A Comparative Analysis of DC–DC Resonant Converter Configurations, Modeling Methods, and Modulation Control Strategies for Battery Chargers

As electric vehicles (EVs) continue to gain widespread adoption, the need for highly efficientcharging infrastructure capable of enabling faster charging has become increasingly important.Modern EVs are equipped with larger battery capacities and extended driving ranges, whichrequire advanced fast DC charging solutions to meet their rapid charging needs. Resonant DC–DC converters are extensively utilized in electric vehicle (EV) applications because of theirsuperior efficiency, ability to achieve soft switching, and reduced electromagnetic interference(EMI). Among these, LLC and CLLC topologies offer high power density and reliableperformance over a wide operating range. This article reviews resonant converterconfigurations, modeling techniques, and control strategies, and addresses the challengesassociated with nonlinear resonant tank behavior. Various converter configurations wereanalzsed with respect to their efficiency, scalability, and regulation complexity. This alsohighlights that the unidirectional LLC resonant converter provides an optimal balance betweensimplicity, cost, and performance for EV charging applications.