A Transient Faults Diagnosis Method Based on EEMD, Spectral Kurtosis Theory and Energy Operator Demodulating

Abstract

When an early fault turns up in rotating machinery, the normal vibration signal will be modulated with periodic transient shock pulses. It’s significant to diagnose these periodic shock pulses for early fault prognostic and diagnostic tests. Usually demodulating is one of the most effective and common used method. Because of the strong background noise, it’s very difficult to select the parameters of band-pass filter. In this paper, we propose to use Ensemble Empirical Mode Decomposition (EEMD) coordinating with spectrum kurtosis theory to choose the Intrinsic Mode Functions (IMFs) to reduce the background noise and select the parameters of band-pass filter adaptively by fast-kurtogram. Energy operator demodulating method is used to demodulate the rebuilt signal to identify the faults frequencies. Energy operator demodulating displays better accuracy and little edge error. The achieved accuracy in the simulation indicates that this proposed transient faults diagnosis method is highly reliable and applicable in early transient faults diagnosis of industrial rotating machinery.