Efficiency Optimized Power-Sharing Algorithm for Modular Battery Energy Storage Systems

Modular Battery Energy Storage systems (MBESSs) enable the use of lower-rated voltage converters and battery modules, simpler management systems. They also improve system's reliability allow flexible power sharing amongst different modules. This paper proposes a power-sharing algorithm which maximizes energy conversion efficiency this storage system, considering state charge (SoC) balancing lifespan. Real time optimum is undertaken based on simple look-up table, whose data was generated via off-line Genetic Algorithm optimization converter's map. To demonstrate proposed algorithms effectiveness, six-module prototype system constructed, each comprising half-bridge converter 10 Ah, 12.8 V, LiFePo4 battery. System testing occurred at levels in both charging discharging modes, using optimized conventional SoC-based methods. The results obtained show that control significantly improves light load compared to equal At high loads, method gives higher than method, an equivalent method.