Self-adaptive Equivalent Modeling for Small Signal Stability Analysis of Wind Farm under Wind Speed Variation

With the development of renewable energy generation, the increase of wind turbines makes stability analysis difficult. Aiming at this problem, this paper proposes a self- adaptive equivalent modeling of wind farm with various wind speed for small signal analysis. Firstly, the frequency domain model of wind farm is constructed, and the small signal impedance model of wind turbines is changed to the external circuit by Schur transform. Then, we decompose the dynamic characteristics of the wind turbines, compare the system’s eigenvalues under the dominant mode and categorize the turbines. The number of equivalent turbines is determined by turbine control parameters and network topology. Finally, the equivalent parameters are calculated to build the equivalent model. The simulation result, based on the MATLAB/Simulink platform, verifies the rationality of the proposed self-adaptive equivalent modeling method.