Measurement on the permittivity and propagation velocity of used insulation oil at UHF Band using time domain reflectometry

TDR을 이용한 극초단파 대역에서 사용 절연유의 유전율과 전파속도 측정

  • 구선근 (한전 전력연구원 전력계통연구소) ;
  • 주형준 (한전 전력연구원 전력계통연구소) ;
  • 박기준 (한국 전력공사 전력연구원 전력계통연구소) ;
  • 한기선 (한전 전력연구원 전력계통연구소) ;
  • 윤진열 (한전 전력연구원)
  • Published : 2008.11.01


We measured the permittivity and electromagnetic wave propagation velocity of used insulation oil with wide frequency range including ultra-high frequency by time domain reflectometry. The permittivity or propagation velocity is essential for locating discharge faults of oil filled power transformer. We derived 2.21 as a permittivity and $2.03{\times}10^8 m/s$ as a velocity from the measurement of pulse travelling time along a coaxial line filled with used insulation oil or air. The permittivity measurement system we designed shows high measurement accuracy and the convenience for field use.


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