LMD时频分析方法的端点效应在旋转机械故障诊断中的影响  

Research on End Effect of LMD Based Time-frequency Analysis in Rotating Machinery Fault Diagnosis

作　　者：任达千[1,2] 杨世锡[1] 吴昭同[1] 严拱标[1] 

机构地区：[1]浙江大学 [2]浙江机电职业技术学院

出　　处：《中国机械工程》2012年第8期951-956,共6页China Mechanical Engineering

基　　金：国家高技术研究发展计划(863计划)资助项目(2007AA04Z424);浙江省自然科学基金资助项目(Y1110582);浙江机电职业技术学院孵化基金资助项目(04090341)

摘　　要：为评估局域均值分解(LMD)受端点效应影响的程度,提出了一种基于能量的端点效应评价指标,并将LMD的端点效应与经验模态分解(EMD)的端点效应进行了比较。因包络线的定义方法不同,LMD在端点附近未定义的包络线较短,端点效应的程度也较轻。提出的端点效应镜像延拓抑制方法经仿真证明效果良好。将LMD应用于提取转子裂纹的故障特征,可获得满意的实验结果。An index was developed based on energy for evaluating the end effect of LMD.The end effects of LMD and EMD（empirical mode decomposition） were compared.Because the envelop definition was different,in LMD the undefined envelop near border was shorter than that in EMD.LMD end effect is not as seriously as EMD.A mirror extension method was developed to reduce the end effect.The simulation results are quite good.LMD is applied in cracked rotor diagnosis,and the experimental results are also quite good.

关 键 词：旋转机械 故障诊断 转子裂纹 局域均值分解 端点效应 

分 类 号：TH113.2[机械工程—机械设计及理论] TB533[理学—物理]