Abstract: In response to the current situation of high proportion of renewable energy access and high proportion of power electronic equipment application, the lack of damping and inertia in the operation of photovoltaic microgrids can easily lead to large fluctuations in bus voltage and system frequency. This paper proposes a virtual synchronous generator (VSG) control method that simulates the external characteristics of traditional synchronous generator operation. Virtual inertia and damping are introduced into the inverter control link to improve system robustness. Firstly, compare and analyze Droop Control and VSG Control, mathematically derive the working principle of VSG, and provide a detailed introduction to the modeling process; Secondly, establish a small signal model under off grid conditions and draw the system root trajectory to conduct stability analysis on the selection of VSG parameters; Subsequently, the influence of key parameters such as rotational relationship and damping coefficient on the power and frequency characteristics of the system was studied; Finally, the dynamic response processes of droop control and VSG control were simulated and compared in MATLAB/Simulink. The results indicate that under VSG control, the bus voltage and system frequency have smaller fluctuations and stronger elasticity, effectively improving operational stability.