High-frequency DC link flyback single phase inverter for grid-connected photovoltaic system

This paper discusses a novel single-phase flyback inverter, which is composed of a Boost converter and a flyback inverter suitable for ac PV module systems. Multilevel pulse train technique and DCM operation is used for Boost converter to generate a stable dc voltage. The output voltage ripple of the converter can be reduced effectively and the dynamic response can be faster. And a reduction in the total capacitance on the Dc-Link is realized. For the flyback inverter, a peak-current mode control scheme is employed to draw a sinusoidal output current into the AC grid. The simulation results show that the proposed inverter has the properties of high power factor, low cost, low current distortion and small volume.