Hydrogen consumption measuring system of fuel cell vehicle and use method thereof

The invention relates to a hydrogen consumption measuring system of a fuel cell automobile and a using method of the hydrogen consumption measuring system, and relates to the technical field of fuel cell automobiles. A hydrogen tank is arranged outside; the gas inlet end of the combined flow measurement module is communicated with the vehicle-mounted hydrogen tank and the external hydrogen tank through electromagnetic valves, and the combined flow measurement module is used for measuring the hydrogen inlet flow; the external nitrogen tank is communicated with the gas outlet end of the combined flow measurement module through an electromagnetic valve and is used for purging nitrogen to a pipeline corresponding to the gas outlet end of the combined flow measurement module; the waste discharge pipeline is communicated with pipelines corresponding to the air inlet end and the air outlet end of the combined flow measurement module; and the hydrogenation module is used for communicating with the gas outlet end of t