Abstract
This paper presents the experimental results of physicochemical properties studies of mixtures based on mineral oil carried out in the laboratory, under thermal stress at fixed temperature with different intervals for long period. The stability study of thermal aging is an essential tool to estimate the lifetime of insulating oil and therefore for the transformer. The tests results allow to make a comparison between the different mixtures proposed and to select the best. It is shown that the degradation rate of oils represented by kinematic viscosity is changed according to ester rate under thermal stress. We can consider that mixtures are less affected than mineral oil, depending on the ester content in the mixture. Results show the strong correlation between viscosity and dissolved decay product, under thermal stress. The increase in the soluble products in the oils, generated by degradation of oil, affects the physical parameter by increasing the kinematic viscosity. These measures are the main criterion to evaluate the stability of physical parameter of oil in-service.
Similar content being viewed by others
References
Liao R, Liang S, Li J (2012) Comparison of ageing results for transformer oil-paper insulation subjected to thermal ageing in mineral oil and ageing in retardant oil. IEEE Trans Dielectr Electr Insul 19(1):225–232. https://doi.org/10.1109/TDEI.2012.6148522
Ciuriuc A, Vihacencu MS, Dumitran LM (2012) Comparative study on power transformers vegetable and mineral oil ageing. In: IEEE international conference on applied and theoretical electricity (ICATE), pp 128–133. https://doi.org/10.1109/ICATE.2012.6403401
Hochart B (1988) Le transformateur de puissance 2eme Edition, Technique et documentation, La voisier
Augusta M, Martins G, Gomes AR (2012) Comparative study of the thermal degradation of synthetic and natural esters and mineral oil: effect of oil type in the thermal degradation of insulating kraft paper. IEEE Electr Insul Mag 28(2):22–28. https://doi.org/10.1109/MEI.2012.6159178
Fofana I, Bouaîcha A, Farzaneh M, Sabau J, Bussieres D, Robertson EB (2010) Decay products in the liquid insulation of power transformers. IET Electr Power Appl 4(3):177–184. https://doi.org/10.1049/iet-epa.2009.0181
Wilhelm HM, Stocco GB, Batista SG Jr (2013) Reclaiming of in-service natural ester-based insulating fluids. IEEE Trans Dielectr Electr Insul 20(1):128–134. https://doi.org/10.1109/TDEI.2013.6451350
Fofana I, Wasserberg V, Borsi H, Gockenbach E (2006) The effect of temperature gradient on the dielectric properties of insulating fluids. In: IEEE international conference symposium on electrical insulation, pp 523–526. https://doi.org/10.1109/ELINSL.2006.1665371
Loiselle L, Fofana I, Sabau J, Magdaleno-Adame S, Olivares-Galvan JC (2015) Comparative studies of the stability of various fluids under electrical discharge and thermal stresses. IEEE Trans Dielectr Electr Insul 22(5):2491–2499. https://doi.org/10.1109/TDEI.2015.7311022
Eberhardt R, Wieser B, Lick W, Muhr HM (2011) Dissolved gas analysis investigations on ester liquids after breakdown. In: IEEE international conference on dielectric liquids, pp 1–4. https://doi.org/10.1109/ICDL.2011.6015447
Yuliastuti E (2010) Analysis of dielectric properties comparison between mineral oil and synthetic ester oil. Delft University of Technology, Delft
Spohner M, Cséfalvay G (2013) Mineral oils and methyl esters of natural oils in electrical engineering. In: Proceedings of the 19th conference STUDENT EEICT
Biçen Y, Çilliyüz Y, Aras F, Aydugan G (2011) An assessment of aging model of IEEE/IEC standards for natural and mineral oil-immersed transformer. In: IEEE international conference on dielectric liquids, pp 1–4. https://doi.org/10.1109/ICDL.2011.6015442
Boris H, Gockenbach E, Dolata B (2008) Ester fluids as alternative to mineral based transformer oil. In: IEEE international conference on dielectric liquids, pp 1–4. https://doi.org/10.1109/ICDL.2008.4622541
Berger N (2008) Liquides isolants en électrotechnique, Caractéristiques des produits. Techniques de l’ingénieur D2471-1
IEC 60422 (2003) Mineral insulating oils in electrical equipment Supervision and maintenance guidance, Edition 4.0 2003-01
ASTM Designation 1934–95 (2005) Standard test method for oxidative aging of electrical insulating petroleum oils by open-beaker method, vol. 10.03
International Standard ISO 3104 (1994) Petroleum products, opaque liquid and transparent determination of kinematic viscosity and calculation of dynamic viscosity
ASTM Designation 6802-02 (2010) Test method for determination of the relative content of dissolved decay products in mineral insulating oils by spectrophotometry, vol. 10.03
IEC 60156 VDE 0370-5 (1996) Insulating liquids—determination of the breakdown voltage at power frequency—Test method
Berger N (2002) Liquides isolants en électrotechnique, Présentation générale. Techniques de l’ingénieur D2470-1
Perrier C, Ryadi M, Bertrand Y, Tran-Duy C (2010) Comparison between mineral and ester oils. CIGRE Session, Paris
Acknowledgements
It is a pleasure to thank Pr I. Fofana, responsible of research Chair on the Aging of Power Network Infrastructure (ViAHT) at the University du Québec at Chicoutimi (Canada), for these tips and permanent orientation. I also thank my thesis director Pr D. Mahi for their permanent availability. This work was carried out at the University of Laghouat, Algeria. I would like to cordially thank Pr M. Yousfi, responsible for research Chair, for sharing his valuable knowledge and for acceptance to realize this work within the basic sciences laboratory. It is a pleasure to thank also Dr. M. Taouti, responsible for Process Engineering Laboratory.
Author information
Authors and Affiliations
Corresponding author
Additional information
Publisher’s Note
Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.
Rights and permissions
About this article
Cite this article
Hamdi, A., Mahi, D. & Boudraa, S. Study of kinematic viscosity of mixture oils under thermal aging in power transformer. Electr Eng 100, 2373–2381 (2018). https://doi.org/10.1007/s00202-018-0709-5
Received:
Accepted:
Published:
Issue Date:
DOI: https://doi.org/10.1007/s00202-018-0709-5