Achieving Unity Power Factor with a Unidirectional Single-Phase Four Reverse Blocking IGBTs Buck Type Rectifier

Abstract:
This work aims to study a single phase Buck-Boost charger for electric vehicles. Buck-type rectifiers inject low order input current harmonics into AC mains. Thus, an inductor-capacitor (LC) based input filter is employed. The capacitor’s reactive energy results in a leading grid current. In order to achieve a unity displacement power factor, a phase shift based control is implemented. This control strategy combined with the topology of the Buck converter results in a periodical resonance of the input filter. An active damping with resonance frequency tracking that achieves a good power factor while meeting the IEC’s International Standards on harmonic current emissions is, thus, proposed and studied.