Zhang Qiaogen1,Jia Jiangbo1,Yang Lanjun1,Masanori Hara2
(1.School of Electrical Engineering,Xi'an Jiaotong University,Xi'an 710049, China;2.Department of Electrical and Electronic Systems Engineering,Kyushu University,Fukuoka 812-8581,Japan)
Abstract:Charging behavior of a metallic conducting particle on a dielectrically coated electrode in the presence of electrical gradient force in SF6stressed by DC or AC voltage was discussed.The particle charge quantity was estimated with the aid of the particle motion onset voltage, and was coincident with the measurement result via Faraday cage.The charge quantity amounts to 30£¥¡«60£¥ of quantity with bare electrode in case of the grounded electrode coated with polgethylene terephthalate film of 100 ¦Ìm thickness. And the charging mechanism of the particle on a dielectrically coated electrode between non-parallel plane electrodes was investigated by observing light emission of partial discharge.Under DC voltage the conductive current through the dielectric coating or charged dielectric surface dominates during the charging,and the microdischarge between the particle and the coating arises remarkably under AC voltage.
Keywords:gas insulated system;metallic conducting particle;non-parallel plane electrode;electrical gradient force