Non-Linear Loads and K-Factor Analysis on Power Distribution Transformers (Case Study: Lagos State, Nigeria)
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International Journal of Recent Engineering Science (IJRES) |  |
| © 2024 by IJRES Journal | ||
| Volume-11 Issue-5 |
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| Year of Publication : 2024 | ||
| Authors : Titus Olugbenga Koledoye, Abdul-Ganiyu. Adebayo Jumah, Isaac Gbadebo Kolawole, Francis Uwakwe Okoh |
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| DOI : 10.14445/23497157/IJRES-V11I5P102 |
How to Cite?
Titus Olugbenga Koledoye, Abdul-Ganiyu. Adebayo Jumah, Isaac Gbadebo Kolawole, Francis Uwakwe Okoh, "Non-Linear Loads and K-Factor Analysis on Power Distribution Transformers (Case Study: Lagos State, Nigeria) ," International Journal of Recent Engineering Science, vol. 11, no. 5, pp. 7-20, 2024. Crossref, https://doi.org/10.14445/23497157/IJRES-V11I5P102
Abstract
The novel innovation in technology has introduced a large percentage of non-linear loads in electricity networks. The impact can no longer be ignored due to their influence on power quality. Non-linear loads are known to draw distortion currents that generate harmonics, which causes overheating in transformers and often shortens the life span of the transformers and increases maintenance costs. This work examines the influence of non-linear load on distribution transformers by using two 500KVA,11kV-415V distribution substations as a case study. Table 7 shows the harmonics currents data captured at two substations, and the computed Individual Harmonic Distortion (IHD) and Total Harmonics Distortion (THD) for 9 a.m. data collected are reflected in Table 15 for both IEEE and IEC methods. The result shows that the THDs are 34.9% (IEEE) and 32.6% (IEC) for substation A and 56.4% (IEEE) and 48.3% (IEC) for substation B. According to ANSI/IEEEC57.110, any transformer with THD above 5% needs to be de-rated. Also, the K-factor for transformer de-rating computed, shown in Table 16, for the two substations’ transformers, using IEEE methods, reveal a K-factor of 12.89 and 21.69 for substation A and substation B, respectively, while the IEC method values are 11.073 and 17.24 respectively. The need to de-rate the substation transformers for protection and increase the life cycle cannot be over-emphasized.
Keywords
Power quality, Non-linear loads, Power distribution transformer, Harmonics, K-factor.
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