The whole circuit model of grid-connected PV system was built based on two-stage structure that boost convertors link Single-phase full bridge inverter. The three-terminal switching modeling method was adopted to set up Period Average Model of Boost convertors, which used the switching function model and Fourier series to study the DC-side input resistance of inverter by multiple-frequency pulse width modulation mode. The qualitative relation to the circuit parameter and calculation formula of impedance was deduced and the influence of different modulator mode. to impedance was analyzed. The v...
