Convertor device and air conditioner

A convertor device (2) has two switching circuits (10a, 10b) provided in parallel with each other between a rectifier circuit (5) and a smoothing capacitor (12). A convertor control unit (15) generates a first switching signal for one switching circuit by comparing a reference waveform for a prescribed carrier frequency with a voltage command, and generates a second switching signal for the other switching circuit by comparing the voltage command with a phase-inverted reference waveform having the phase of the reference waveform shifted by 180 DEG. A DC voltage is boosted and an AC input current harmonic is reduced by controlling the opening and closing of switching elements (8a, 8b) of switching circuits (10a, 10b) on the basis of the first switching signal and the second switching signal, and thereby achieves a reduction in size and simplification of the device.