Reliability Assessment of Medium Voltage Underground Cable Network—Saudi Arabia Jeddah Case Study
- 1 Department of Electrical and Computer Engineering, Faculty of Engineering, King Abdulaziz University, Jeddah, Saudi Arabia
- 2 Center of Research Excellence in Renewable Energy and Power Systems, Department of Electrical and Computer Engineering, King Abdulaziz University, Jeddah, Saudi Arabia
- 3 Center of Research Excellence in Renewable Energy and Power Systems, Department of Electrical and Computer Engineering, King Abdulaziz University, Jeddah, Saudi Arabia
- 4 Faculty of Engineering, King Abdulaziz University, Jeddah, Saudi Arabia
Abstract
The reliability of medium voltage (MV) underground cable networks is critical for uninterrupted electricity supply in urban environments, particularly in regions with harsh climatic conditions. This study presents a comprehensive reliability assessment of the MV underground cable network in Jeddah, Saudi Arabia, operated by the Saudi Electricity Company (SEC). A six-year dataset (2019-2024) comprising 435 validated fault records, cable infrastructure data, environmental parameters, and restoration times was analyzed using statistical modeling techniques. The methodology integrates descriptive statistics, Pearson correlation analysis, and probabilistic distribution modeling, including Gamma, Weibull, and Log-Logistic distributions. Goodness-of-fit was evaluated using the Kolmogorov-Smirnov test. Reliability indices (SAIFI, SAIDI, CAIDI) were calculated according to IEEE Std 1366-2012 and benchmarked against NRS 047-1 standards. The results reveal that equipment failures account for 60% of all incidents, with insulation failure (51%), cable joint faults (20%), and termination faults (17%) being the predominant mechanisms. Joint and termination defects collectively constitute 37% of equipment failures. The mean restoration time was 5.56 hours, approximately 79% higher than the SEC national average of 3.1 hours, and failed to meet NRS 047-1 targets for 30%, 60%, and 90% restoration milestones. Temperature exhibited a strong positive correlation with failures (r = 0.954), while load demand also showed strong correlation (r = 0.942). The worst-performing feeder (Hera-Feeder-01) recorded 5 failures in 2023 with a mean restoration time of 17.17 hours. The failure rate increased by 25% from 2019 to 2024, indicating progressive infrastructure deterioration. This study provides actionable recommendations for predictive maintenance, climate-adaptive strategies, and database integration to enhance network reliability. The findings offer practical guidance for utilities operating in environmentally demanding regions.
- Mavuso, T.B., Wessels, A. and Pretorius, J.H.C. (2015) Reliability Based Planning Methodology for Feeder Automation. 2015 IEEE PES Asia - Pacific Power and Energy Eng ineering Conference ( APPEEC ), Brisbane, 15-18 November 2015, 1-5. https://doi.org/10.1109/appeec.2015.7381032
- Zwane, K.C., Pretorius, J.H.C. and Wessels, A. (2017) Reliability Assessment for Medium Voltage Electrical Network: A Case Study within Eskom Distribution. https://ujcontent.uj.ac.za/esploro/outputs/conferencePaper/Reliability-assessment-for-medium-voltage-electrical/9910469007691
- Perović, B., Klimenta, D., Tasić, D., Raičević, N., Milovanović, M., Tomović, M., et al . (2022) Increasing the Ampacity of Underground Cable Lines by Optimising the Thermal Environment and Design Parameters for Cable Crossings. IET Generation , Transmission & Distribution , 16, 2309-2318. https://doi.org/10.1049/gtd2.12448
- Klimenta, D., Perović, B., Klimenta, J., Jevtić, M., Milovanović, M. and Krstić, I. (2018) Controlling the Thermal Environment of Underground Cable Lines Using the Pavement Surface Radiation Properties. IET Generation , Transmission & Distribut ion , 12, 2968-2976. https://doi.org/10.1049/iet-gtd.2017.1298
- Duffey, R.B. and Ha, T. (2013) The Probability and Timing of Power System Restoration. IEEE Transactions on Power Systems , 28, 3-9. https://doi.org/10.1109/tpwrs.2012.2203832
- (2005) NRS 048-2:2025, Edition 5: Electricity Supply—Quality of Service Standard. National Energy Regulator of South Africa (NERSA). https://www.nersa.org.za/file/5883
- Perović, B.D., Tasić, D.S., Klimenta, D.O., Radosavljević, J.N., Jevtić, M.D. and Milovanović, M.J. (2018) Optimising the Thermal Environment and the Ampacity of Underground Power Cables Using the Gravitational Search Algorithm. IET Generation , Transmission & Distribution , 12, 423-430. https://doi.org/10.1049/iet-gtd.2017.0954
- Shazly, J.H., Mostafa, M.A., Ibrahim, D.K. and Abo El Zahab, E.E. (2017) Thermal Analysis of High-Voltage Cables with Several Types of Arrangements and Configurations in the Presence of Harmonics. IET Generation , Transmission & Distributio n , 11, 3439-3448.
- Zhang, J.X., Wang, B., Ma, H.R., He, Y.F., Wang, H.X. and Zhang, H.Q. (2025) Reliability Evaluation Method for Underground Cables Based on Double Sequence Monte Carlo Simulation. Processes , 13, Article 505.
- Arias Velásquez, R.M. (2025) Transient Analysis of Temporary Overvoltage and Cable Faults in Underground Medium Voltage Systems. Results in Engineering , 25, Article ID: 103875. https://doi.org/10.1016/j.rineng.2024.103875