纯电动汽车动力锂电池均衡充电的研究  

Charge equalization of Li-ion battery for electric vehicles

作　　者：郭军[1] 刘和平[1] 徐伟[1] 刘平[1] 

机构地区：[1]重庆大学输配电装备及系统安全与新技术国家重点实验室,重庆400044

出　　处：《电源技术》2012年第4期479-482,共4页Chinese Journal of Power Sources

基　　金：中央高校基本科研业务费资助项目(CDJXS11151156)

摘　　要：针对电动汽车动力电池组中单体电池的不均衡将减少电池使用寿命和电动车单次充电行驶距离的问题,设计了均衡充电装置。通过对16节串联电池组的大量充放电试验得到电池电压之间的分散性曲线,并分析了均衡充电的必要性。根据锂电池充电特性,对电池不均衡度进行了数学建模,并提出单体电池SOC(State of charge)相对浓度和伪均衡的概念。均衡充电主电路采用反激变换器完成高频变压器的设计,同时通过软件实现均衡装置的自启动和结束,并采用两点标定法来提高A/D采样精度。最后采用Saber仿真软件和实验对设计进行了验证。结果表明:实现了恒流和恒压控制,并将电池分散性降低了61.86%。The unbalance of Li-ion cells in the same battery pack may limit the life of batter and the operating range of once charge, so the charge equalization convertor was designed. The dispersion curve of voltage was obtained by testing battery, which was made up 16 cells. The necessity of charge equalization was analyzed particularly. According to electrical properties of Li-ion cells, the unbalance of a battery was discussed, and a mathematical model was established. Two concepts were presented： relative concentration of single battery for SOC （State of Charge）, and pseudo-equilibrium for battery. The high-frequency transformer adopted flyback converter and start and end of charge equalization was controlled by software. The accuracy of ND sample was improved by two point method of calibration. Finally, the result of simulation and experiment show that constant voltage and current control is achieved and the dispersion is decreased by 61.86%.

关 键 词：纯电动汽车 锂电池 均衡 充电 反激变换器 不均衡度 伪均衡 恒压控制 恒流控制 

分 类 号：TM912.1[电气工程—电力电子与电力传动]