TY - JOUR AU - Abderrahmane Settaouti PY - 2019/09/30 Y2 - 2024/03/28 TI - Impulse Breakdown Characteristics of Main Gap in the Presence of a Local Discharge JF - Journal of Applied Science & Process Engineering JA - J. Appl. Sci. Process Eng. VL - 6 IS - 2 SE - Articles DO - 10.33736/jaspe.983.2019 UR - https://publisher.unimas.my/ojs/index.php/JASPE/article/view/983 AB - The characteristics of impulse breakdown voltages and the influence of the position of third electrode in air gap are investigated experimentally to study the parameters influencing the breakdown voltage in the presence of metallic objects around the high voltage power apparatus with air insulation. Experimental results show that the factors affecting the breakdown voltage are the shape and the size of the grounded electrode, the third metallic electrode location and the gap length. A comparison between negative and positive polarities of the applied voltages indicates an important influence of the polarity in the dielectric breakdown mechanism. The possible mechanism by which the local electric discharge initiates the main dielectric breakdown seems to be the high electric field around the local discharge channel and the streamers protruding from its surface. ER -