A power inverter control device is designed to control a neutral point clamped power inverter apparatus including first to fourth self-extinction elements sequentially connected in series between two end terminals of a power supply having an intermediate terminal, four freewheeling diodes connected in parallel with the self-extinction elements in a direction opposite thereto, a series circuit of first and second clamping diodes, connected in parallel with a series circuit of the second and third self-extinction elements in a direction opposite thereto and having a node connected to the intermediate terminal of the power supply. The control device includes a circuit for generating a first PWM control signal having a pulse width corresponding to a load current, and a PWM control circuit for converting the first PWM control signal into a second PWM control signal having a pulse width equivalent to the sum of the pulse width of the first PWM control signal and a width corresponding to one of turn-on and turn-off periods of each of the self-extinction element, and supplying the second PWM control signal to the first to fourth self-extinction elements.