Modeling Method for Power Response Characteristics of DFIG-based Wind Turbine System

In order to analyze the grid-connected characteristics of doubly-fed induction generator (DFIG) based wind turbines, it is extremely important to establish an accurate model of the power response characteristics at the grid-connected point. A modeling method is proposed to solve the modeling problem of the power characteristics of DFIG-based wind turbines at the grid-connected point. First, aiming at the vector control and virtual synchronous generator control in the DFIG-based wind turbine system, power response characteristic models are established and analyzed separately. Then, based on the power response data at the grid-connected point obtained by applying the power disturbance command to the DFIG-based wind turbine, the optimal adjustment method of the damping factor in the damping least square method is proposed, and the model is identified based on the improved method to realize the fitting of the power response characteristics at the grid-connected point. Moreover, the influence of generator parameters of DFIG-based wind turbines on model fitting error is analyzed, whose influence degree through parameter trajectory sensitivity calculation is analyzed, and combined with simulation, the applicable scope of the model is further clarified. Finally, simulation and experimental results verify the rationality of the built power response characteristic model and the effectiveness of the proposed modeling method. © 2022 Automation of Electric Power Systems Press.