Electrical and Thermal Co-simulation Tool for LLC Converter

Abstract

As one of the most popular isolated DC/DC converters, LLC resonant converter has found applications in many different industrial fields. Although traditional fundamental harmonic analysis (FHA) is widely adopted to analyze and design LLC resonant converter, high accuracy cannot be guaranteed, and considerable errors exist. Therefore, the driving force for this paper is to design an accurate LLC converter simulation tool, which including three aspects: 1) circuit model; 2) power loss model; 3) thermal model. These three aspects are closely related to each other. An accurate power loss model can only be obtained by using an accurate circuit model, and an accurate thermal model requires an accurate power loss model. Detailed discussions and comparisons for each model are presented in this paper. With the aid of the designed electrical and thermal simulation tool, analyzing and designing LLC resonant converter becomes convenient and time efficient. Meanwhile, education purpose of this paper is also of great importance, beginners could have a comprehensive understanding of an LLC resonant converter from circuit, power loss, and thermal perspectives.