Fuel cell system and method of controlling the system

摘要

A fuel cell system is provided in which the concentration increase of discharged fuel gas is inhibited even when abnormality is detected in a discharge unit. A fuel cell system in which a fuel gas discharged from a discharge unit (SV5) is diluted with an oxidizing gas (14) and discharged comprises an abnormality detection unit (205) for detecting an operation abnormality of the discharge unit (SV5), and a change unit (206, 207) for changing the supplied quantity of the oxidizing gas when an abnormality of the discharge unit (SV5) is detected, and the concentration of the diluted (14) and discharged fuel gas is changed and inhibited by changing the supplied quantity of the oxidizing gas.

主权项

1. A fuel cell system comprising:
a fuel gas tank for supplying a fuel cell with fuel gas; a purge valve for purging fuel gas from a fuel gas electrode of the fuel cell; a diluting device for diluting the fuel gas discharged from the purge valve with an oxidizing gas, wherein the diluting device is connected to the purge valve, and the diluting device is configured to discharge the fuel gas discharged by the purge valve after dilution with the oxidizing gas; a pressure sensor that detects pressure of the fuel gas upstream of the purge valve, downstream of the purge valve or both upstream and downstream of the purge valve; and an electronic control unit with control logic, which is programmed to:
determine a required output quantity of the fuel cell;supply the oxidizing gas to the fuel cell in a supply quantity corresponding to the required output quantity;detect an operation abnormality of the purge valve in which the purge valve fails to open despite a valve opening command when the pressure of the fuel gas detected by the pressure sensor is different from that of expected pressure when the purge valve is operating normally; andchange the supplied quantity of said oxidizing gas when the operation abnormality of the purge valve is detected, wherein when the operation abnormality of the purge valve is detected, the electronic control unit is programmed to change a quantity of the oxidizing gas to be larger than the supplied quantity corresponding to the required output quantity and to supply the changed quantity of the oxidizing gas to the fuel cell.