COMPREHENSIVE DIAGNOSTIC ASSESSMENT OF A SUSPECTED FAULTY 1600KVA, 33/0.415KV TRANSFORMER AT DRUGFIELD SUBSTATION
Abstract
Power transformers are pivotal assets in electrical power networks, and their reliability is fundamental to power delivery system stability, safety, and efficiency. This paper presents a comprehensive diagnostic evaluation of a 1600-KVA, 33/0.415-kV Siemens oil-immersed distribution transformer at Drugfield Substation, Nigeria, following reports of operational anomalies. A suite of industry-standard diagnostic tests—including physical inspection, insulation resistance, winding continuity, single-phase transformation ratio, excitation, and earth resistance—was conducted. The results revealed catastrophic high-voltage winding insulation failure, significant HV winding resistance imbalance, and severe transformation ratio discrepancies. These findings indicate that advanced internal faults, including insulation breakdown, winding degradation, and probable open circuits, pose imminent operational and safety risks. This study underscores the importance of regular transformer health assessments, presents a mathematical framework for interpreting diagnostic data, and recommends immediate decommissioning or overhaul of the affected unit. The broader implications for asset management and grid reliability are discussed, with recommendations for advanced diagnostic and monitoring strategies.
Keywords:
Transformer diagnostics, insulation resistance, winding degradation, fault analysis, operational risk, asset managementDownloads
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Copyright (c) 2025 Jokojeje Rufus Akinnusimi, Adenekan Olujide A, Akinleye Temitope Grace
This work is licensed under a Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License.
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