Realization study of interleaved PV microinverter by quadrature-phase-shift SPWM control

Abstract

A PV microinverter implemented using interleaved flyback converter (IFC) is investigated. Double-frequency distortion is found in grid current because of using sawtooth time-based SPWM. A forward compensation circuit that eliminates the distortion at primary side is explored that simplifies the output filter design. Maximum power transfer between PV module, IFC, and grid end is modeled. An elaborate experiment is demonstrated to verify the analysis result and performance predictions.