Reversible Cold Rolling Mill Of The Adaptive Smith Predictor-based Feedback Agc Control Strategy

The thickness accuracy and shape accuracy are the two important quality indexes of aluminum plate strip, and automatic gauge control is the key technology to improve the quality of aluminum plate strip. Huge advancements have been derived with the development of rolling technology, control theory and artificial intelligence theory and with their applications in rolling process. As a multi-varible and strong coupling complex process, there exists theory significancy and application value to use cooperative gauge control strategy in single stand reversible cold rolling mill for the purpose of realizing aluminum plate strip high level gauge control accuracy.Base on the platform of Southwest Aluminum Corporation 1,850mm reversible cold rolling mill control system, the correlative theories and applications of automatic gauge control system are researched, which provides theory base to the research of cooperative gauge control strategy used in single stand reversible cold rolling mill.Different conventional automatic gauge control methods of aluminum plate strip rolling are described in detail; factors that affect the exit-thickness deviation are analyzed thoroughly, and the application characteristic of different AGC control methods used in rolling process are researched deeply, finally, according to the working performance of aluminum plate strip in rolling, the cooperative automatic gauge control strategy for single stand reversible cold rolling mill is obtained. Considering the characteristic of time-delay exists in feed-back AGC which cause a scarcity of response delay when hydraulic pressure system of rolling mill adjusting its gap, combining with the compensation function of Smith predictor used in time-delay process, this paper uses a structure modifyed Smith predictor to eliminate the response delay performance of feed-back AGC, and introduce model reference adaptive technology so that the object model parameters and predictor parameters can maintain congruously to overcome the influence on model parameters matching accuracy when parameters change in rolling process.The simulation result shows that the gauge control strategy base on model reference adaptive Smith predictor can boost the gauge accuracy of aluminum plate strip; it has an important application value in practicality.