Abstract: A plurality of required DC voltages are outputted. A power supply device includes: a first switch circuit corresponding to the plurality of battery devices, and that includes a switch for connecting a negative pole terminal, by which negative pole terminals of the battery devices are connected, and a first switch for connecting a positive pole terminal, by which positive pole terminals of the battery devices are connected, and a switch for bypassing, by which the battery devices are bypassed; and a second switch circuit corresponding to the plurality of battery devices, and that includes a second switch for connecting a positive pole terminal, by which positive pole terminals of the battery devices are connected, and a switch for connecting, by which the negative pole terminals of the battery devices are connected to a positive pole terminal of the other battery device.

Abstract: A plurality of required DC voltages are outputted. A power supply device includes: a first switch circuit corresponding to the plurality of battery devices, and that includes a switch for connecting a negative pole terminal, by which negative pole terminals of the battery devices are connected, and a first switch for connecting a positive pole terminal, by which positive pole terminals of the battery devices are connected, and a switch for bypassing, by which the battery devices are bypassed; and a second switch circuit corresponding to the plurality of battery devices, and that includes a second switch for connecting a positive pole terminal, by which positive pole terminals of the battery devices are connected, and a switch for connecting, by which the negative pole terminals of the battery devices are connected to a positive pole terminal of the other battery device.

Abstract: A first switching circuit is connected between a transformer first winding and a DC power supply. A second switching circuit is connected between the transformer second winding and a battery. When charging the battery, a control circuit turns off an element in a second bridge circuit in the second switching circuit, and controls a phase shift amount of a first diagonal element, and a phase shift amount of a second diagonal element in the second bridge circuit, relative to a drive phase of a first reference element in a first bridge circuit in the first switching circuit. When discharging the battery, the control circuit turns off an element in the first bridge circuit and controls a phase shift amount of the second diagonal element and a phase shift amount of the first diagonal element relative to a drive phase of a second reference element in the second bridge circuit.

Abstract: A first switching circuit is connected between a transformer first winding and a DC power supply. A second switching circuit is connected between the transformer second winding and a battery. When charging the battery, a control circuit turns off an element in a second bridge circuit in the second switching circuit, and controls a phase shift amount of a first diagonal element, and a phase shift amount of a second diagonal element in the second bridge circuit, relative to a drive phase of a first reference element in a first bridge circuit in the first switching circuit. When discharging the battery, the control circuit turns off an element in the first bridge circuit and controls a phase shift amount of the second diagonal element and a phase shift amount of the first diagonal element relative to a drive phase of a second reference element in the second bridge circuit.