Wind Farm Dynamic Equivalencing with Wind Turbine Rotor Dynamics

The main theme of this paper is focused on the dynamic analysis of large-scale wind farm connected with the power system. Detailed modeling of large-scale wind farms, which may contain a large number of wind generators, will result in inconvenience to the task of system analysis due to the computational complexity. The use of dynamic equivalencing method to obtain the dynamic model of wind generators in the wind farm will reduce the model order of the overall power system and is helpful to the task of dynamic analysis. In the beginning, we establish dynamic models for all wind turbines in the wind farm. Coherent groups of the doubly-fed induction generators with same or similar characteristics are identified. Then we utilize the method of time-domain identification to aggregate those generators in a coherent group to obtain the parameters of the dynamic equivalent generator for the group. From the results of dynamic responses analysis conducted on the power system under study, it is observed that the dynamic equivalencing system is similar to the original system and can alleviate the computational burden needed for system dynamic studies.