Modeling and Stability Analysis of a Double-Fed Wind Power System Based on the VSG Synchronization Mechanism

To address the issues of insufficient inertial support and reduced stability in doubly-fed wind power systems under high-penetration renewable energy grid integration, this paper conducts modeling and small-signal stability analysis of a doubly-fed wind power grid-connected system based on the VSG synchronization mechanism. A complete mathematical model is established, encompassing the wind turbine, drive train, DFIG, converter, VSG control, inner-loop control, and filter network, and a small-signal state-space model of the system is constructed. Using eigenvalue and root locus methods, the study analyzes the effects of key parameters—such as virtual rotating inertia, active power droop coefficient, and filter inductance—on the system’s damping characteristics and oscillation modes. The results indicate that the developed small-signal model accurately characterizes the system’s dynamic behavior and exhibits high consistency with MATLAB/Simulink simulation results; an increase in virtual rotating inertia weakens system damping and reduces dynamic stability; a reasonable increase in the active droop coefficient helps improve damping characteristics; excessive filtering inductance causes the characteristic roots to shift toward the imaginary axis, thereby reducing the system’s stability margin. This study provides a theoretical reference for parameter optimization and stable operation of doubly-fed wind power systems based on the VSG synchronization mechanism.