The main defects and diagnostics methods of paper-, wood-, and polymer-based solid insulation used in power transformers are presented. Specific examples of pollution, sludging, moisturizing, and mechanical defects and their development during partial and arc discharges are discussed. The distribution of moisture content of cellulose insulation along the height of transformers with natural and forced oil circulation is analyzed. The danger of local wetting of solid insulation is noted. Examples of transformer failures as a result of moistening of wooden strips for attaching taps, as well as defects in epoxy insulation of low-voltage transposed conductor windings, are given.
Similar content being viewed by others
References
RD 34.45-51.300–97. Scope and Electrical Testing Standards [in Russian], Effective 1997-05-08, Department of Science and Technology of UES of Russia RJSC, Moscow (1997).
STO 34.01-23.1-001–2017. Scope and Electrical Testing Standards [in Russian], Effective 2017-05-29, PJSC “Rosseti Moscow Region,” Moscow, 2017.
V. V. Smekalov and A. P. Dolin, “The repair of power transformers with a long service life,” in: CIGRE Session. A2, 212, 8 (2004).
RF Pat. No. 2387492, A. P. Dolin, S. G. Otmorsky, and V. V. Smekalov, “Method for cleaning oil-filled power electrical equipment,” No. 2008134862H2; appl. 28.08.2008; publ. 27.10.2010.
Methodological Guidelines for Determining the Moisture Content in Solid Insulation of Windings of Power Transformers (Shunt Reactors) on the Basis of Measured Dielectric Characteristics [in Russian], Effective 21.06.2007, UES of Russia RJSC, Moscow (2007).
SO 34.46.605. Standard Operating Procedure. 110 – 1150 kV Transformers Having a capacity of 80 MV · A or Over. Overhaul Repairs [in Russian], Effective 2005-02-01, UES of Russia RJSC, Moscow (2001).
Author information
Authors and Affiliations
Corresponding author
Additional information
Translated from Élektricheskie Stantsii, No. 6, June 2022, pp. 27 – 33. DOI: https://doi.org/10.34831/EP.2022.1091.6.004
Rights and permissions
Springer Nature or its licensor (e.g. a society or other partner) holds exclusive rights to this article under a publishing agreement with the author(s) or other rightsholder(s); author self-archiving of the accepted manuscript version of this article is solely governed by the terms of such publishing agreement and applicable law.
About this article
Cite this article
Dolin, A.P., Kipriyanova, M.M. Major Defects and Diagnostics of Solid Insulation of Power Transformers. Power Technol Eng 56, 612–618 (2022). https://doi.org/10.1007/s10749-023-01561-5
Published:
Issue Date:
DOI: https://doi.org/10.1007/s10749-023-01561-5