机电工程技术2025，Vol.54Issue(3)：138-147,169,11.DOI:10.3969/j.issn.1009-9492.2025.03.025
针对LLC谐振变换器宽范围高效率输出的研究与设计
Research and Design of Wide-range and High-efficiency Output For LLC Resonant Converter
摘要
Abstract
Traditional LLC resonant converters can only achieve soft switching when the operating frequency is near the resonant frequency point,and the adjustment of output voltage needs to be achieved by adjusting the operating frequency.Once the output voltage range is wide,it will cause the LLC resonant converter to lose its soft switching characteristics.Therefore,the soft switching characteristics and the wide range of output voltage often cannot be achieved simultaneously.An LLC BUCK converter is proposed,which adopts a parallel input and series output method of LLC circuit and BUCK circuit,and the LLC circuit adopts open-loop control with resonant frequency as the operating frequency.The BUCK circuit adopts PI closed-loop control.This method combines the strong load capacity of LLC circuits with the wide voltage regulation ability of BUCK circuits.Simulation platform is built in MATLAB for simulation experiments and compares it with traditional LLC resonant converters.A prototype with 60 V input voltage,12～36 V adjustable output voltage and a maximum output power of 500 W is made,tests are carried out on the prototype.Simulation results show that,the LLC-BUCK converter has a voltage output range that is twice of the traditional LLC resonant converter,and its operating efficiency is higher than that of the traditional LLC resonant converter under the same output voltage.Test results obtained from the prototype are basically consistent with the simulation.The working efficiency test of the prototype turns out that,the highest efficiency value is 96.7%at output voltage being 12 V.The lowest efficiency value is 88.3%at output voltage being 36 V.Simulation and prototype tests verifies that the LLC-BUCK converter proposed can achieve wide range voltage output and high efficiency.关键词
LLC谐振变换器/LLC-BUCK变换器/软开关/高效率/宽电压输出/PI控制Key words
LLC resonant converter/LLC BUCK converter/soft switching/high efficiency/wide voltage output/PI control分类
信息技术与安全科学引用本文复制引用
肖康,陈威,许海波,林振权,孙永乐..针对LLC谐振变换器宽范围高效率输出的研究与设计[J].机电工程技术,2025,54(3):138-147,169,11.基金项目
温州市重大科技创新攻关项目(ZG2022002,ZG2023032) （ZG2022002,ZG2023032）
