State space predictive functional control optimization based new PID design for multivariable processes

• A PFC optimization scheme based MIMO PID is proposed.
• The control is applied to chamber pressure control in a coke furnace.
• Improved control performance is obtained under model/plant mismatch.

Proportional-integral-derivative (PID) controller encounters challenge when dealing with the multiple input and multiple output (MIMO) industrial processes, because the coupling, time delay and other characteristics make the design of PID controllers complicated. A novel PID controller based on extended non-minimal state space predictive functional control (ENMSSPFC) is proposed to control the chamber pressure of an industrial furnace where the process is a typical MIMO process. ENMSSPFC is an improved predictive functional control (PFC) algorithm in which the state variables and the tracking error are combined and regulated separately, so that more freedom can be offered in the adjustment and better performance can be provided. The new PID controller inherits the simple structure and the improved performance of ENMSSPFC, and two case studies of pressure regulation in the industrial chamber and Vinante and Luyben (VL) column system are introduced to show the effectiveness of proposed method.