Hydrogenation machine with small-flow passages connected in parallel

The utility model discloses a hydrogenation machine with a small-flow passage connected in parallel. The hydrogenation machine comprises a small-flow filling pipeline connected to a main filling pipeline in parallel, the small-flow filling pipeline comprises a first control valve and a flow limiter, and the gas inlet end of the flow limiter is connected with the gas outlet end of the first control valve through a pipeline. The small-flow filling pipeline is connected to the main filling pipeline in parallel, so that when small-flow hydrogen filling needs to be carried out, the main filling pipeline is closed, the first control valve is opened, hydrogen can pass through the flow limiter of the small-flow filling pipeline, the flow of the hydrogen is limited by the flow limiter, and therefore the situation that hydrogen filling is completed too fast is avoided; the flow rate of hydrogen has enough time to be close to the linear relation with the opening degree of the flow limiter, so that the metering accuracy