Research on the Current Controller of Three Phase Photovoltaic Grid-connected Inverter

The harmonic component of output current of grid-connected inverter,which will feed into grid,is limited by some criterions.This paper analyzes some factors that will affect the quality of inverter's output current and develops mathematics model of output current.A novel current control scheme,which is the combination of PI controller and repeti-tive controller,is presented.Finally,a laboratory prototype has been designed to verify the discussion and analysis.The ex-perimental results show that the proposed scheme can work well.Highly accurate steady output and less harmonic distur-bance is gained.