Evaluation of mineral insulating oil by rapid small scale oxidation test

##plugins.themes.academic_pro.article.main##

Ann Pamla Cruze
K. S. Lokesh

Abstract

Mineral oils are used in transformers as insulants and coolants. The long term performance of theses oils depends on their stability to oxidation of the oil. This characteristics is usually termed as resistance to oxidation process or oxidation stability. To assess oxidation stability of the insulating oils, every manufactured batch or sample is subjected to laboratory tests, by simulating the factors that influence the process of oxidation. One of the popular method followed is the oxidation stability test, where the oil is put to accelerated oxidation process by bubbling zero air over a duration of 164 to 500 hours as per IEC 61125 norms and by Rotating Pressure Vessel Oxidation Test method (RPVOT) as per ASTM D2112. Each of these procedures measure, different parameters to asses the oxidation stability of oil, depending on the test method. Experiments on same sample of insulating oils are also carried out by using a new method called Rapid Small Scale Oxidation Test method (RSSOT) ASTM D7545. The results are compared to assess the suitability of rapid small scale method for analysing the stability of insulation oils. RSSOT method has main advantage of rapid deliverance of test results and small quantity of sample. It is found that the rapid small scale method is comparable to the existing methods of oxidation stability characteristics of the oils.

##plugins.themes.academic_pro.article.details##

How to Cite
Pamla Cruze, A., & Lokesh, K. S. (2017). Evaluation of mineral insulating oil by rapid small scale oxidation test. Power Research - A Journal of CPRI, 387–394. Retrieved from https://node6473.myfcloud.com/~geosocin/CPRI/index.php/pr/article/view/92

References

  1. Russell Martin, “Experiences in service with new insulating liquids”, Cigre Publications, A235,2010.
  2. Ferguson R., Lobeiras. A. Sabou J. “Suspended particles in the liquid insulation of aging power transformers”, IEEE Electrical Insulation Magazine, Vol 18, Issue 4, pp. 17 – 23, August 2002.
  3. Mohammad R, “Aging Study and Lifetime Estimation of Transformer Mineral Oil”, American J. of Engineering and Applied Sciences, Vol 1, Issue 4, pp. 384-388, 2008.
  4. I. Fofana, A. Bouaicha, M. Farzaneh J. Sabau D. Bussieres, E.B. Robertson, “Decay products in the liquid insulation of power transformers”, IET Electr. Power Appl., Vol 4, Issue 3, pp. 177– 184, 2010.
  5. Rashmi Sanghi, “Chemistry Behind the life of a transformer”, Resonance Resonance Journal of Science Education, Vol 8, Issue 6, pp 17-23 ,2003.
  6. George A. Olah, Arpad Molnár, “Hydrocarbon Chemistry”, WILEY, Publication, ISBN 0-471-41782-3, 2003.
  7. Zhou Zhou, Feng Bing, Wan Tao, Xu Song, “Alternative method for the determination of the antioxidant content in transformer oil by electrochemical techniques”, Vol. 19, Issue: 5, pp. 1498 – 1501, 2012.
  8. I . Fofana, J.S. N’cho, J. C. OlivaresGalvan, R. Escarela-Perez, P. S. Georgilakis, “Comparative Studies of the Stabilities to Oxidation and Electrical Discharge between Ester Fluids and Transformer Oils”, pp. 14 2011.
  9. Zhou Zhou, Liu Kai, Wan Tao, Hu Xu, Qian Hui, Feng Bing, “Rapid determination of oxidation stability for transformer oils with antioxidant”, IEEE Transactions on Dielectrics and Electrical Insulation Vol. 19, Issue 5, 2012.
  10. IEC 61125, Standards for measuring of Oxidation stability, International Electro technical Commission 1992.
  11. ASTM D2112, Measurement of oxidation stability by rotating pressure vessel, American standards for testing Materials. 2001.
  12. ASTM D7545, Standard Test Method for Oxidation Stability of Middle Distillate Fuels - Rapid Small Scale Oxidation Test (RSSOT), 2014.
  13. ASTM D7525,Standard Test Method for Oxidation Stability of Spark Ignition Fuel - Rapid Small Scale Oxidation Test (RSSOT), 2014.
  14. IEC 60296, Specification for mineral insulating oils, International Electro technical Commission, 2012.
  15. IS 12463,Specification for Inhibited new mineral insulating oils. 1988-reaffirmed 2003.