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Thermal properties of natural ester and low viscosity natural ester in the aspect of the reliable operation of the transformer cooling system
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Institute of Electric Power Engineering Poznan University of Technology ul. Piotrowo 3A, 60-965 Poznan, Poland
Institute of Chemical Technology and Engineering Poznan University of Technology ul. Berdychowo 4, 60-965 Poznan, Poland
Publication date: 2019-09-30
Eksploatacja i Niezawodność – Maintenance and Reliability 2019;21(3):384–391
The paper presents the results of comparative studies of thermal properties of various types of natural esters used as electroinsulating liquids in transformers. Adequate thermal properties of electro-insulating liquids ensure reliable work of transformers. Two natural esters were selected for the study – one commonly used in distribution transformers, the other characterized by low viscosity. Fourier Transform Infrared Spectroscopy and UV-Visible spectroscopy were used to examine the chemical structure of the examined esters. Properties such as thermal conductivity coefficient λ, kinematic viscosity υ, specific heat cp, density ρ, and thermal expansion coefficient β were analyzed. Heat transfer factor α of the liquid was calculated on the basis of obtained properties. This factor defines the ability of an insulating liquid to heat transport in the transformer, thus determining its reliability. The authors put forward a thesis that a low viscosity natural ester will have a higher heat transfer factor α due to its low viscosity, which affects the factor α. The analysis of thermal properties was carried out for the following temperatures: 25, 40, 60, and 80°C. On the basis of the calculated factor α, the temperature drops in the transformer filled with the analyzed types of natural esters were determined. It has been shown that if a low viscosity natural ester is used in the cooling system of the transformer, the temperature of the hot-spot will be lower. This fact may contribute to more reliable work of transformers and extend its service life.
Ariffin M M, Ishak M T, Hamid M H A, Katim N I A, Ishak A M, Azis N. Ageing effect of vegetable oils impregnated paper in transformer application. In proc of: IEEE International Conference on High Voltage Engineering and Power Systems 2017,
ASTM D 1903-96, Standard test method for coefficient of thermal expansion of electrical insulating liquids of petroleum origin, and askarels, 1996.
ASTM D 2766-95, Standard test method for specific heat of liquids and solids, 1995.
Aubin J, Langhame Y. Effect of oil viscosity on transformer loading capability at low ambient temperatures. IEEE Transactions on Power Delivery 1992; 7(2): 516-524,
Balzer G, Heil F, Kirchesch P, Drecher D, Meister R, Neumann C. Evaluation of failure data of HV Circiut-brakers. Cigre paper A3-305, Cigre Session Paris 2004.
Bartley W H. Analysis of transformer failures. In proc of: 36th Conference of the International Association of Engineering Insurers 2003.
Cheng L, Yu T, Wang G, Yang B, Zhou L. Hot spot temperature and grey target theory-based dynamic modelling for reliability assessment of transformer oil-paper insulation systems: a practical case study. Energies 2018; 11(1): 1-26,
Cigre Brochure 436, Experience in service with new insulating liquids, 2010.
Cigre Brochure 537, Guide for transformer fire safety practices, 2013.
Ciuriuc A, Vihacencu M S, Dumitran L M. Comparative study on power transformers vegetable and mineral oil ageing. In proc of: International Conference on Applied and Theoretical Electricity 2012,
Dombek G, Gielniak J, Wroblewski R. Fire safety and electrical properties of mineral oil/synthetic ester mixtures. In proc of: IEEE International Symposium on Electrical Insulating Materials 2017,
Dombek G, Nadolny Z. Liquid kind, temperature, moisture, and ageing as an operating parameters conditioning reliability of transformer cooling system. Eksploatacja i Niezawodnosc – Maintenance and Reliability 2016; 18(3): 413–417,
Dombek G, Nadolny Z. Thermal properties of mixture of synthetic and natural esters in terms of their applications in high voltage power transformers. Eksploatacja i Niezawodnosc – Maintenance and Reliability 2017; 19(1): 62–67,
Dombek G, Nadolny Z, Przybylek P. Investigation of parameters which have the influence on the ability of heat transport of electro-insulating liquids. Przeglad Elektrotechniczny 2014; 10: 148-151.
Fofana I. 50 years in the development of insulating liquids. IEEE Electrical Insulation Magazine 2013; 29(5): 13-25,
Girgis R, Bernsjo M, Frimpong G K. Detailed performance of a 50 MVA transformer filled with a natural ester oil versus mineral oil. Cigre paper A2-107, Cigre Session Paris 2010.
Gomez N A, Abonia R, Cadavid H, Vargas I H. Chemical and spectroscopic characterization of a vegetable oil used as dielectric coolant in distribution transformers. Journal of the Brazilian Chemical Society 2011; 22(12): 2292-2303,
IEC 60076-7, Power transformers – Part 7: Loading Guide for oil-immersed power transformers, 2005.
IEEE Power & Energy Society, IEEE Guide for acceptance and maintenance of natural ester fluids in transformers, 2008.
ISO 3104:1994, Petroleum products – Transparent and opaque liquids – Determination of kinematic viscosity and calculation of dynamic viscosity, 1994.
ISO 3675:1998, Crude petroleum and liquid petroleum products – Laboratory determination of density – Hydrometer method, 1998.
