The invention relates to an
alternating current (AC) converter for converting
high voltage to
low voltage in the field of
power electronics. The converter comprises an AC
chopper circuit, a high-frequency
transformer circuit, a
rectifier and filter circuit, a waveform conversion circuit and a working frequency inversion circuit which are sequentially connected in series, wherein the AC
chopper circuit is used for converting input high-
voltage working frequency AC
voltage into high-frequency impulse high-
voltage AC voltage and outputting the converted voltage to the high-frequency
transformer circuit; the high-frequency
transformer circuit is used for converting high-frequency impulse high-voltage AC voltage into
full wave direct current (DC) voltage and outputting the
full wave DC voltageto the
rectifier and filter circuit; the
rectifier and filter circuit is used for converting the high-frequency impulse low-voltage AC voltage into
full wave DC voltage and outputting the full wave
DC voltage to the waveform conversion circuit; the waveform conversion circuit is used for boosting the full wave
DC voltage, adding input current to the full wave DC voltage and then outputting the combined voltage and current to the working frequency inversion circuit; and the working frequency inversion circuit is used for inverting the DC voltage into working frequency AC
sine wave voltage or AC
square wave voltage and outputting the inverted voltage. The converter is an AC-AC conversion circuit which has the advantages of small volume, light weight, high efficiency, low cost, simple designand high reliability and can run with a unit
power factor.