Research on Equivalent Accuracy of Wind Farm Composed of DFIGs

To measure the effect of the equivalence of wind farm composed of double fed induction generators(DFIGs), a method to assess the accuracy of equivalence of such a kind of wind farm is proposed. Based on direct distance method, standard coefficient method and fuzzy analytic hierarchy process(AHP), from two aspects of numerical evaluation and trend evaluation the proposed method performs synthetic quantitative evaluation on different states and multi indices of the wind farm. Firstly, utilizing the weighted average method combining the principle of constant voltage drop with the principle of equivalent power loss, the equivalence of the variable speed constant frequency doubly fed wind power generation units and the collector system are correspondingly carried out. And then the detailed and the equivalent model of the wind farm are constructed respectively to conduct syn-thetic and quantitative evaluation on the equivalent accuracy of the wind farm. Using the proposed method, the equivalent accuracy of the wind farm can be reasonably evaluated, besides, according to the evaluation result, the equivalent model can be modified to improve the equivalent accuracy of the wind farm.