Design and implementation of boost-type flyback PV inverter

This paper presents a PV inverter system formed by a DC-DC converter and a full-bridge DC-AC converter. The DC-DC converter combines the boost and flyback topologies to produce a semi-sinusoidal output current and to achieve the high step-up objective. A full-bridge DC-AC converter controlled with low-frequency switching techniques is then used to convert the current into sinusoidal form and to feed power to the grid with unit power factor. The overall efficiency of the designed system is high due to the losses of both stages are reduced. The circuit operating theory of the proposed PV inverter is firstly addressed then an 80 W prototype system is designed and built. The feasibility and effectiveness of the proposed circuit are confirmed with some simulation and experimental results.