Abstract: A power conversion device that can be shared by batteries having different output voltages is disclosed. This power conversion device converts an output voltage of a battery into an AC voltage or a DC voltage lower in voltage than the output voltage of the battery, and includes a multi-winding transformer (1), and a first DC/AC converter (11) and a second DC/AC converter (12) whose DC sides are connected to the battery. In a case where the output voltage of the battery is larger than a withstand voltage of semiconductor switching elements, respective DC inputs of the first DC/AC converter (11) and the second DC/AC converter (12) are connected in series to each other.

Abstract: Provided is an integrated power supply device in which AC sides of three or more DC/AC circuits are coupled by a transformer having three or more windings. The integrated power supply device is capable of correctly outputting power in all assumed driving modes (power directions) and reducing a loss without adding a discharge device. In the integrated power supply device in which AC sides of three or more DC/AC circuits are coupled by a transformer having three or more windings, the three or more DC/AC circuits include a first DC/AC circuit that includes a first switching circuit and a capacitor connected in parallel to the first switching circuit and a second DC/AC circuit that includes a second switching circuit connected to a power storage unit.