High-Efficiency Isolated Photovoltaic Microinverter Using Wide-Band Gap Switches for Standalone and Grid-Tied Applications

Abstract

An isolated photovoltaic micro-inverter for standalone and grid-tied applications is designed and implemented to achieve high efficiency. System configuration and design considerations, including the proposed active-clamp forward-flyback resonant converter for the DC-DC stage and a dual-frequency full-bridge inverter for the DC-AC stage, are analyzed and discussed. A prototype microinverter system is built and tested. Experimental results verify the feasibility of the proposed system, which achieves 95% power conversion efficiency at full load.

Keywords

• photovoltaic
• microinverter
• grid-tied inverter
• wide-band gap switches
• high switching frequency
• high power density
• photovoltaic applications
• power electronics
• solar energy