Statistical modeling and signal reconstruction processing method of EMF for slurry flow measurement

• Published in: Measurement : journal of the International Measurement Confederation 2014-08, Vol.54, p.1-13
• Main Authors: Liang, Li-Ping, Xu, Ke-Jun, Wang, Xiao-Fen, Zhang, Zhen, Yang, Shuang-Long, Zhang, Ran
• Format: Article
• Language: English
• Subjects: DSP; Electromagnetic flowmeter; Probability density function model; Signal reconstruction; Slurry flow measurement; Statistical analysis
• ISSN: 0263-2241; 1873-412X
• DOI: 10.1016/j.measurement.2014.04.002

•An amplitude PDF model of EMF is built for slurry flow signal.•A signal reconstruction processing method is proposed.•High-low voltage switching mode based square-wave excitation.•A slurry-type electromagnetic flow transmitter is developed. According to the experimental data, an amplitude probability density function (PDF) model of the slurry flow signal is built up for electromagnetic flowmeter (EMF) by the method combining statistical analysis with numerical fitting, in order to reveal the effect of slurry noise on the flow signal and describe the features of slurry flow signal. Based on this model, a signal reconstruction processing algorithm is proposed to deal with the output signal of EMF sensor for realizing the slurry flow measurement. At the same time, the high-low voltage switching mode based square-wave excitation method is presented for EMF so as to reduce the slurry noise interferences. A slurry-type EMF transmitter is developed with a DSP chip – TMS320F28335, to implement the signal processing algorithm and control function. Finally water flow calibrations and slurry flow experiments are conducted to verify the reliability and stability of the method and system. Experimental results show that its measurement accuracy of water flow is better than 0.5%, and its steady-state volatility of paper slurry is less than 3%, and its dynamic response time is less than 4s.