arXivDaily arXiv每日学术速递 周一至周五更新
arXiv 2312.03097eess.SYcs.SY
收藏

单体间存在差异时含并联单体的电池模组健康状态估计

State of Health Estimation for Battery Modules with Parallel-Connected Cells Under Cell-to-Cell Variations

Qinan Zhou, Dyche Anderson, Jing Sun

AI总结:

针对并联单体差异下仅有模组测量时的SOH估计难题,提出基于信息论特征选择与RVR的ICA/DVA方法,实现高精度、带可信区间且适合车载部署的稀疏估计。

摘要:

对于单体并联连接的锂离子电池模组,健康状态(SOH)估计是一个具有挑战性的问题,尤其是在存在单体间差异时。增量容量分析(ICA)和差分电压分析(DVA)在单体层面是有效的,但当仅有模组层面的测量值可用时,仍缺少一种可将其推广到模组层面SOH估计的通用方法。本文提出一种新方法,并证明通过从模组层面ICA和DVA中系统地选择多个特征,在存在单体间差异的情况下,能够以高精度和高置信度估计模组层面SOH。首先,提出一种基于信息论的特征选择算法,以寻找用于模组层面SOH估计的最优特征集。其次,提出一种基于相关向量回归(RVR)的模组层面SOH估计模型,在保持模型稀疏性的同时提供点估计和3σ可信区间。随着纳入更多所选特征,所提方法以更高模型复杂度为代价,获得更好的估计精度和更高置信度。当应用于大型实验数据集时,所提方法及所得稀疏模型给出的模组层面SOH估计具有0.5%的均方根误差和1.5%的平均3σ值。由于所有训练过程均在离板状态下完成,所提方法用于车载实现时计算复杂度较低。

英文摘要:

State of health (SOH) estimation for lithium-ion battery modules with cells connected in parallel is a challenging problem, especially with cell-to-cell variations. Incremental capacity analysis (ICA) and differential voltage analysis (DVA) are effective at the cell level, but a generalizable method to extend them to module-level SOH estimation remains missing, when only module-level measurements are available. This paper proposes a new method and demonstrates that, with multiple features systematically selected from the module-level ICA and DVA, the module-level SOH can be estimated with high accuracy and confidence in the presence of cell-to-cell variations. First, an information theory-based feature selection algorithm is proposed to find an optimal set of features for module-level SOH estimation. Second, a relevance vector regression (RVR)-based module-level SOH estimation model is proposed to provide both point estimates and three-sigma credible intervals while maintaining model sparsity. With more selected features incorporated, the proposed method achieves better estimation accuracy and higher confidence at the expense of higher model complexity. When applied to a large experimental dataset, the proposed method and the resulting sparse model lead to module-level SOH estimates with a 0.5% root-mean-square error and a 1.5% average three-sigma value. With all the training processes completed offboard, the proposed method has low computational complexity for onboard implementations.

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

↑