Cost-Performance Pareto Analysis of DAB-based DC-DC Converter Topologies for LEV Chargers

This paper describes a systematic multi-objective design methodology for a 3.3 kW, 48 V Dual Active Bridge (DAB)-based converter suitable for the DC-DC stage of two-stage on-board chargers for light electric vehicles. Two different forms of the DAB topology, the voltage-fed (VFDAB) and current-fed DAB (CFDAB), in both non-interleaved and interleaved forms, are compared. A multi-objective optimization approach is adopted, which explores both hardware and software design variables’ space and considers average power loss over the charging cycle and total cost of switches (different types such as Si, SiC and GaN considered) as the figures of merit. Pareto-optimality analysis is used to identify the most suitable topology and some experimental results of a prototype of the same are presented.