Improvements of Anti-strong-vibration Method Combing Digital Filter with Auto-correlation 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:Vortex flowmeter is susceptible to the interference of pipe vibration, which affects on the measurement accuracy greatly. Adopting normal digital signal processing methods cannot obtain the accurate vortex frequencies when the power of vibration noise is larger than that of the vortex signal. Therefore a digital signal processing technique combining digital filter with autocorrelation was proposed to apply the signal processing of vortex flow sensor for extracting the flow rate information from the signal containing strong vibration interference. Aiming at the implementing problems of this method in practice application, the existing system software is improved. The autocorrelation function is calculated by using real number FFT algorithm with assemble language based on MSP430F5418 MGU in order to speed up computation.
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