Optimal Sizing and Placement of Distributed Generators in Unbalanced Distribution Networks: An Analytical Perspective

In modern power systems, integrating distributed generation (DG) is essential to meet growing energy demands while optimizing operational and financial efficiency. However, arbitrary placement of DG units can significantly impact on power losses and voltage profiles of the network, depending on their capacity and location. Precise optimization of both the location and capacity of DG units is therefore crucial to maximizing their benefits and mitigating over-voltage issues. This paper presents an analytical approach that employs an Exact Loss Formula to determine the optimal capacity and location for DGs, specifically within unbalanced practical distribution networks, which remains an area not thoroughly addressed in previous literature. The proposed method is validated on the standard IEEE 33-bus network and further applied to a real-world distribution network in Kurunegala District, Sri Lanka, with rooftop solar as the DG. Test results demonstrate the effectiveness of the proposed method in minimizing power losses and addressing voltage-related challenges in unbalanced distribution systems.