Research on application of Smith predictor to monitor AGC in hot strip rolling mills

Abstract

Because of the long distance between the last finishing mill and the X-ray Thickness Gauge, there was a long delay time for the AGC system to get the gauge error information feedback, which has some negative effect on the control of strip thickness, so the monitor AGC was not a control system in time. According to the virtual model fitted by true measured parameters, the Smith predictor in the monitor AGC was applied to predict the gauge error in the finishing mill and used this gauge error to control the strip rolling mill. As a result, not only the mill response to strip gauge error was mended and the control system stability was improved, but also the strip gauge precision was obviously improved when the Smith predictor was implied to the industrial site.