Aluminum Strip Cold Rolling Mill Plate-shaped Plate Thickness Decoupling Control Strategy

As we know, strip flatness and gauge geometry dimension accuracy are the most important factors of product quality. The Automatic Gauge Control (AGC) system can guarantee the precision of the vertical thickness of aluminous board and strip and the Automatic Flatness Control (AFC) system can guarantee the precision of the horizontal thickness of aluminous board and strip. With the development of past few decades, both AFC and AGC can be obtained rather degree of control accuracy. However the Flatness and Gauge Control (AFC-AGC) system is a coupled complex multivariable control system, Gauge control and Flatness control are both master of the aperture of cold mill during the process of aluminous timber rolling, and intense coupling connection exists in both of their control loops, it is an active demand to solve the problem to improve control precision ulteriorly.The cross coupling process between AFC and AGC is real-time and dynamic, on the basis of deformation mechanism of AFC-AGC system, a dynamic coupling model and the corresponding dynamic decoupling control strategy are built, the decoupling methods applied to the production mill have been proved to be effective with the simulation experiments result. The main study content is described as follows:The strip rolling process is analyzed by the method that considers the AFC and AGC as a whole process in the research, and the dynamic mathematics model is proposed. The decoupling control based on the invariability principle and the PID control arithmetic is implemented when getting the dynamic mathematics model of the AFC-AGC system, and the dead-time tache is disposed with Smith-predictor at the same time, the decoupling control effect is proved by the simulation result, and the coupling influence of flatness and gauge control is decreased. The decoupling control performance will break up while the model parameters of the system change in the process of running. According to self-adaptive control of model reference and decoupling theory, the multivariable self-adaptive decoupling control method which solves the uncertain factor of system model parameters that affect the problem of control performance in the decoupling process is put forward, and the simulation result indicates the control precision is improved with this control strategy. As the setting control is the start point of dynamic control of AFC-AGC system, and the effect of dynamic control of the system will be influenced by it, therefore the static coupling model based on setup control is constructed, and the compensatory decoupling method in flatness and gauge setup programs is put forward, which makes decoupling control strategy of AFC-AGC system more integrity.The obtained harvest is general for the production process of board and strip, and it provides a good reference for the application of decoupling control theory of AFC-AGC system.