Diagnosis method of instantaneous frequency for rotor impact-rub fault of aeroengine

The basal characteristics of impact-rub fault signal for aeroengine rotor were analyzed, and a fault diagnosis method based on the instantaneous frequency of the fault signal was presented. The fault signal was transformed into wavelet domain by using wavelet transform, the instantaneous frequencies were extracted by using the amplitude and phase of wavelet coefficients, the fault was diagnosed by using the characteristics of the instantaneous frequencies, and the diagnosis results of the fault signal gained by using the proposed method and windowed Fourier transform were compared. Comparison result shows that the instantaneous frequency gained by using the proposed method is more precise and comprehensive. 4 figs, 6 refs.