Fuzzy logic based switching state selection for virtual flux DPC of shunt active filter

Active filters are effective for eliminating harmonic currents and compensating reactive power in the presence of non-linear loads and unbalanced sources. In this paper, a new strategy for control of shunt active filter is proposed. Fuzzy logic based switching state selection Direct Power Control (DPC) is employed for this control scheme. In addition, the AC line voltage sensors with a virtual flux (VF) estimator are replaced. To retrieve the phase and the frequency information, we have integrated a phase locked loop (PLL) control method. The advantages of this strategy are the simple algorithm, good dynamic response and resistance to the majority of the line voltage disturbances. Indeed, the operation of a proposed control strategy is implemented and verified in Matlab/Simulink´s simulation environment. The results show that the control algorithm of the active filter is effective for eliminating harmonic currents and improving reactive power injected from nonlinear loads, which allowed us to confirm the robustness of the proposed strategy.