Integration of power decoupling buffer and grid-tied photovoltaic inverter with single-inductor dual-buck topology and single-loop direct input current ripple control method

Abstract

Dual-buck inverters feature some attractive merits, such as no reverse recovery issues of the body diodes, free of shoot-through, high efficiency and low leakage current. However, volume and weight of the system, power density must be reconsidered in the dual-buck based single-phase grid-tied photovoltaic (PV) inverter, because its twice inductor capacity and bulky electrolytic capacitor for the inherent double-frequency ripple power decoupling. Thus, a new integration of active power decoupling buffer and grid-tied photovoltaic inverter with single-inductor dual buck topology is proposed in this letter. The working principle is explained, and a new single-loop direct input current ripple control method for active power ripple decoupling buffer is proposed. Finally, the effectiveness is verified by experimental results.