Inverter control device

Provided is an inverter control device that can detect momentary abnormality in a power-supply voltage for sure, and return quickly to regular state when the abnormality in the power-supply voltage has been settled. The inverter control device consists of a main power-supply (31); a sub power-supply (22) that converts electric power distributed from the main-power supply (31); a controller (21) that operates with a control power-supply supplied from the sub power-supply (22); a transistor (4) that makes the input signal of the controller (21) turn ON/OFF, by having the current between the emitter and collector made to turn ON/OFF; and a power-supply monitoring circuit (3) that is connected to the main power-supply (31) via at least a resistor (r D ), and monitors the voltage of the main power-supply (31). The emitter terminal of the transistor (4) is connected to the ground, the base terminal of the transistor (4) is connected to the output terminal of the power-supply monitoring circuit (3) via a resistor (r