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Effect of ageing in transformer oil using UV-visible spectrophotometeric technique

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In power systems, varieties of insulation materials are used to protect the high voltage power apparatus such as transformer, switchgear, current transformer, potential transformer etc. One of the most common liquid insulating materials used as a dielectric medium in transformers is the transformer oil. The transformer oil is degraded due to the combination of the ageing processes such as partial discharge (PDs), electrical arcing, and thermal ageing while it is under operation during its long period of service. In this work, the effects of different ageing processes on the optical absorption properties of insulating oil of a model transformer is studied using a UV-visible spectrophotometer diagnostic method which is presently becoming a popular method to identify the ageing of the insulating oil of high voltage transformers. It is found that the aged transformer oils exhibit optical absorption in 200–400 nm wavelength regions. The optical quality of the transformer oil is mostly degraded due to PDs, and sharp and prominent absorption peaks appear at 293 nm, 306 nm, and 324 nm wavelengths, for sample which is aged due to PDs. For other aged samples, the peak at 306 nm is absent and the optical absorption characteristics are almost similar to that of the new transformer oil.

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  1. N.A. Muhamad, B.T. Phung, T.R. Blackburn, Dissolved gas analysis (DGA) of partial discharge fault in bio-degradable transformer insulation oil, in Australasian Universities Power Engineering Conference AUPEC 2007, (Australia, 2007), pp. 1–6

  2. K.F. Thang, R.K. Aggarwal, A.J. McGrail, D.G. Esp, Analysis of power transformer dissolved gas using the self-organizing map. IEEE Trans. Power Deliv. 18, 1241–1248 (2003)

    Article  Google Scholar 

  3. IEC Standard 60270, High voltage testing: partial discharge measurement, (1996)

  4. S. O’Keeffe, C. Fitzpatrick, E. Lewis, An optical fibre based ultra violet and visible absorption spectroscopy system for ozone concentration monitoring. J. Sens. Actuat. B Elsevier 125, 372–378 (2007)

    Article  Google Scholar 

  5. S. Karmakar, N.K. Roy, P. Kumbhakar, Detection of partial discharges in a high voltage equipment. J. Electr. Eng. 9(2), 26–31 (2009)

    Google Scholar 

  6. S. Karmakar, N.K. Roy, P. Kumbhakar, Monitoring of high voltage power transformer using direct optical partial discharges detection technique. J. Opt. 38(4), 207–215 (2009)

    Article  Google Scholar 

  7. A. Sierota, J. Rungis, Electrical insulating oils Part-I: characterization and pre-treatment of new transformer oil. IEEE Electr. Insul. Mag. 11, 8–20 (1995)

    Article  Google Scholar 

  8. A. Harlin, M.G. Danikas, P. Hyvönen, Polyolefin insulation degradation in electrical field below critical inception voltages. J. Electr. Eng. 56(5–6), 135–140 (2005)

    Google Scholar 

  9. J.A. Palmer, X. Wang, A. Mander, D. Torgerson, C. Rich, Synchronous fluorescence and excitation emission characteristics of transformer oil ageing, Conference record of the 2000 IEEE International Symposium on Electrical Insulation, Anaheim, CA USA, April 2–5, (2000)

  10. X. Li, Y. Xia, L. Zahn, J. Huang, Near-cofocal activity-enhanced Raman spectroscopy for multi-trace-gas detection. Opt. Lett. 33, 2143–2145 (2008)

    Article  ADS  Google Scholar 

  11. R. J. Kisch, Using refractive index to monitor oil quality in High Voltage Transformer, Master Thesis, The University of British Columbia, Vancouver, June, (2008)

  12. M.P. Zakharich, I.I. Zaitsev, V.P. Komar, F.N. Nikonovich, M.P. Ryzhkov, I.V. Skornyakov, Analysis of transformer oil using IR Analysis. J. Appl. Spectrosc. 68, 61–65 (2001)

    Article  Google Scholar 

  13. R. Blue, D.G. Uttamchandani, O. Farish, A novel optical sensor for the measurement of Furfuraldehyde in transformer oil. IEEE Trans. Instrum. Meas. 47, 964–966 (1998)

    Article  Google Scholar 

  14. A. Abu-Siada, P. Lai Sin, S. Islam, Remnant life estimation of power transformer using Oil UV-vis spectral response, IEEE conference (2009)

  15. J. Li, W. Si, X. Yao, Y. Li, Partial discharge characteristics over differently aged oil/ pressboard interface. IEEE Trans. Dielectr.Electr. Insul 16, 1640–11647 (2009)

    Article  Google Scholar 

  16. M. Benounis, T. Aka-Ngnui, N. Jaffrezic, J.P. Dutasta, NIR and optical fiber sensor for gases detection produced by transformation oil degradation. J. Sens. Actuat. B Elsevier 141, 76–83 (2008)

    Google Scholar 

  17. T.K. Saha, Review of modern diagnostic techniques for assessing insulation condition in aged transformers. IEEE Trans. Dielectr. Electr. Insul. 10(5), 903–917 (2003)

    Article  MathSciNet  Google Scholar 

  18. I.Y. Megahed, A.A. Zaky, Influence of temperature and pressure on conduction currents in transformer oil. IEEE Trans. Electr. Insul EI-4(4), 99–103 (1969)

    Article  Google Scholar 

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Authors are grateful to MHRD, Govt. of India, for the partial financial support of the project. SK is especially grateful to MHRD, Govt. of India for the maintenance scholarship.

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Correspondence to Pathik Kumbhakar.

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Karmakar, S., Roy, N.K. & Kumbhakar, P. Effect of ageing in transformer oil using UV-visible spectrophotometeric technique. J Opt 40, 33–38 (2011).

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