(Dielectric Characteristics of SF6 and Dry-Air Gases under Lightning Impulse Voltage) 이 봉*․유양우․김동규․이복희**

6 의 대체가 스 성 능 평가 에 유용 한 정보 가 될 것이다. This paper describes dielectric characteristics of SF 6 and dry-air gases under lightning impulse voltages in a quasi-uniform electric field. In order to simulate to a quasi-uniform electric field, electric field utilization factor of the used sphere-plane electrode is 71[%]. The gas pressure of SF 6 ranges from 0.1 to 0.2[MPa] and that of dry-air ranges from 0.2 to 0.6[MPa]. Electrical breakdown voltages of SF 6 and dry-air gases are measured and analyzed as functions of the polarity of lightning impulse voltage and gas pressure. As a result, the electrical breakdown voltage of both gases under th