基于任意单体间能量转移的高效均衡策略

An Efficient Equilibrium Strategy Based on the Energy Transfer Among Arbitrary Cells

基于任意单体间直接转移能量均衡拓扑,提出一种新型高效均衡策略。根据单体充放电特性曲线,采用安全系数重新划定分区,设定整体剩余电量归属函数,并设定分段阈值修正因子函数;理论推导阈值中心点搜索过程的变化规律,以剩余电量均值为起点,采用预搜索方法迅速判定搜索方向,从而快速确定最优值;建立转移信息矩阵与转移过程模型,利用线性规划方法求解转移能量最优路径。该策略以剩余电量为均衡指标,对六节串联锂离子单体进行充放电均衡对比实验。实验数据表明,较其他均衡方案,本方案可以更高效、低耗地完成均衡目标,有效改善电池组的工作性能。

A novel efficient equilibrium strategy was proposed based on the direct transfer of energy equalization topology among arbitrary cells.The safety coefficient was adopted to redefine the partition of battery state according to the charge-discharge characteristic curve of cell.Then the attribute function of battery remaining capacity and segmented threshold correction factor function were set.Theoretical derivation method was used to find out the changing laws of searching threshold center.Taking the average remaining capacity of the battery as the starting searching point,an efficient way called pre-search was used to quickly determine the searching orientation and the optimal starting value.The transformation matrix and transfer process model were established,and linear programming idea was used to solve the optimal path of energy transfer.In this strategy,the remaining capacity was set as the equilibrium indicator to carry out a comparison experiment of charge-discharge equilibrium on six lithium-ion cells in series.The experimental data show that this scheme can achieve equilibrium target with higher efficiency and lower power consumption,thereby effectively improving the performance of the battery.