【作者】 尹政；

【导师】 程勇；

【作者基本信息】 山东大学 ， 动力机械及工程， 2011， 硕士

【摘要】 电动汽车具有节能与环保的双重优势,近年来受到世界各国的重视,发展迅速。但动力电池管理系统却是制约电动汽车发展的瓶颈。准确预测电池剩余电量(SOC)以及实现电池组的均衡充放电,延长电池的使用寿命是电动汽车电池管理系统需要解决的问题。对动力电池组实施有效监测和管理,对于解决上述问题具有重要的意义,可有效推动电动汽车的实用化、产业化发展。课题针对磷酸铁锂动力电池的特点,开发了一套电池管理系统试验台。该试验台由控制模块、采集模块和工控机组成,可实现对电池组各单体电池电压、测点温度以及电池组总电压、总电流的监测、采集和数据处理。此外,该电池管理试验台还可通过功率输出放大电路、开关量输入调理电路,实现充电机、温控设备的控制以及接收外部状态信号等功能,使电池管理试验台的功能更为完善。课题对电池管理试验台的功能及工作可靠性进行了实验验证。使用充电机和放电仪分别以不同电流对动力电池组进行了充放电实验,对电池组的总电压和各单体电池电压进行了实时监测,分析了在相同的剩余电量(SOC)下,充放电电流大小对电池电压的影响。使用电流积分法对SOC的变化量进行估算,针对实验采集的一段电流曲线,在不同采样频率和采样精度下对其计算准确性进行研究,为电池管理系统SOC估算的实际应用提供依据。课题还分析了由于单体电池的不一致性对电池组可放出电量的影响。在使用电池管理试验台对电池运行数据进行监测的过程中,电池组的各单体电池在充放电时的电压存在不一致性,说明电池组串联使用时存在不均衡现象。动力电池组不均衡性的危害很大,它不仅降低了电池组的使用效率而且会缩短循环使用寿命。为解决电池组的不均衡性,人们对均衡充放电的各种方法开展了研究,但目前大多都处于理论分析阶段。本课题采用MATLAB/Simulink搭建动力电池模型和部分均衡充放电电路模型,利用此模型对均衡充放电进行仿真,将各种均衡方法的仿真结果进行对比,分析各自的优缺点,为均衡充放电电路的实际应用提供理论依据。更多还原

【Abstract】 As the dual advantages of energy saving and environmental protection, electric vehicles are developing rapidly worldwide in recent years. However, battery management system is a bottleneck restriction to electric vehicles development. Electric vehicle battery management system necessarily solves problems on State of Charge (SOC) estimation, balanced charge and discharge achievement and prolonging battery life span. The effective monitoring and management of battery pack for solving problems forenamed have important theoretical significance and practical value, which can effectively promote the practicality and commercialization of electric vehicles.According to characteristics of the lithium iron phosphate battery, a battery management system testing platform is designed to detect and process the battery performance parameters, including the module voltage, temperature, the pack voltage and current. In addition, the battery management system testing platform has more perfect functions, realization of battery charger and temperature controlling and status signals receiving by relay controlling and digital input signal conditioning.The function and reliability of the testing platform are validated. Charge and discharge experiments are conducted at different current using charger and discharge instrument, the real-time monitoring of module voltage and the pack voltage is carried on and the effect of current to the battery voltage in the same SOC is analyzed. The current integration method is to estimate the SOC variable, for calculation accuracy of SOC with different sampling frequency and accuracy to the current experimental curves collected is studied to provide the basis for practical application of the battery management system SOC estimation. Project also analyzed the inconsistencies in the single cell battery pack could be released on the impact of electricity.The imbalance of battery packs in series using exists, which is validated with the inconsistencies of module voltage monitored by the testing platform during the battery charge or discharge process. Battery imbalance is harmful to the battery pack, which not only reduces the battery pack efficiency, but also will shorten its life cycle. To solve the imbalance of the battery pack, various methods of balanced charge and discharge are carried out, but mostly in the theoretical analysis phase. By model building of battery and balanced model using MATLAB/Simulink, the charge and discharge is simulated. Varieties of charge and discharge simulation results are compared and the advantages and disadvantages are analyzed to provide theoretical basis for practical application.更多还原