Gauge Control System Of Hot-rolling Based On MCU

With the rapid development of modern industrial technology and production processautomation, the high dimensional accuracy of rolled products are increasingly needed by thevarious departments of the national economy. Thickness accuracy is one of the maindimensional quality indicators in measuring the Slab-strip steel and the main goal of improvingproduct quality. AGC is an important method to improve the thickness accuracy of theSlab-strip steel, its purpose is to eliminate the influence of various factors change in the processof rolling to rolling thickness by adjusting the pressure and the tension and the rolling speed, soas to achieve its target thickness. Over the years, how to improve the accuracy of plate stripgeometry size has been the focus of domestic and international metallurgical industry.From the analysis of the causes and thickness variation of the fluctuations in the thicknessof the plate strip the law of the basic form of automatic gauge control and its control principle, adetailed derivation of the basic mathematical model of the dynamic components of thehydraulic AGC system, and to determine the system equivalent model. Due to thecomplex of the rolling process of hydraulic AGC system with a complex, nonlinear, large timedelay, time-varying characteristics, generally difficult to establishprecise object model.Although the traditional PID controller has a simple structure, convenient operation, highreliability, robustness,etc. Demanding, but the accuracy of the controlled object mathematicalmodel of to deal with complex nonlinear system is difficult to obtain the desired controleffect.The fuzzy control is a natural language description of the control strategy using fuzzy settheory to human experts into the algorithmic language for the computer can accept. Thedesign does not require the establishment of the controlled objeit model, especially for difficultto obtain in the model, the dynamic characteristics is not easy to grasp, themoreserious non-linear system. However, due to the fuzzy controller dose not have the integral, thusthe steady-state accuracy is not high.For these reasons, we study the basic principles and parameters of the traditional PIDcontroller tuning method, the conventional fuzzy controller structure and design steps. Thenaccording to the characteristics of the hydraulic AGC hydraulic servo system, fuzzy control and PID control, the advantages and disadvantages of the traditional PID control and fuzzy controltechnology combined with design a fuzzy adaptive PID controller. On the basis of theconventional PID control, the controller, according to the thickness error and the rate of change,combined with changes in charged with the dynamic characteristics of the process by fuzzyrule-based reasoning, the PID parameters online self-tuning, thereby increasing the thicknesscontrol accuracy. And through MATLAB simulation experiments, the effect of the conventionalPID controller and fuzzy adaptive PID controller of the control compared to simulation resultsshow that the fuzzy adaptive PID control and conventional PID control, has a good dynamicand steady-state performance and strong robustness, and better control.In addition, this paper attempts to thickness control system and SCM control technologycombination of using MCU to complete the self-tuning fuzzy reasoning algorithm and PIDparameters, the whole control system through the MCU all-digital processing. This paperintroduces a single-chip fuzzy adaptive PID control system structure，thought control, controlalgorithms, and gives the system hardware and software design. This method can simplify thestructure, enhance operational flexibility, reliability and adaptability, it is simple, versatile,engineering, and convenient debugging.