Analysis of wind farm dynamics using multiple doubly fed induction generators

In transient stability analysis, detailed model consisting of hundreds of wind turbines requires an excessive amount of computation. This computation and complexity demands a reduced equivalent model to facilitate the investigation of the impact of a wind farm on the dynamics of the power system to which it is connected. Although few approaches have been developed in aggregating wind turbines, the accuracy of the developed models may not be adequate because aggregation of nonlinear subsystems in a group is inevitably approximate and has to be quantified. This research presents a new mathematical approach of a simplified, reduced order approximate model derived from the aggregation of wind turbines. The effectiveness of the approximate model is demonstrated in an open-loop numerical analysis by comparing the dynamic response of the approximate model with a detailed multi-machine model. Stochastic variation is taken into account for the case studies performed.