불평등 전계중에서 $SF_6$가스의 절연특성

Dielectric Characteristics of $SF_6$ Gas in Inhomogeneous Field

This paper presents dielectric characteristics of $SF_6$ gas stressed by the non-oscillating and oscillating impulse voltages in inhomogeneous fields disturbed by metallic protrusion. The propose of this investigation is to present the predischarge development and dielectric characteristics of $SF_6$ gas under VFTOs. The experiments were carried out using a needle-to-plane and two needles-to-plane gap geometries in the gas pressure ranges from 0.1 to 0.5 MPa. The gap separation was 22 mm and the needle-shaped protrusions were made of stainless steel 10 mm in length and 1.0 mm in diameter. As a result, it was found that the breakdown mechanism and predischarge current are principally dependent on applied voltage waveform and polarity.