Integrated SoC and SoH Balance Strategy of Battery Packs with Reconfigurable Series Topology
LI Qi-ru, Wang Zhenxiong, Hao Yi, Hongwei Zhou, Zhao Liangliang, Fang Zhuo · 2024
With the rapid expansion of renewable energy generation, energy storage is receiving widespread attention. In high-capacity storage inverters, multiple battery packs are series connected on the DC side. However, the discrepancies in the battery state of battery packs can diminish available capacity and expedite the aging of certain battery packs, even posing security risks. Balancing the state of battery packs is crucial for battery energy storage system. To address this challenge, this paper proposes a reconfigurable series topology along with a DC/DC converter to regulate the state of charge (SoC) and the state of health (SoH) of each battery pack. Through this approach, the consistency of battery packs’ SoC is enhanced, while mitigating the life degradation of low SoH battery packs. Comprehensive analysis and simulation results are presented to validate the effect of the proposed topology and control strategy.