Spectral Response and Efficiency of a Gearbox - SEIG system involved in Wind Turbine Application

Wind turbine is among the renewable electrical energy sources, this source of electricity raises its importance from its continuity and its cleanliness. This justifies the importance of its reliability. In this way, gearbox of wind turbine must be monitored. In this paper, simulated wind system is implemented in laboratory, vibration and generator stator current are sampled from sensors and analyzed through FFT techniques. Resulting spectrums are investigated in order to characterize a healthy gearbox before introducing a tooth fault. Differences between theoretical and practical characteristic frequencies of the gearbox can affect the spectrums interpretation and consequently the diagnosis decision cannot be efficient. This difference is caused by losses in practical frequencies. The present work gives a formulation of the gearbox transmission efficiency to determine the origin of the losses in gearbox practical frequencies.