Modelling of Turbulence Effect on Wind Turbine’s Power Curve

19721212

Abstract:
6 n" T9 K/ X( h: `To evaluate a wind turbine Power Curve -understood as the average of the electrical power variation with wind speed during a 10 minute period- it is necessary to consider the turbulence phenomenon.
In this way, a statistical methodology to generate Power Curves considering the effect of the turbulence is proposed. The validation of this methodology is performed against measurements of several pitch regulated wind turbines. Finally, the proposed methodology is used to carry out a study that reveals the importance of taking into account the turbulence of a specific site in the Power Curve and Annual Energy Yield evaluations.
Keywords: Turbulence Intensity, Power Curve, Annual Energy Yield, probability distribution, BEM theory
1. Introduction
3 `& s6 U& _; z0 F9 y# T  I3 G, K- dThe Power Curve of a wind turbine is defined as the variation of electrical power with wind speed. Both the electrical power and the wind speed correspond to the average measured value during a 10 minute period.
4 ]6 o+ U# r& e. |Due to this average treatment, the Power Curve of a wind turbine cannot be treated as static, but must take into account the wind speed short-term fluctuations during this 10 minute period. The variations of wind speed during this time are a consequence of the turbulence.
The main interest in understanding and reproducing the effect of the turbulence lies in foreseeing with high accuracy the Power Curve and the Annual Energy Yield of a wind turbine located at a specific site and, thereby, reducing the uncertainty of their prediction.
Thus, the objective of this paper is to establish a methodology to allow the characterization of the turbulence and determine its effects on a wind turbine Power Curve.
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