1. School of Electrical and Automation Engineering, Hefei University of Technology, Hefei, Anhui 230009, China
2. Engineering Technology Research Center of Industrial Automation, Hefei, Anhui 230009, China
Abstract:From the perspective of measurement principle, the influence of ambient temperature change on three kinds of transient electromagnetic flow measurement methods is analyzed. It is found that the voltage-current ratio and voltage-current differential method are greatly affected by the change of ambient temperature, while the differential interference compensation method itself has a good ability to suppress ambient temperature change. In view of the fact that the differential interference compensation method may cause errors to increase in the process of practicality, the optimal calculation method of differential interference coefficient and the optimal selection of excitation frequency are given. It is confirmed by the water flow calibration experiment that the differential interference compensation method has a better compensation effect on the ambient temperature changes when the variation of the ambient temperature does not exceed ±20℃, and the flow measurement results can meet the accuracy requirements of 0.5 level.
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