Active disturbance rejection decoupling control for strip width and gauge multi-systems

A new control solution to finishing automatic width control (FAWC) and automatic gauge control (AGC) is proposed based on active disturbance rejection controller (ADRC) because the plant is of serious decoupling, large time-delay, uncertainty, many disturbances and nonlinear etc. A new kind of static and dynamic decoupling way based on extended state observer (ESO) is presented to eliminate the coupling between FAWC and AGC. In order to produce the fast transient response of the time-delay system, the proposed ADRC consists of the ESO and nonlinear state error feedback (NLSEF) without tracking differentiator (TD). The performance of NLSEF is improved by using a nonlinear function and the order of ADRC is lower than the routine ADRC. Simulation results show that the designed controller not only has good decoupling performance, but also ensures good robustness and adaptability under modeling uncertainty and external disturbance.