Analytical design based hierarchical control for non-square MIMO wood-chip refining process.

This paper presents an analytical design based hierarchical control method for non-square MIMO wood-chip refining process, whose design procedure of the control scheme contains two layers. Firstly, the lower layer loop controller with PID structure is designed separately for the mutually independent lower layer device plant, and then generalized non-square process is obtained on the basis of lower layer closed-loop system and non-square MIMO refining process. Secondly, the upper layer setting controller with the centralized PID structure is designed by the multivariable decoupling control and internal model control (IMC), and an analytical designed method for the lower layer loop controller and the upper layer setting controller is developed using the maximum sensitivity (Ms ) specification. Finally, Simulation results demonstrate the effectiveness of the proposed method for control and optimal operation of the non-square MIMO refining process.