Using Spectrum Correction to Diagnose Mechanical Fault

Abstract

To diagnose the mechanical fault diagnosis from the rotation records, FFT and all-phase FFT (apFFT) are introduced to estimate the individual harmonics’ frequency, amplitude and phase of fault signal. Through introducing with synthesized FFT/apFFT correcting method of phase difference, the frequency and amplitude estimation can be obtained by utilizing these two spectral analysis results at the position of peak spectral line. Moreover, for apFFT possess the merit of phase invariance, the phase value at main spectral position can be directly taken as the original phase without any correcting operations, thus, waveform reconstruction is realized. Simulation experiment proves that fault information can be intuitively reflected by the quality of reconstructed waveform, and the corresponding type of mechanical fault based on parameters estimation can be identified.