Spectral envelope-based adaptive empirical Fourier decomposition method and its application to rolling bearing fault diagnosis

• Published in: ISA transactions 2022-10, Vol.129, p.476-492
• Main Authors: Zheng, Jinde, Cao, Shijun, Pan, Haiyang, Ni, Qing
• Format: Article
• Language: English
• Subjects: Adaptive empirical Fourier decomposition; Empirical wavelet transform; Fault diagnosis; Rolling bearing; Spectral envelope
• ISSN: 0019-0578; 1879-2022
• DOI: 10.1016/j.isatra.2022.02.049

Adaptive empirical Fourier decomposition (AEFD) is a recently developed approach of nonstationary signal mode separation. However, it requires to set the spectrum segmentation boundary relying on the users’ professional experience ahead of time. In this paper, a novel spectral envelope-based adaptive empirical Fourier decomposition (SEAEFD) method is proposed to improve the performance of AEFD for rolling bearing vibration signal analysis. In the proposed SEAEFD approach, fast Fourier transform (FFT) of the raw signal is calculated to obtain the frequency spectrum at first. Then, the spectral envelope processing is implemented on the spectrum signal obtained by FFT to achieve an adaptive segmentation. In the traditional segmentation method, generally, the minima and midpoints between adjacent extreme points are taken as the spectrum segmentation boundary, in which the obtained frequency band contains more interference components. To achieve the effect of denoising and restrain the noise that existed in the collected vibration signal, SEAEFD is proposed to optimize the spectrum segmentation boundary so that the obtained frequency band contains the least noise components. Lastly, the inverse FFT is used to reconstruct the component signal within each frequency band and the gained signals are termed as Fourier intrinsic mode functions (FIMFs). Therefore, SEAEFD enables a nonstationary signal to be decomposed into several single-component signals with instantaneous frequencies of physical significance. The proposed SEAEFD method is compared with recently developed methods, including EAEFD, AEFD, EWT, VMD and EMD methods, by analyzing the simulation signals and the measured data of rolling bearing. The results indicate that SEAEFD is valid in diagnosing rolling bearing faults and gets a better diagnosis performance than the compared methods. •The envelope processing-based spectrum segmentation method is developed.•A novel nonstationary signal decomposition method termed SEAEFD is developed to improve the performance of AEFD.•SEAEFD is compared with AEFD, EAEFD, EWT, VMD and EMD through analyzing the simulated and measured signals.•The effectiveness and superiority of SEAEFD in identify the local faults of rolling bearing are verified.