循环域解调方法在滚动轴承故障诊断中的应用

讨论循环平稳信号的循环自相关函数特性，指出循环自相关函数不为零的循环频率对应着信号的周期成分。基于调幅和调频信号模型推导出循环域解调方法，通过扫描循环频率域使调制源(故障)信息解调在循环域的低频段和高频段。利用高频段无调制源交叉项的特点，对滚动轴承故障进行诊断，有效地提取出外圈、内圈和滚动体的故障特征。

Application of Cyclic Domain Demodulation in Fault Diagnosis of Rolling Bearing

The characteristic of cyclic autocorrelation function of cyclic stable signals has been discussed, some cyclic frequencies with nonzero cyclic autocorrelation function may correspond to periodic components of the signals. Based on the signal models of modulating amplitude and phase, the demodulation in cyclic domain has been developed. By scanning cyclic frequency domain, the modulating source signals can be demodulated in low and high frequency band of the cyclic domain. Using the characteristic of no-interactions among the modulators in high frequency band, the bearing faults are diagnosed, and the features of spalling on outer and inner raceway and flaking on rolling elements are extracted successfully.