the dynamic characteristics of hydraulic AGC system, mainly for the following work:â‘ Conducting hydraulic AGC system before the simulation and optimization. Systematic discussed the process of strip rolling and the basic theory of automatic gauge control and control methods. Made summary of the main factors affecting the thickness of the plate and strip in the rolling process and the discipline of actual variation of the exit thickness.Analyzed several basic AGC system structure and its control principle based on different ways of the thickness of the rolling process;â‘¡Derived and set up the basic equations of electro-hydraulic servo valve,the basic equation of hydraulic cylinder and load of the roll system, the transfer function of servo amplifier, oil pipeline and the sensors and other dynamic components in the hydraulic AGC system based on analyed the theory and operational mechanism of hydraulic AGC system.And then set up a dynamic model of hydraulic AGC system;â‘¢Constructed hydraulic AGC system simulation model using the integrated modeling and simulation platform-AMESim.The simulation of hydraulic AGC system was done using PID controller.Analyed the main factors which impact the system's dynamics and control accuracy.After the steady control effect of system been achived,the optimization test of hydraulic system was done using NLPQL and genetic algorithm. Verified by simulation test, the control accuracy of hydraulic AGC system based on NLPQL algorithm and genetic algorithm has been improved.The simulation and optimization results will partly be used in 1780mm sheet production line in hot-rolle factory of Chongqing Iron and Steel Group Co., Ltd. Model data for reference presented to help the installation process and commissioning the diagnosis of the mill's hydraulic AGC system.