Investigations on PD Characteristics of Thermal aged Palm and Corn Oil for Power Transformer Insulation Applications

  • Senthilkumar, S. ;
  • Karthik, B. ;
  • Chandrasekar, S.
  • Received : 2013.10.27
  • Accepted : 2014.03.03
  • Published : 2014.09.01


Partial discharge (PD) detection plays a major role in the life time assessment of liquid insulation in power transformers. Many research works are being carried out to replace conventional mineral oil insulation in transformers by vegetable oils. It is necessary to understand the PD characteristics of vegetable oils before recommending them as an alternate for mineral oil. In this paper, the breakdown strength and PD characteristics of palm and corn oil were investigated in both unaged and thermally aged conditions. Laboratory experiments were performed as per IEC test procedures. PD signals were measured using wide band detection system. Phase resolved PD pattern of vegetable oils and mineral oil were compared. Effect of increase in voltage stress on the PD pattern of palm and corn oil were studied. Time and frequency domain analysis of PD pulses at needle-plane electrode configuration was carried out. Statistical analysis of PD pattern i.e. skewness and shape parameter variations with respect to applied thermal stress were also carried out. From the results, it is observed that palm and corn oils have better breakdown strength and PD characteristics even under long-term thermal stress and hence they can be used for power transformer applications.


Power transformer;Breakdown strength;Partial discharge;Vegetable oil;Frequency spectrum;Statistical analysis


