Extensions to the Finite Element Technique for the Magneto-Thermal Analysis of Aged Oil Cooled-Insulated Power Transformers

DOI: 10.4236/jemaa.2012.44022   PDF   HTML   XML   4,867 Downloads   7,721 Views   Citations


It is well known that the hot spot temperature represents the most critical parameter identifying the power rating of a transformer. This paper investigates the effect of the degradation of core magnetic properties on temperature variation of aged oil-cooled transformers. Within this work, 2D accurate assessment of time average flux density distribution in an oil insulated-cooled 25 MVA transformer has been computed using finite-element analysis taking into account ageing and stress-induced non-uniform core permeability values. Knowing the core material specific loss and winding details, local core and winding losses are converted into heat. Based upon the ambient temperature outside the transformer tank and thermal heat transfer related factors, the detailed thermal modeling and analysis have then been carried out to determine temperature distribution everywhere. Analytical details and simulation results demonstrating effects of core magnetic properties degradation on hot spot temperatures of the transformer’s components are given in the paper.

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J. Shazly and A. Adly, "Extensions to the Finite Element Technique for the Magneto-Thermal Analysis of Aged Oil Cooled-Insulated Power Transformers," Journal of Electromagnetic Analysis and Applications, Vol. 4 No. 4, 2012, pp. 167-176. doi: 10.4236/jemaa.2012.44022.

Conflicts of Interest

The authors declare no conflicts of interest.


[1] L. W. Pierce, “Hottest Spot Temperatures in Ventilated dry Type Transformers,” IEEE Transactions on Power Delivery, Vol. 9, No. 1, 1994, pp. 257-264. doi:10.1109/61.277697
[2] E. M. Eteiba, M. M. A. Aziz and J. H. Shazly, “Heat Conduction Problems in SF6 Gas Cooled-Insulated Power Transformers Solved by the Finite-Element Method,” IEEE Transactions on Power Delivery, Vol. 23, No. 3, 2008, pp. 1457-1463. doi:10.1109/TPWRD.2008.915793
[3] E. M. Eteiba, M. M. A. Aziz and J. H. Shazly, “Sensitivity of Steady-State Temperatures of SF6 Gas-Cooled-Insulated Power Transformers to Selected Parameters,” IEEE Transactions on Power Delivery, Vol. 24, No. 3, 2009, pp. 1249-1256. doi:10.1109/TPWRD.2009.2021028
[4] B. S. Guru and H. R. H?z?ro?lu, “Electromagnetic Field Theory Fundamentals,” 2nd Edition, Cambridge University Press, Cambridge, 2004.
[5] G. D. Raithby and K. G. T. Hollands, “Handbook of Heat Transfer,” 3rd Edition, McGraw-Hill Book Company, New York, 1998.
[6] M. N. Ozisik, “Heat Transfer a Basic Approach,” McGraw-Hill Book Company, New York, 1985.
[7] S. J. Salon, “Finite Element Analysis of Electrical Machines,” Kluwer Academic Publishers, Boston, 1995. doi:10.1007/978-1-4615-2349-9
[8] C. C. Hwang, “Numerical Computation of Eddy Currents Induced in Structure Steel Due to Three-Phase Current,” Electric Power Systems Research, Vol. 43, No. 2, 1997, pp. 143-148. doi:10.1016/S0378-7796(97)01177-2
[9] R. Siegel and J. R. Howell, “Thermal Radiation Heat Transfer,” McGraw-Hill Book Company, New York, 1990.
[10] A. Saleh, A. Adly, T. Fawzi, A. Omar and S. El-Debeiky, “Estimation and Minimization Techniques of Eddy Current Losses in Transformer Windings,” Proceedings of the CIGRE Conference, Paper No. 12-105, Paris, 2002.
[11] E. G. teNyenhuis, R. S. Girgis, G. F. Mechler and G. Zhou, “Calculation of Core Hot-Spot Temperature in Power and Distribution Transformers,” IEEE Transactions on Power Delivery, Vol. 17, No. 7, 2002, pp. 991-995. doi:10.1109/TPWRD.2002.803703
[12] A. A. Adly and S. K. Abd-El-Hafiz, “Utilizing Particle Swarm Optimization in the Field Computation of Non- linear Media Subject to Mechanical Stress,” Journal of Applied Physics, Vol. 105, 2009, p. 07D507.
[13] IEC 354, “Loading Guide for Oil-Immersed Power Transformers,” 2nd Edition, 1991.

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