基于HWPT-ZFFT的二维全息谱计算方法  

Research of 2-D Holospectrum Calculation Based on HWPT-ZFFT Method

作　　者：李纪永[1] 李舜酩[1] 陈晓红[2] 王勇[1] 

机构地区：[1]南京航空航天大学能源与动力学院,南京210016 [2]南京航空航天大学理学院,南京210016

出　　处：《振动．测试与诊断》2016年第1期68-72,198,共5页Journal of Vibration,Measurement & Diagnosis

基　　金：机械结构强度与振动国家重点实验室开放课题资助项目(SV2015-KF-01);中央高校基本科研业务费专项基金资助项目(NZ2015103)

摘　　要：精确的频率、相位和幅值识别是进行全息谱计算的必备条件,针对含3个及以上的密集频谱成分,提出一种基于谐波小波包变换的频谱细化方法(harmonic wavelet packets transform-zoom fast Fourier transform,简称HWPT-ZFFT),较传统的复调制细化傅里叶变换所利用的低通及带通滤波器相比,其盒型频谱特性可将感兴趣频段的信号正交,无冗余、无泄漏地提取出,提高了识别精度。首先,利用谐波小波包对密集频谱成分进行滤波;然后,频移进而重采样,进行傅里叶变换得到细化的频率、幅值及相位;最后,计算密集频率下二维全息谱,进行双盘转子全息谱计算,考虑高次分倍频,得到更丰富的故障特征。仿真及双盘转子实验结果表明所提出方法的有效性。A HWPT-ZFFT(harmonic wavelet packet transform and zoom fast Fourier transform)method is proposed for spectrum zoom,targeted for a spectrum that contains three or more intense frequency components.When the signals are orthogonally decomposed into different frequency bands with no redundancy or leakage,they perform better using the box-like spectrum instead of the tradition low-pass and band-pass filter in complex modulation ZFFT.First,the HWPT method is employed to filter the intense components,shift the center frequency to zero,and resample.Then,the frequency,amplitude and phase after zoom are obtained by FFT in order to calculate the holospectrum.Finally,rich fault characteristics are obtained under higher frequency.The effectiveness of this method is demonstrated through simulation and multi-span rotor system experimental results.

关 键 词：谐波小波包 密集频谱 频谱细化 全息谱 

分 类 号：V233.1[航空宇航科学与技术—航空宇航推进理论与工程] TH132[机械工程—机械制造及自动化]