Analysis On Lightning Protection Level And Study On Method To Improve Lightning Protection Of 10kV Distribution Line

The 10kV distribution line is import part of distribution network, wide distribution and low insulation level. Lightning stroke trip rate occupies a fairly large proportion of all trip rate on 10 kV distribution Lines. Distribution equipments and user equipments are damaged by lightning accidents, lightning accidents cause large area blackout, even personal injury at serous situation, bring losses to industrial and agricultural production, bring inconvenience to people's life, so the current state of lightning protection should be study and find measures to improve level of lightning protection, reduce lightning trip-out rate and damage rate of distribution equipments, sure unblocked of business electrical, safety of user, safe and reliable operation of distribution network.Aim at lightning trip of 10kV distribution line, analysis that the lightning induced voltage are the main cause of flashover on distribution line. The generation mechanism of lightning induced voltages on distribution line is studied in this paper, it is pointed out that electrostatic induction component is main part of lightning induced voltage, analysis harm of lightning induced voltages. Calculation method of lightning induced voltage is given by solving electrostatic induction voltage model of overhead line. This paper introduces use of electromagnetic simulation software PSCAD/EMTDC on lightning transient Over-voltage of overhead line, analysis use of common lightning protection measures, it is pointed the important indexes on level of lightning protection are lightning withstand level and lightning trip-out rate.Combining with 10kV DONGCHENG line, use method of electromagnetic analysis,establish simulation model, analysis present level of lightning protection on line ,study factors to effect lightning withstand level and lightning trip-out rate of line, at last, according to result and Combining research results, propose measures to improve level of lightning protection on line by reducing pole and tower's height, strengthen line insulation ,reduce grounding resistance ,fix line arrester and lightning shield line ,ect.