摘要
汽蚀现象是导致水泵效率和使用寿命降低的主要原因之一。快速准确的诊断并排除汽蚀故障,使水泵正常运行,具有重要的意义。本文根据离心泵入口压力脉动信号的特点,提出一种基于EMD能量熵的汽蚀故障诊断方法。该方法首先应用提升小波,对原始信号进行阈值去噪处理,然后将处理后的信号进行EMD分解,计算其能量熵,并以能量熵作为离心泵汽蚀故障识别的判断依据。试验结果表明:在不同的有效汽蚀余量(NPSH)下,压力脉动信号的EMD能量熵值明显不同,因此可以将其作为一种有效的特征参数来表征不同的汽蚀工况。
Cavitation phenomenon happens in pump is one of the major causes which leading to the reduction of efficiency and service life.Fast and exact fault diagnosis and removal is very importance to ensure the pumps＇ normal operation.A method that based on energy entropy of empirical mode decomposition（EMD） was proposed according to the characteristic of the pressure fluctuation signal of the centrifugal pump inlet.Firstly the original signal was de-noised by using lifting wavelet,and then EMD method was applied to compute the value of the energy entropy of EMD.The energy entropy was viewed as a judgement to recognize cavitation fault.The experimental result shows that the values of energy entropy of EMD are different obviously in different net positive suction head（NPSH） states.It can be regarded as an effective characteristic parameter to measure different cavitation states.
出处
《化工自动化及仪表》
CAS
北大核心
2010年第5期41-46,共6页
Control and Instruments in Chemical Industry
基金
吉林省教育厅"十一五"科学技术研究项目(200747)
关键词
汽蚀
故障诊断
压力脉动
提升小波
EMD能量熵
cavitation
fault diagnosis
pressure fluctuation
lifting wavelet
energy entropy of EMD
