SOLAR PHOTOVOLTAIC GRID-CONNECTED INTERLEAVED PARALLEL FLYBACK INVERTER

摘要

Provided is a solar photovoltaic grid-connected interleaved parallel flyback inverter, comprising an interleaved parallel flyback circuit; a DC detection module; an AC detection module; a reference current acquisition module for obtaining the reference current at each time point; a quasi-resonance control circuit for sampling the drain source voltage of a switching tube and comparing whether the drain source voltage equals to a quasi-resonance threshold value; a primary-side current sampling module; and a driving circuit for generating a driving signal. The driving circuit comprises: a comparator for comparing whether the primary-side current equals to the reference current; and a trigger for driving the switching tube to switch off when the primary-side current equals to the reference current, and driving the switching tube to switch on when the drain source voltage equals to the quasi-resonance threshold value. Also provided is another solar photovoltaic grid-connected interleaved parallel flyback inverter. The present invention uses the reference current to control the inverter to convert energy, improves the calculation method of the reference current in a two-stage circuit topology, and ensures that the grid-connected current has a sinusoidal waveform with the same frequency and phase as an electric grid, thus reducing the THD of the grid-connected current and improving the quality of output electric power.