Research on the Fluctuation of Panels Input Current of Single-phase Photovoltaic Grid-connected Inverter

The power circuit of the single-phase PV inverter uses two-class form,the former class is to rise voltage,the post-class adopts full-bridge inverter to fulfill the change of DC/AC.Because the output power is AC,and the in-put power is a fixed-value,this topology will lead to the fluctuation of the input current.The power transfer process is analyzed meticulously,a theoretical derivation to voltage fluctuations of the generatrix capacitor and the impact of such fluctuations on the input current is given,and according to its characteristics,the corresponding correction con-trol algorithm of subdivision control is raised.The feasibility of the solution is verified through the 3 kW experimental prototype,and the corresponding waveform is given.