Abstract: Aiming at the difficult problem of dynamic performance index and parameter optimization in a doubly fed induction generator（DFIG）controlled by a virtual synchronous generator（VSG）based wind turbines,which is difficult to solve due to the high order of the model,taking into account stability and dynamic performance,an improved model reduction method of the approximate combination of Routh Hurwitz and Pade approximations method is proposed. Firstly,the mathematical model of DFIG-VSG is established,and a double-loop control strategy for the decoupling of rotor current feedforward compensation is proposed. Then the small signal model of the DFIG-VSG grid-connected system is established,and the corresponding high-order closed-loop transfer function is obtained. Based on the model reduction method proposed in this paper,the second-order transfer function of the output active power can be obtained by reducing the DFIG-VSG high-order transfer function,and a set of control parameter selection ranges can be obtained by constraining the dynamic parameters and stability margin,and the influence of the main control parameters on the DFIG-VSG grid-connected system is analyzed by the root trajectory method in this selection range. Under different wind speed conditions,Matlab/Simulink simulation verifies the feasibility of the proposed method.