往复机械特征频段信号的解调分解及其应用

Demodulation of the Vibration Signal of a Reciprocating Machine at Spectral Characteristic Band and Its Applications

提出了往复机械特征频段加速度信号的调幅调频模型 ,并基于此模型用标准解调法Hilbert变换法推导出了特征频段加速度信号的解调分解公式。分析和解调测试说明 ,提出的解调分解方法可成功地实现对特征频段加速度信号的解调分解。在往复机械诊断中的运用实例说明 。

When a component of a reciprocating machine is at fault, there often appear some differences at a wide frequency band, here called characteristic band, in frequency spectrum of the corresponding vibration acceleration. In order to better express the differences of the acceleration signal within the characteristic band, an amplitude modulation and frequency modulation (AMFM) model for the characteristic band acceleration signal is introduced, and on basis of the model, with Hilbert transform, the demodulation formula for the acceleration signal is presented. With some examples and tests, it was showed that the wide band acceleration signal could be successfully demodulated using the formula. With applications of the demodulation to the diagnosis of reciprocating machinery, it was showed the signal and parameter resulted from the demodulation were useful in the diagnosis.