Comparative Analysis of Resonant Converters for EV Charging Applications

The wide applications of Electric Vehicles (EVs) for integration with renewable energy sources need high-power, isolated bidirectional converters (IBC). Bi-directional converters often suffer from high switching power losses leading to efficiency reduction. Therefore many topologies are proposed to achieve soft switching and increase the converter efficiency. Among the available topologies, resonant converters (RC), such as LLC, CLLC, CLLLC, and dual active bridge (DAB) converters, are widely employed for high-power conversion because of their superior efficiency and soft-switching capabilities. In this article, a comprehensive comparative performance analysis of different RC topologies is presented. Among these, the CLLLC converter topology has emerged as a promising solution, offering higher efficiency and an extended soft-switching range compared to other RCs. Performance validation of various RCs is obtained through an experimental prototype.