Power supply apparatus and method for line connection type fuel cell system

A power supply apparatus for a line connection type fuel cell system, comprising:

• a fuel cell to generate a DC voltage;
• a converter to boost the DC voltage generated from the fuel cell;
• an inverter to convert the DC voltage from the converter into an AC voltage to apply the AC voltage to at least one load;
• a power converter system (PCS) control power supply which generates PCS control power from line power;
• a balance of plant (BOP) power supply which generates BOP power from line power;
• a regulator which generates PCS control power from the BOP power;
• a first switch coupled between the inverter and a power source, the first switch to direct the line power to one of the PCS control power supply or the BOP power supply;
• a second switch to switch an output of one of the PCS control power supply or the regulator to provide PCS control power;
• and
• a controller programmed to control switching of the first and second switches in response to a starting command,
• wherein, when the starting command is generated, the controller turns off the first switch and controls the second switch to couple an output terminal of the PCS control power supply to a PCS control board, and
• wherein, when the DC power is generated in the fuel cell, the controller turns on the first switch and controls the second switch to couple an output terminal of the regulator to a PCS control board.