Estimation and Influencing Factors Analysis for Equivalent Inertia of Wind Turbines with Active Inertia Support

The reduction of disturbance rejection ability of low inertia power systems caused by the integration of wind power is becoming more and more prominent, and the safety and stability of the system frequency are facing great challenges. At present, wind turbines (WTs) mainly apply several inertia support methods to reduce the unbalanced power of the system under load disturbance and this can effectively suppress the change of the system frequency. However, except for virtual inertial control, it is difficult for the WTs’ inertia support methods to make the system frequency dynamic consistent with the inertia response characteristics of traditional synchronous machines. To quantify the equivalent inertia provided by WTs with different inertia support methods for the grid, this paper proposed an equivalent inertia estimation method for WTs based on the perspective of frequency dynamic response equivalence, conducted simulation analysis on its influence factors, and compared the equivalent inertia of WTs applying different inertia support methods.