Wide Operating Range Single-Stage Bidirectional Impedance Control Network-based Onboard Electric Vehicle Charger

This paper introduces a high-performance single-stage bidirectional impedance control network (ICN)-based ac-dc converter for onboard electric vehicle charging application. ICN-based converters operate at a constant switching frequency and comprise a differential resonant network which provides differential phase shift to maintain soft-switching over a broad range of operating conditions. The proposed bidirectional ac-dc converter has full soft-switching capability for wide input and output voltage, and power ranges. A generalized phase shift control methodology which enables soft switching, power factor correction (PFC), and output power regulation in both forward and reverse operational modes is proposed. An auxiliary zero voltage switching (ZVS) inductor-based approach is also presented to achieve soft-switching of all transistors without affecting the PFC and soft switching properties of the conventional design. A universal input (90 -305) wide output voltage (200 V-500 V), 1.7-kW onboard electric vehicle charger is designed, built, and tested to experimentally validate the proposed control and design methodologies. The prototype achieves soft switching of all high frequency transistors and achieves a peak efficiency of 93.5% at 1.7kW.