Optimal Operation of Grid-Forming-Controlled PV and Energy Storage Converters in Low-Voltage Distribution Networks

Abstract

To address voltage fluctuations, low renewable energy permeability, and high power loss in low-voltage distribution networks (LVDNs) integrated with photovoltaic (PV) and energy storage systems (ESSs), a Chaotic Particle Swarm Optimization (PSO)-based hierarchical optimal operation method is proposed. Firstly, the mathematical model for grid-forming control (GFM)-based PV and ESSs in LVDNs is developed. Then, the multi-objective optimization problem is formulated to: (1) minimize voltage deviation, (2) maximize PV generation power, and (3) minimize power losses. Next, the objectives are ranked based on priority, and the multi-objective optimization problem is split into several single-objective sub-problems, each solved with the chaotic PSO algorithm. Several test studies confirm that the proposed strategy achieves faster convergence (68 iterations vs. 142, reducing total computation time by 36.9%), along with a marginal accuracy improvement over standard PSO. Finally, both simulation and hardware-in-the-loop (HIL) experimental results demonstrate the effectiveness and reliability of the proposed operation scheme in LVDNs.