Abstract
The nacelle-mounted LiDAR has been attracted as the wind measurement instruments for the evaluation and the advance control of the wind turbines. Nacelle-mounted LiDAR can measure the wind speed in front of the turbine using the Doppler effect of the laser pulse. Using the measured forward wind speed, the inflow wind speed could be estimate more exactly than existing methods like an anemometer on the nacelle or of the metrological mast. However, it is reported the inflow wind slow down as the wind approaches the wind turbine, called Blockage effect, by the model experiments and the CFD simulations, affected by blades of the turbine. Moreover the wind measurement precision nacelle-mounted LiDAR could be affected by the yaw angle of the turbine since the LiDAR is attached on the turbine and the yaw angle of the LiDAR is connected with that of the turbine. In this paper, the blockage effect and the influence of the yaw error on the wind measurement was investigated using the measurement wind data by the nacelle-mounted LiDAR. The blockage effect was confirmed and made good agreement with the results of the model experiments and the CFD simulations. It is verified that the yaw error of the turbine also affected the wind measurements.
