机械变速过程的瞬时参数与频谱分析

Instantaneous Parameters and Spectrum Analysis in Mechanical Speed-Change Process

为提高机械变速过程中振动信号分析的准确性,通过分析旋转机械的变速测量过程,建立了变速测量方式与信号时变统计特性之间的非线性变换关系,并引入希尔伯特变换确定信号的瞬时参数.结果表明,根据信号的瞬时频率对测量信号进行内插处理,可以消除因变速引起的信号频谱的畸变,准确反映振动信号的频谱特征.

To enhance the analytical accuracy of vibration signals in a mechanical speed-change process, a non-linear relationship between the measurement systems of speed-change and the time varying statistic characteristics of the signals was established by analyzing the measurement process for a rotating machine. The Hilbert transform was applied to give the expression of instantaneous parameters of the signals. The research shows that the aberration of frequency spectra induced by the change of speed can be avoided when measured signals are dealt with through interpolation in light of the instantaneous frequency to gain the frequency spectra of vibration signals.