Bearing Faults Diagnosis for Axle-Box of High Speed Train Based on Cepstrum Pre-Whitening and Envelope Demodulation

As the key load transfer component of high-speed train, axle-box bearing plays important role of load bearing, wear reducing and resistance. At present, it is a very effective method to monitor the bearing state by monitoring the vibration signal of the train axle-box online and adopting relevant methods. In this paper, a method of bearing fault diagnosis based on the combination of pre-whitening of cepstrum editing procedure (CEP) and envelope demodulation is proposed. The cepstrum pre-whitening can eliminate the periodic vibration component of the bearing vibration signal, extract the non-stationary impact vibration response of the bearing vibration signal containing noise, and analyze the envelope of the bearing vibration signal after pre-whitening to enhance the fault characteristic component in the case of the unknown optimal resonant frequency band. Through the data analysis and verification of the actual vehicle test-bed, this method can effectively diagnose the axle-box bearing fault, especially for the bearing inner ring and outer ring fault diagnosis.