A power conversion device includes a first inverter connected to first ends of windings of each phase of a motor, a second inverter connected to second ends of the windings of each phase, a first phase separation relay circuit to switch between connection and disconnection between the first ends of the windings of each phase and the first inverter, a second phase separation relay circuit to switch between connection and disconnection between the second ends of the windings of each phase and the second inverter, a sub-inverter circuit connectable to the first ends and the second ends of the windings of each phase, a third phase separation relay circuit to switch between connection and disconnection between the first ends of the windings of each phase and the sub-inverter circuit, and a fourth phase separation relay circuit to switch between connection and disconnection between the second ends of the windings of each phase and the sub-inverter circuit.