Abstract: After the integration of new energy sources with typical characteristics of "small inertia and weak damping" into power grid, the active power of AC bus will experience severe fluctuations when the power system is disturbed, leading a potential threat to the frequency stability of power grid. Therefore, an improved parameter adaptive control strategy based on virtual synchronous generator（VSG） is proposed in this paper. Firstly, controlling the inverter to operate in VSG mode and making the virtual inertia and damping parameters associate with the deviation and rate of change of VSG output angular frequency during operation, in order to achieve the aim of smoothing frequency fluctuations. Then, in order to avoid unnecessary noise interference caused by the derivative operation in adaptive control upon the system, further adaptive optimization control is carried out on the inverter, replacing angular frequency derivative term in the original control link with power deviation, as simplify the control link, and improve the dynamic regulation waveform of grid frequency. Finally, the correctness of the proposed adaptive control strategy was proved through simulation examples, and the effectiveness of the presented strategy in suppressing active power and frequency fluctuations under disturbances was verified.