Designation of a flexible PV grid-connected inverter based on SVPWM

This paper put forward a novel grid connection method of three-phased PV inverter by analyzing the principle and vector composition of voltage space vector based on the model of asynchronous machine, in which the synthetically control scheme of grid voltage controller and current PI controller addicted with flexible unit under two phase synchronous rotating frame is proposed, a compacted hardware and software phase locking method is developed. The flexible unit can make amplitudes of currents increasing softly to achieve soft starting. Finally, experimental results obtained from a 6kVA inverter prototype are presented to verify the viability and effectiveness of the proposed method.