The Research of Higher-order Cumulant Spectrum for Vibration Signals of Gearbox

Abstract

In the fault diagnosis of gearbox, the extraction of the characteristic currently, usually suppose that vibration signal fault signal is a key problem. The practical testing vibration is acquired on constant duty and unchanged circumstance, and signal of gearbox is no stable or Gauss distributing. In different have the characteristic of stability and Gauss distributing. In fault states, the vibration signal has different Gauss property and fact, in engineering, much mechanical equipment usually runs symmetry property, usually including stronger noise and low '' .SNR. Faint fault information is often totally flooded in the noise, n siftion anar duty. So th practi eca nical, so it is very difficult to extract the signal characteristic. Because viatio sign mostly blns to non-stead si signal's Higher-order cumulant is not sensitive to the adding especially even more like this while breaking down, but just Gauss noise and symmetry non-Gauss noise, if applied in the stability under meeting certain special condition fault diagnosis of the gearbox, it can separate signal and noiseIn the fault diagnosis of gearbox, the extraction of the fault effectively, improve the SNR and intensify fault information.signal is a key problem. The practical testing vibration signal Based on the contrast and analysis of the vibration signal of some of gearbox is no stable or Gauss distributing. In different fault second gearbox under different states, this paper has extracted states, the vibration signal has different Gauss property and the power spectrum and Higher-order cumulant spectrum symmetry property, usually including stronger noise and low (bispectrum) of the gear vibration signals, has set up the SNR. Faint fault information is often totally flooded in the characteristic vector of bispectrum used in fault diagnosis. The noise, so it is very difficult to extract the signal characteristic.analysis result shows that, compared with power spectrum, the Two-order cumulant spectrum (the power spectrum) is the characteristic extracting from the Higher-order Cumulant commonly analysis method of gear fault signal. The frequency spectrum is more sensitive to the fault characteristic, and easy to spectrum difference of vibration signal under the normal and realize the digital characteristic extracting in the intelligent fault state can distinguish the working state of gearbox, thus diagnosis, can identify the fault of gearbox effectively, the fault can be diagnosed. Theoretically, the power spectrum Keywords: gearbox, vibration signal, Higher-order cumulant of the signal is sensitive to the colored noise; it can't offer the spectrum. effective means to separate the primitive signal and noise. Xu Jinwu, etc. take use of the method of matrix fantastic spectrum 1. INTRODUCTION characteristic of reconstruct attractive particle orbit and wavelet transform to reduce the noise, so the fault As a kind of shifting and power transferring common characteristic of vibration signal is intensified [2,3]. While this equipment, because of its compact stru...

Fault detection and diagnosis of a gearbox in marine propulsion systems using bispectrum analysis and artificial neural networks

“…As a result, in theory, the bispectrum can restrain noise entirely to extract useful information (Huang et al, 2006).…”

“…The bispectrum has been proven to be effective in this situation. It can capture characteristic frequency, identify the phasic information and express nonlinear advantages (Huang et al, 2006). A brief description of bispectrum is as follows.…”