Analysis & Simulation of Different LLC Converter Topologies

Abstract

There is an expanding trend in electric vehicle (EV) technologies because of finite fuel sourcesand environmental concerns. One of the essential barriers in EVs commercialization is the charging ofbatteries. The inductor-inductor-capacitor (LLC) resonant converter appears the most appealing design dueto its advantages, such as small electromagnetic interference, obtaining high-power density, ability to bedesigned at very high switching frequencies, operation for wide input and output voltage range with narrowswitching frequency variation, and high efficiency. This study compares different topologies of LLCresonant converter that can be adapted as battery charger of electric vehicle. The schematics of topologies,detailed design calculation of the parameters, simulation results of topologies to show the circuitperformance are presented, respectively. The simulation model is realized for whole examined topologieswith a proportional integral controller to obtain constant output voltage using MATLAB. LLC resonantcircuit is designed for the input voltage range of 305-345V, output voltage range of 36-58V, and outputpower of 700W. Analytical and simulation results are included in this study to illustrate the performancedifferences among the presented topologies of LLC resonant converter in terms of structure, efficiency, anddynamic response at sudden load changes.