智能膜式燃气表自动化校准技术

Automatic Calibration Technology of Intelligent Diaphragm Gas Meter

分析当前智能膜式燃气表及改进后的智能膜式燃气表原理,提出一种通过光学接口按照近红外通信协议的相对误差校准技术,通过改进结构,取消机械计数器,增加光学接口,通过脉冲当量实施初校、修正、复校,实现自动化校准。以准确度等级为0.5级、流量范围为0.016~6.000 m 3/h音速喷嘴气体流量标准装置,测试规格为G1.6、流量范围为0.016~2.500 m 3/h的1.5级燃气表,比较近红外通信方法测试与静态法测试的相对误差差异,结果表明相对误差差异在0.13%以内,小于标准装置扩展不确定度(0.5%)。近红外通信方法测试的准确性满足要求,复校效率提升了约73%。

The principles of the current intelligent diaphragm gas meter and the improved intelligent diaphragm gas meter are analyzed.A relative error calibration technology according to the near-infrared communication protocol through the optical interface is proposed.By improving the structure,canceling the mechanical counter and adding the optical interface,the preliminary calibration,correction and recalibration are implemented through pulse equivalent to realize the automatic calibration.The sonic nozzle gas flow standard device with an accuracy grade of 0.5 and a flow range of 0.016 to 6.000 m 3/h is used to test the 1.5 level gas meter with G1.6 specification and flow range of 0.016 to 2.500 m 3/h.The relative error difference between near-infrared communication method and static method is compared.The results show that the relative error difference is within 0.13%,which is less than the standard device's expanded uncertainty(0.5%).The accuracy of near-infrared communication method meets the requirements,and the recalibration efficiency is increased by about 73%.