摘要
高频LLC谐振变换器具有效率高、电磁干扰(EMI)特性好、功率密度高等优点,但该变换器工作在欠谐振且轻载时,由于同步整流管有负电流的存在,会导致空载损耗较大和轻载效率低下。此处介绍了LLC变换器的基本工作原理,通过对一台功率为600 W的模块电源进行损耗分析计算,列出其轻载且工作在欠谐振状态下的损耗分布,最后针对几种不同的整流方法作出对比,提出一种使用同步整流管轻载移相的方法消除负电流和降低空载及轻载损耗。
High-frequency LLC converter have advantages of high efficiency,good electronic magentic interference(EMI) characteristics and high power density,etc.However,when working in under resonance and light load manner,such converters have large no-load power loss and low efficiency due to the existence of negative current of synchronous rectifier.The basic working principle of LLC converter is introduced,then the loss distribution of one kind of 600 W power module is illustrated through loss analyzing and calculating.Finally,based on comparative analyses of different rectification methods,a method by using light load phase shift for synchronous rectifier is proposed which can effectively eliminate negative current and reduce no-load and light load power loss.
作者
朱永亮
华明
ZHU Yong-liang;HUA Ming(Nanjing Research Institute of Electronics Technology,Nanjing 210039,China)
出处
《电力电子技术》
CSCD
北大核心
2020年第3期97-99,103,共4页
Power Electronics
关键词
变换器
同步整流管
轻载移相
converter
synchronous rectifier
light load phase shift
