基于随机共振理论的低速重载设备故障诊断

基于随机共振理论，结合包络解调分析研究微弱低频幅值调制信号的增强与提取，并应用于低速重载设备的故障诊断.运用信号自含噪声或外加噪声，通过变步长数值算法和调节非线性双稳系统结构参数，来实现微弱低频幅值调制信号的随机共振现象.模拟调幅信号和实测低速重载齿轮箱振动信号的分析结果，证实了本文提出的方法在检测微弱低频幅值调制信号上，明显优于传统的FFT谱分析和包络解调方法.

Fault diagnosis of low-speed and heavy-duty equipments based on stochastic resonance theory

Enhancement and extraction of the weak low-frequency amplitude-modulated signal were studied using the combination of the stochastic resonance(SR) and envelope demodulation analysis,which was applied to the fault diagnosis of low-speed and heavy-duty equipments.The signal was firstly input into a nonlinear bistable system to realize the SR effect,which then was demodulated using the envelope analysis.The SR effect of the signal was realized based on the step-changed numerical algorithm and the adjustment of the bistable system parameters.Both simulated signals and real vibration signals of a low-speed and heavy-duty gearbox were presented to illustrate that the proposed method was superior to the spectra analysis and envelope demodulation methods in detecting the weak low-frequency amplitude-modulated signal.