Resonant Flyback PV Microinverter With Low Component Count

This paper presents a resonant flyback photovoltaic microinverter with reduced number of power components. Unlike conventional flyback converter, it transfers energy in a resonant manner during the first half of the switching period and in a linear way during the remaining half of the switching period. It operates in dual-mode: below resonance mode (BRM) above the computed instantaneous power level and above resonance mode (ARM) below this instantaneous power level. Secondary diodes of the resonant flyback converter are integrated into two of the secondary-side switches in the proposed inverter configuration, which reduces the number of active-power components. The operation principle of the inverter is presented and analyzed. Experimental results for a prototype 200-W inverter verify these characteristics.