A power conversion device includes a carrier generating unit, a setting unit, a PWM signal generating unit, and a power conversion unit. The carrier generating unit generates a carrier of a particular set carrier frequency during a certain continuation time. The setting unit sets the continuation time to be random and sets one carrier frequency among a plurality of mutually-different carrier frequencies as the set carrier frequency. The PWM signal generating unit generates a PWM signal based on the carrier generated by the carrier generating unit. The power conversion unit executes a power conversion based on the PWM signal and supplies converted power to a load.
