IESCFFOgram

Improved Envelope Spectrum via Candidate Fault Frequency Optimization-gram for Bearing Fault Diagnosis.

A feature-adaptive method called Improved Envelope Spectrum via Candidate Fault Frequencies Optimization-gram (IESCFFOgram) is developed to identify the informative spectral frequency band from Spectral coherence(SCoh) for bearings fault diagnosis. In the new method, the candidate fault frequencies (CFFs) instead of the nominal fault characteristic frequency (FCF) are automatically identified based on the local features of the SCoh and further used to guide the selection of the informational band. This new method completely gets rid of the dependence on FCF or sparsity indicators and can adaptively generate diagnostic IES by excavating the fault information hidden in the SCoh plane. Therefore, the proposed IESCFFOgram is suitable for the fault identification of rolling bearings when accurate FCFs are not available.