The invention discloses a phase modifier bearing fault diagnosis method, which belongs to the technical field of
power equipment fault diagnosis, and comprises the following steps of: analyzing independent components, performing blind
source separation on a received phase modifier
bearing vibration signal, and extracting three types of independent source signals of
impact, abrasion and
noise; the gradient driving window length is self-adaptive, and the window length of short-time
Fourier transform is dynamically adjusted based on the instantaneous frequency gradient of the independent source
signal;
wavelet packet
frequency band energy screening: performing
wavelet packet
decomposition on the
signal after window length adaptive
processing, screening a fault characteristic
frequency band based on an energy contribution rate, and reconstructing the signal; and enhancing
stochastic resonance, and inputting the reconstructed signal into a
stochastic resonance system. According to the method,
independent component analysis, gradient driving window length self-adaption,
wavelet packet
frequency band energy screening and
stochastic resonance enhanced fourth-order diagnosis chain are constructed, so that multi-stage cooperative
processing of phase modifier bearing faults is realized, and the technical problems of time-
frequency resolution contradiction, insufficient feature decoupling and weak generalization ability are effectively solved.