Power source control unit of electric supercharger

A power source control apparatus comprising:

• an inverter which drives an electric motor of an electric supercharger and detects the operating power of said electric supercharger;
• and
• a power supply control unit which controls a power supply to said electric supercharger via said inverter and a power supply to an on-vehicle electrical equipment other than said electric supercharger, and includes:
• a generator which generates electric power using a power of an internal combustion engine,
• a first battery which supplies electric power to said on-vehicle electrical equipment,
• a voltage detector which detects a voltage of said first battery,
• a second battery which supplies electric power to said inverter,
• a switch which switches between said first battery and said second battery,
• a current amount detector which detects an amount of current carried through said switch, and
• a controller which controls said switch in accordance with the voltage of said first battery that said voltage detector detects, the operating power of said electric supercharger that said inverter detects, and the amount of the electric current carried through said switch.