Short-Term Power Fluctuation of Wind Turbines: Analyzing Data from the German 250-MW Measurement Program from the Ancillary Services Viewpoint

Short-term power fluctuations from wind farms may affect interconnected-grid operating costs and stability. With the increasing availability of wind power worldwide, this has become a concern for some utilities. Under electric industry restructuring in the United States, the impact of these fluctuations will be evaluated by examining provisions and costs of ancillary services for wind power. However, the magnitude of the impact and the effect of aggregation of multiple turbines are not well quantified due to a lack of actual wind farm power data. This paper analyzes individual turbine and aggregate power output data from the German ''250-MW Wind'' data project. Electric system load following and regulation impacts are examined as a function of the number of turbines and turbine spacing in order to quantify the impacts of aggregation. The results show a significant decrease in the relative system regulation burden with increasing number of turbines, even if the turbines are in close proximity.