A Dynamic Power Balancing Method for Aircraft Battery Packs Based on Fuzzy Droop Control

Electric aircraft is a future development trend, but the performance of batteries restricts the application of electric aircraft. The balance of distributed battery packs has a significant impact on the safety of electric aircraft. This paper proposes a dynamic power balancing method for source-load separation between battery packs, which is based on fuzzy logic control and optimized droop control with variable parameters. By defining the criteria for "sources" and "loads" setting the start and stop balancing conditions, this method enables faster balancing speeds, while achieving smaller energy transfer between battery groups. The dynamically varying balancing current prevents high current charging before achieving balance, reducing thermal stress during charging and decreasing battery degradation. Additionally, this method enables energy balancing in the aircraft power system under fewer modes, minimizing frequent transitions between balancing modes. It also eliminates the voltage deviation caused by traditional droop control in the battery balancing system, enhancing the reliability of power supply. An experimental platform including 4 groups of 48V battery packs is built to validate the proposed control method. After comparative experiments with traditional methods, it shows that the proposed method has faster dynamic balancing speed, more flexible mode conversion, and no deviation in DC bus voltage.