Researches On The Application Of The Technology Of Shield Line To Prevent Lightning Accidents In10kV Insulated-covered Conductors

In order to ensure the safety and reliability of the operation of the distribution, the lOkV distribution line, an important part of city power system, is now using overhead Insulation-covered Conductors. We all love the it because it is reliable, safe and economic and it is very easy to preserve. But the results of the operation and the data of experiments show that lighting-caused breaking is a big problem in using overhead insulation-covered conductors. In order to find some reasonable and effective methods to prevent the break of the lines by lightning, we have a lot of studies about lightning protection of10kV overhead insulation lines.This paper takes the lOkV distribution line of TaiZhou as the research object, and investigates the situation of the Lightning disasters when the Transmission lines are working, and collects the activity parameters of lightning in TaiZhou, and does entirety analysis of the measures to prevent the lightning and the current situation of the overhead lines. According to the situation and parameters when the10kV distribution network is working, this paper calculates the level of the over-voltage in10kV distribution network of TaiZhou with the model. This paper also calculates the various factors which affect the level of the over-voltage. Started with electromagnetic field and thermodynamics, this paper does a comprehensive analysis of the mechanism of the break of the lines because of lightning.Some analysis show that it is the resistance of the tower, the height of the wire, the level of the insulation and the forms of the insulator which have big influence on the rate of lightning flashover for insulation lines. The current caused by lightning can not move along the line because of the effect of the insulation materials, so there will be a lot of heat which will destroy the line. This is the main reason why the line breaks after it attacked by lightning.After learning the mechanism of the break, this paper comes up with a series of measures to protect the lines such as reducing the resistance of the tower, changing the insulation materials and using various of Lightning arresters. This passage brings up using the technology of induction lightning shield line to prevent lightning disasters. The using of the targeted measures can make the10kV distribution network working safely and reliably. The experiment of using the technology of induction lightning shield line to prevent lightning accidents shows that it can improve the level of resistance line and has a positive effects on preventing lighting-caused breaking.