Passive shaping of line current waveform by converter with alternating of parallel and series resonance in AC-DC switch mode power supplies

摘要

The distortion of an AC-DC converter current could be corrected by use of a fast-controlled impedance-matching transformer on a basis of a non-conducting converter with alternating of parallel and series resonance. The basics of the converter performance and operation are described. Changes in the converter input impedance can be eliminated by means of the varying transformation ratio. It is found that the current waveform can be made sinusoidal if the instant power passing through the converter is proportional to the squared instant value of the mains voltage and/or the output voltage and current of the converter are in inverse proportion.