Patent ID: 8258740

Claim:
A method of starting operation of a fuel cell system, the method comprising the steps of: providing a fuel cell system comprising: a fuel cell for performing power generation by electrochemical reactions of reactant gases supplied to the fuel cell; an energy storage capable of storing and discharging electrical energy generated by power generation of the fuel cell, and capable of being directly coupled to the fuel cell; a DC-DC converter connected to the fuel cell and the energy storage; a load connected to the DC-DC converter, and operated by consuming at least electrical energy generated by the fuel cell or electrical energy discharged from the energy storage; and a fuel cell warming up control unit for warming up the fuel cell, during power generation of the fuel cell; determining whether the fuel cell is directly coupled to the energy storage at the time of warming up the fuel cell by the fuel cell warming up control unit; and if it is determined that the fuel cell is directly coupled to the energy storage, implementing voltage control to control an output voltage of the fuel cell applied to the load to become equal to, or higher than the terminal voltage of the energy storage.