Engineering-Based Steady-State Analysis of Voltage Profile and Power Flow in Three-Phase Unbalanced Distribution Systems

Year 2025, Volume: 5 Issue: 3, 176 - 184, 30.10.2025

Fatma Avli Fırış

https://doi.org/10.5152/tepes.2025.25023

https://izlik.org/JA47UD83FM

Abstract

This study presents a detailed engineering-based assessment of the steady-state electrical behavior of three-phase unbalanced distribution systems. The modeling and simulation were conducted on a professional-grade engineering platform, enabling high resolution analysis of phase asymmetries inherent in the system. Power flow distribution, voltage profiles, regulator responses, and system losses were examined on a per-phase basis to capture the impact of asymmetrical loading conditions. According to the simulation results, voltage unbalance factors reached up to 1.2% with voltage deviations exceeding 2.5% at certain nodes, and significant drops were observed especially in phase C at terminal busbars. Most of the total active and reactive power losses were concentrated in heavily loaded phases and long feeder branches, and these losses were calculated as 111.06 kW and 324.65 kVAr, respectively. The findings provide a technically based reference for understanding the voltage behavior in unbalanced systems. In addition, this study contributes to the development of phase balancing strategies, regulator control algorithms, and advanced load integration scenarios within distribution networks. The findings provide a technically based reference for understanding the voltage behavior in unbalanced systems and serve as a foundation for future investigations into harmonics, probabilistic load dynamics, and renewable energy integration.

Keywords

Distributed system , power flow , unbalanced system , voltage profile

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