Assessment of Total Harmonic Distortion for Power Quality Improvement in Low Voltage Distribution Networks

Ensuring high power quality in low-voltage distribution networks is crucial for efficient and reliable electricity supply. However, the increasing presence of nonlinear loads introduces harmonics into the power system network (PSN), leading to waveform distortions that degrade power quality. These harmonics, primarily generated by electronic devices, motors, generators, and transformers, contribute to power losses, system instability, and unbalanced load distribution at feeder pillars, ultimately affecting service delivery. This study aims to assess the Total Harmonic Distortion (THD) levels in a distribution network powered by a distribution transformer (DT) from a Nigerian power utility company, with a focus on residential, commercial, and smallscale industrial consumers. A Fluke energy analyzer was deployed at the secondary side of the DT, with all necessary calibrations and presetting completed before data acquisition. The collected harmonic data was subsequently processed and analyzed using spreadsheet software to determine the extent of waveform distortion. The results provide insights into the harmonic levels present in the distribution network and their impact on power quality. Findings from the analysis highlight the severity of harmonic distortions, their potential consequences on equipment performance and network stability, and the need for appropriate mitigation strategies. This assessment serves as a foundation for recommending power quality improvement measures to enhance the reliability and efficiency of low-voltage distribution networks.