Active Disturbance Rejection Control of Active Power Filter

This paper presents an Active Disturbance Rejection Control (ADRC) technology and PI-fuzzy compound technology method for Active Power Filter (APF). The ADRC consists of Tracking Differentiator (TD), Extended State Observer (ESO) and Nonlinear State Error Feedback law (NLSEF). This control method makes full use of the error driven control law, the modern control theory and the nonlinear feedback control. The APF control system is designed with two closed loop; reference current tracking loop with ADRC and the voltage controlling loop with the PI-fuzzy compound controller. Comparing with the direct current control technique, simulation results verify that the proposed control method has excellent dynamic performance and strong robustness in the presence of model uncertainty as well as external disturbances.