Electrical characterisation of a single creeping streamer in transformer oil

The use of capacitive probes is of great interest for determining the electrical characteristics of the creepage discharges, and should contribute to a better understanding of the streamer propagation mechanisms. The first results on space and time variation of electric potential along the quasi-rectilinear streamer indicate that the streamer is not equipotential; there is a finite potential gradient along the channel which apparently increases when going from the needle to the tip of the streamer