基于小波变换的故障诊断信号非平稳性分析从工程角度,解释小波变换的实际含义,并将其与传统的傅里叶变换分析方法作比较,通过比较两种基函数的时频窗,显示小波变换在时域和频域都具有局部化特性,并且运用可调的柔性窗可对高频、低频信号分别采取不同的尺度进行分析,特别适合于分析奇异性强的机械故障诊断信号。以旋转机械轴振动信号为仿真分析对象,以Daubieches5阶小波作为基小波,介绍了小波变换在故障诊断的信号非平稳性分析中的应用,并给出了奇异点检测和瞬态过程检测的仿真示例,体现了小波变换在故障诊断领域对非平稳信号的时域局部细节的刻划能力。Fromengineeringpointofview,practicalsignificationofwavelettransformationisexplainedandcomparedwithtraditionalFouriertransformation.Comparisonofthetime frequencywindowoftwofunctionindicatedcharacteriticofthetime-frequencylocationandthemultiple-scaleanalyzationofthewavetransformation.Baseonthat,theapplicationofwavelettransformationinfaultdiagnosistoanalysenonstationarityofrollerbearingvibrationsignalswithDaubiecheswaveetisintroduced.Andsimulationdemonstrationofsingularpointsinspectionandtransientinspectionispresented.Theresultsshowthatwavelettransformationcandepictlocationdetailintimedomainofnonstationarysignal