A bi-directional, isolated, single-stage, DAB-based AC-DC converter with open-loop power factor correction and other advanced features

Abstract

In this paper, a control method for an AC-DC converter is proposed that simultaneously has the following features: a) galvanic isolation b) bi-directional power flow, c) Zero Current Switching (ZCS) for the primary side switches and Zero Voltage Switching (ZVS) turn-on for the secondary side, d) linear power relationship for easy control implementation, e) unity power factor with open-loop control and f) single-stage power conversion. It is thoroughly analyzed by first assuming it to be a DC-DC converter in a push-pull topology and then extending the results to analyze an AC-DC converter. The conclusions of the analysis are confirmed by simulations.