Varying Rotation Speed Bearing Fault Features and Extraction Method Based on Wavelet Packet
When bearing rotates, it comes with elastic hydrodynamic lubrication effect. Interaction between the effect and the bearing vibration leads to the change of lubricant film thickness, thus, contact stiffness of contact pair changes along with the rotation speed of the bearing, and then the resonance frequencies of the bearing system changes according to the rotation speed. In addition, the impact signal of varying speed bearing damage point no longer has the periodic characteristics. Based on the analysis of the bearing failure mechanism, this paper proposed a varying speed bearing vibration signal fault model, and also utilizes wavelet packet to extract the bearing fault signal by means of a variable speed rolling bearing vibration experiment table.