摘要
二进正交小波分解通过一组高、低通正交镜像滤波器,以二分频形式把信号分解到各个频段中,经验模式分解(EMD)具有类似性质。但由于分解原理间的差异,对同一信号有不同处理效果。以故障滚动轴承振动信号处理为例,对比分析两种方法的处理效果,表明对于旋转机械,由于故障信号往往表现为调幅形式,而且相互间具有不同的载波与调制波频率,EMD方法是以信号的真实物理意义实现自适应二分频分解,能完整保留各个调幅信号,二进正交小波变换严格按照数学意义分解信号,势必破坏调幅信号完整性,影响故障定位,对比处理效果,EMD提取故障特征频率的效果要比二进正交小波分解好。
The processing effects of EMD and binary quadrature wavelet decomposition are analyzed and contrasted with the vibration signals from the faulty rolling bearing.The analytical result indicates that the vibration signal in rotating machinery behaves in the form of amplitude modulation,and the frequencies of carrler wave and modulation wave are usually different from each other.The method of EMD can self-adaptively decompose signal in the form of dyadic frequency components based on authentic physical meaning of signal,therefore the decomposed result can reserve signal of amplitude modulation character completely.The decomposition by binary quadrature wavelet has perfect theoretical foundation,but it only can decompose signal based on mathematical meaning.The integrality of signal of amplitude modulation is destroyed usually,therefore,the faulty location can not be positioned correctly.The processing effect of EMD is generally better than that of binary quadrature wavelet transformation.
出处
《振动与冲击》
EI
CSCD
北大核心
2007年第6期52-55,共4页
Journal of Vibration and Shock
基金
国家自然科学基金资助项目(50405022)
关键词
经验模式分解
固有模式函数
模式混叠
正交镜像滤波器
empirical mode decomposition,intrinsic mode function,mode mixing,quadrature map filter
