Logic‐Based Battery Management System for Second‐Life Batteries Enabling Rapid Fault Mitigation in Malaysian Photovoltaic Integrated Distribution Networks

ABSTRACT With increasing photovoltaic (PV) penetration, distribution networks are increasingly exposed to voltage instability and fault‐related disturbances due to the stochastic nature of solar generation. Second‐life batteries (SLBs), repurposed from retired electric‐vehicle (EV) batteries, offer a cost‐effective and sustainable Energy Storage solution for enhancing grid resilience. However, the reliable deployment of SLBs requires effective battery management strategies capable of addressing performance variability and operational constraints associated with battery aging. This study presents a logic‐based battery management system (BMS) for integrating SLBs within an AC–DC–AC converter topology to provide rapid fault mitigation in PV‐integrated Malaysian distribution networks. The SLB is modeled at the cell level using a first‐order RC equivalent circuit, with model parameters identified from experimental characterization of retired EV battery cells. A hierarchical sizing methodology is developed to configure the SLB Energy Storage system from the cell level to the module and system levels. To enhance operational reliability and prolong battery lifespan, the proposed BMS incorporates active inductive cell balancing and low C‐rate charging within a defined safe operating envelope (SOE). The simulation results demonstrate that the proposed system achieves state‐of‐charge equalization within approximately 6 min with a balancing efficiency of 95.6%, while the low‐rate charging strategy achieves 99.18% charging efficiency. During fault conditions, the SLB‐converter system provides rapid voltage support, achieving fault mitigation within 5.258 ms with a round‐trip efficiency of 86.33%. These results highlight the potential of second‐life battery systems as a cost‐effective and fast‐response alternative to conventional compensators for improving stability in photovoltaic‐integrated distribution networks.