Equivalent modeling of DFIG based wind farm using equivalent maximum power curve

Abstract

The single-machine equivalent model (SEM) is usually employed to represent the dynamics of wind farm, while the accuracy of SEM decreases with the increase of difference of the incoming wind speeds between each wind turbine in the wind farm. In order to improve the accuracy of SEM, an equivalent modeling method using power characteristics curve of the wind turbine is proposed in this paper. In this method, an equivalent maximum power curve (EMPC) is obtained, where the wake effect is taken into account. Using the EMPC, the calculation of equivalent wind speed is unnecessary during equivalent modeling of the wind farm. A wind farm with 9 wind turbines is built in Matlab, and simulations are carried out under wind fluctuation and grid fault to evaluated effectiveness of the proposed equivalent modeling method.