Data-Driven Condition Assessment and Remaining Life Prediction of Low-Voltage Distribution Transformers Using Insulation Resistance Measurements: A Case Study of Ajayi Crowther University Distribution Network

References

[1] M. A. Salam, "Fundamentals of Electrical Power Systems Analysis," Springer, Singapore, 2020.

[2] P. Brown, L. Davis, and R. Thompson, "Insulation deterioration and safety concerns in electrical equipment,” International Journal of Electrical Engineering, vol. 62, no. 4, pp. 231–245, 2021.

[3] A. Smith and M. Johnson, "Principles of insulation resistance testing,” Electrical Systems Review, vol. 28, no. 2, pp. 104–112, 2020.

[4] T. Williams, "Principles of insulation resistance in electrical systems," International Journal of Electrical Engineering, vol. 44, no. 1, pp. 57–68, 2019.

[5] T. Anderson, "Factors influencing insulation resistance," Journal of Electrical Maintenance, vol. 34, no. 2, pp. 123–135, 2022.

[6] J. White, et al., "Aging and degradation of insulation materials in hybrid electric systems," Journal of Applied Electrical Engineering, vol. 77, no. 4, pp. 118–132, 2023.

[7] P. Davis and R. Thompson, "Digital testing devices and automated insulation resistance testing,” Journal of Electrical Systems, vol. 50, no. 4, pp. 312–324, 2020.

[8] IEEE Standards Association, "IEEE Standard Test Code for Liquid-Immersed Distribution, Power, and Regulating Transformers," IEEE Std C57.12.90-2015, 2015.

[9] J. Harris, "Improving insulation resistance in high-voltage systems,” Journal of Electrical Power Systems, vol. 59, no. 3, pp. 109–120, 2021.

[10] Z. Yang and X. Wang, "Insulation resistance testing in hybrid electric appliances,” Journal of Energy Systems, vol. 54, no. 5, pp. 214–226, 2020.

[11] S. Miller and R. Lee, "The impact of test voltage on insulation resistance testing,” Journal of Electrical Testing, vol. 63, no. 1, pp. 42–55, 2022.

[12] L. Jin, D. Kim, and A. Abu-Siada, "Oil-Immersed Power Transformer Condition Monitoring Methodologies: A Review,” Energies, vol. 15, no. 9, p. 3379, 2022. DOI: 10.3390/en15093379

[13] G. J. Toman and R. W. Sohre, "Aging Management Guideline for commercial nuclear power plants: Power and distribution transformers," Sandia National Labs., Tech. Rep. SAND-93-7068, 1994.

[14] R. Janura, M. Toman, and P. Trnka, "Analysis of distribution transformer insulation using domain method," in Proc. IEEE ELEKTRO, 2014, pp. 632–636. DOI: 10.1109/ELEKTRO.2014.6848905

[15] Y. Huang et al., "Insulation resistance and safety in hybrid electric appliances,” International Journal of Electrical Safety, vol. 48, no. 6, pp. 337–349, 2022.

[16] H. Robinson and L. Green, "Eco-friendly insulation materials for hybrid electric appliances,” Environmental Science and Technology, vol. 52, no. 7, pp. 482–495, 2021.

[17] G. J. Toman and R. W. Sohre, "Aging Management Guideline Power and distribution transformers," Sandia National Labs., Tech. Rep. SAND-93-7068, 1994. DOI: 10.2172/10154007

[18] E. Brown, J. Smith, and M. Wilson, "Insulation resistance measurements for machine insulation," in Proc. IEEE Electrical Insulation Conf. (EIC) , 2011, pp. 342–346. DOI: 10.1109/EIC.2011.5996158

[19] D. P. Robalino et al., "A Systematic Approach to Assess the Insulation Condition of Liquid-Immersed Transformers," in Proc. IEEE ICPADM, 2024. DOI: 10.1109/icpadm61663.2024.10750757

[20] Y. Chrismondari, R. Fauzi, and D. Saputra, "Implementasi dan Pengujian Tahanan Isolasi pada Transformator Distribusi 200 kVA,"Jurnal Indragiri Penelitian Multidisiplin , vol. 5, no. 3, 2025. DOI: 10.58707/jipm.v5i3.1299

[21] IEEE Standards Association, "IEEE Guide for Diagnostic Field Testing of Electric Power Apparatus Part 1," IEEE Std C57.152-2013, 2013.

