Early Fault Diagnosis of Bearings Based on Improved Variational Mode Extraction
To overcome the difficulty in determining the initial center frequency of variational mode extrac-tion(VME)under strong background noise,a rolling bearing fault diagnosis method based on spectral co-herence-guided variational mode extraction(SC-VME)was proposed.First,a spectral coherence(SC)al-gorithm was introduced to process the signal to obtain the dual frequency domain consisting of cyclic fre-quency and spectrum frequency,and an improved envelope spectrum(IES)was obtained by combining 1/3-binary tree filter banks.Then,taking the proportion of local characteristic energy of bearing fault char-acteristic frequency recognition and IES energy in frequency band as diagnostic indexes,a diagnostic indica-tor diagram was constructed to determine the initial center frequency of VME expected mode.Finally,early fault diagnosis of rolling bearing is realized by envelope spectrum analysis of extracted expected mode.The results of simulation and experimental signal analysis show that the proposed SC-VME method has higher accuracy,shorter time and better effect.
rolling bearingsspectral coherencevariational mode extractionearly fault diagnosis
NETL
NSTL
万方数据
维普