Kachler A J, Hohlein I. Aging of cellulose at transformer service temperatures. Part 1: Influence of type of oil and air on the degree of polymerization of pressboard, dissolved gases, and furanic compounds in oil. IEEE Electrical Insulation Magazine 2005; 21(2): 15-21,
Li J, Yao S H, Du B, Yao W. Analysis to principle problems and future prospect of research on vegetable insulating oils and their applications. High Voltage Engineering 2015; 41(2): 353-363,
Liao R, Guo C, Wang K, Yang L. Investigation on thermal aging characteristics of vegetable oil-paper insulation with flowing dry air. IEEE Transactions on Dielectrics and Electrical Insulation 2013; 20(5): 1649-1658,
Lopatkiewicz R, Nadolny Z, Przybylek P, Sikorski W. The influence of chosen parameters on thermal conductivity of windings insulation describing temperature distribution in transformer. Przeglad Elektrotechniczny 2012; 88(11): 126-129.
Martin D, Marks J, Saha T. Survey of Australian power transformer failures and retirements. IEEE Electrical Insulation Magazine 2017;33(5): 16-22,
McShane C P, Rapp K J, Corkran J L, Gauger G A, Luksich J. Aging of paper insulation in natural ester dielectric fluid. In proc of: IEEE Transmission and Distribution Conference and Exposition 2001,
Mehta D M, Kundu P, Chowdhury A, Lakhiani V K, Jhala A S. A review on critical evaluation of natural ester vis-a-vis mineral oil insulating liquid for use in transformers: Part 1. IEEE Transactions on Dielectrics and Electrical Insulation 2016; 23(2): 873-880,
Mehta D M, Kundu P, Chowdhury A, Lakhiani V K, Jhala A S. A review on critical evaluation of natural ester vis-a-vis mineral oil insulating liquid for use in transformers: Part II. IEEE Transactions on Dielectrics and Electrical Insulation 2016; 23(3): 1705-1712,
Mentlik V, Trnka P, Homak J, Totzauer P. Development of a biodegradable electro-insulating liquid and its subsequent modification by nanoparticles. Energies 2018; 11(3): 1-16,
Mohamad N A, Azis N, Jasni J, Ab Kadir M Z A, Yunus R, Yaakub Z. Physiochemical and electrical properties of refined, bleached and deodorized palm oil under high temperature ageing for application in transformers. Energies 2018; 11(6): 1-13,
Nadolny Z, Dombek G, Przybylek P, Przadka D. Thermal properties of mineral oil admixed with C60 and TiO2 nanoparticles. In proc of: IEEE Conference on Electrical Insulation and Dielectric Phenomena 2016,
Oommen T V. Vegetable oils for liquid-filled transformers. IEEE Electrical Insulation Magazine 2002; 18(1): 6-11,
Poiana M A, Alexa E, Munteanu M F, Gligor R, Moigradean D, Mateescu C. Use of ATR-FTIR spectroscopy to detect the changes in extra virgin olive by adulteration with soybean oil and high temperature heat treatment. Open Chemistry 2015; 13(1): 689-698,
Pompili M, Calcara L, Sturchio A, Catanzaro F. Natural esters distribution transformers: A solution for environmental and fire risk prevention. In proc of: IEEE International Annual Conference 2017,
Przybyłek P, Gielniak J. Concentration analysis of gases formed in mineral oil, natural ester, and synthetic ester by discharges of high energy. Eksploatacja i Niezawodnosc – Maintenance and Reliability 2018; 20(3): 435–442,
Radakovic Z R, Sorgic M S. Basic of detailed thermal-hydraulic model for thermal design of oil power transformers. IEEE Transaction on Power Delivery 2010; 25(2): 790-802,
Rafiq M, Lv Y Z, Zhou Y, Ma K B, Wang W, Li C R, Wang Q. Use of vegetable oils as transformer oils – a review. Renewable and Sustainable Energy Reviews 2015; 52: 308-324,
Rozga P, Stanek M, Pasternak B. Characteristics of negative streamer development in ester liquids and mineral oil in a point-to-sphere electrode system with a pressboard barrier. Energies 2018; 11(5): 1-13,
Shahsiah A, Degeneff R C, Nelson J K. A study of the temperature-based dynamic nature of characteristic gases in oil-cellulose insulation systems. IEEE Transactions on Dielectrics and Electrical Insulation 2007; 14(2): 471-479,
Shinde R. Condition monitoring of a retro-filled power transformer by natural ester Envirotemp FR3 fluid. In proc of: 3rd International Conference on Condition Assessment Techniques in Electrical Systems 2017,
Sundin D, Corkran J. A study of the relationship between insulating fluid viscosity and transformer cooling performance. In proc of: 3rd International Conference on Properties and Applications of Dielectric Materials 1991,
Szewczyk R, Vercesi G. Innovative Insulation Materials for Liquid-Immersed Transformers. DuPont Webinar 2015.
Valchos N, Skopelitis Y, Psaroudaki M, Konstantinidou V, Chatzilazarou A, Tegou E. Applications of Fourier transform-infrared spectroscopy to edible oils. Analytica Chimica Acta 2006; 573-574: 459-465,
Zhou L J, Wu G N, Yu J F, Zhang X H. Thermal overshoot analysis for hot-spot temperature rise of transformer. IEEE Transactions on Dielectrics and Electrical Insulation 2007; 14(5): 1316-1322,
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