【摘要】 不同类型的机械故障在振动信号中会反映出不同的波形特征 ,选用不适当的小波基函数会冲淡故障的特征信息 ,给故障诊断造成困难。第二代小波变换可以通过设计预测系数和提升系数获得具有某种特性的小波基函数。本文介绍了第二代小波变换的原理 ,研究了预测系数和提升系数与低通和高通滤波器系数之间的关系 ,根据信号的特征构造了基于插值细分方法的双正交小波 ,在旋转机械的轴系不对中故障诊断中取得了满意的效果。更多还原

【Abstract】 Different wave features for different machinery faults are reflected in vibration signal, but an improper wavelet basis function for vibration signal can blur the informationof fault features and make diagnosis difficult. In the second generation wavelet transform(SGWT), wavelet basis function with some special characteristiccan be obtained by means of designing prediction and update coefficients. In this paper, the principle of SGWT is described, and the relationship among the prediction coefficients, the update coefficients and the coefficients of low-pass and high-pass filter is discussed. According to the feature of a given signal, a biorthogonal wavelet is constructed which is based on interpolating subdivision scheme, good results are obtained for shaftingfault diagnosis in rotatingmachinery.更多还原