Impulse partial discharge and breakdown characteristics of rod–plane gaps in air and N₂ gases

Abstract

SUMMARYIn response to growing environmental concerns, we attempted to develop switchgear without using SF 6 gas. In our research, we used compressed air and pure N 2 as an electrical insulation gas, because of their low global warming potential. In this paper, we examined the impulse breakdown and impulse partial discharge characteristics under various conditions related to nonuniformity of the electric field. The experimental results show that the breakdown voltage (BDV) of air is higher than that of pure N 2 gas under highly nonuniform field conditions in the rod-plane gap. On the other hand, the discharge inception voltage of air and N 2 were almost the same. Furthermore, first partial discharge (PD), leader discharge, and its transition to the breakdown were successfully observed through the measurement of discharge current and light emissions under impulse voltage application.

Clarifications on the Behavior of Alternative Gases to SF6 in Divergent Electric Field Distributions under AC Voltage

“…According to the pre-breakdown current measurements (see Figure 8) and the optical observations (see Figures 3 and 8), the negative glow streamer mode was identified as the breakdown mechanism for compressed N2. These findings agree with previous investigations [10][11][12][13][14][15]. Figure 9 summarizes the negative and the positive-inception voltage and AC breakdown measurement for 12.77% O2-87.23% CO2 at various pressures up to 10 bar abs.…”

Development of Compressed Air Insulation Technology for C-GIS

“…Then, E 50 max and PDIE of Ref. (4) are plotted in Fig. 4(a), (b), and (c) and By careful obsevation of Fig.…”

“…The breakdown characteristics of compressed air have been investigated and measured in the past (3) , and recently, breakdown voltage and partial discharge inception voltage have been measured under a few rod-to-plate gaps (4) . However, to broadly apply compressed air to C-GISs, it is important to identify dependence of breakdown on the maximum field strength on a high-voltage conductor surface (E max ).…”