Defect detection of wind turbine gearbox using demodulation analysis

Wind turbine gearbox is one of the high failure rate components in wind turbine system, and various signal processing methods for vibration signals of gearbox to detect fault has obtained good results. In this paper, the structure characteristic of wind turbine gearbox is analyzed and the principle of defection modulation of gearbox vibration signals is studied. The method of cepstrum and Hilbert demodulation are used to analyze some field gearbox vibration data, and the two methods are compared. We can conclude that both cepstrum and Hilbert demodulation can extract the defection modulation frequencies in sophistication gearbox vibration signals, and Hilbert demodulation can detect defection more accurately than cepstrum. The Hilbert demodulation can be served as a good method to extract the defection characteristic in wind turbine gearbox.