Metering inaccuracy analysis and improvement measures of typical scenarios in hydrogen refueling station

Abstract

Standardizing hydrogen refueling station metering management promotes the economic and safe development of the hydrogen energy industry. In this study, by modifying the original equipment in hydrogen refueling stations, the real causes of hydrogen metering inaccuracy are experimentally investigated, and the effectiveness of the corresponding improvement measures is verified. While ensuring the accuracy of hydrogen metering, a segmented hydrogen loss rate calculation method has been proposed, which can assist in leak detection. The results show that the degree of variation in ambient temperature is the main factor affecting the metering accuracy of the PVT method, which is related to the difference in the rate of temperature rise within the hydrogen storage vessel and hydrogen piping. Differing from vehicle gas cylinders, the hydrogen tube bundle of the trailer does not produce a significant thermal equilibrium effect after filling, but the hydrogen metering errors are still not negligible because of sensitivity differences between pressure and temperature gauges and its large volume. Moreover, adding thermal insulation measures near the temperature gauge and improving the accuracy of the gauges can effectively reduce hydrogen metering errors.