A method of selectively performing a purge of a fuel cell stack and fuel cell system

摘要

A method for selectively executing a purging of a fuel cell stack in a fuel cell system, the method comprising: it is determined on the basis of predetermined parameters whether a potential freezing state is present when a fuel cell system is shut down (14); Purifying reactant gas flow channels in the fuel cell stack when the potential freezing condition is present (18); shutting down the fuel cell system normally without reactant gas flow channel purging when the potential for a freezing condition is absent (22); periodically after the normal shutdown it is determined whether a potential freeze condition exists when the normal system shutdown is performed (24), and if the presence of a potential freeze condition is thereby determined, reactant gas flow passage purging is performed; characterized in that a warming strategy is initiated (28) prior to executing the reactant duct flushing if it is determined that a potential freezing condition exists after a system shutdown; that it is determined whether there is sufficient fuel and / or battery power to carry out the warming strategy; wherein the warming strategy is only initiated if there is sufficient fuel and / or battery energy to carry out the warming strategy, and if this is not the case, the purging is carried out.