Title :
Streamer and leader discharge propagation characteristics leading to breakdown in electronegative gases
Author :
Hayakawa, Naoki ; Hatta, Keiji ; Okabe, Shigemitsu ; Okubo, Hitoshi
Author_Institution :
Dept. of Electr. Eng. & Comput. Sci., Nagoya Univ.
Abstract :
This paper describes the propagation characteristics and mechanisms of partial discharge (PD) leading to breakdown (BD) in electronegative gases such as SF6/N2 and C2 F6/N2 gas mixtures for AC voltage application. An established PD measuring system of highly time-resolved PD current and light intensity waveforms, streak and light emission images enabled us to discuss the physical mechanisms of PD generation and propagation in terms of space charge behavior. Experimental results revealed that the time-resolved PD generation was divided into different groups composed of the first large PD and the subsequent small PDs; the former was identified as the leader discharge, and the latter corresponded to the streamer discharges. The successive generation of the streamer and leader discharges was interpreted by the change of critical volume size. The time-resolved PD generation characteristics leading to BD were also measured and discussed. The leader discharge would be obliged to take a detour along the periphery of the positive space charge area in the vicinity of the needle electrode, and finally result in BD in electronegative gases
Keywords :
corona; electrodes; gaseous insulation; partial discharge measurement; space charge; PD measuring system; corona stabilization effect; electrical insulation; electronegative gas mixture; leader discharge propagation; light emission image; needle electrode; partial discharge breakdown; space charge; streamer propagation; Breakdown voltage; Character generation; Charge measurement; Current measurement; Electric breakdown; Gases; Needles; Optical propagation; Partial discharges; Space charge;
Journal_Title :
Dielectrics and Electrical Insulation, IEEE Transactions on
DOI :
10.1109/TDEI.2006.1667744