寄生电容对LLC谐振变换器的影响分析  

Analysis of Impact of Stray Capacitance on LLC Resonant Converter

作　　者：俞珊[1] 徐志望 董纪清[3] YU Shan;XU Zhiwang;DONG Jiqing(Zhicheng College,Fuzhou University,Fuzhou 350002,China;Fujian Raynen Technology Co.,Ltd,Fuzhou 350003,China;College of Electrical Engineering and Automation,Fuzhou University,Fuzhou 350116,China)

机构地区：[1]福州大学至诚学院,福州350002 [2]福建睿能科技股份有限公司,福州350003 [3]福州大学电气工程与自动化学院,福州350116

出　　处：《电源学报》2018年第2期124-130,共7页Journal of Power Supply

基　　金：福建省教育厅科技基金资助项目(JA14356;JA15622);福建省自然科学基金资助项目(2014J01178)~~

摘　　要：在进行LLC变换器的设计过程中,极易忽略寄生电容对变换器的影响。从寄生电容的产生机理出发,分析了寄生电容对LLC变换器工作原理特性的影响。寄生电容的存在不仅影响原边开关管的软开关过程,而且会使输出电压增益在轻载或空载下出现失真现象。在优化死区时间的基础上,综合比较已知增益失真解决方案,提出一种新颖的双滞环自适应Burst数字控制方案,在稳定变换器输出电压的同时,提升轻载下的变换效率。最后,通过样机实验验证了所提控制方案的正确性与合理性。It is easy to ignore the impact of stray capacitance on the converter during the design process of an LLC converter.In this paper,the impact of stray capacitance on the working principle of LLC converter is analyzed on the basis of the developing mechanism of stray capacitance.The existence of stray capacitance not only affects the softswitch process of primary switch,but also distorts the output voltage gain under light or no load.Based on the optimization of dead time and compared with the existing solutions to the problem of gain distortion,a novel dual hysteresis adaptive Burst digital control scheme is proposed to improve the conversion efficiency under light load while stabilizing the converter output voltage.Finally,the correctness and feasibility of the proposed control scheme were verified by tests on an experimental prototype.

关 键 词：寄生电容 LLC变换器 软开关 增益失真 

分 类 号：TM470[电气工程—电器]