Research And Application About Differentiated Comprehensive Lighting Protection Technology Based On Strategies Combining With Clearing And Blocking

Lightning is the primary factor which perplexes the power grid running in a safeand stable situation for a long time. Just because of this, lightning EngineeringTechnology is still in exploring. Shenzhen Power Supply Bureau pays more attention toPower lightning protection and puts a lot of power to study special technology.Althoughthe line arresters and anti-lightning horizontal needles are installed on the differentgrades’line, lightning trip out rate of transmission line is still high caused by lightning.According to statistics to the situation of line trip of the Shenzhen Power Supply Bureaubetween the year of2003and2012, the lightning trip out of more than50%of the totalnumber of line tripping. Lightning protection is still severe.The strategies of lightning protection---combining clearing and blocking andcomprehensive controlling are developed in this paper. This method is made bystudying the thunderstorm situation in Shenzhen area, censuring the data of lightningtrip out rate in the past years, combining with comprehensive lightning protectiontechnologies in the present and contrasting the lightning protection differences betweenthe Shenzhen Power Supply Bureau and Hong Kong Electric Group.Much more attention is focused on the lightning protection of typical tower ofTransmission line in Shenzhen power network and the comprehensive improvementmeasures. The appropriate parameters of lightning protection are determined accordingto referring the line actual parameter and the data of lightning activities in line corridors.The purpose of this paper is to clear the principles and strategies of the line lightningprotection by synthesizing the indexes of lightning trip out rate based on calculationvalues. These calculation values are got by counting the rate of lightning shieldingfailure trip by improved electrical set model and rate of striking back trip out with themethods of practice. Beyond those, counting the lightning protection and influencingfactors of the110kV,220kV voltage of double circuit lines, four circuit lines on thesame tower and different voltage grade220/110kV four circuit lines on the sametower line, whose the rate of trip out are high, studying the height of tower, earthingresistance, ground elevation and protective angle, are contributed to the calculationvalues.