Abstract: As the new photovoltaic energy access to the power grid through the power electronic interface, the power system, which was originally dominated by the synchronous generator, is transformed into a high frequency power electronic power system. In view of the problem that large scale photovoltaic power grid connected to the power grid leads to the smaller inertia moment of power system, the control strategy of the virtual synchronous generator is adopted in the bipolar three-phase grid system. The simulation results in Matlab/Simulink show that the PV grid system with the control strategy of virtual synchronizer can simulate the inertia and frequency modulation characteristics of the traditional synchronizer.