A power conversion device includes: a plurality of 3-level converters (31 to 35) that are multiple-connected in series to an AC power supply; and a control device (10) controlling operations of the plurality of 3-level converters (31 to 35). The control device (10) includes: a calculation unit calculating an output voltage command for the plurality of 3-level converters (31 to 35); a carrier signal generation unit generating a carrier signal; a correction unit correcting a phase of the carrier signal based on a potential variation on a DC neutral point bus (7); and a pulse width modulation control. unit delaying the phase by a prescribed amount based on the carrier signal having the phase corrected by the correction unit as a reference phase, to generate a plurality of carrier signals, and comparing the output voltage command with each of the plurality of carrier signals to generate a control command for each of the plurality of 3-level converters (31 to 35).