TY - GEN
T1 - The character of electric charge in oil-paper insulation system-charge generation, recombination, trap formation dominated breakdown
AU - Li, Shengtao
AU - Cui, Huize
AU - Zhu, Yuanwei
N1 - Publisher Copyright:
© 2020 IEEE.
PY - 2020/7/5
Y1 - 2020/7/5
N2 - Oil-paper insulation is the main insulation material in power transformers, and its insulation performance directly determines the operating life and reliability of the transformers. The lack of understanding of the electrical characteristics of oilpaper insulation materials leads to the misunderstanding of operating condition of the transformers. Extensive studies have found that the characteristics of generation, recombination, dissipation, trap formation of electric charge in oil-paper systems are the main factors affecting their insulation properties. In this paper, thermal stress coupling by AC and DC electrical stresses are found to have significant impact on ions migration properties. Under these stresses, transformer oil molecules are decomposed into carriers that upon recombining, various gases are generated. Cellulose-based paper in oil-paper systems adsorbs electric charge to form electric double layer at the oilpaper interface. The electric double layer are physically interfacial traps in nature, which leads to the superb dielectric and breakdown characteristics of the oil-paper, especially under DC conditions. As for insulating oil, the recombination rate of ions affects the concentration of conductive ions in oil under different electric field types. Further studies are still needed to confirm the correlation between the characteristics of charges and the insulation properties of oil-paper, which is expected to improve the accuracy of transformer condition monitoring to prolong its operating life.
AB - Oil-paper insulation is the main insulation material in power transformers, and its insulation performance directly determines the operating life and reliability of the transformers. The lack of understanding of the electrical characteristics of oilpaper insulation materials leads to the misunderstanding of operating condition of the transformers. Extensive studies have found that the characteristics of generation, recombination, dissipation, trap formation of electric charge in oil-paper systems are the main factors affecting their insulation properties. In this paper, thermal stress coupling by AC and DC electrical stresses are found to have significant impact on ions migration properties. Under these stresses, transformer oil molecules are decomposed into carriers that upon recombining, various gases are generated. Cellulose-based paper in oil-paper systems adsorbs electric charge to form electric double layer at the oilpaper interface. The electric double layer are physically interfacial traps in nature, which leads to the superb dielectric and breakdown characteristics of the oil-paper, especially under DC conditions. As for insulating oil, the recombination rate of ions affects the concentration of conductive ions in oil under different electric field types. Further studies are still needed to confirm the correlation between the characteristics of charges and the insulation properties of oil-paper, which is expected to improve the accuracy of transformer condition monitoring to prolong its operating life.
UR - https://www.scopus.com/pages/publications/85101253053
U2 - 10.1109/ICD46958.2020.9342031
DO - 10.1109/ICD46958.2020.9342031
M3 - 会议稿件
AN - SCOPUS:85101253053
T3 - Proceedings of the 2020 IEEE 3rd International Conference on Dielectrics, ICD 2020
SP - 439
EP - 442
BT - Proceedings of the 2020 IEEE 3rd International Conference on Dielectrics, ICD 2020
PB - Institute of Electrical and Electronics Engineers Inc.
T2 - 3rd IEEE International Conference on Dielectrics, ICD 2020
Y2 - 5 July 2020 through 9 July 2020
ER -