Fuel cell system and control method

According to the fuel cell system and the control method, the first diode module and the relay module are additionally arranged in the fuel cell system compared with an existing fuel cell system, the relay module is controlled to be in the closed state or the open state, and an electric loop of the fuel cell system can be controlled; when the relay module is in a closed state, the power battery supplies power to the air compressor module, enables the air compressor module to be in a working state and provides air for the fuel cell system, so that the fuel cell stack is in a working state, and at the moment, the relay module is controlled to be in a disconnected state; compared with an existing fuel cell stack which supplies power to the air compressor module through a DC/DC converter, the fuel cell stack in the fuel cell system supplies power to the air compressor module directly through the first diode module, the fuel cell stack is directly used for supplying power to the air compressor module, the power su