Title |
Analysis on Electrical Breakdown Characteristics of Atmospheric Air according to the Electric Field Non-uniformity |
Authors |
김건(Geon Kim) ; 김진태(Jin-Tae Kim) ; 노홍석(Hongsuk Noh) ; 윤경록(Kyungrok Yun) ; 김세현(Sehyun Kim) ; 석복렬(Bok-Yeol Seok) |
DOI |
https://doi.org/10.5370/KIEE.2021.70.11.1697 |
Keywords |
High Voltage; Lightning Impulse Voltage; AC; Atmospheric Air; Electrical Breakdown; Design Criteria; Maximum Electric Field |
Abstract |
In this study, electrical breakdown characteristics of atmospheric air under the AC and lightning Impulse(LI) voltage waveforms were investigated to settle the electrical insulation design criteria for air insulated switchgear. To investigate the electrical breakdown characteristics according to the non-uniformity of electric field, needle-plane and 4 kinds of sphere-plane electrodes were used as the tested electrode system. Through the experimental results, it was found that when positive impulse voltage is applied, it can be the weakest in terms of electrical insulation. As for the positive LI breakdown voltage, in the case of electrodes with high non-uniformity such as needle-plane electrode, it was confirmed that electrical breakdown voltage increased almost linearly with the gap length. Based on the experimental and electric field analysis results, it is found that it is desirable to establish the air insulation design/evaluation criteria as a function according to the distance in electrodes with high non-uniform electrode systems, and as a maximum electric field function in the quasi electrode systems. Moreover, maximum electric field for partial discharge (PD) inception decreased as the cross-sectional area of the electrodes facing each other increased. |