The Transactions of The Korean Institute of Electrical Engineers (전기학회논문지)

The Korean Institute of Electrical Engineers (대한전기학회)
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Finite Element Analysis for Dielectric Liquid Discharge under Lightning Impulse Considering Two-Phase Flow

절연유체 내 2상유동을 고려한 뇌임펄스 응답 유한요소해석

  • 이호영 (경북대학교 전자전기컴퓨터학부) ;
  • 이종철 (강릉원주대학교) ;
  • 장용무 (한양대학교 퓨전전기응용연구센터) ;
  • 이세희 (경북대학교 IT대학 전기공학과)
  • Received : 2011.10.05
  • Accepted : 2011.10.19
  • Published : 2011.11.01
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Abstract

Discharge analysis technique for dielectric liquid was presented by using the Finite Element Analysis (FEA) under a lightning impulse incorporating two-phase flow phenomena which described gas and liquid phases in discharge space. Until now, the response of step voltage has been extensively explored, but that of lightning impulse voltage was rarely viewed in the literature. We, therefore, developed an analyzing technique for dielectric liquid in a tip-sphere electrode stressed by a high electric field. To capture the bubble phase, the Heaviside function was introduced mathematically and the material functions for the ionization, dissociation, recombination, and attachment were defined in liquid and bubble, respectively. By using this numerical setup, the molecular dissociation and ionization mechanisms were tested under low and high electric fields resulted from the lightning impulse voltage of 1.2/50 ${\mu}s$. To verify our numerical results, the velocity of electric field wave was measured and compared to the previous experimental results which can be viewed in many papers. Those results had good agreement with each other.

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References

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