POWER CONVERSION APPARATUS

A power conversion apparatus () is used so as to be connected to three voltage units. The power conversion apparatus includes three power-conversion circuit units and a transformer (). The three power-conversion circuit units are respectively connected to voltage units that differ from one another. Three coils () of the transformer () are connected to power-conversion circuit units that differ from one another. The three coils () are magnetically coupled with one another. The three coils () are arranged so as to be arrayed in a coil axial direction (z). One of the voltage units is a high-voltage battery. Among the coils other than a high-voltage battery-side coil () that is connected to the high-voltage battery, the coil () of which a power value that flows thereto is largest is arranged in a position that is adjacent to the high-voltage battery-side coil ().