Synchronization Control to the Hydraulic Width System in Hot Rolling

Edger rolling mill is a load system in which the upper and the lower cylinder actuate a side edger roller at the same time. Due to the linkage of the load, the output and control of two systems influence each other. And when the two systems´ component and load are different the un-synchronous motion will occur. To the synchronizing problem of two cylinders an adaptive robust control algorithm is proposed to improve synchronization performance. Firstly, the system is divided into two parts, one is linear two-input two-output system, and the other is the single input single output nonlinear system with parameter time varying. Afterwards, a two-step nonlinear motion synchronization controller is proposed to address the synchronization issue. The two-step controller utilizes linear MIMO robust control technique to design an outer-loop synchronization controller. A nonlinear SISO controller with Lyapunov-based parameter adaptive is then designed for each cylinder as the inner-loop controller. A series of simulation works shows the two-step controller is valid.