Phase-locked loop（ PLL） and virtual synchronous generator are two methods for grid-connected inverter to keep synchronization with power grid. For traditional phase-locked loop frequency tracking performance is poor in synchronous generator system

the problem of low dc interference resistance

application based on the secondorder generalized integrator（ SOGI） phase-locked loop structure

three-phase VSG system model is established

combined SOGI-PLL and VSG technology

set up based on SOGI-three-phase VSG PLL system model and simulation

the simulation results show that SOGI-PLL can get accurate phase information of power grid by phase lock

improve grid current voltage quality

reduce the harmonic pollution

can effectively improve the stability of three-phase VSG system. Finally

the accuracy of the proposed structure is verified by ModelingTech power electronics simulation experiment system.