Implementation of HF Current Injection Technique for Three-Phase AC-to-DC Converter

摘要

This paper presents the high power factor operation of three-phase AC-to-DC resonant converter. The input three-phase uncontrolled diode bridge rectifier is followed by six pulse modified series parallel resonant converter. The high power factor of three-phase AC source is achieved by injecting high frequency (HF) current from output of the inverter to the input of rectifier. Therefore, HF modulation of AC input voltage of the three-phase line rectifier circuit is achieved. The output voltage of three-phase resonant converter is regulated by using variable frequency mode under 180°-wide gating pulse scheme. Detail analysis and design of HF current injection circuit is given for 3.5 kW output power operating at 300 kHz switching frequency.