Strategy for compensation of unbalanced powers in LV residential distribution networks using distributed single-phase battery systems

Abstract

Unbalanced powers, due to high penetration of single-phase PV rooftop systems and loads into a low voltage residential distribution system, can result in large neutral current and neutral to ground voltage rise. This paper proposes a distributed cooperative dynamic power balancing control strategy to mitigate the unbalanced powers using single-phase battery storage systems distributed in the low voltage residential distribution system. First, a distributed clustering algorithm is used to aggregate the battery storage systems connected to the same phase into the same cluster. Within each cluster, a distributed average grid power calculation algorithm calculates the average grid power exchanged with the corresponding phase. Then, the proposed distributed cooperative dynamic power balancing control strategy is applied to balance the unbalanced powers using the single-phase battery systems at the given bus while minimizing the power exchanged with the grid. The battery systems’ charge/discharge constraints, power constraints and willingness of the battery systems’ owners to participate in the power balancing control strategy are considered. Performance of the proposed strategy is verified using Real-Time Digital Simulator (RTDS).