Resonant Power Converters: An Overview with Multiple Elements in the Resonant Tank Network

Finite commutation times are associated with the concurrent occurrence of both voltage-across and current-through semiconductor switches, leading to switching power losses. To alleviate them, soft-switching techniques have been developed. Soft-switching converters can be classified into quasi-resonant and multiresonant, resonant-transition, and resonant power converters (RPCs). This article focuses on RPCs, due to their high power density and efficiency. Specifically, RPC topologies with multiple elements are described, and their input-output relationships and efficiency are illustrated. The merits and limitations of RPCs are discussed and compared. An RPC intended to charge the battery of an electric vehicle (EV) is presented, and experimental results are discussed.