System and method for fuel cell

A fuel cell system comprising:

• an ejector provided in a hydrogen supply line;
• a hydrogen pressure sensor provided in the hydrogen supply line at a front end portion of the ejector and configured to measure a pressure of hydrogen flowing in from a hydrogen tank connected to the hydrogen supply line;
• a supply valve provided in the hydrogen supply line at a front end portion of the hydrogen pressure sensor and configured to control a flow rate of the hydrogen supplied from the hydrogen tank to an anode of a fuel cell stack of the fuel cell system;
• a discharge valve provided in a hydrogen discharge line fluidically connected to the anode;
• and
• a controller electrically connected to the supply valve and the discharge valve and configured to distinctly estimate the pressure of the hydrogen flowing into the anode of the fuel cell stack from a rear end portion of the ejector for each open or closed state of each of the supply and discharge valves, and to control the supply and discharge valves based on a pressure estimate value of the hydrogen,
• wherein the controller is configured to determine a target supply pressure of the hydrogen and a target discharge flow rate of the hydrogen based on the pressure estimate value of the hydrogen, to control the supply valve based on the target supply pressure of the hydrogen, and to control the discharge valve based on the target discharge flow rate of the hydrogen.