Active disturbance rejection control for discrete systems with zero dynamics

In this paper, a discrete active disturbance rejection control (DADRC) scheme is proposed to manipulate linear input–output systems with zero dynamics. The DADRC is formulated according to the relative degree of the system output and is designed to track a reference and cancel both internal uncertainties and external disturbances. A parameter tuning method is also presented based on a part of the model information. The robustness and effectiveness of the designed scheme are demonstrated via numerical simulations.