Lightning Protection On 110kV Transmission Line In Zhenjiang Power Grid

With the development of society and economy,the power consumption of users increases sharply,and the scale of power system becomes larger and larger.At the same time,with the improvement of living standards of residents,the stable and reliable operation of power grid is also put forward higher requirements.Extreme weather and lightning often cause power system tripping and cause loss of production and life.And lightning stroke is more difficult to control and predict accurately than other faults,so it is necessary to do more and more detailed research on lightning protection of power system.Firstly,this paper briefly expounds the general situation of Zhenjiang power grid,describes the lightning activity and its regional distribution in detail,then selects lightning protection of transmission line as the research object,and makes statistical analysis on the data of lightning-induced tripping in Zhenjiang area in the past,and analyzes the lightning from various angles.The causes of transmission line tripping caused by strike are discussed in detail.Finally,a typical case of Zhenjiang city is selected and analyzed in combination with the field situation,and the guidance is given.Then aiming at the lightning activity and lightning trip in Zhenjiang area,the lightning protection measures are improved on the basis of conventional lightning protection measures,and the lightning protection effects before and after different lightning protection measures are analyzed by establishing a simulation tower model.Through the test and analysis of the results,it is found that the grounding resistance between the tower and the earth is reduced.Assuming that the coupling line of lightning protection,the installation of lightning rod,the arrester and the automatic closing device can improve the lightning protection effect to some extent,and different lightning protection measures are taken according to the position of the tower,the parameters of grounding resistance,the altitude and the lightning activity,and good lightning protection effect is achieved.Finally,the risk grade of transmission line is divided and the corresponding index is given.Taking Zhenjiang 110 kV transmission line as an example,the risk assessment of lightning trip-out is carried out.The factors that may cause lightning trip-out are considered separately,and their influence on lightning trip-out is analyzed.Finally,the tower of Zhenjiang 110 kV Longgao 898 transmission line is combined.Risk assessment is carried out,and corresponding improvement measures are given according to different risk levels and tower conditions.By comparing the lightning trip-out rate before and after improvement,the conclusion is drawn that the improvement measures effectively reduce the probability of lightning trip-out,which provides a reference for lightning protection research of transmission lines.