Power supply device for vehicle

A power supply device for a vehicle, comprising:

• an electric load that operates at a predetermined low voltage;
• a high-voltage power supply that provides a high-voltage DC power supply by connecting in series a plurality of power storage elements constituting nodes that supply said predetermined low voltage;
• a high-voltage load device connected to the high-voltage power supply via a wire harness;
• a plurality of switch means provided corresponding to said nodes that supply the predetermined low voltage to the electric load;
• a control means, wherein the control means supplies a voltage by turning on one of the switch means for supplying the voltage from at least one node and turning off the other switch means for supplying the voltage from the other nodes, and after setting a dead time period to turn off all the switch means once, by sequentially repeating turning on a next one of the switch means of a next node that supplies the voltage next and turning off the other switch means that supply the voltage from the other nodes so that the voltage is supplied from all the storage elements;
• a cutoff means for cutting off an electric circuit between the high-voltage power supply and the high-voltage load device;
• and
• a leakage detection means that detects a leakage current between the high-voltage power supply and a ground potential and sends a signal to said control means,
• wherein the control means determines the signal transmitted from the leakage detection means during the dead time period when the plurality of switching means are all off, and when the leakage current is equal to or higher than a predetermined current, the cutoff means are kept off for a predetermined period of time.