基于LLC谐振的新型软开关双向DC-DC变换器

Novel soft-switching bidirectional DC-DC converter based on LLC resonance

为了进一步提升户用储能系统中电池端双向DC-DC变换器的功率密度和效率,提出一种基于LLC谐振的新型软开关双向DC-DC变换器。该变换器有效降低了变压器匝比,提高了转化效率,在非对称半桥拓扑下可实现双向LLC特性,变换器中所有开关管均能实现软开关。同时该变换器结构简单,并可应用同步整流技术,具有效率高、成本低等优势。描述了所提变换器软开关的实现过程,进而分析了谐振特性和相关参数以及软开关的实现条件。最后制作了一台高压侧350~400 V、低压侧45~50 V的500 V·A实验样机,验证了所提变换器的有效性和实用性。

In order to further improve the power density and efficiency of the battery-side bidirectional DCDC converter in the household energy storage system,a novel soft-switching bidirectional DC-DC converter based on LLC resonance is proposed.The converter effectively reduces the transformer turns ratio and im?proves the conversion efficiency.The converter can realize the bidirectional LLC characteristic in the asym?metric half-bridge topology,and all the switches in the converter can realize soft switching.At the same time,the converter has a simple structure and can apply synchronous rectification technology,thereby having the advantages of high efficiency and low cost.The realization process of the soft switch of the converter is described,and then the resonance characteristics,the related parameters and the realization conditions of the soft switch are analyzed.Finally,a 500 V·A experimental prototype with a high voltage side of 350~400 V and a low voltage side of 45~50 V is fabricated,which verifies the effectiveness and practicability of the proposed converter.