Evaluating the situation and solutions to improve the efficiency of main transformer’s operation in thermal power plants

  • Vu Minh Hung
  • Le Van Sy
  • Nguyen Phan Anh
  • Nguyen Ha Trung
Keywords: Transformer, thermal power, losses, efficiency, CLET


The transformer is an important electrical equipment in power plants, converting the voltage from 20 - 26kV at the generator output to 220 - 230kV. After a period of use, it is necessary to re-evaluate losses, efficiency, and operation mode to have suitable measures to increase working efficiency and limit incidents, as well as prolong the transformer’s life. The authors conducted surveys at 5 power plants (Ca Mau 1 and 2, Nhon Trach 1 and 2, and Vung Ang). The transformers here have a capacity between 231 - 300MVA, and have been operating for 6 - 13 years. Based on measurement data, the authors have built the CLET software (Computing Losses and Efficiency of
Transformer) to analyse and evaluate the status of operation and performance results of the above machines. From there, the authors made suggestions on operation and maintenance to ensure safety and prolong the life of the machine.


[1]. R.Gouws and O.Dobzhanskyi, "Efficiency analysis of a three-phase power transformer", Energize, pp. 61 - 65, 2014.
[2]. Aleksandar Damnjanovic, "The measurement and evaluation of distribution transformer losses under non-linear loading", IEEE Power Engineering Society General Meeting, Denver CO, 9 June, 2004.
[3]. Angelo Baggini, "Power transformers - Introduction to measurement of losses", Industrial and Tertiary Product Testing and Application of Standard, 2016.
[4]. Ankit M.Patel, Aniruddha S.Jhala and Hitesh M.Karkar, "Analysis of stray losses calculation in autotransformer using coupled IEM and FEM technique", International Journal of Advance Engineering and Research Development (IJAERD), Vol. 1, No. 3, 2014.
[5]. Manmohan Singh, Madhu Verma, Anuj Kanaujia, Sakshi Rai and Anagha Soman, "Reduction of stray losses in distribution transformer using different materials of clamping", International Research Journal of Engineering and Technology (IRJET), Vol. 5, No. 5, pp. 2738 - 2740, 2018.
[6]. Juan Carlos Olivares-Galvan, Salvador Magdaleno-Adame and Rafael Escarela, "Reduction of stray losses in flange-bolt regions of large power transformer tanks", IEEE Transactions on Industrial Electronics, Vol. 6, No. 8, pp. 4455 - 4463, 2014.
[7]. Masood Moghaddami, Arif I.Sarwat and Francisco de Leon, "Reduction of stray loss in power transformers using horizontal magnetic wall shunts", IEEE Transactions on Magnetics, Vol. 53, No. 2, 2017.
[8]. Yun Zhang, "Research on hot spot temperature calculation and analysis of online, monitoring method of oil-immersed power transformer winding", Advances in Computer Science Research, 2017.
[9]. Longnv Li, Wei Liu, Hai Chen and Xiaoming Liu, "Prediction of oil flow and temperature distribution of transformer winding based on multi-field coupled approach", The Journal of Engineering, Vol. 16, pp. 2007 - 2012, 2019.
[10]. Md Mominul Islam, Gareth Lee and Sujeewa Nilendra Hettiwatte, "A review of condition monitoring techniques and diagnostic tests for lifetime estimation of power transformers", Electrical Engineering, Vol. 100, pp. 581 - 605, 2018.
[11]. Kelvinkumar Kalariya, Hardik Kannad, Dipesh Vyas and Pallav Gandhi, "A review on ageing of power transformer and insulation life assessment", Advanced Research in Electrical and Electronic Engineering, Vol. 2, No. 2, pp. 117 - 122, 2014.
How to Cite
Vu Minh Hung, Le Van Sy, Nguyen Phan Anh, & Nguyen Ha Trung. (2020). Evaluating the situation and solutions to improve the efficiency of main transformer’s operation in thermal power plants. Petrovietnam Journal, 4, 40 - 49. https://doi.org/10.25073/petrovietnam journal.v4i0.304

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