Measurement of infrasound generated by wind turbine generator

This paper describes the development of a new sensor which uses a condenser microphone and a new system containing it as an element. The back of the microphone is covered with a seal chamber, which expands the frequency characteristic of the microphone to the infrasonic region. In addition, a windscreen is fitted to the sensor to reduce or eliminate wind noise. We developed a measurement system with this new sensor, installed it at a wind farm, and measured infrasound. The measurement results confirmed that the measurement system worked normally and could measure infrasound generated by wind turbines. Moreover, it was confirmed that the equivalent continuous sound level is highly correlated with the average rotor speed of a wind turbine.