The Anti-strong Vibration Method Based on Noise Template and Cross Correlation Calculation for Vortex Flowmeter
XU Ke-Jun1,2,WANG Qin1,FANG Min1,SHAO Chun-li1
1.School of Electrical and Automation Engineering, Hefei University of Technology, Hefei, Anhui 230009, China;
2.Engineering Technology Research Center of Industrial Automation, Anhui Province, Hefei, Anhui 230009, China
Abstract:A vibration experimental set-up of the vortex flowmeter is built and the vibration experiments are performed according to practical conditions of vortex flowmeter subjected to the strong vibration noise in industrial fields. The experimental data are analyzed by the power spectrum to obtain the features of frequency bandwidth. The noise templates are built up, and the frequency bandwidth characteristics of noise are described quantitatively. Cross correlation between the noise template and the power spectrum of vortex sensor output signal is calculated. A new kind of method is proposed by using the normalized cross correlation coefficient curves of the noise and vortex signal so as to distinguish the vortex signal from the strong vibration noise. The experimental data collected in the vibration experiments are processed with this algorithm to verify its effectiveness.
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