Power supply apparatus for vehicle

A power supply apparatus for a vehicle which supplies electric power to a power supply unit and charges electric power from the power supply unit to a battery of the vehicle via a power port, wherein

• the vehicle includes a first power inverter circuit which supplies electric power to a load and receives electric power from the load, a capacitor which is connected to the first power inverter circuit, a high-resistance electric path and a low-resistance electric path which electrically connect between the capacitor and the battery and whose resistance values are different from each other, a first switching unit which opens/closes the high-resistance electric path and the low-resistance electric path, and a unit which operates the first switching, unit, when connecting between the battery and the first power inverter circuit, in such a manner that after a first state is maintained in which the high-resistance electric path is closed and the low-resistance electric path is opened, a second state is maintained in which the high-resistance electric path is opened and the low-resistance electric path is closed, comprising:
• an electric power transferring electric path arranged to connect the power port to the first power inverter circuit;
• an operating unit configured to operate the first power inverter circuit to supply electric power to the power supply unit and receive electric power from the power supply unit;
• a prohibiting unit configured to prohibit the electric path between the power supply unit and the first power inverter circuit from closing in response to the amount of charge of the capacitor being equal to or less than a predetermined value;
• and
• a unit configured to measure voltage across the capacitor,
• the prohibiting unit being configured to determine that the amount of charge is equal to or less than the predetermined value in response to the measured voltage being equal to or less than a threshold value.