混合型LLC与DAB直流变换器及其滞环控制策略

摘要

This paper proposes a new breed of high-power DC/DC converter module based on hybrid LLC resonant and dual active bridge (DAB) converters.The voltage across the module could be clamped by LLC resonant converter based on its steady voltage characteristic,and let DAB take on the task of high power conversion.Such converter module can solve the problem that the power capability of LLC is limited by its resonant capacitor's current capability and simplify the control scheme of the whole module.Moreover,this paper designes a simple but effective hysteresis control scheme which could make the converter rapid stable response when the load is suddenly changed.Finally,an experimental prototype of hybrid high-frequency isolated DC/DC converter is designed and tested,the experimental result verify the effectiveness and correctness of the proposed topology and control scheme.%提出一种基于LLC谐振型变换器与双有源桥(DAB)直流变换器混合运行的大功率DC/DC模块.该模块利用LLC谐振变换器恒压调节的特性箝位模块两端电压,并利用DAB直流变换器的大功率能力承担大部分功率变换任务.在克服LLC型谐振变换装置功率变换能力受到谐振电容电流能力限制的同时,极大地简化了模块整体的控制策略复杂程度.同时,为该变换器模块设计了一种简单有效的闭环控制策略,该控制策略与所提出的结构相配合,能够保证在增减负荷时变换器模块能够快速恢复至稳定状态.最后,搭建了混合型高频隔离DC/DC变换器模块实验样机,验证了所提出结构和控制策略的有效性和正确性.