Impact of different water contents on the electrical strength of oil gaps and solid/liquid interfaces in the presence of carbon particles

This paper reports on experimental investigations dealing with the impact of different water and carbon contents on the electrical strength of oil gaps without and with a solid/liquid interface in a uniform field. The results reveal that depending on the amount of carbon, the water content, and the gap distance the electrical strength of carbonized oils needs not necessarily to be lower than for clean oil under the same conditions. Moreover it will be shown that the combined impact of different carbon and water contents on the electrical strength of long oil gaps cannot in any case be deduced from results obtained at short gap spacing