In this digest, a novel single-stage single-phase microinverter with a beat frequency modulation (BFM) and fully soft-switching operation is presented for photovoltaic (PV) applications. The proposed microinverter is configured based on a resonant LLC converter to provide both amplification and isolation. A new frequency modulation is applied to the converter to provide a pure sinusoidal waveform at the output of the microinverter. The soft-switching conditions are provided for all switches of the converter due to the utilization of the resonant elements. The rectifier and unfolder at the output stage of the microinverter are merged together to utilize the minimum number of semiconductors. A new control strategy is employed to provide the output current regulation.
