Research Of Laminar Cooling Control System For A Hot Strip Mill Based On Model Free Adaptive Control

Coiling temperature is one of the key factors which influence the microstructure and properties of hot strip mill.Whether the actual coiling temperature can be controlled in the required range mainly depends on the laminar cooling control.When the actual coiling temperature exceeds the required range,the microstructure and properties of the steel roll will become worse.So it is an important problem for the hot strip mill to increase the temperature control accuracy of the coiling temperature.Based on the laminar cooling control system of a 1580mm hot strip mill factory,some deep thorough research to the laminar cooling control system is conducted in this thesis.This thesis analyzes the development of the domestic and international cooling control technologies and equipments.According to the characteristics of the process and equipment of a 1580mm hot strip mill line,the equipment and the process of laminar cooling are analyzed in detail.According to the requirement of control,the method of laminar cooling control is studied.The main work is as follows:(1)According to the characteristics of laminar cooling process and equipments,the calculation model of rolling workpiece temperature,feed forward and feedback control model are established,and the data preparation and processing,pre setting calculation,fixed setting calculation,feedback control and self learning model are designed.(2)Referring to the pure lag in feedback control and the imprecision of the controlled object model,the method of model free adaptive control(MFAC)is studied and improved in this thesis.Through theoretical analysis,the model free adaptive control has the following features:1)MFAC,which only depends on the real-time measurement data of the controlled system and does not rely on any mathematical model of the controlled system,is a control method of data drive;2)MFAC does not require any external test signal or training process,so MFAC is a low cost controller;3)MFAC has the characteristics of simpleness,light computation burden,easy to implement and strong robustness.(3)Based on the improved MFAC,a temperature control system is designed.The simulation of the system is carried out with the Simulink simulation tool in MATLAB.The simulation analysis shows the method of improved MFAC for laminar cooling control is effective.