摘要
提出一种具有自动均压和均流特性的组合式LLC谐振变换器。该变换器拓扑基于多个LLC模块的ISOP结构，通过在变换器前级开关电容网络中加入飞跨电容实现各串联模块输入端电压的均衡，在不同模块的谐振槽中串联耦合电感实现各模块电流的均衡。该拓扑保持了传统LLC谐振变换器的高效率、软开关和低电磁干扰（EMI）等优良特性，且具有控制简单、系统可靠性高等优点，非常适用于高降压比、大功率输出场合。以两个LLC模块的组合式变换器为例，对该拓扑的均压和均流原理进行详细分析。最后，通过一台输入400～550V、输出48V／24A的实验室样机，对该拓扑的均压和均流效果进行实验验证。
In this paper, a combined LLC resonant converter with voltage and current auto- balance capability is presented. Based on multi-phase LLC converter connected in input-series output-parallel （ISOP） structure, this converter can realize input voltage balance among modules by adding flying capacitor in switching-capacitor network, and reach current balance by adding coupled inductor in resonant tanks of LLC modules. The proposed topology has excellent performance of classical LLC converter in high efficiency, soft switching, and low EMI. Moreover, it is easily controllable and high reliable, which is suitable for high step-down conversion and high power output applications. Taken the topology with two modules as an example, the operation principle of the proposed topology is analyzed in detail. Finally, a prototype converter with 400~550V input and 48V/24A output has been built and tested, to verify the effectiveness of the proposed voltage and current auto-balance capability.
出处
《电工技术学报》
EI
CSCD
北大核心
2016年第20期151-160,共10页
Transactions of China Electrotechnical Society
关键词
LLC谐振变换器
输入串联输出并联
自动均压均流
飞跨电容
耦合电感
LLC resonant converter, input-series output-parallel, voltage and current auto-balance, flying capacitor, coupled inductor
