耦合双稳系统随机共振的轴承故障检测方法

耦合双稳系统由两个双稳系统经非线性方式耦合而成.分析了影响耦合双稳系统随机共振产生的Kramers逃逸率及平均跃迁频率与耦合系数的关系,提出了通过调节耦合系数大小来产生和增强随机共振的方法,并将该方法应用于轴承故障信号检测中.数值仿真和实验结果表明,在系统参数固定时,调节耦合系数能增强系统输出功率谱在特征频率处的谱值,可检测出单一双稳系统随机共振所不能检测出的微弱轴承故障信号频率,该方法在轴承故障信号检测中的应用是有效的.

Detection of bearing fault signals based on coupled bistable system stochastic resonance

The coupling system is composed of two single bistable systems by means of nonlinear coupling. The relationship between the coupling coefficient and the Kramers rate along with average transition frequency which affected stochastic resonance was analyzed. A novel method of controlling and enhancing stochastic resonance by adjusting the coupling coefficient was proposed and applied to the detection of bearing faults. Numerical simulations and experimental results show that, when the system parameters were fixed, the spectral power output of the coupled systems at the weak periodic signal frequency could increase greatly by changing the coupling coefficient and that it could detect the weak signals of bearing faults effectively while the single bistable system could not. The method is feasible and effective in the detection of bearing faults.