AC/DC CONVERTER, AND COMPRESSOR DRIVING UNIT AND AIR CONDITIONER UTILIZING THE SAME

摘要

An AC-DC converter is provided which suppresses a harmonic current and improves power factor at low cost. Such an AC-DC converter includes a rectifier 2 connected to an AC power supply 1 via a reactor 5, capacitors 6, 7 connected in series across the output terminals of the rectifier 2, a first bidirectional switch 3 having one end connected to one input terminal of the rectifier 2 and the other end connected to a connecting point of capacitors 6, 7, a second bidirectional switch 4 having one end connected to the other input terminal of the rectifier 2 and the other end connected to the other end of the first bidirectional switch 3, and a control circuit 20 for actuating the first and second bidirectional switches 3, 4 during a half cycle of the AC power supply 1 so as to control a voltage inputted to the rectifier 2 to a desired output voltage.