Evaluation of Insulating Oil by Terahertz Time Domain Spectroscopy

테라헤르츠파 분광법에 의한 절연유 특성 평가

  • 김근주 (한국전기연구원 THz파 전문연구랩) ;
  • 전석기 (한국전기연구원 THz파 전문연구랩) ;
  • 선종호 (한국전기연구원 전력설비진단그룹) ;
  • 진윤식 (한국전기연구원 THz파 전문연구랩)
  • Published : 2006.08.01

Abstract

A new method on the evaluation of insulation oil was proposed. Terahertz time-domain spectroscopy (THz-TDS) was applied to investigate the properties of the insulating oil. For the diagnostics of oil degradation, three kinds of oils have been analyzed by THz-TDS. The degraded oil showed different optical and electrical constants compared with a new one. Generally, the power absorption coefficient, the refractive index, the dielectric constant and loss $tan{\delta}$ of the oil increase as the aging of insulating oil proceed. And the characteristics of two kind of insulation oil, 1-4 and 7-4, was compared in terahertz spectral region. Difference in refractive index and complex dielectric constant has been observed between the samples. The results of this study suggest that THz-TDS is a promising new means for evaluating degradation and identification of insulating oil.

Keywords

Terahertz Time-Domain Spectroscopy;Terahertz Wave;Insulating Oil;Refractive Index;Absorption;Dielectric Constant

References

  1. V. G. Arakelian, 'The Long Way to the Automatic Chromatographic Analysis of Gases Dissolved in Insulating Oil', IEEE electrical insulation magazine : a publication of the IEEE Electrical Insulation Society, Vol. 20, No.6, pp. 8-25, 2004 https://doi.org/10.1109/MEI.2004.1367506
  2. Kan. H., Miyamoto. T., Makino. Y., Namba. S., Hara. T., 'Absorption of C02 and CO gases and furfural in insulating oil into paper insulation in oil-immersed transformers', Electrical Insulation Conference Record of the 1994 IEEE International Symposium on, pp. 41-44, 1944 https://doi.org/10.1109/ELINSL.1994.401472
  3. Nagamune. K., Kobashi. S., Kondo. K., Rata. Y., Taniguchi. K., 'An ultrasonic evaluation for degradation Ultrasonics of insulating oil using fuzzy inference', 2003 IEEE Symposium on, pp. 893-896, 2003 https://doi.org/10.1109/ULTSYM.2003.1293543
  4. Hosier. I.L., Vaughan. A.S., Sutton. S.J., Davis. F.J., 'Chemical and physical properties of aged dodecylbenzene insulating oil' Electrical Insulation and Dielectric Phenomena, 2005, pp. 225-228, 2005 https://doi.org/10.1109/CEIDP.2005.1560662
  5. Aka-Ngnui. T., Benounis. M., Jaffrezic-Renault. N., Stevenson. I., Beroual. A., 'In situ monitoring of the degradation of insulating oil under AC voltage', Electrical Insulation and Dielectric Phenomena, 2005, pp. 253-256, 2005 https://doi.org/10.1109/CEIDP.2005.1560669
  6. Tae-In jeon and D. Grischkowsky, 'Nature of Conduction in Doped Silicon', Phys, Rev. Lett., Vol. 78, pp. 1106-1109, 1997 https://doi.org/10.1103/PhysRevLett.78.1106
  7. G. Gallot, Jiangquan Zhang, R. W. McGowan, Tae-In. Jeon, and D. Grischkowsky, 'Measurements of the THz absorption and dispersion of ZnTe and their relevance to the electro-optic detection of THz radiation', Appl, Phys. Lett., Vol. 74., pp, 3450-3452, 1999 https://doi.org/10.1063/1.124124
  8. Al-Douseri, F.M., Liu, Haibo, Jin Yun-Sik, Chen, Yunqin, Zhang, X.C, 'Applications of THz-time domain spectroscopy and far-infrared Fourier transform spectroscopy on petroleum products analysis', Infrared and Millimeter Waves, 12th International Conference on Terahertz Electronics, 2004. pp. 401-402, 2004 https://doi.org/10.1109/ICIMW.2004.1422131
  9. D. Dragoman and M. Dragoman, 'Terahertz fields and applications', Prog. Quantum Electronics, Vol. 28, pp. 1-66, 2004 https://doi.org/10.1016/S0079-6727(03)00058-2
  10. Stephen E. Ralph and D. Grischkowsky, 'Trap-enhanced electric fields in semi-insulators : The role of electrical and optical carrier injection', Appl, Phys. Lett. Vol. 59. pp. 1972-1974, 1991 https://doi.org/10.1063/1.106153
  11. 진윤식, 김근주, 손채화, 정순신, 김지현, 전석기, '광전도 안테나에 의한 광대역 테라헤르츠파의 발생특성' Trans. KIEE. Vol. 54C, pp. 286-292, 2005
  12. Q. Wu and X.-C. Zhang, 'Free-Space Electro-Optic Sampling of Terahertz Beam', Appl, Phys. Lett. Vol. 67, pp. 3523, 1995 https://doi.org/10.1063/1.114909
  13. 진윤식, 전석기, 김근주, 손채화, 정순신, 'ZnTe결정을 이용한 테라헤르츠파의 발생 및 검출특성' 한국광학회지, 제16권 제6호, pp. 553-599, 2005 https://doi.org/10.3807/KJOP.2005.16.6.553
  14. S.P.Mickan and X.-C. Zhang, 'T-Ray Sensing and Imaging', Int'l J. High Speed Electronics and systems, Vol. 13, pp. 601-676, 2003 https://doi.org/10.1142/S0129156403001843
  15. 講談社 サイエンティフィク, '電氣絶緣油ハンドブック石油學會/編' Chapter 1, 1989