改进的EMD消噪方法在交流接触器退化规律研究中的应用

Application of Improved EMD Denoising Method in the Study of Degradation Law of AC Contactor

针对交流接触器状态监测信号非线性、非平稳、强背景噪声等特点,提出了一种改进的经验模态分解(EMD)方法对影响交流接触器状态的主要参数进行消噪处理。首先将参数进行分解,得到一些相互独立的本征模态分量(IMF),其次计算各个IMF与原信号的互相关系数,保留互相关系数大的IMF分量,最后对保留分量中的高频分量进行小波阈值消噪。试验结果表明,改进后的EMD方法消噪效果优于单独使用EMD,是一种有效的消噪方法。

A cco rd in g to the characteristics o f n o n llin e a r, n o n -sta tio n a ry, and strong background noise in ACcontactor co n d itio n m o n ito rin g ,an im proved e m p iric a l mode decom position （ E M D ） m ethod was proposed fo rdenoising the m ain parameters w hich affect the state o f AC contactor. The m ethod is used firs t to param eterd e com po sition, get some independent in trin s ic mode com ponents （ I M F ） , then follow e d by ca lcu la tio n o f the crosscorrelation co e fficie n t o f each IM F and the o rig in a l s ig n a l, keep m u tual re la tionsh ip between a large num ber ofIM F s. F in a lly ,to preserve the high frequency com ponent to do wavelet threshold denoising. The experim ental resultsshow that the im proved e m p iric a l mode decom position m ethod is be tter than the single use o f E M D , and it is aneffective m ethod to elim in a te the noise.