发动机变速阶段振动信号时频分析阶比跟踪研究

发动机变速过程产生的振动复杂多样,具有周期性和频率倍增等特点。阶比跟踪是一种用于旋转类机械系统动态设计、故障诊断和状态监测的重要方法。阐述了阶比跟踪的国内外发展及技术情况。G abor变换是一种可逆的联合时频变换,通过研究G abor变换及满足信号时域重构的对偶函数双正交条件,采用在时频域进行带通滤波的方法来进行阶比跟踪,能够得到各阶比成分的时域重构信号。克服了采用传统等角度重采样后进行傅立叶变换方法不能在时域内提取阶比信号的不足。

Study of time-frequency order tracking of vibration signals in engine speed changing stage

Vibration is complicated and diversified in varying speed process of engine,and has characteristics of periodicity and multiple frequency.Order tracking is an important method for dynamic design,fault diagnosis and condition monitoring in rotating machinery.Gabor transform is a reversible joint time-frequency transform.Gabor transform and time reconstruction biorthogonal condition are studied and presented in this paper.Order tracking is implemented by band pass filter in time-frequency domain and time signal of desired order is reconstructed.Time-frequency order tracking method overcomes the shortcomings of traditional resampling and FFT methods.