Effect of atmospheric stability on the wind resource extrapolating models for large capacity wind turbines: a comparative analysis of power law, log law, Deaves and Harris model

Abstract

Abstract To observe certain wind climate from the available met mast measured wind data at different heights an accurate wind shear model is necessary. Since WAsP and windPRO is software package which provides the better representation of wind profile over homogeneous terrain only. Though, a separate module named as WAsP CFD has been added in both of the software to predict correct wind resource in complex terrain also. Nowadays wind resource assessment has been widely dependent on terrain and becomes a key issue for the researchers. It has been found experimentally from earlier work that Deaves and Harris model shows a better representation of wind profiles on flat terrain at higher heights in comparison to other models such as the PL (power law), the LogL (log law) and the LogLL (Log-linear law). This study presents a comparative analysis of three different wind extrapolation models. Based on 2 year measured wind data from the met mast the at 10 m, 50 m, 80 m, 100 m and 102 m heights, results were compared in different stability classes using Monin-Obukhuv similarity theory. The RMSE (root mean square error) and NRMSE (normalized root mean square error were found to be least in case of log linear model which is 0.11 and 0.01784 respectively in compare to the PL and Deaves and Harris models.