Triple Active Bridge Topology Selection and Design for Integrated On-Board Chargers

This paper presents a detailed analysis of topology selection and design for a triple active bridge (TAB) converter tailored for integrated on-board charger (iOBC) applications in electric vehicles (EVs). The TAB converter is pivotal in seamlessly integrating high- and low-voltage batteries while ensuring galvanic isolation. Four distinct topologies are examined with respect to the input source at the secondary and tertiary ports: voltage-fed, current-fed, and a hybrid approach combining both. Comparative analysis identifies the superior performance of the all-voltage-fed topology, featuring a cascaded buck converter at the low-voltage terminal, which leads to the development and prototyping of a three-port transformer for this configuration. Experimental validation confirms its efficiency, demonstrating its suitability for iOBC implementations.