分析了航空发动机转子碰摩故障振动信号的基本特征,提出了故障信号瞬时频率诊断方法。运用解析小波将故障信号变换到小波域,利用小波系数的振幅和相位信息综合确定瞬时频率,根据瞬时频率的特征诊断故障,并对比了故障信号瞬时频率诊断方法与窗口Fourier变换方法故障诊断结果。数值分析结果表明:利用瞬时频率诊断方法提取碰摩信号的瞬时频率比利用窗口Fourier变换得到的结果更精细,并可获得用短时Fourier变换无法得到的一些瞬时频率曲线。
The basal characteristics of impact-rub fault signal for aeroengine rotor were analyzed,and a fault diagnosis method based on the instantaneous frequency of the fault signal was presented.The fault signal was transformed into wavelet domain by using wavelet transform,the instantaneous frequencies were extracted by using the amplitude and phase of wavelet coefficients,the fault was diagnosed by using the characteristics of the instantaneous frequencies,and the diagnosis results of the fault signal gained by using the proposed method and windowed Fourier transform were compared.Comparison result shows that the instantaneous frequency gained by using the proposed method is more precise and comprehensive.4 figs,6 refs.