Antifriction bearing VMD, spectral kurtosis and smooth iteration envelope analysis method

Abstract

The invention discloses an antifriction bearing VMD, spectral kurtosis and smooth iteration envelope analysis method. According to the method, firstly an original signal is decomposed by using a variational mode decomposition method; then the noise component and the trend term in the decomposition result are eliminated by using rearrangement and substitution operation of the data; then the signal after the first time of filtering is analyzed by using a spectral kurtosis method so that the center frequency and bandwidth of an optimal filter are obtained; then the second time of filtering is performed on the signal after the first time of filtering by using the filter; then envelope analysis is performed on the signal after the second time of filtering by using a smooth iteration envelope analysis method; and finally the fault type of an antifriction bearing is determined according to the envelope spectrum. The method is suitable for processing complex antifriction bearing fault signals and can accurately judge the fault type of the antifriction bearing so that the method has great anti-noise performance and robustness and is convenient for engineering application.

Description

technical field [0001] The invention relates to the field of state monitoring and fault diagnosis of rotating machinery, in particular to a VMD, spectrum kurtosis and smooth iterative envelope analysis method of a rolling bearing. Background technique [0002] Envelope analysis technique is widely used in fault diagnosis of gears and rolling bearings. The existing envelope analysis technology has the following three defects: ① The existing envelope analysis technology either directly analyzes the original signal, or only analyzes the original signal after simple filtering, so the existing method It is easily disturbed by noise, trend and other components, resulting in low analysis accuracy of the existing technology; ②The existing envelope analysis technology is based on the Hilbert transform, and the Hilbert transform requires that the signal to be analyzed must be a single component Narrowband signals, otherwise the frequency modulation part of the signal will pollute the...

AI Technical Summary

Problems solved by technology

The existing envelope analysis technology has the following three defects: ① The existing envelope analysis technology either directly analyzes the original signal, or only analyzes the original signal after simple filtering, so the existing method It is easily disturbed by noise, trend and other components, resulting in low analysis accuracy of the existing technology; ②The existing envelope analysis technology is based on the Hilbert transform, and the Hilbert transform requires that the signal to be analyzed must be a single component Narrowband signals, otherwise the frequency modulation part of the signal will pollute the amplitude envelope analysis results of the signal, but the current signals to be analyzed do not strictly meet the conditions of single component and narrowband, which will lead to the existing technology is easy to The problem of misjudgment occurs; ③The envelope spectrum obtained by traditional methods has endpoint effects

Images