Application of Dual Switch Flyback Converter in Three-Phase Photovoltaic Inverter

Abstract

Auxiliary power of Three-phase photovoltaic inverter is supplied by solar cells with wide input ranging from 140V to 1000V.The conventional single-switch flyback converter exists too high voltage stress in power switch to be applied in this inverter. This paper presents a dual-switch flyback converter in which the voltage stress of each switch is slightly higher than the input voltage when switches turn off, at the same time , the leakage inductance energy is recycled back into the inputside; otherwise, this topology needs no snubber circuit, so it is much more efficient than single switch flyback. The dual switch flyback converter with seven outputs is successfully applied in 10KW three phase PV inverter.