RELIABILITY ASSESSMENT OF ELECTRIC POWER DISTRIBUTION: A CASE STUDY OF 2x7.5MVA, 33kV/11kV ETETE INJECTION SUB-STATION, NIGERIA.

Year 2025, Volume: 9 Issue: 2, 10 - 25, 29.06.2025

Golden Enobakhare , Emmanuel Oyonokpare

Abstract

This study aimed to assess the reliability of the 2x7.5MVA, 33kV/11kV Etete Injection Sub-Station, with a primary focus on understanding the historical performance and identifying key factors influencing its reliability. The objectives included conducting a comprehensive analysis of historical outage data, maintenance records, and operational parameters. Additionally, the study aimed to derive insights into the critical components and practices that affect substation reliability and develop recommendations for enhancing its performance. The research employed a multifaceted methodology, combining quantitative and qualitative approaches. Further, historical data, including outage records and maintenance logs, were meticulously collected and analyzed. Statistical tools, including reliability indices and time-series analysis, were employed to assess the substation's historical performance and outage patterns. Interviews with maintenance personnel and key stakeholders provided valuable qualitative insights. The study also considered external factors such as weather conditions and regulatory frameworks that influence substation reliability. Predictive modeling was used to extrapolate future scenarios, assessing the substation's ability to meet evolving demands. The study concludes that the reliability of the Etete Injection Substation varies based on observed variations in historical performance data. Over the past five years, the substation experienced an average of 9 outages annually, with an average outage duration of 3.5 hours. Outage frequencies exhibited a noticeable seasonal pattern, with an increase during the rainy season. Critical components, including transformers and circuit breakers, accounted for 70% of all outages. Furthermore, our predictive modeling revealed that without intervention, the substation may face up to 20% increase in outages in the next three years.

Keywords

Reliability , mean time to failure , downtime , availability , substation , failure rate

Ethical Statement

The authors agree that there are no conflict of interests with regards the publication of this paper

Supporting Institution

Ambrose Alli University

Project Number

1

Thanks

The authors will like to say a big thank you to the editor in chief and everyone associated with this journal for the privilege to publish in this prestigious journal..Thank you

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