Research on Current Control of Photovoltaic Grid-connected Inverter

In photovoltaic grid-connected system,the method of adding voltage feed-forward to improve the shape of grid-conected current wave is presented,the reason for the introduction of the net voltage feed-forward decreasing the phasic difference between grid-connected current and net voltage and reducing the THD of grid-connected current is analyzed.It is confirmed that the net voltage feed-forward compensation can improve grid-connected current availably by the results of simulations and experiments,keep the current frequency and phase synchronous to the grid.