Voltage Fluctuation Control of APF DC Side Based on Active Power Decoupling

In order to solve the problem of DC side voltage fluctuation when APF compensates nonlinear load, this paper proposes a DC side voltage fluctuation control strategy. In this method, a bidirectional buck-Boost active power decoupling circuit is extended in the DC side of the APF to transfer the DC side fluctuation power of the APF to the active power decoupling circuit, so as to control the DC side voltage fluctuation. The electrolytic capacitor with a large capacitance is replaced by a film capacitor with a small capacitance. Finally, the simulation results show that the proposed control strategy can improve the compensation capability of APF and has a certain prospect of engineering application.