Active disturbance rejection control based simplified decoupling for two-input-two-output processes

In this paper, Maclaurin expansion and Padé approximation are utilized to handle the RHP zeros in the simplified decoupling control and the choosing strategy is given. To improve the robustness of each loop, Active Disturbance Rejection Control (ADRC) is adopted as a good solution which can estimate and compensate the total disturbances by the extended state observer (ESO). Besides, the stability region of the closed loop with ADRC is calculated to benefit for the parameters tuning and μ-analysis is used to analyze the robustness with different controllers. The simulation results demonstrate the advantage of ADRC based simplified decoupling in tracking performance and robustness.