Reliability Evaluation of Aging Nigeria Power Distribution System Using Monte Carlo Simulation

International Journal of Electrical and Electronics Engineering
© 2020 by SSRG - IJEEE Journal
Volume 7 Issue 2
Year of Publication : 2020
Authors : UchennaK. Obu, Lazarus O. Uzoechi
How to Cite?

UchennaK. Obu, Lazarus O. Uzoechi, "Reliability Evaluation of Aging Nigeria Power Distribution System Using Monte Carlo Simulation," SSRG International Journal of Electrical and Electronics Engineering, vol. 7,  no. 2, pp. 7-13, 2020. Crossref,


This paper evaluated aging and non-aging effects in the Nigerian distribution system using Monte Carlo approach. It is a known fact around the world that most customer service interruptions are caused due to failure in distribution system. This failure is mostly caused by the aging of the equipment involved. Hence, considering reliability assessments provides an opportunity to incorporate the cost or losses incurred by the utility’s customer because of power failure and this must be considered in planning and operating practices. Monte Carlo Simulation method is used in this study and it incorporates different methods used for sampling the age of the equipment. This work is limited specifically to six (6) load points of a selected 11kV feeder in Owerri distribution system network. Aging and Non-aging conditions wereanalyzed, and the reliability indices obtained. Three different methods were used to assess the distribution of failure due to aging of the distribution transformer and they are Interval by Interval Method, Time to Scale Transformation Method and Thinning Algorithm Method. They are modeled with an incremental value of the aging factor, β, of 0.075 starting from the first year with the aging factor of 1. This distribution shows how age affects equipment with increase in the number of years as designed by the bathtub curve. The results show that failure rate increases as number of years increases and the energy lost due to aging in the equipment is also increased. It is observed that after the number of years considered, that is 50 years, the energy lost is almost equal to the rating of the transformer and the unavailability of the transformer is almost one(1). Therefore, for these transformers to last longer, aging should be put into consideration and the things that limit the age of these transformers such as maintenance of the equipment, changing of transformer oil, reducing the load on the transformers or applying load shedding mechanism, etc., should be done on the transformers for longer life.


Distribution Reliability, Aging factor, Failure rate,Monte Carlo Simulation.


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