Fuel cell hydrogen supply system and control method

The invention relates to the technical field of fuel cells, and discloses a fuel cell hydrogen supply system and a control method. The system comprises a control module, at least two ejectors and a fuel cell stack, each ejector is provided with a first ejection inlet and a second ejection inlet, and the ejectors are used for outputting hydrogen introduced from the first ejection inlets and the second ejection inlets; an anode gas inlet of a fuel cell stack is correspondingly connected with an output end of an ejector, anode gas outlets of all the fuel cell stacks are communicated with one another, and the anode gas outlets of the fuel cell stacks output excessive hydrogen to all the second ejection inlets; and the control module regulates and controls the hydrogen mixing proportion of the anode gas inlet of the fuel cell stack according to the internal hydrogen humidity of the fuel cell stack. According to the invention, the plurality of fuel cell stacks are connected, so that the hydrogen circulates among th