Detecting rub-impact fault of rotor system based on variational mode decomposition

Abstract

Multi-component extraction is an available method for fault vibration signal analysis of rotary machinery, so a new method for rubbing fault diagnosis based on variational mode decomposition (VMD) is proposed. VMD is a newly developed technique for adaptive signal decomposition, which can non-recursively decompose a multi-component signal into a number of quasi-orthogonal intrinsic mode functions. VMD is then first applied to detect multiple rubbing-caused signatures for rotor-stator fault diagnosis via numerical simulated response. A comparison has also been conducted to investigate the effectiveness of monitoring the rubbing-caused signatures by using VMD, empirical wavelet transform (EWT), EEMD and EMD. The analysis results of the rubbing signals show that the multiple features of these signals can be efficiently extracted with the VMD.