Patent ID: 8389136

Claim:
A gas flow control assembly for use in a fuel cell system, comprising: an airflow control assembly which adjusts flow rate of air to a cathode side of said fuel cell system based on variations in amount of unreacted fuel in an anode exhaust gas leaving an anode side of said fuel cell system; and a fuel flow control assembly including a controller programmed to control flow rate of fuel to said anode side of said fuel cell system based directly on adjustment to said air flow rate by said airflow control assembly, wherein the fuel cell system includes an oxidizing assembly for preheating the air to a predetermined temperature using anode exhaust gas containing unreacted fuel; and the airflow control assembly adjusts the air flow rate based on variations in temperature from the predetermined temperature of the preheated air resulting from changes in the amount of unreacted fuel in the anode exhaust gas so as to maintain the temperature of the preheated air at the predetermined temperature.