The paper studied a kind of micro-grid inverter overall control strategy based on virtual synchronous generator algorithm. According to the body mathematical model of synchronous generator, a modulation of primary frequency and reactive voltage regulating characteristic, designed a virtual synchronous generator algorithm, prime mover adjustment and excitation current adjustment model respectively, at the same time through with better tracking effect of the voltage current double loop control strategy, making the inverter output voltage amplitude and frequency with good droop, the adjustable rotational inertia and better tracking performance and improved the stability and reliability of the system. In addition, in the grid system frequency under the condition of high control precision and real-time response, the paper improved the virtual prime mover control module, and frequency has been achieved without error control, which improved the control precision and response speed of frequency. Finally built model and simulated in the matlab/simulink, inverter output voltage simulate the external characteristics of synchronous generator betterly , single-phase voltage distortion rate of 0.2 percent , and after the introduction of improved prime mover adjustment module , the output frequency does not change with the load shifted, eventually stabilize at 49.98Hz, which verified the correctness and feasibility of the theoretical analysis.