Analysis of treeing phenomena by measurement single pulse

This research is performed to analyze the treeing phenomena by measuring the discharge magnitude and discharge luminescence of single pulse. The purpose of the research is to apply this analysis to the diagnosis of degradation by electrical treeing. Treeing experiments are conducted using a PMMA block which has a needle shape void on the tip of needle electrode. One cycle of the ac applied voltage was divided into twenty equal phase angle sections, labeled φ₁, φ₂...φ₂₀ in order from one negative peak to the next negative peak of the applied voltage. The ac voltage of 14 KV is applied to the needle electrode. In this report, the discharge pulse and the image of discharge luminescence at φ₇ and φ₉ in positive and φ₁₇ and φ₁₉ in negative area are measured at the same time. As a result, discharge luminescence of single pulse branched in tree channel. Branch number and discharge magnitude were almost proportional to single pulse. Discharge luminescence often branched in φ₇, φ₉ , φ₁₇ and φ₁₉. Most of discharge luminescence in this area reached the tip of tree channel. Therefore, partial discharge in φ₇, φ₉, φ₁₇ and φ₁₉ influences tree growth