输入输出共地型三电平Buck/Boost变换器飞跨电容电压自平衡分析  

Self-balance Mechanism Analysis of the Flying Capacitor Voltage in the Three-level Buck/Boost Converter With Input and Output Sharing the Ground

作　　者：宋磊[1] 段善旭[1] 米慧瑶 卢沁书 SONG Lei;DUAN Shanxu;MI Huiyao;LU Qinshu(State Key Laboratory of Advanced Electromagnetic Engineering and Technology(Huazhong University of Science and Technology),Wuhan 430074,Hubei Province,China)

机构地区：[1]强电磁工程与新技术国家重点实验室(华中科技大学),湖北省武汉市430074

出　　处：《中国电机工程学报》2023年第15期5983-5994,共12页Proceedings of the CSEE

基　　金：国家重点研发计划项目(2018YFB0106300)。

摘　　要：输入输出共地型Buck/Boost变换器中飞跨电容的平衡机理是变换器正常运行及飞跨电容电压控制的关键。在实际应用中,飞跨电容虽然具有一定的自平衡作用,但是其平衡能力与多种因素有关。在现有的文献中,针对Buck/Boost变换器飞跨电容的自平衡能力与哪些因素相关的问题尚未有深入的分析。因此,基于输入输出共地型Buck/Boost变换器,建立高次谐波模型,定量分析飞跨电容具有自平衡能力的原因;在谐波模型基础上,更进一步分析驱动误差、变换器回路交流阻抗、母线电容、负载电阻及飞跨电容对于飞跨电容平衡能力的影响,指出变换器回路交流阻抗是实际应用中飞跨电容具有自平衡能力的主要因素。最后,在实验平台上对相关分析进行实验验证。Balancing mechanism of a flying capacitor is the key to normal operation and capacitor voltage control in Buck/Boost converters with input and output sharing the ground.In fact,the flying capacitor has a certain degree of self-balance ability.However,affected by many factors,it is hard to be used to replace the active control of flying capacitor voltage.The deep analysis on how the different factors influence the self-balance ability has not been provided in publications.Hence,based on the Buck/Boost converters with input and output sharing the ground,this paper establishes the harmonics model.How the error of drive signals,AC impedance of converter loop,bus capacitor,load resistance and flying capacitor influence the self-balance ability is analyzed quantificationally based on the model.Then,it can be found that AC impedance of the converter loop is the key that contributes to the self-balance ability of the flying capacitor.Finally,the analyses are verified by the experimental results.

关 键 词：Buck/Boost变换器 飞跨电容 自平衡 谐波模型 

分 类 号：TM46[电气工程—电器]