镇宁地区110kV架空线路雷击跳闸分析及防雷策略研究OA

To mitigate the impact of lightning on power transmission from mountainous new energy stations and enhance the effectiveness of protection against lightning damage,this paper takes a 100MW photovoltaic station in Zhenning,Guizhou as a case study.It begins by analyzing the geographical and climatic conditions of the station's location,along with the spatial and temporal distribution of lightning.The study delves into the transient wave processes of lightning faults,and the mechanisms of tower lightning voltage and current,to deeply analyze the discharge mechanisms of transmission line towers due to lightning.Field investigations reveal that lightning-induced tripping of transmission lines primarily results from excessive ground resistance of towers causing backflashover voltages,and direct or induced lightning voltages exceeding the lines'lightning withstand level.Considering the main inducements of lightning trips,several lightning protection measures are implemented,including the installation of flexible grounding to reduce resistance,enhanced line insulation matching,and gapless zinc oxide surge arresters in lightning-prone sections.Field tests show a significant reduction and good maintenance of tower grounding resistance.Over the course of a year,the modified line's tripping rate is significantly lower than that of neighboring lines in the same region and the line's own historical rates during the same period.The findings demonstrate that an integrated lightning protection strategy effectively enhances the safety and reliability of transmission lines,offering significant practical value for improving the performance of lines in areas prone to frequent lightning.