全桥LLC谐振变换器在轻载状态下的效率优化方法  

Efficiency Optimization Method of Full-bridge LLC Resonant Converter under Light Load Condition

作　　者：王科 彭晶 张旭鑫 杜宇维 WANG Ke;PENG Jing;ZHANG Xu-xin;DU Yu-wei(Electric Power Science Research Institute,Yunnan Power Grid Co.,Ltd.,Kunming 650214,China;Xi'an Microelectronics Technology Research Institute,Xi'an 710018,China;School of Electrical Engineering,Xi'an Jiaotong University,Xi'an 710049,China)

机构地区：[1]云南电网有限责任公司电力科学研究院,昆明650214 [2]西安微电子技术研究所,西安710018 [3]西安交通大学电气工程学院,西安710049

出　　处：《科学技术与工程》2025年第9期3704-3711,共8页Science Technology and Engineering

基　　金：中国南方电网有限责任公司创新项目(YNKJXM20222521)。

摘　　要：对于全桥LLC谐振变换器,在轻载时采用间歇控制(burst)策略是提升其轻载效率的一种有效手段。针对传统间歇控制对变换器的轻载状态效率提升效果有限和输出电压纹波大的问题,提出了一种改进型间歇控制方法。该控制方法固定了间歇导通时间,并使变换器在间歇导通时间内工作在谐振频率上,进一步提高了变换器的轻载效率,减小了输出电压纹波。为了验证所提方法的可行性,搭建仿真模型并对比分析了传统间歇控制策略与改进型间歇控制策略的仿真波形,并制作了一台额定功率100 W的实验样机,仿真及实验结果表明:全桥LLC谐振变换器采用改进型间歇控制策略时的输出电压纹波可以满足工程要求,并且相较传统的间歇控制策略,轻载时的效率最高有4.1%的提升。For full-bridge LLC resonant converter,intermittent control strategy is an effective means to improve its light load efficiency.An improved intermittent control method was proposed to solve the problems of limited efficiency improvement and large output voltage ripple in light load state of converter by traditional intermittent control.This control method fixes the intermittent conduction time and makes the converter work at the resonant frequency during the intermittent conduction time,which further improves the light load efficiency of the converter and reduces the output voltage ripple.In order to verify the feasibility of the proposed method,a simulation model was built and the simulation waveforms of the traditional intermittent control strategy and the improved intermittent control strategy were compared and analyzed,and an experimental prototype with rated power of 100 W was made.The simulation and experimental results show that the output voltage ripple of the full-bridge LLC resonant converter with the improved intermittent control strategy can meet the engineering requirements,and compared with the traditional intermittent control strategy,the efficiency under light load is improved by up to 4.1%.

关 键 词：LLC 轻载 效率优化 间歇控制 

分 类 号：TM461[电气工程—电器]