基于同步挤压小波变换的结构瞬时频率识别

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振动与冲击 ›› 2013, Vol. 32 ›› Issue (18) : 37-42.

论文

基于同步挤压小波变换的结构瞬时频率识别

刘景良1，任伟新1,2，王佐才2，胡异丁1

作者信息 +

Instantaneous frequency identification based on synchrosqueezing wavelet transform

LIU Jing-liang1，REN Wei-xin 1,2，WANG Zuo-cai2，HU Yi-ding1

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文章历史 +

摘要

对结构响应信号采用连续可逆的时频变换工具—同步挤压小波变换，能提高时频曲线频率精度，有效地识别出结构的瞬时频率。用Duffing弱非线性系统及两层剪切型建筑模型验证该方法的正确性。设计时变拉索试验，分别对索施加线性与正弦变化拉力，测出结构的加速度响应，用同步挤压复Morlet小波变换算法进行索的瞬时频率识别。数值模拟及试验表明, 同步挤压小波变换能有效识别时变结构及非线性结构的瞬时频率，该方法具有较好的稳定性。

Abstract

A continuous and invertible synchrosqueezing wavelet transform is performed on a time-varying response signal and instantaneous frequency can be accurately identified as a result. The effectiveness and accuracy of the proposed method is validated via classical Duffing system and a numerical example of two-story shear building with two kinds of force vibration. Finally, a cable structure test is set up with linear and sinusoidal varying tensions respectively applied to the cable, which result in time-varying and nonlinear stiffness. Among three mother wavelet function, complex Morlet synchrosqueezing wavelet transform algorithm is introduced for instantaneous frequency identification. The results of numerical simulations and experimental test demonstrate that the method can extract the instantaneous frequency effectively and the choosing of mother wavelet function has little effect on instantaneous frequency identification.

导出引用

刘景良;任伟新;王佐才;胡异丁 . 基于同步挤压小波变换的结构瞬时频率识别[J]. 振动与冲击, 2013, 32(18): 37-42

LIU Jing-liang;REN Wei-xin;WANG Zuo-cai;HU Yi-ding. Instantaneous frequency identification based on synchrosqueezing wavelet transform[J]. Journal of Vibration and Shock, 2013, 32(18): 37-42