A power converter control device includes an alarm signal generation circuit which detects information necessary for a protection operation of a semiconductor element configuring a power converter, and generates and externally outputs an alarm signal with a pulse width responding to a protection factor; a temperature signal generation circuit which detects a temperature of the semiconductor element, and generates a PWM signal, correlated with the temperature, the cycle of which is different from the pulse width of the alarm signal; and an output control circuit which selects the PWM signal in normal time, and selects and externally outputs the alarm signal in place of the PWM signal when the alarm signal is generated.