k阶循环矩解调用于滚动轴承故障特征提取

Fault Feature Extracting for Rolling Bearing Based on kth-Order Cyclic Moment

针对滚动轴承早期故障诊断中故障特征信号提取问题,提出了一种基于k阶循环矩的故障特征信号解调方法。在循环矩理论基础上,首先分析了时变调幅信号的k阶循环矩解调原理和方法;讨论了k阶循环矩的频率特性;得出了k阶循环矩不仅能解调出调制频率,还能解调出载波频率的规律;给出了k阶循环矩的计算方法,并利用仿真信号验证了该方法的有效性;最后通过滚动轴承振动信号进行了分析。结果表明,该方法能有效提取滚动轴承早期故障特征,识别故障类型,具有较高的可信度。

An approach based on kth-order cyclic moment was presented to deal with the fault feature extracting of the rolling bearing in incipient fault diagnosis.Firstly,based on cyclic statistics theory,the demodulation characteristics of the kth-order cyclic moment for time-varying amplitude modulation signal was studied,and the frequency characteristics were discussed.It was pointed out that kth-order cyclic moment could demodulate out the modulation frequency information,and obtain the carrier wave frequency information,and then the calculation methods were given.The analysis of the simulated signal demonstrates that the kth-order cyclic moment has quite good demodulation ability.An experimental investigation was performed to enable an assessment of the accuracy level.The result shows that the method based on kth-order cyclic moment has excellent reliability to early recognition of bearing failure.