Researches On The Application Of Lightning Protection Performance For 10kV Insulated-covered Conductors In Jiangbei

The 10kV distribution line of city is an important part of power system To keep the distribution network runing safe and reliable is the aim of the power workers. Overhead insulation-covered conductors becoming more and more popular for ist safe, reliable, economic ,easy to maintain and so on. The 10kV distribution lines of city is realizing insulation stage by stage, but the results of research and the experience of running are reflected that overhead insulation-covered conductors easily break by lightning. Therefore,it is urgent need to research the lightning performance of 10kV distribution lines and bring up the lightning-proof mearsures of economic and reasonable.In this paper, to study the 10kVdistribution lines of Jiangbei Chongqing. To analyze the lightning situation of the 10kV distribution network of Jiangbei completely on tht basis of the practical lightning situation of the 10kV distribution network and the typical examples and the parameters of lightning which was taken by LLS. Based on the parameters of the 10kV distribution network ,established the simulation model of lightning over-voltage of the 10kV distribution lines by ATP-EMTP to study the lightning over-voltage level of the 10kV overhead insulation-covered conductors and to analyze the fators which impact the lightning-withstand level, and analized the mechanism of the breaking of the 10kV overhead insulation-covered conductors completely on the basis of the calculation of the level of short-circuit current.The results show that the fators such as tower grounding resistance, a high wire, insulation level of line, type of insulator etc, which influence the number of flashover of insulation greatly and the current after lightning disconnected by the insulation of the line and burning on the point of breakdown of the lines to produce a large amount of heat to fuse the line is the mainly reason of the lightning-caused breaking.After the analysis and the research, based on the situation of the 10kV distribution network, to bring up some measures such as reducing the tower grounding resistance, enhancing the insulation level of lines, using the arrester and so on, to reduce the rate of lightning flashover and to compare a variety measures which using both houme and abroad on the basis of the mechanism of lightning-caused breaking to bring up to set up the arc-protection hardware with post insulator on the straight-line towers to prevent lightning accidents. The application of these targeted, economy, reasonable lightning protection measures could increase the lightning-withstand level of the lines to keep the 10kV distribution network runing safe and reliable. After following up the effect of the arc-protection hardware with post insulator for one year,the resultes show that the arc-protecion hardware with post insulator could increase the lightning-withstand level of the 10kV overhead insulation-covered conductors to prevent lightning-caused breaking.