In a power supply device, the bridge circuit including a plurality of switching arms which is an inverse-parallel circuit of a semiconductor switch and a diode. The power supply device includes a control unit. The control unit switches the semiconductor switch such that a voltage v between AC terminals becomes a positive-negative voltage whose peak value is the voltage Vo between the DC terminals only during prescribed time periods before and after a point that has deviated from each zero crossing point ZCP of a current i by a prescribed compensation period φ and such that the voltage v between the AC terminals becomes a zero voltage during the other time periods, and sets the compensation period φ such that a time period during which the voltage v between the AC terminals becomes a zero voltage is the shortest.