Publication detail

Comparative study of dielectric properties of mineral oil, synthetic ester and natural ester

SARPATAKY, M. RAJNAK, M. KURIMSKY, J. KRBAL, M. PELIKAN, L.

Original Title

Comparative study of dielectric properties of mineral oil, synthetic ester and natural ester

Type

conference paper

Language

English

Original Abstract

The current research of insulating oils for high-voltage applications focuses mainly on biodegradable oils that are in line with sustainable development. Mineral oils may in the future be replaced by more environmentally friendly materials with similar properties. One of the probable options as substitutes in the future will be synthetic or natural esters. This paper presents a comparative experimental study of mineral oil, natural ester, and synthetic ester and their dielectric properties, specifically AC breakdown voltage, lightning breakdown voltage, and thermal dependence of dissipation factor, volume resistivity, and relative permittivity. Measurements of AC and lightning breakdown voltage were performed according to IEC 60156 with a horizontally positioned sphere–sphere electrode system. Synthetic ester reached the mean value of AC breakdown voltage 60.2 kV, lightning breakdown voltage with positive polarity 144.3 kV, and with negative polarity 148.6 kV. Natural ester showed a mean value of AC breakdown voltage 58.4 kV, the lightning breakdown voltage of positive and negative polarity was 149.5 kV and 151.5 kV, respectively. Measurement of dissipation factor, volume resistivity, and relative permittivity was executed in accordance with IEC 60247 2004. The dissipation factor moved from 0.0031 at 20°C to 0.3119 at 140°C for synthetic ester and from 0.0011 at 20°C to 0.0331 at 140°C for natural ester. These results are compared with the dielectric properties of mineral oil. The challenging problem of potential oil substitution in power transformers is discussed.

Keywords

breakdown voltage; insulating oils; mineral oil; natural ester; synthetic ester

Authors

SARPATAKY, M.; RAJNAK, M.; KURIMSKY, J.; KRBAL, M.; PELIKAN, L.

Released

3. 10. 2022

Publisher

Technical University of Kosice

ISBN

9788055341040

Book

ELEKTROENERGETIKA 2022: Proceedings of the 11th International Scientific Symposium on Electrical Power Engineering

Pages from

241

Pages to

245

Pages count

5

BibTex

@inproceedings{BUT183057,
  author="Miloš {Šárpataky} and Juraj {Kurimský} and Michal {Rajňák} and Michal {Krbal} and Luděk {Pelikán}",
  title="Comparative study of dielectric properties of mineral oil, synthetic ester and natural ester",
  booktitle="ELEKTROENERGETIKA 2022: Proceedings of the 11th International Scientific Symposium on Electrical Power Engineering",
  year="2022",
  pages="241--245",
  publisher="Technical University of Kosice",
  isbn="9788055341040"
}