High-Efficiency Resonant/Boost Converter Topologies Optimization for Light Electric Vehicle Charging: A Review
Keywords:
Bidirectional power flow, Boost converter, LEV charging, On-board charger, Resonant converter, Wide bandgap semiconductors, Zero voltage switchingAbstract
As light electric vehicle (LEV) charging infrastructure increasingly supports 400 V/800 V battery platforms, power-dense bidirectional converter architectures have become an important research subject. This paper provides a review of resonant and boost converter topologies for LEV on-board charging applications and a synthesis of peer-reviewed publications from 2024 to 2026 that examine efficiency, power density, wide voltage gain regulation, and bidirectional power flow. The review lays the theoretical groundwork of boost conversion and the LLC/CLLC resonant-tank behavior, and it synthesizes the literature into six cross-cutting themes. Wide-bandgap semiconductors combined with zero-voltage switching and resonant topologies consistently achieve efficiencies of 97% or higher, and integrating several discrete passive components yields significant power density benefits. For an extended voltage gain range with an unchanged semiconductor count, single-stage architectures face greater difficulty in meeting dynamic regulation requirements, and reconfigurable or morphing resonant-tank strategies have become the most widely accepted approach. The review also outlines persistent open issues, which are summarized as a prioritized research agenda: extended prototype scaling beyond laboratory power levels, analysis of 400 V/800 V platform compatibility, and consolidation of the parameters and equations required to define and analyze integrated magnetics.
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