关键词: 希尔伯特振动分解, 端点效应, 滚动轴承, 故障诊断

Abstract: Due to end effect exists in Hilbert transform and low pass filtering of Hilbert vibration decomposition，an improved Hilbert vibration decomposition method is proposed. Mirror-symmetric extension method is adopted in signal preprocessing in Hilbert transform, low pass filtering and synchronous detection, and the end effect caused by Hilbert transform and low pass filtering was eliminated. Subsequently, instantaneous frequency obtained by Hilbert transform and low pass filtering process was regarded as reference frequency. Finally, several components with different amplitudes were obtained by using synchronous detection and iterative operation. The simulation signal and experiment data generated from roller bearing demonstrated that the proposed method has excellent performance in vibration signal decomposition and end effect suppression, and it can effectively diagnose the roller bearing defect appeared on inner and outer race. So it has certain practical engineering application value.

Key words: Hilbert vibration decomposition, end effect, roller bearing, fault diagnosis