A Modularized Equalizer for Series-Connected Batteries Based on Push-Pull Converter
Liu Qianyi, Xu Shungang, Xu Jianping, Li Xiaolong, Qin Fuban
The Ministry of Education Key Laboratory of Magnetic Suspension Technology and Maglev Vehicle School of Electrical Engineering Southwest Jiaotong University Chengdu 610031 China
Abstract：Overcharge and over-discharge of batteries may result in shorter lifetime and higher potential of security risk when they are connected in series to meet load voltage requirements. Therefore, equalization circuits are required for a series-connected battery string to eliminate individual difference among batteries in the battery pack. In this paper, a modularized equalizer based on push-pull converter is proposed. The proposed equalizer circuit can transfer energy from high voltage batteries to low voltage batteries directly to shorten the transmission path under synchronous control. Besides, it eliminates the magnetic coupling effects caused by multi-winding transformer and increases the circuit expansibility. In this paper, operating principles of the proposed circuit are analyzed. The performance comparisons with existing equalizer circuits are carried out. Finally, the theoretical analysis results are verified by experimental results.
刘倩怡, 徐顺刚, 许建平, 李小龙, 覃福班. 一种基于推挽变换器的模块化电池均衡电路[J]. 电工技术学报, 2018, 33(14): 3213-3221.
Liu Qianyi, Xu Shungang, Xu Jianping, Li Xiaolong, Qin Fuban. A Modularized Equalizer for Series-Connected Batteries Based on Push-Pull Converter. Transactions of China Electrotechnical Society, 2018, 33(14): 3213-3221.
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2018, Vol. 33 
