Design Method of 6-Element Boundary Gain for LLC Resonant Converter of Electric Vehicle

IEEE Access

Chaochao Shen¹  Yang Zhang¹  Yining Zhang¹  Yiwen Tang¹  Hao Zhong² 

[1] College of Electrical and Information Engineering, Hunan University of Technology, Zhuzhou, China;Hubei Key Laboratory of Cascaded Hydropower Stations Operation and Control, China Three Gorges University, Yichang, China;

关键词: LLC resonant converter;    zero-voltage switching;    wide range output;    battery charger;    electric vehicle;   

DOI  :  10.1109/ACCESS.2020.3028941

来源: DOAJ

【 摘 要 】

In the application of on-board chargers, LLC resonant converters need to work in multiple operating modes to achieve wide-range output requirements. For the most commonly used single-phase and three-phase LLC topologies, the time domain expressions of all possible operating modes are introduced to predict voltage and current behaviors. Based on the mode analysis, the 6-element boundary gain design method is proposed to design a wide gain range LLC resonant converter. The resonant current is used as the basis for ZVS judgment and the transformation trend of ZVS in the full operating range is given. Through reasonable distribution of the boost region and the buck region, the resonant devices can be designed more appropriately to achieve lower conduction loss and higher efficiency. Finally, the prototypes of 3.3kW and 6.6 kW are built to verify the theoretical analysis of the method in single-phase LLC and three-phase LLC.

【 授权许可】

Unknown