Performance comparison of measurement microphones and microbarometers for sound pressure measurements near wind power plants

Abstract

Reliable assessment of airborne infrasound emitted by natural and technical sources has been gaining importance, while technology is limited and regulations are not sufficient in the infrasound frequency range. This paper provides a comparison of measurement microphones and microbarometers used for infrasound measurements in the field near wind power plants. Simultaneous measurements with both sensor systems were conducted at multiple sites in the vicinity of a wind park. Based on these measurements, it was shown that wind-induced noise is a major concern when measuring infrasound in the field. For this reason, additional experiments were conducted in an aeroacoustic wind tunnel to further investigate the sensitivity to wind of the sensors used. A combination of field measurements and laboratory experiments was applied to determine the influence of wind-induced noise in a real-life situation and multiple strategies are discussed for establishing quality criteria and controlling the influence of wind on such measurements.