A new active power decoupling using Bi-directional Resonant Converter for flyback-type AC-module system

In general, the photovoltaic (PV) power generation system has mismatch problem between oscillated AC power and constant input DC power. It has been solved by using large electrolytic capacitors. However, due to the low life span of electrolytic capacitors, the active power decoupling method is studied to substitute from the conventional type capacitor to film capacitor. This paper proposes new active power decoupling using bi-directional Resonant Converter (APD-BRC) for flyback-type AC-module system. Proposed APD-BRC circuit is composed of bi-directional buck-boost converter using soft-switching and it expected higher system efficiency than conventional decoupling system. Since voltage ripple of PV module output is reduced, electrolytic capacitor can be replaced to film capacitor. The proposed topology is verified by simulation results.