Continuous Terminal Sliding Mode Control for Active Power Filter

In this paper, a continuous terminal sliding mode control methods (CTSMC) are proposed for three-phase shunt active power filter as current controller. First, the dynamic model of active power filter with parameter perturbation and unknown external disturbance is introduced. Second, a continuous terminal sliding mode control applied to current control loop is designed to guarantee the fast and finite-time convergence. Moreover, compensation control term is designed to ensure the elimination of chattering phenomenon caused by the switching term. Compared to the conventional sliding mode control method, the proposed continuous terminal sliding control method obtains a faster convergence and better tracking performance. Simulation results demonstrate that the proposed control methods offer superior properties in both steady state and transient operation, reducing the THD of source current to less than 5% and improving the power quality in order to meet the recommendations of the IEEE 519 standard.