  1. E.Kuffel and W.S. Zaengl, "High Voltage Engineering Fundamentals", Pergamon Press, Oxford, New York, 1984.
  2. J. Li, Z. Zhang, P. Zou, S. Grzybowski, and M. Zahn, "Preparation of a Vegetable Oil-based Nanofluid and Investigation of Its Breakdown and Dielectric Properties", IEEE Electr. Insul. Mag., vol. 28, no. 5, pp. 43-50, 2012.
  3. Suwarno M. Ilyas, "Study on the Characteristics of Jatropha and Ricinnus Seed Oils as Liquid Insulating Materials", in Proceedings of the Annual Report Conference on IEEE Electrical Insulation and Dielectric Phenomena, pp.162-166, 2006.
  4. Martin, N. Lelekakis, W. Guo, and Y. Odarenko, "Further Studies of a Vegetable-Oil-Filled Power Transformer", IEEE Electr. Insul. Mag., vol. 27, no. 5, pp. 6-13, 2011.
  5. V.Arun and S.Chandrasekar, "Study on electrical and thermal characteristics of biodegradable vegetable oils for power transformer applications", in Proceedings of the International conference on electrical energy systems and power electronics in emerging economies, ICEESPEEE'09, SRM University, Chennai, pp.1012-1016, 16-17 Apr 2009.
  6. U.U. Abdullahi, S.M. Bashi, Robia Yunus, Mohibullah and Hj. An1ir Nurdin, "The Potentials of Palm Oil as a Dielectric Fluid", in Proc. of National Power & Energy Conference (PECon), pp. 224-228, Kuala Lumpur, Malaysia, 2004.
  7. Suwarno Aditama, "Dielectric properties of Palm oils as liquid insulating materials: effects of fat content", in Proc. of International symposium on electrical insulating materials, pp. 91-94, Japan, June 2005.
  8. L. Hosier, A. Guushaa, E.W. Westenbrink, C. Rogers, A. S. Vaughan, and S. G. Swingler, "Aging of Biodegradable Oils and Assessment of Their Suitability for High Voltage Applications", IEEE Trans. Dielectr. Electr. Insul., vol. 18, no. 3, pp. 728-738, 2011.
  9. B. S. H. M. S. Y. Matharage, M. A. R. M. Fernando, M.A.A.P. Bandara, G.A.Jayantha and C.S.Kalpage, "Performance of Coconut Oil as an Alternative Transformer Liquid Insulation", IEEE Trans. Dielectr. Electr. Insul., vol. 20, no. 3, pp. 887-898, 2013.
  10. J.I. Jeong, Jung-SikAn and C.S. Huh, "Accelerated Aging Effects of Mineral and Vegetable Transformer Oils on Medium Voltage Power Transformers", IEEE Trans. Dielectr. Electr. Insul., vol.19, no.1, pp.156-161, 2012.
  11. Stefan Tenbohlen and Maik Koch, "Aging Performance and Moisture Solubility of Vegetable Oils for Power Transformers", IEEE Trans. Power Delivery, vol.25, no.2, pp.825-830, 2010.
  12. M.H. Abderrazzaq and F. Hijazi, "Impact of Multifiltration Process on the Properties of Olive Oil as a Liquid Dielectric", IEEE Trans. Dielectr. Electr. Insul., vol. 19, no. 5, pp. 1637-1680, 2012.
  13. G.K.Frimpong, T.V.Oommen and R.Asano, "A Survey of Aging Characteristics of Cellulose Insulation in Natural Ester and Mineral Oil", IEEE Electr. Insul. Mag., vol. 27, no. 5, pp. 36-48, 2011.
  14. D. Martin and Z.D. Wang, "Statistical Analysis of the AC Breakdown Voltages of Ester Based Transformer Oils", IEEE Trans. Dielectr. Electr. Insul., vol. 15, no. 4, pp. 1044-1050, 2008.
  15. Cavallini, M. Conti, A. Contin and G.C. Montanari, "Advanced PD Inference in On-Field Measurements. Part.2: Identification of Defects in Solid insulation Systems", IEEE Trans. Dielectr. Electr. Insul., vol. 10, pp. 528-538, 2003.
  16. Contin, A. Cavallini, G.C. Montanari, G. Pasini and F. Puletti, "Digital detection and fuzzy classification of partial discharge signals", IEEE Trans. Dielectr. Electr. Insul., vol. 9, pp. 335-348, 2002.
  17. Andrea Cavallini, S.Chandrasekar and Gian Carlo Montanari, "Inferring Ceramic Insulator Pollution by an Innovative Approach Resorting to PD Detection", IEEE Trans. Dielectr. Electr. Insul., vol. 14, no. 1, pp. 23-29, Feb 2007.
  18. Andrea Cavallini, A. Contin, Gian Carlo Montanari, and F. Puletti, "Advanced PD inference in on-field measurements. Part I. Noise rejection", IEEE Trans. Dielectr. Electr. Insul., vol. 10, pp. 216-224, 2003.
  19. M. Pompili, "Partial discharge development and detection in dielectric liquid", IEEE Trans. Dielectr. Electr. Insul., vol. 16, no. 6, pp. 1648-1654, 2009.
  20. D. Imamovic, K.X. Lai, N.A. Muhamad, B.T. Phung and T.R. Blackburn, "Partial Discharge and Dissolved Gas Analysis in Bio-Degradable Transformer Oil", in Proc. of Cigre 16, pp. 1-7, Brugge 2007.
  21. Zhongdong Wang, Xin Wang, Xiao Yi and Sitao Li, "Gas Generation in Natural Ester and Mineral Oil Under Partial Discharge and Sparking Faults", IEEE Electrical Insulation Magazine, vol. 29, no. 5, pp. 62-70,2013.
  22. W. G. Ariastina, B. T. Phung and T. R. Blackburn, "Measurement of partial discharges in vegetable oilimpregnated insulating system", in Proc. of TENCON IEEE Region 10 Conference, pp. 954-958, 2011.

Cited by

  1. Determination of antioxidants in vegetable insulating oils by HPLC vol.8, pp.3, 2016,
  2. Ageing Study of Palm Oil and Coconut Oil in the Presence of Insulation Paper for Transformers Application vol.11, pp.4, 2018,
  3. Physiochemical and Electrical Properties of Refined, Bleached and Deodorized Palm Oil under High Temperature Ageing for Application in Transformers vol.11, pp.6, 2018,
  4. Statistical Analysis of Partial Discharge, Lightning Impulse and BDV Characteristics of Nano SiO2-Corn Oil for HV Insulation Applications vol.14, pp.2, 2019,