Title |
Surface Discharge Mechanism of Inclined Epoxy Surface in Atmospheric Air |
Authors |
Dong-Young Lim ; Sang-Won Lee ; Seung-Wook Jee |
DOI |
http://doi.org/10.5207/JIEIE.2023.37.4.056 |
Keywords |
Electron avalanche; Flashover; Gas insulated switchgear; Spacer; Surface discharge |
Abstract |
This paper presents the surface discharge characteristics developed on an inclined epoxy surface in atmospheric air. The surface discharge experiments were conducted under AC high voltage using a rod electrode and an epoxy to measure the surface flashover voltages and surface discharge path. When the slopes of the epoxy surface were 0°, 30°, and 60°, there is little difference in the surface flashover voltages. Surface discharge developed into three cases with the changes of electrode gap (surface distance). The developments of the three discharge paths consisted of propagation from the electrode surface to the air, from the triple junction to the dielectric surface, and the electrode surface to the dielectric surface via the air. The dominant-discharge mechanisms were analyzed for the surface discharge types. A surface discharge model propagating to the epoxy surface via air were proposed based on the discharge mechanisms including the space charge effect of the positive ions. These results can be applied as basic data on electrical fire of PCB boards, coatings, and electrical equipment to which epoxy is applied. |