Aggregated models of wind farms: Current methods and future trends

Wind power plants installation in the electrical power networks has been growing through the last years and a larger penetration is expected in the near future. Because of this, wind farm technologies will influence the power system behavior modifying its dynamics by reducing power systems global inertia. Hence, there is an increased interest and need to study the wind turbine farms behavior and their effects on the power system not only by researchers but also from transmission system operators. This paper describes the current modeling and aggregation methods for wind farms. Following a discussion of the different aggregation methods, including full aggregated model, semi aggregated model and multi machine model, an evaluation has been done to study the performance of each method in providing the entire response of the wind farm at the interconnection point with the grid under real wind speed profile and fault condition. Finally, the needs for further research and the challenges in the concept of wind farm dynamics and aggregation have been discussed.