Monochannel propagation mechanism in transformer oil at lowbreakdown probabilities

摘要

It is found that the channel's development character in oil in thevicinity of the minimum breakdown voltage is stepped. The channel movesdiscretely with the ionization zone length concentrated at the top ofthe channel. The similarity in the discharge development processes underlow breakdown probabilities and high overvoltages shows that the steppedprocess is fundamental and inherent to the channel development in oil.Experimental data estimate the energy density for the channel unitgeneration. The results show that the main process is field ionization,while others are connected with the phase transition, channel substanceformation and hydrodynamic phenomena