Fuel cell system

A fuel cell system, comprising:

• a fuel tank for storing fuel;
• evaporating means for evaporating said fuel to generate fuel gas;
• reforming means for generating reformed gas containing hydrogen from said fuel gas;
• combusting means for burning one of said fuel in said fuel tank and said reformed gas to supply heat to said evaporating means;
• a fuel cell for generating electricity by use of said hydrogen contained in said reformed gas generated in said reforming means;
• boiling point temperature estimating means for estimating a boiling point temperature of said fuel in said evaporating means based on an operation pressure of said evaporating means;
• vapor temperature measuring means for measuring a vapor temperature of fuel gas in said evaporating means;
• and
• flow rate control means for increasing a flow rate of one of the fuel and the reformed gas burnt in said combusting means when a value obtained by subtracting said boiling point temperature from said vapor temperature becomes below a predetermined value.

A method of controlling a fuel cell system including a fuel tank for storing fuel;

• an evaporator for evaporating said fuel to generate fuel gas;
• a reforming reactor for generating reformed gas containing hydrogen from said fuel gas;
• a combustor for burning one of said fuel in said fuel tank and said reformed gas to supply heat to said evaporator;
• a fuel cell for generating electricity by use of said hydrogen contained in said reformed gas generated by said reforming reactor, said method comprising:
• estimating a boiling point temperature of said fuel in said evaporator based on an operation pressure of said evaporator;
• measuring a vapor temperature of the fuel gas in said evaporator;
• and
• increasing a flow rate of one of the fuel in said fuel tank and the reformed gas burnt in said combustor when a value obtained by subtracting said boiling point temperature from said vapor temperature becomes below a predetermined value.