Transient Fault Signal Detection Using Wigner Higher-Order Moment Spectra Methods

Most mechanical faults in machinery reveal themselves through transient events in vibration signals. That is, the vibration generated by industrial machines always contains nonlinear and non-stationary signals. Many analysis methods in current use are optimal for Gaussian and linear models but are suboptimal when the problem is one of analysing non-stationary, non-linear and non-Gaussian signals. Focusing on the defects of different joint time-frequency representations, the analysis of transient vibration signals is considered using Wigner higher-order based time-frequency distributions in this paper. The Wigner higher-order moment spectra (WHOS), which are the extensions of the Wigner-Ville distribution (WVD) to higher-order moment spectra domains, can describe the higher-order moment spectral characteristics from the time domain and the frequency domain simultaneously. The simulation case show that this technique has high time-frequency resolution and reduced interference terms