Abstract To meet the requirements of low power consumption of electromagnetic water meters, an intermittent excitation method was proposed, and three-value wave excitation was performed every cycle. In response to the requirements of electromagnetic water meters to achieve a very low measurement lower limit under the condition of a small excitation current and a very weak sensor output signal, a processing method of signal reconstruction filtering was proposed to reconstruct the amplitude demodulated signal into a rectangular wave signal, so as to facilitate the comb band-pass filtering of the signal, thereby ensuring the measurement accuracy of electromagnetic water meters. The transmitter based on the MSP430 low-power MCU was developed and the water flow calibration experiments were carried out. The results show that the system can meet the measurement accuracy of the first-class water meter, and the lower limit of flow measurement can reach 0.4m3/h, and the turn-down ratio can reach 400.
YU Xin-long,XU Ke-jun,XU Wei, et al. Development of Electromagnetic Water Meter Transmitter Based on Intermittent Excitation and Signal Reconstruction[J]. Acta Metrologica Sinica, 2021, 42(9): 1160-1166.
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2021, Vol. 42 
