变步长频率加权能量算子在轴承故障诊断中的应用  

Application of variable step frequency weighted energy operator in bearing fault diagnosis

作　　者：刘泽潮[1] 林建辉[1] 丁建明[1] 吴文逸 LIU Zechao;LIN Jianhui;DING Jianming;WU Wenyi(State Key Laboratory of Traction Power,Southwest Jiao Tong U niversity,Chengdu 610031,China)

机构地区：[1]西南交通大学牵引动力国家重点实验室,成都610031

出　　处：《振动与冲击》2019年第7期86-92,共7页Journal of Vibration and Shock

基　　金：国家自然科学基金(51305358);国家重点研发计划先进轨道交通重点专项(2017YFB1201004)

摘　　要：通过包络解调可以提取调制信号中的周期成分来实现轴承故障的早期诊断与预警。但在进行包络解调时,需要解调信号必须为单调幅调频信号,且解调效果容易受到其他干扰信号的影响。频率加权能量算子较包络解调具有更高鲁棒性,但频率加权能量算子在离散化时使用的中点平均差分方法对中心频率较低的调制信号进行解调时鲁棒性较差。因此变步长频率加权能量算子通过改变步长参数来增强其在中心频率较低时的鲁棒性。通过分析与试验验证表明,变步长频率加权能量算子在整个频带都具有较好的解调效果。变步长频率加权能量算子可以在信号未经分解的前提下实现不同共振频带的解调,所以具有更强的工程应用价值。Envelope demodulation can be used to extract periodic components in modulated signals to realize early diagnosis and warning of bearing faults, but the envelope demodulation requires that the signals to be demodulated must be Am-FM signals, and the demodulation effect is easily affected by other interference signals. The frequency weighted energy operator is more robust than the envelope demodulation. However, the frequency weighted energy operator used to demodulate modulated signals with lower central frequency is less robust when the middle point average difference method was applied in discretization. Here, the variable step frequency weighted energy operator(VFWEO) was proposed to enhance its robustness at lower central frequency by changing step parameters. Analysis and test verification showed that VFWEO has a better demodulation effect within the entire frequency band;VFWEO can be used to realize demodulation of different resonant frequency bands without decomposing signals, so it is more valuable in engineering application.

关 键 词：滚动轴承故障诊断 频率加权能量算子 变步长差分 

分 类 号：H165.3[语言文字—汉语]