Oil Aging due to Partial Discharge Activity
2013 (English)In: Proceedings of the23rd NORDIC INSULATIONSYMPOSIUM, NORD-IS &Akademika Publishing , 2013, 85-88 p.Conference paper (Other (popular science, discussion, etc.))
Oil is the main insulation in power transformers and over long time of ageing its insulation properties can change. In this paper ageing of oil due to the exposure to electric discharges was investigated. The effect of high energy discharges (complete arc) and low energy discharges (partial discharges) on oil properties such as breakdown strength and oil conductivity was investigated. An experimental setup consisting of two spherical electrodes was designed. The adjustable distance between the two electrodes made it possible to have PD with different magnitude. The oil conductivity and breakdown strength was measured for three sets of experiments. The first group of experiments was performed on new oil in order to have a reference for comparison. In the second group of experiments the new oil samples was exposed to 1000 and 3000 lightning impulses. In the third group of experiments new oil samples was exposed to partial discharge for different duration of time. Oil conductivity and breakdown strength of these aged samples were compared with new oil. The results show that after exposure to lightning impulse oil conductivity increases and breakdown strength decreases, However PD activity for short time does not change the oil conductivity but it reduces the breakdown strength.
Place, publisher, year, edition, pages
NORD-IS &Akademika Publishing , 2013. 85-88 p.
Other Electrical Engineering, Electronic Engineering, Information Engineering
IdentifiersURN: urn:nbn:se:kth:diva-137983ISBN: 978-82-321-0274-7OAI: oai:DiVA.org:kth-137983DiVA: diva2:680051
23rd NORDIC INSULATION SYMPOSIUM,NORDI-IS13 June 9–12, 2013 Trondheim, Norway
QC 201401072013-12-172013-12-172015-02-06Bibliographically approved