改进阈值函数在振动信号降噪中的仿真研究  

Improved Threshold Function Simulation Research in Vibration Signal Denoising

作　　者：孙红星[1] 张洋[1] 

机构地区：[1]辽宁科技大学电子与信息工程学院,辽宁鞍山114051

出　　处：《系统仿真学报》2017年第8期1788-1794,共7页Journal of System Simulation

基　　金：国家自然科学基金(71472081)

摘　　要：有效滤除机械振动信号中的噪声干扰成分能够更明确地观察振动信号特征,因此在小波阈值降噪方法的基础上,提出一种改进的新阈值函数,该方法通过基于峭度值的阈值选取方法对机械振动信号经小波变换后的小波系数进行估计,新阈值函数不仅符合振动信号的分布特征,并且新阈值函数在阈值点处是连续的,克服了传统阈值函数所具有的固有偏差,通过对仿真信号以及实测机械振动信号的降噪处理研究,表明基于改进的阈值函数的小波降噪方法很好地保护了振动信号的有用信息,是一种有效的振动信号降噪方法。Filtering noise component of mechanical vibration signal effectively can observe the characteristics of vibration signal more clearly. So based on the wavelet threshold de-noising method, a new improved threshold function was proposed The coefficient of wavelet transform mechanical vibration signals were estimated by the threshold selection method based on kurtosis value. Not only new threshold function conforms to the distribution characteristics of the vibration signal, but also new threshold function is continuous in the threshold point. And the new threshold function overcomes the inherent deviation which traditional threshold function brings. The research of noise reduction on the simulation signal and measured mechanical vibration signal shows that wavelet de-noising method based on the improved threshold function protects the useful information of vibration signal well, and provides the method is a kind of effective de-noising method in vibration signal.

关 键 词：小波降噪 阈值函数 机械振动 故障诊断 

分 类 号：TP301.6[自动化与计算机技术—计算机系统结构]