Exploration And Application Of Integrated Lightning Preotection Measures For 110kV And 220kV Transmission In Fujian

Lightning disturbance is one of the leading causes of transmission line fault tripping,and has a tendency to rise year by year.On the basis of the existing blocking lightning protection idea,this thesis further research comprehensive measures to improve the lightning withstand level and reduce the rate of lightning trip.Due to the geographical features of Fujian Province,the key and difficult point of lightning protection for transmission line is the special section.So the research of the special section and the corresponding lightning protection measures are of great significance.Due to cost and technical limitations,it can not improve the lightning withstand level infinitely,lightning disturbance is virtually inevitable.So this thesis change in lightning protection thought,and then put forward the thought of grooming lightning protection and the corresponding lightning protection measures to ensure reliable operation of the equipment and no lack of power transmission.In this thesis,on the basis of the existing lightning protection research,the work in this dissertation mainly consists of following parts:(1)Through the establishment of mathematical model,calculation of lightning withstand level and application of factor decomposition method,the positive and negative factors that affect the lightning trip rate are sorted out.And then find the key point to improve the lightning withstand performance and reduce the lightning trip out rate.(2)By collecting the lightning data of transmission line in Fujian Province in recent ten years,including ground lightning density,lightning trip-out rate,lightning disturbance rate and fault category,this thesis analysis the lightning fault situation and development trend in order to provide reference for lightning protection.(3)On the basis of the existing lightning protection research,this thesis further research comprehensive measures and evaluate the practical effects,economic benefits and limitations of the lightning protection measures in order to provide reference for reasonable selection of lightning protection measures.(4)Starting from the three aspects of section characteristics,lightning protection level and data statistics,this thesis further research the lightning protection of special section and put forward the lightning protection measures for special section of transmission line,especially the research and application of line insulation.(5)This thesis analysis the shortcomings of blocking lightningprotection ideas and then put forward grooming lightning protectionidea and the application of parallel gap.The research results of this project will provide reference for lightning protection and reasonable selection of lightning protectionmeasures in the case of limited transformation costs.Due to the large number special section in Fujian province,research on measures of lightning protection measures for special section has great practical significance.And the researchon the line insulation has opened up a new direction for the lightning protection measures in the special section.The research of groominglightning protection idea and parallel gap provide snookering idea for lightning protection when the blocking measures encountered lightning proof.The research results will help to further improve the reliability of transmission lines.