A survey of dynamic equivalent modeling for wind farm

With the increasing of grid connected wind power capacity, dynamic equivalent modeling for large wind farm have become more and more important as the tool to analyze the influence of power system stability with large-scale grid-connected wind farms. Recently doubly-fed induction wind generator (DFIG) has become the mainstream wind turbine used in wind farm for its virtue in wind power conversion efficiency and active power regulation activity. Thus, DFIG based wind farm has attracted more and more attention. This paper provided an overview of dynamic equivalent modeling for wind farm. At first, the structure of DFIG dynamic model, the principle and characteristic of each part are introduced. Secondly, various dynamic equivalent modeling methods for wind farm, including single-machine representation method and multi-machine representation method, are discussed in details. Meanwhile, the calculation methods for equivalent unit parameters for multi-machine representation based modeling are discussed. Finally the current researches and existing problems of the dynamic equivalent modeling for wind farm are summarized.