TWI810255B

The present invention provides an electric power converter with low loss, and the like. According to the present invention, a converter (100) is provided with a converter circuit (10) which converts an alternating current voltage into a direct current voltage, while being provided with: a reactor (L1) which is provided on a wiring line (p1) that connects an alternating current power supply (G) and the converter circuit (10) to each other; and a smoothing capacitor (C1) which smoothes direct current voltage applied from the converter circuit (10). The converter (100) is additionally provided with: reverse voltage application circuits (30a, 30b) which apply a reverse voltage to a free wheeling diode or parasitic diodes (Da, Db) of switching elements (Qa, Qb); and a control circuit (50) which makes a switch between driving and stopping of the reverse voltage application circuits (30a, 30b) in accordance with the magnitude of the load of the converter circuit (10).