Abstract: The conventional control strategy of the virtual synchronous generator with the fixed parameters has a great effect on the transient process of the system because it is not able to give a full play to the advantages of the flexible and adjustable inverter parameters. Therefore, an adaptive cooperative adjustment strategy of the P/ω droop coefficient, the virtual inertia and the damping coefficient is proposed. Through the mathematical modeling for the dual-machine parallel virtual synchronous generator (VSG) grid-connected system, the VSG transient process is segmented and analyzed to obtain the regulation laws of the parameters in different stages. Combined with the system inertia damping and the P/ω droop coefficient, the small signal model is analyzed to determine the ranges of the P/ω droop coefficient and the damping coefficient. The variations of the VSG angular velocity and the instantaneous change rate of the angular velocity are associated with the inertia damping to realize the adaptive cooperative adjustment of the inertia damping, and the adaptive adjustment of the P/ω droop coefficient is carried out in real time according to the variation of the VSG angular velocity. Finally, a dual-machine parallel VSG grid-connected system is built in the MATLAB/Simulink simulation platform. In the cases of the load fluctuation, the output fluctuation and the AC side short circuit fault, the transient frequency fluctuations of the grid-connected VSG system under different parameter selection strategies are compared to verify the effectiveness and superiority of the proposed parameter adaptive selection strategy.