改进双树复小波变换和高阶累积量的齿轮箱信号降噪方法  

Gearbox Signal Denoising Method Based on Improved Double Tree Complex Wavelet Transform and Higher Order Cumulant

作　　者：陈旭阳 韩振南 王志坚 CHEN Xuyang;HAN Zhennan;WANG Zhijian(College of Mechanical and Vehicle Engineering,Taiyuan University of Technology,Taiyuan 030024,China;School of Mechanical Engineering,North University of China,Taiyuan 030051,China)

机构地区：[1]太原理工大学机械与运载工程学院,太原030024 [2]中北大学机械工程学院,太原030051

出　　处：《太原理工大学学报》2018年第6期813-819,共7页Journal of Taiyuan University of Technology

基　　金：国家高技术研究发展计划863计划资助项目(2012AA06A405);国家自然科学基金资助项目(50775157);山西省基础研究计划资助项目(2015011061)

摘　　要：采用传统阈值降噪方法对小波系数分别进行软、硬阈值处理时在强背景噪声下提取的齿轮箱故障振动信号效果不理想,且实、虚部分离的阈值处理方法会引起局部相位失真。利用双树复小波变换的平移不变性,提出了双树复小波变换和高阶累积量的齿轮箱振动信号降噪方法。对分解和单支重构后的各双树复小波系数采用了四阶累积量的处理方法,根据信号和噪声的统计特性进行信噪分离。由于小波分解层数会直接影响信号的去噪效果,因此,采用粒子群算法优化小波的分解层数。仿真和实验信号处理结果表明:该方法与双树复小波变换的软、硬阈值处理方法相比,在不同信号和噪声水平下更能有效地抑制噪声干扰,提高信噪比,并且能够满足实验中对采集到的振动信号进行特征提取的需求。For traditional threshold denoising method,the effect of the fault signal of gearbox extracted from the background noise under soft background and soft threshold is not ideal,and the threshold processing method of the real and imaginary parts causes local phase distortion.On the basis of the translation invariance of double-tree complex wavelet transform,a method of noise reduction of double-tree complex wavelet transform and high-order cumulant is proposed.The algorithm uses the fourth-order cumulant processing method for each dual-tree complex wavelet coefficient after decomposition and single reconstruction,and carries out signal-noise separation according to the statistical characteristic of signal and noise.Because the number of wavelet decomposition layers directly affects the denoising effect of signal,the particle swarm optimization algorithm is used to select the number of decomposed layers of wavelet.The simulation and experimental signal processing show that this method can effectively suppress the noise interference and improve the signal-to-noise ratio at different signal and noise levels compared with the soft and hard threshold processing methods of double-tree complex wavelet transform,and satisfy the feature extraction need for subsequent processing of collected experiment vibration signal.

关 键 词：双树复小波变换 高阶累积量 齿轮箱 粒子群算法 降噪 

分 类 号：TN911.72[电子电信—通信与信息系统] TP206[电子电信—信息与通信工程]