In inverter control for supplying power to a motor, a power conversion device includes a temperature sensor for detecting a temperature of the inverter, a voltage sensor for detecting a voltage between terminals of a capacitor that smooths the voltage between terminals between the power source and the inverter, an inverter controller for controlling the inverter, a rotation speed sensor for detecting a rotation speed of the motor, an electric current sensor for detecting electric current supplied to the motor and a discharge determination instruction controller for giving an instruction for discharging electric charges accumulated in the capacitor, in which, control of reducing the rotation speed of the motor and discharge control of the capacitor are performed in accordance with the temperature of the inverter, the rotation speed of the motor and the electric current supplied to the motor.