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


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.


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


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