摘要:能源紧张和气候恶化使具有节能环保优势的电动汽车受到了全球的关注。汽车采用电能代替煤炭、石油等化石燃料作为动力,是未来交通的唯一长远解决方案。随着传统锂离子电池在安全性方面的缺点,磷酸铁锂电池的诞生满足了人们对安全性高的动力电池的需求。确保电动汽车良好运行的条件之一是对电池剩余容量(SOC)进行精确地估计。电池剩余电量SOC估计一直是电池管理系统的核心,是反映电池运作状态的主要参数,为整车控制策略提供判断依据。本课题以动力电池磷酸铁锂为研究对象,提出了选取Freescale新型汽车级的32位单片机S9KEAZ128AMLK为中央控制器,采用SOC估算方法中开路电压法和安时积分法相结合的方法应用于SOC估算的方案。该方案利用电池信息采集板对电池的电压、电流及温度等信息进行采集,同时利用对应的上位机进行在线实时显示,利用Matlab拟合电池的充放电数据。根据电池充放电曲线分析电池的外特性,最终得到了满意的SOC估算精度。 32386
毕业论文关键字:电动汽车;磷酸铁锂电池;剩余电量(SOC)
Research On SOC Estimation Method Of LiFePO4 Battery Based On S9KEAZ128AMLK
Abstract:Energy shortage and climatic degeneration make the electric cars with the advantage of environmental protection get the world’s attention. Instead of fossil fuels like oil, this kind of car takes electrical energy as power, which is the only long-term solution for future traffic. As the traditional lithium batteries have low security, the birth of lithium-iron phosphate battery meet people’s requirements for power battery with high safety. One of the conditions to make sure that the electric car is in good running is the accurate estimation of SOC(state of charge).SOC estimation has always been the core of the battery management system(BMS). it is an important parameter to reflect the battery operation state, providing a criterion for the vehicle control strategy. In this paper, we choose the lithium iron phosphate battery as the research object, a new 32bit MCU S9KEAZ128AMLK produced by Freescale is proposed as the CPU, then a comprehensive scheme of SOC measuring method has been raised, which is the combination of Ah method and open circuit voltage. In this scheme, a battery information acquisition slabs was used to collect the information such as voltage of the battery、current and temperature, at the same time by using a corresponding Upper computer display these information online real-time , then use Matlab fit the battery charge and discharge data. Finally, according to the battery charge and discharge curve analysis of external characteristic of the battery, a satisfied estimation accuracy of the SOC is obtained.
KeyWords:electric vehicle; Lithium iron phosphate battery; state of charge (SOC)
目 录
摘要 I
Abstract II
1. 引言 1
1.1 课题背景 1
1.2 主要研究内容和方法 2
1.3 国内外研究现状与水平 2
1.3.1 磷酸铁锂电池国内外研究现状 2
1.3.2 电池SOC 估算国内外研究现状 3
1.4 本课题研究的意义 5
2. 磷酸铁锂电池的介绍 6
2.1 磷酸铁锂电池的研究进展 6
2.2 磷酸铁锂电池内部结构及工作原理 6
2.3磷酸铁锂电池与其他电池的比较 8
2.4 磷酸铁锂电池的特性 10
2.4.1 开路电压特性 10
2.4.2 工作电压特性 11
2.4.3 电池的循环特性 12
3. 磷酸铁锂电池SOC 14
3.1 电池SOC定义 14
3.2 SOC的影响因素 14 基于S9KEAZ128AMLK的磷酸铁锂电池的SOC估计:http://www.youerw.com/zidonghua/lunwen_29081.html