Detecting wind turbine wakes with nacelle lidars

Wake Conference 2017

Held, D.P.^1,2 ; Larvol, A.^2 ; Mann, J.^1

Department of Wind Energy, Technical University of Denmark (DTU), Frederiksborgvej 399, Roskilde

4000, Denmark^1

Windar Photonics A/S, Helgeshoj Alle 16-18, Taastrup

2630, Denmark^2

关键词: Continuous Wave;    Detection capability;    Doppler spectra;    Horizontal homogeneity;    Improved controls;    Measurement campaign;    Small scale turbulence;    Wind turbine wakes;   

Others  :  https://iopscience.iop.org/article/10.1088/1742-6596/854/1/012020/pdf
DOI  :  10.1088/1742-6596/854/1/012020

来源: IOP

【 摘 要 】

Because the horizontal homogeneity assumption is violated in wakes flows, lidars face difficulties when reconstructing wind fields. Further, small-scale turbulence which is prevalent in wake flows causes Doppler spectrum widths to be broader than in the free stream. In this study the Doppler peak variance is used as a detection parameter for wakes. A one month long measurement campaign, where a continuous-wave lidar on a turbine has been exposed to multiple wake situations, is used to test the detection capabilities. The results show that it is possible to identify situation where a downstream turbine is in wake by comparing the peak widths. The used lidar is inexpensive and brings instalments on every turbine within economical reach. Thus, the information gathered by the lidars can be used for improved control at wind farm level.