| Title |
Breakdown Voltage and PD Characteristics of SF_6/CF_4 Mixtures in Nonuniform Field |
| Authors |
황청호(Hwang, Cheong-Ho) ; 성허경(Sung, Heo-Gyung) ; 허창수(Huh, Chang-Su) |
| Keywords |
Breakdown ; AC Voltage ; partial discharge(PD) ; LI ; CF_4 ; SF_6 |
| Abstract |
New gas mixtures are now finding applications such as interrupting media for high-voltage circuit breakers. These mixtures consist of a high content of carbon tetrafluoride(CF_4) added to sulfur hexafluoride(SF_6). Nowdays SF_6 has been established for the use in gas insulated substations due to its high insulation withstand level and good arc quenching capability. At this paper Breakdown characteristics were investigated for SF_6/CF_4 mixtures when AC voltage and standard lightning impulse voltage(LI) was applied in a needle-plane electrodes. And partial discharge(PD) experiments were carried out in the test chamber which was made in needle-plane electrode. And φ-Q-N distribution of partial discharge signals was analyzed. The total pressure of the SF_6/CF_4 mixtures was varied within the range of 0.1-0.5 Mpa in the test chamber. The breakdown voltage in needle-plane electrode displayed N shape characteristics for increasing the content of SF_6 at positive impulse voltage and the PD inception voltage was increased slightly when pressure of SF_6/CF_4 Mixtures was increased. Maximum PD inception voltage is showed in 80% SF6/20%CF_4. |