A Turbulence Intensity Similarity Distribution for Evaluating the Performance of a Small Wind Turbine in Turbulent Wind Regimes

Abstract

Field tests on a Skystream wind turbine in a turbulent environment were used to study the impacts of turbulence intensity on power performance. The objective of the study was to examine the influence of turbulence intensity on the deviations in power output from their published power curves, commonly experienced by small wind turbines, such that more accurate predictions in performance can be made for future small wind projects. One-minute averaged data was used to explore the distribution of turbulence intensities experienced in several wind speed bins. It was found that the resulting turbulence intensity distributions have a similar distribution across these wind speeds and thus it was compared to four common statistical distributions. A goodness of fit study was conducted finding a gamma distribution was the best fit. This finding constitutes a more elegant approach to empirically adjusting power curves for turbulence intensity than has been suggested by previous studies.