锂离子电池组均衡控制算法研究:由空间到时间的转变

Battery equalization is the key technology of large lithium-ion batteries with direct impact on energy efficiency and security. Traditional battery equalization is realized via electricity energy flow in the spatial domain through energy storage devices or resistive load, which leads to a limit in balancing speed and efficiency. This project presents an active battery equalization method with no need of energy storage devices, which uses the power switching networks to schedule battery charging and discharging in time domain. This project will in-depth research fundamental problems of battery equalization control based on switch network, which has highlight as following: (1) establish mathematical model of the configuration vector of switch networks in the process of charging and discharging; (2) determine the parameter range for equalization and maximum value calculation method; (3) improve the traditional schedule algorithm based on charge order by introducing event driven decision process; (4) propose a battery optimization scheduling algorithm based on battery match and charge compensation to reduce the change of battery voltage and switching times; (5) design two new power switch drive circuit which don’t rely on the cell’s voltage to improve battery security, and reliability and energy efficiency.

电池均衡是大型锂离子电池组应用的关键技术，直接影响能量利用效率与安全性能。传统电池均衡方式应用耗能或储能器件通过空间域能量流动达到电量均衡，在均衡速度、转换效率与电路体积等方面存在较大限制。本项目提出一种无需储能器件的非耗能型电池组均衡方法，在功率回路引入开关网络，通过在时间域上优化工作时长与次序实现电池均衡。本项目将深入研究开关网络式电池组均衡控制的基础问题，提出充放电均衡控制过程中配置向量的数学模型，确定电池组达到均衡的参数范围与最大值计算方法。在此基础上，首先改进基于电量排序的电池调度算法，采用事件驱动的决策更新机制克服传统时钟驱动模式开关切换频率高的弊端；然后设计一种基于电池匹配与电量补偿的优化调度算法，最大限度减少电池组电压波动与开关切换频率；最后研究通过双极性或隔离电源实现不依赖于电池自身电压的MOSFET驱动电路，应用软硬件优化配合，提高电池组运行的安全性、可靠性与能量效率。