Pressure fluctuation analysis of axial-flow pump based on local mean decomposition

Asian Working Group- IAHR's Symposium on Hydraulic Machinery and Systems

Pan, H.^1 ; Zhang, F.^2 ; Zheng, Y.^1

College of Energy and Electrical Engineering, Hohai University, Nanjing, China^1

Technology Center, State Grid Xinyuan Company Ltd., Beijing, China^2

关键词: Characteristics of pressures;    Empirical Mode Decomposition;    Instantaneous frequency;    Local mean decomposition (LMD);    Local mean decompositions;    Multicomponent signals;    Time frequency analysis;    Time-frequency resolution;   

Others  :  https://iopscience.iop.org/article/10.1088/1755-1315/163/1/012124/pdf
DOI  :  10.1088/1755-1315/163/1/012124

来源: IOP

【 摘 要 】

Pressure fluctuation is inevitable in the operation of pumps. With an axial-flow pump as example, a new method for time-frequency analysis based on local mean decomposition (LMD) method was proposed to make a research on the characteristics of pressure fluctuation. LMD method is a self-adaptive method, by which any complicated multi-component signal could be decomposed into a number of product functions (PFs) whose instantaneous frequencies have physical significance in theory. Firstly, LMD method was introduced. Secondly, LMD method was compared with empirical mode decomposition (EMD) method and the results showed the superiority of LMD method. Finally, LMD method was applied to the pressure fluctuation signal of axial-flow pump and the PFs were extracted. Compared with EMD method, the results showed that LMD method can improve the time-frequency resolution and extract main vibration components accurately and effectively.