Software assists quieting noisy turbine
Wind turbines occasionally get a bad rap for noise. At times, it’s not the turbine’s fault but rather an internal problem that amplifies the noise. For instance, a recent set of megawatt-scale wind turbines were emitting noise in the 800-830-Hz band. The manufacturer identified 820 Hz as the frequency at which the gear teeth mesh in the gearbox’s last stage. All conventional wind turbine gearboxes have gear-meshing frequencies but do not cause problematic noise, indicating the vibration was being amplified structurally. A vibration survey using a set of accelerometers identified the vibration pathway between the gearbox,nacelle, and tower walls.