定频PWM控制混合桥双LLC谐振变换器研究  

Research on Hybrid Bridge Dual-LLC Resonant Converter under Fixed-frequency PWM Control

作　　者：潘健[1] 宋豪杰 刘松林 熊嘉鑫 PAN Jian;Member;CPSS;SONG Haojie;LIU Songlin;XIONG Jiaxin(School of Electrical and Electronic Engineering,Hubei University of Technology,Wuhan 430068,China)

机构地区：[1]湖北工业大学电气与电子工程学院,武汉430068

出　　处：《电源学报》2024年第5期120-132,共13页Journal of Power Supply

基　　金：太阳能高效利用及储能运行控制湖北省重点实验室开放基金资助项目(HBSEES201902)。

摘　　要：针对宽输出电压应用中传统频率控制LLC谐振变换器工作频率范围宽且存在较大循环电流的问题,提出1种定频PWM控制混合桥双LLC谐振变换器。根据原边侧结构的不同,所提变换器有3种拓扑结构形式,分别为半桥-半桥双LLC谐振变换器、半桥-全桥双LLC谐振变换器、全桥-全桥双LLC谐振变换器。其中,原边侧结构并联输入,2个变压器二次侧串联输出。相较于传统频率控制LLC变换器,3种拓扑形态始终在谐振频率点工作,缩小了开关频率范围;在PWM控制策略下,可以分别实现2倍电压增益、3倍电压增益和4倍电压增益以适应宽电压场合;电路中循环电流损耗低,软开关性能良好。Simulink仿真和实验结果验证了所提方案的可行性。Aimed at the problem of wide frequency range and large circulating current with the traditional frequency-controlled LLC resonant converter in wide output voltage applications,a fixed-frequency PWM controlled hybrid bridge dual-LLC resonant converter is studied.According to the difference in the primary-side structure,the converter has three forms of topology,i.e.,half-bridge-half-bridge,half-bridge-full-bridge and full-bridge-full-bridge,in which the primary-side structure is in parallel and the two transformers on the secondary-side are in series.Compared with the traditional frequency-controlled LLC converter,the three topologies always work at the resonant frequency,which reduces the switching frequency range.In addition,under the PWM control strategy,the three topologies can achieve 2,3 and 4 times voltage gain,respectively,thereby adapting to wide voltage scenarios.At the same time,the circuit has a low circulating current loss and a good soft switching performance.Simulink simulation and experimental results verified the feasibility of the proposed scheme.

关 键 词：定频PWM控制 谐振变换器 宽输出电压 软开关 

分 类 号：TM46[电气工程—电器]