This article proposes and compares a new family of low-complexity control schemes for the fast charge of lithium-ion (Li-ion) battery cells accounting for degradation constraints. These schemes are based on a two-level architecture, where a low-level linear quadratic regulator (LQR) ensures stability and fast tracking of the applied reference, while an outer control layer, based on an explicit reference governor (ERG), enforces constraints satisfaction by manipulating the applied reference of the lower level. The ERG is based on the construction of a suitable Lyapunov level set contained inside of linear constraints. The main challenge to build a performing ERG for the fast charge of Li-ion batteries is how to choose a convenient Lyapunov function for nonconvex constraints arising from the electrochemical model of the battery. This article proposes and compares four different approaches to obtain performing Lyapunov functions for a concave constraint evaluating the impact on the charging time of a Li-ion battery and on the required computational time. Experimental validations on commercial lithium-cobalt oxide (LCO) battery cells (Turnigy nano-tech 160 mAh) show a tradeoff between the four methods computational time and the charging time.

中文翻译：

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基于显式参考调节器的锂离子电池的低复杂度快速充电策略

本文针对锂离子 (Li-ion) 电池单元的快速充电提出并比较了一系列新的低复杂度控制方案，以考虑退化限制。这些方案基于两级架构，其中低级线性二次调节器 (LQR) 确保应用参考的稳定性和快速跟踪，而基于显式参考调控器 (ERG) 的外部控制层强制执行约束通过操纵较低级别的应用参考来满足。ERG 基于构建一个包含在线性约束内的合适的李雅普诺夫水平集。为锂离子电池的快速充电构建执行 ERG 的主要挑战是如何为电池电化学模型产生的非凸约束选择方便的 Lyapunov 函数。本文提出并比较了四种不同的方法来获得执行李雅普诺夫函数的凹约束，评估对锂离子电池充电时间和所需计算时间的影响。对商用锂钴氧化物 (LCO) 电池单元（Turnigy nano-tech 160 mAh）的实验验证显示了四种方法计算时间和充电时间之间的权衡。