Patent ID: 6989211

Claim:
A method of operating a fuel cell, said fuel cell generating a fuel cell voltage and a fuel cell current and having a fuel cell temperature, said method comprising the steps of: selectively connecting and disconnecting the fuel cell to at least one electrical load dependent at least in part upon at least one of said fuel cell voltage, said fuel cell current and said fuel cell temperature, wherein said selectively connecting and disconnecting step comprises the steps of: determining that the fuel cell temperature is equal to or greater than an operating temperature; comparing the fuel cell voltage to an output voltage from a power switching device; biasing the power switching device into a linear mode of operation when the fuel cell temperature has reached the operating temperature and when the difference between the output voltage and the fuel cell voltage is less than 3.0 volts; and biasing the power switching device with a pulse-width modulated signal when the fuel cell temperature has reached the operating temperature and when the difference between the output voltage and the fuel cell voltage is at least 3.0 volts.