Grid-Voltage-Sensorless Method Based Continuous Sliding Mode Control of Three-Phase Active Power Filter

In this paper, a grid-voltage-sensorless method based continuous terminal sliding mode control (GVSCTSMC) is proposed for active power filter. First, the dynamic model of three-phase shunt active power filter is introduced. Second, a voltage observer is developed to replace the grid -voltage sensor to eliminate the influence of sensor fault using the second order generalized integral principle (SOGI). Then a continuous terminal sliding mode control is designed to guarantee the fast and finite -time tracking of reference current. In addition, compensation control term is added 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.