ORCID
https://orcid.org/0000-0002-0287-7063
Abstract
The increasing demand for decentralized, reliable electricity in rural Sub-Saharan Africa has catalyzed the deployment of minigrids as an intermediate electrification strategy. This study investigates two solar photovoltaic (PV) mini-grids: Kyamugarura and Kanyegaramire, located in western Uganda, approximately 3km apart. Each mini grid initially consisted of 13 kW installed photovoltaic (PV) capacity, supplying power to households and small businesses. Due to rising demand and regular evening blackouts, both mini-grids are being upgraded to 57 kWp each. The integration of these upgraded systems into the national utility grid is proposed and simulated to evaluate performance improvements under two medium-voltage interconnection options: 11 kV and 33 kV. Using DIgSILENT PowerFactory software, the study models and simulates both configurations to analyze steady-state load flow, voltage regulation, power losses, short circuit behavior, and transient dynamic response under realistic loading conditions. Simulation results show that while both configurations comply with IEEE voltage deviation standards (±5%) (IEEE Standard 1547-2018), the 33 kV network yields lower total system losses, lower peak losses during peak hours, and significantly reduced short-circuit current levels at the point of common coupling. Transient simulations further reveal faster voltage and frequency recovery in the 33 kV system following three-phase fault events, demonstrating better system resilience. The 33 kV configuration also requires less complex and less costly protection schemes. The findings support the adoption of 33 kV interconnection for minigrids exceeding 50 kW in rural electrification strategies. The paper concludes with practical recommendations for national electrification programs, including voltage standardization, simulation-based planning, and smart component integration. These insights contribute to ongoing policy and infrastructure development initiatives in East Africa and other developing regions.
Recommended Citation
Mutesi, P., Kihwele, S., & Matee, E. (2026). Load Flow and Fault Performance Evaluation of Interconnected Minigrids in Uganda Using DIgSILENT PowerFactory. Tanzania Journal of Engineering and Technology (TJET), 45(1), 173-184. https://doi.org/https://doi.org/10.65085/2619-8789.1279
Publisher Name
University of Dar es Salaam
Included in
Controls and Control Theory Commons, Electrical and Electronics Commons, Energy Systems Commons, Other Operations Research, Systems Engineering and Industrial Engineering Commons, Power and Energy Commons