Resonant-Frequency Band Choice for Bearing Fault Diagnosis Based on EMD and Envelope Analysis

This study presents a novel method based on the empirical mode decomposition (EMD) and the envelope analysis for the fault detection of rolling bearings. The main purpose is to overcome the traditional envelope method in the choosing of the resonant frequency band. First, the EMD method is adaptively to decompose the vibration signals into a series of the intrinsic mode function (IMF). Then, the decision of the resonant frequency band relies on the overlap frequency which compares the resonant frequency spectrum with the spectrum of each IMF. Finally, the interest of IMF is selected and executed the envelope analysis. Therefore, the envelope spectrum is obtained to diagnose the bearing faults. Two types of the rolling bearing fault, the outer-race fault and the inner-race fault, are analyzed by the presented method. The experimental results show that the proposed method can efficiently diagnose for the fault detection of the rolling bearing.