Load Flow Analysis for Abuja Electricity Distribution Company (AEDC) - Gwarinpa Line 1 Radial Distribution Network using Backward/Forward Sweep Algorithm

Abstract

This research conducted a comprehensive load flow analysis of the 11kV AEDC Gwarinpa Line 1 radial distribution network using the Backward/Forward Sweep (BFS) algorithm implemented in MATLAB, followed by extensive simulation of optimisation strategies based on contemporary Nigerian research methodologies. The study addressed unique challenges of radial distribution systems, including high resistance-to-reactance ratios and unbalanced loading conditions that traditional power flow methods struggle to handle effectively. The research developed an accurate model of the 74-bus Gwarinpa network, implemented the BFS algorithm, and performed extensive analyses under various loading scenarios ranging from current conditions to potential future demand levels. The initial findings revealed that whilst the network currently operates within acceptable voltage limits (minimum voltage 0.9485 per unit), it faces significant challenges with increased loading. At 32.10% loading, the average voltage drops below standard thresholds to 0.91 per unit, whilst losses increase nearly fivefold to 244.43 kW. The analysis identified critical areas for improvement, including concentrated losses in initial branches, uneven loading distribution across feeders, and voltage regulation concerns under growth scenarios. Based on these findings, the research implemented and simulated a comprehensive optimisation strategy encompassing strategic capacitor placement, conductor upgrades, solar PV integration, and load balancing measures. The simulation results demonstrate exceptional technical and economic performance: a total investment of ₦192.73 million generates annual returns of ₦45.26 million, achieving a 3.4-year payback period with a 29.4% return on investment. The optimised network exhibits remarkable improvements including 52.39% power loss reduction (from 53.43 kW to 25.44 kW), 1.27% voltage profile enhancement (minimum voltage improved from 0.9485 to 0.9605 per unit), and 22.1% reduction in maximum bus loading. The strategic interventions comprise: 200 kVAr capacitor installation across four critical buses (₦3.90 million investment, 0.8-year payback); conductor upgrades for three high-loss branches (₦4.55 million investment, 0.5-year payback); and 307.1 kW solar PV integration across 25 strategic locations (₦184.28 million investment, 6-year payback). These measures collectively achieve substantial environmental benefits, including 231.2 tonnes annual CO₂ reduction equivalent to removing 50 cars from roads, and renewable generation meeting 8.3% of network demand.