Study of the behavior of AC discharges of water drops on both conducting and dielectric solid surfaces

This paper presents the results of a study carried out on the deformation of a water surface and the effect water drops have on both conducting and dielectric solid surfaces subjected to a 50-Hz-volage stress. Also, contained in it are fundamental observations of current discharges characterizing water drops and metal electrode configurations as well as those configurations resulting from a flat water surface and a metal electrode. The measurements taken with both rod and point electrodes also came under investigation. The inception field strength of partial discharges between water surface and metal electrodes is analyzed. The discharge activities between water drops and between a conducting water drop and a small rod electrode on a flat hydrophobic insulator are also investigated. The results obtained characteristics of show typical discharge current during the discharge inception and development with and without water filaments, with regard to drop-drop and drop-rod configurations on the dielectric solid surface. This experimental study provides a better understanding of the processes leading up to flashover of hydrophobic insulators through discharges between water drops resulting of the distortion of these drops.