[22] A. Smith and M. Johnson, "Principles of insulation resistance testing,” Electrical Systems Review, vol. 28, no. 2, pp. 104–112, 2020.

[23] W. Hauschild and E. Lemke, "High-Voltage Testing on Site," in High-Voltage Test and Measuring Techniques, Springer, 2014.

[24] T. Williams, "Principles of insulation resistance in electrical systems,” International Journal of Electrical Engineering, vol. 44, no. 1, pp. 57–68, 2019.

[25] L. Jin, D. Kim, and A. Abu-Siada, "Oil-Immersed Power Transformer Condition Monitoring Methodologies: A Review,” Energies, vol. 15, no. 9, p. 3379, 2022.

[26] R. Janura, M. Toman, and P. Trnka, "Analysis of distribution transformer insulation using domain method," in Proc. IEEE ELEKTRO, 2014, pp. 632–636.

[27] J. Harris, "Improving insulation resistance in high-voltage systems," Journal of Electrical Power Systems, vol. 59, no. 3, pp. 109–120, 2021.

[28] S. Thungsuk, K. Sripakagorn, and C. Rattanapan, "The Characterization Analysis of the Oil-Immersed Transformers,” Applied Sciences, vol. 12, no. 8, p. 3970, 2022. DOI: 10.3390/app12083970

[29] X. Liang, "Electrical Test and Relay Protection Analysis of Power Transformer,” International Journal of Electrical Power and Energy Systems, vol. 2, no. 1, 2024. DOI: 10.62051/ijepes.v2n1.07

[30] M. Mustafa, A. Priyadi, and M. Pujiantara, "The through fault current effect of 150/20 kV transformer to its insulation resistance and Tan Delta test," in Proc. IEEE ICHVEPS , 2017, pp. 390–394. DOI: 10.1109/ICHVEPS.2017.8225941

@article{1718860,
      author = {Johnson Gbadebo Adenle, Opakunle James Akinpelu, Oluwole Oladele Obanisola},
      title = {Data-Driven Condition Assessment and Remaining Life Prediction of Low-Voltage Distribution Transformers Using Insulation Resistance Measurements: A Case Study of Ajayi Crowther University Distribution Network},
      journal = {Iconic Research And Engineering Journals},
      year = {2026},
      volume = {9},
      number = {12},
      pages = {1886-1896},
      issn = {2456-8880},
      url = {https://www.irejournals.com/formatedpaper/1718860.pdf},
      abstract = {This paper presents a comprehensive insulation resistance (IR) assessment of low voltage distribution transformers at Ajayi Crowther University (ACU), Oyo, Nigeria. The study evaluates the safety, reliability, and operational efficiency of four distribution transformers (three 500 kVA units and one 750 kVA unit) through systematic IR testing using a Megger MIT1025 insulation tester. Testing was conducted in three configurations: Line-to-Earth (L-E), Neutral-to-Earth (N-E), and Line-to-Neutral (L-N), with results corrected to a standard temperature of 20°C and benchmarked against IEEE standards. Statistical analysis revealed an overall mean corrected IR of 137.5 MΩ with a standard deviation of 21.46 MΩ. Three transformers (T1, T3, and T4) demonstrated healthy insulation with corrected IR values ranging from 100 to 160 MΩ. However, transformer T2 exhibited localized insulation degradation, failing the L-N test with a corrected IR of 90 MΩ, below the IEEE minimum threshold of 100 MΩ. The findings indicate that while the university's electrical distribution system is largely in satisfactory condition, immediate corrective maintenance is required for T2.},
      keywords = {Insulation Resistance, Distribution Transformers, Megger Testing, IEEE Standards, Preventive Maintenance, Power Quality, Electrical Safety.},
      month = {June},
      doi = {https://doi.org/10.64388/IREV9I12-1718860}
  }