**Preface to "Advances in High-Efficiency LLC Resonant Converters"**

LLC resonant converters have been widely used in industrial fields because of their high efficiency, simple structure, and cost-effectiveness. Many advanced technologies and approaches have been introduced and proposed to improve its power conversion efficiency, dynamic performance, stability, reliability, etc. using enhanced devices such as wide band-gap power switches and high-speed controllers. In addition, new and advanced control algorithms have been applied to the LLC resonant converters.

This book collects several research papers related to the LLC resonant converter, which were published in a Special Issue of *Energies* on the subject area of "Advances in High-Efficiency LLC Resonant converter". This Special Issue focused on emerging power electronic topologies related to the LLC resonant converter, and its design methodology and control algorithms. Topics of interest for publication include the following:


I believe that all the papers in this book will inspire further research topics and other researchers who are participating in the research of the LLC resonant converter. It was my pleasure to contribute to the Special Issue of *Energies* as a Guest Editor.

> **Jeehoon Jung** *Special Issue Editor*
