摘要
齿轮泵的振动信号中含有大量噪声,在对其进行应用之前必须降噪处理。传统的小波阈值降噪法在信号的奇异点附近会产生振荡现象,为此研究了一种新的小波阈值函数,把新的阈值函数和平移不变量相结合,提出了改进小波阈值法的平移不变量降噪方法。该方法克服了软、硬阈值的缺陷,同时抑制阈值法降噪时产生的伪吉布斯(Pseudo-Gibbs)现象。利用该方法对仿真信号和实测齿轮泵振动信号进行降噪处理,并与小波软、硬阈值法及新阈值法进行了对比。结果表明:该方法具有更好的降噪效果,可应用于齿轮泵振动信号降噪处理。
The vibration signals of gear pump include much noise that must be eliminated before application. De- noising algorithm based on traditional wavelet threshold may produce discontinuities in singularity point of signal. A new wavelet threshold function was used against the shortcomings of soft and hard threshold function. An improved de-noising method was put forward by combining new threshold function and translation-invariant de-noising meth- od. The method can overcome the disadvantages of soft and hard threshold de-noising methods and suppress the Pseudo-Gibbs phenomena caused by threshold de-noising methods. The experimental results show that the present method has better de-noising effect than conventional threshold de-noising methods, and can be applied to denoise the vibration signal of gear pump.
出处
《机械科学与技术》
CSCD
北大核心
2013年第1期81-85,共5页
Mechanical Science and Technology for Aerospace Engineering
基金
国防预研基金项目(9140A27020309JB4701)
第二炮兵工程学院科技创新基金项目(XY2010JJB38)资助
关键词
齿轮泵
振动信号
小波阈值法
平移不变量
降噪
gear pump
vibration signal
wavelet threshold method
translation-invariant method
de-noising
