Comparative techno-economic analysis of distribution network reinforcement and LEC flexibility for overvoltage regulation

This paper aims to investigate the economic viability of line upgrades, battery energy storage systems (BESS), optimized active photovoltaic (PV) power curtailment, and the utilization of reactive power from PV inverters to handle overvoltage problems in distribution grids. To do this, we propose a line upgrade investment model to pinpoint lines requiring reinforcement. An optimization model is developed for BESS to optimize charge/discharge schedules for demand and generation balancing. To minimize the need for active PV power curtailment, an optimization based curtailment strategy is also proposed, which ensures grid voltage constraints are met. Simulations on a real-world distribution grid highlight the increasing costs of line upgrades with higher PV penetration. While simulations indicate BESS can technically address overvoltage issues, they may not be the most cost-effective approach, particularly compared to active PV curtailment and reactive power injection from PV inverters.