Influence on Formation of Methanol and Ethanol in Oil-Filled Transformers Under Accelerated Thermal Aging

  • K. HomeierEmail author
  • M. Imani
  • T. Münster
  • T. Kinkeldey
  • P. Werle
  • D. Philipp
Conference paper
Part of the Lecture Notes in Electrical Engineering book series (LNEE, volume 598)


This contribution investigates the suitability of short-chain alcohols for estimating the condition of a cellulose insulation in power transformers. To model an accelerated thermal aging of a transformer, strips of insulation paper impregnated with different insulation liquids were kept in a glass vessel, filled with the dielectric liquid and catalyzer inclusions, in a heating chamber. After oil sampling at predefined intervals, the concentrations of furanic compounds, the degree of polymerization (DP) value and the concentrations of methanol and ethanol in the insulation liquid were measured. Three different types of insulation liquids were utilized, such as the well-known uninhibited and inhibited mineral oil as well as a new inhibited insulation liquid with different oil components, inhibitor content and manufacturing process. These insulation liquids were investigated to obtain their various aging behavior regarding the generation of 2FAL and short-chain alcohols by thermal accelerated stress.


Methanol Ethanol Thermal aging Cellulose deterioration DP value 



The authors would like to express their gratitude towards Weidmann Electrical Technology AG and GRID INSPECT GmbH for their support of this research.


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Copyright information

© Springer Nature Switzerland AG 2020

Authors and Affiliations

  • K. Homeier
    • 1
    Email author
  • M. Imani
    • 1
  • T. Münster
    • 1
  • T. Kinkeldey
    • 1
  • P. Werle
    • 1
  • D. Philipp
    • 2
  1. 1.Division of High Voltage Engineering and Asset ManagementLeibniz Universität Hannover, Institute of Electric Power Systems, Schering-InstituteHannoverGermany
  2. 2.Analysen-Service GmbH, Environmental and Oil LaboratoryLeipzigGermany

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