Abstract:

For the problem of coupling in a class of multiple input multiple output（MIMO）systems，this paper proposes a dynamic nonlinear decoupling control method based on active disturbance rejection control（ADRC）.This method does not rely on the accurate model of the system.According to the partly known and unknown coupling matrix of the controller respectively，this method takes the model perturbation，the external disturbance and the dynamic coupling including the interaction of the input variables as a total disturbance to each channel based on the local static decoupling.By introducing virtual control and state variables，the extended state observer（ESO）is designed to estimate the total disturbance and then it is fed back to the controller to compensate the disturbances.And then，the non-linear SISO ADRC is designed to ensure the stability of the closed-loop system for each decoupling sub-object.Finally，the simulation results of a distillation column model control show that the designed controller not only has good decoupling performance，but also ensures good robustness and adaptability in the condition of modeling uncertainty and external disturbance.