Copper Release Kinetics and Ageing of Insulation Paper in Oil-Immersed Transformers

Olena Sevastyanova^1,2, Bogdan Pasalskiy³, Boris Zhmud^4*

¹Departmentof Fibre and Polymer Technology, KTH—The Royal Institute of Technology, Stockholm, Sweden.
²Wallenberg Wood Science Centre, KTH—The Royal Institute of Technology, Stockholm, Sweden.
³Kyiv National University of Trade and Economics, Kyiv, Ukraine.
⁴Sveacon Consulting, Stockholm, Sweden.

DOI: 10.4236/eng.2015.78048                

Abstract

The paper provides a general overview of chemical processes leading to the degradation of oil-paper insulation in oil-immersed electrical current transformers. Previous knowledge available in literature is complemented by new results placing a specific emphasis on the physicochemical factors which affect the copper release in the insulation oil and the oil oxidation kinetics. It is demonstrated that various ageing processes interact with each other, with one or another process dominating under specific conditions. Comprehensive but disjoint studies focusing on separate sub-processes may produce rather misleading results, and occasionally, lie behind rather irrelevant quality demands imposed on the insulating liquids.

Keywords

Transformer Oil, Insulating Oil, Copper Corrosion, Paper Degradation, Ageing

Conflicts of Interest

The authors declare no conflicts of interest.

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