Active Disturbance Rejection Controller for high-order system

High-order system is difficult to be controlled effectively for its special characteristics. In this paper, the second-order linear Active Disturbance Rejection Controller (ADRC) is applied to the control of the high-order systems which are constructed by a series of inertia elements. The simulation results show that the second-order linear ADRC can estimate precisely and compensate both the inner and outer disturbance instantly, and does not depend on the accurate model of the plant, and plays good performance and robustness in the control of high-order system.