Disturbance observer enhanced PID decoupling control for multi-variable processes

Multi-variable processes with coupling are common in process control industries, yet many control schemes in previous literatures demonstrate the limited abilities in the presence of strong disturbances. A disturbance observer (DOB) enhanced PID control strategy, including a feed-forward compensation part based on DOB and a feedback regulation part based on PID, is proposed to improve the disturbance rejection ability for multi-variable process systems in this paper. Simulation results illustrate that the proposed method significantly improves the disturbance rejection property for multi-variable processes.