A Multi‐Layer Transactive Co‐Simulation Framework for Battery Energy Storage Fleet Phase Balancing and Asset Protection in Unbalanced Tropical Grids

ABSTRACT

The widespread deployment of residential battery energy storage systems (BESS) introduces complex control challenges in tropical low‐voltage distribution networks, where high ambient temperatures accelerate transformer degradation. This study presents a four‐layer cyber‐physical transactive energy co‐simulation framework for coordinating a decentralised fleet of 55 residential BESS assets. The architecture integrates a double‐auction market driven by thermal‐ and voltage‐sensitive distribution locational marginal pricing benchmarked against an omniscient, centralised non‐linear programming (NLP) optimisation solver. Modelled on an unbalanced Ghanaian network, the framework mitigates voltage unbalance factor violations and transformer insulation wear. Quantitative results show that while uncoordinated baselines and rigid centralised overrides fail to prevent severe thermal core stagnation (0.0198 h daily ageing loss), the proposed dynamic, feedback‐responsive transactive framework reduces diurnal insulation degradation to 0.0184 h (a 7.1% reduction in thermal ageing loss) while preserving data privacy. In comparison, the centralised NLP benchmark established a centralised optimisation limit, restricting ageing loss to 0.0155 h (a 21.7% reduction in thermal ageing loss). This study validates that market‐driven, incentive‐based hierarchical control can help reconcile decentralised prosumer autonomy, network phase balancing and utility infrastructure longevity under stringent operating constraints.