Cold Continuous Rolling Mill Control Strategy Research Based On Virtual Rolling System

Automatic gauge control system is one of the important links of mill’s system designand development, the design and simulation debugging of mill’s AGC system is necessaryto be solved for the design of new mill and reconstruction of existing rolling mill.Development of virtual mill provides great convenience for the control system design anddebugging. At any time in the process of rolling mill simulation one or several AGCcontrol strategies could be involved, and the simulation of complex continuous motioncould be realized.In this paper, an approach for virtual rolling was proposed, With C language andMatlab, cold rolling mill virtual control system was built on the platform ofMATLAB/SIMULINK software for the five cold rolling stand.Firstly, a complete virtual AGC control system is established. With the use of C MEXS-Function, the control strategies for each rack was simulated, including feedforwardAGC, load roll gap control and monitor AGC of stand1, feedforward AGC of stand2,feedforward AGC and monitor AGC of stand4, feedforward AGC and monitor AGC ofstand5. The function of control strategies alone or free combination was programmed.Secondly, Connecting the virtual control system and existing virtual rolling mill, acomplete simulation mill AGC system was established. Simplifying the incoming stripthickness fluctuations with a simple step signal, the different control strategies wassimulated separately or freely combined. Through analysis of impacts of different controlstrategies on strip thickness, the tension between the racks, rolling pressure and speed, anddeviation of export finished strip, correctness of C language code program of the virtualcontrol system has been proved. This C language code could be used in the research ofhardware in loop real time simulation for tandem cold rolling.Finally, with the actual strip data, the entire automatic gauge control system wassimulated and tested. Analyzing control effect and comparing the results with the actualrolling data, ultimately the effectiveness of virtual control system was verified.