Electrical insulation characteristics of CO/sub 2/ and CO/sub 2/ gas mixtures under non-uniform electric field

Since SF/sub 6/ gas has been specified as one of the greenhouse gases, we attempt to develop new insulation gases or gas mixtures alternative to SF/sub 6/ gas for gas insulated switchgears (GIS). In this paper, we investigated partial discharge (PD) and breakdown (BD) characteristics of CO/sub 2/ gas and CO/sub 2/ gas mixtures as one of the promising candidates without using SF/sub 6/ gas. Experimental results revealed PD inception and BD strengths for different gas pressure and CO/sub 2/ content under lightning impulse voltage and ac high voltage application.