Fuzzy-Controlled Hierarchical Active Blancing Circuit for Battery Systems

To address the inconsistency issues in large-scale, series-connected battery packs, this paper presents a hierarchical active balancing topology based on a fuzzy control strategy. The topology partitions the battery pack into modules, each using a buck-boost converter. A single inductor balancing circuit connects the modules, and an auxiliary power supply facilitates balancing. The fuzzy controller dynamically optimizes the switching tube driving timing, significantly reducing the control complexity in multi-battery applications. Simulation results demonstrate that the proposed topology achieves balancing during charging and discharging in 334s and 307s, respectively, shortening balancing time and improving efficiency by $105 \%$ and $129 \%$ compared to traditional topologies, which require 685s and 702s for the same processes.