A Three-Port DC-DC-DC Converter based on Dual Active Bridge Series Resonant Topology for Electric Vehicle DC Fast Charging Applications

This paper proposes a three-port dc-dc-dc converter based on dual active bridge series resonant (DABSR) and interleaved boost topology that integrates PV, electric vehicle (EV) battery, and dc-link situated between ac-dc stage and dc-dc stage of the EV dc fast charger. The power flow between port-1 (dc-link) and port-3 (EV battery) occurs due to the phase shift between input and output bridge switching of DABSR topology. We adopt triple phase shift (TPS) modulation that secures zero voltage switching (ZVS) of all the switches for a wide range of EV battery voltage and hence, overall efficiency is increased. The circuit works as an interleaved boost converter between port-1 (dc-link) and port-2 (PV) while interrupting the power flow between port-1 and port-3 with the proper selection of phase shift and duty cycles. The dc-link voltage remains constant during port-2 to port-3 power transport which also utilizes DABSR topology. Operating principles of different power flow modes have been discussed and simulation performed in Matlab/Simulink validates the feasibility of the proposed converter as the dc-dc power stage of the EV dc fast charger.