ELIMINATING WIND NOISE CONTAMINATION OF WIND TURBINE NOISE AMPLITUDE MODULATION RATINGS - FIRST VALIDATION

Microphone wind noise can corrupt outdoor measurements and recordings. It is a particular problem for wind turbine measurements because these cannot be carried out when the wind speed is low. Previous studies simulated the effect that microphone wind noise has on the accuracy of a proposed Amplitude Modulation (AM) metric and found that even relatively low wind speeds of 2.5 m/s errors of over 4 dBA can result. It has also been shown that a wind noise detection algorithm can automatically find uncorrupted sections of the recording, and so recover the true AM metrics. This paper shows first results on validating the simulation approach by applying the automatic detection to recordings from pairs of microphones mounted on an acoustic camera array in combination with the results from the AM rating method suggested by the Institute of Acoustics Amplitude Modulation Working Group.