Research On Lightning Fault Location Of 110kV Double-circuit Transmission Lines On The Same Tower

With the vigorous development of power grid construction,people's requirements for power supply reliability are also increasing.As one of the main factors for the safe operation of transmission systems,lightning strikes have always affected people's production and life.At present,40%-70% of the total number of trips in China's power system are caused by lightning strikes,which seriously threaten the safe,reliable and stable operation of China's power system.At present,our country mainly implements lightning protection measures according to the set lightning parameters.The lack of considerations for the structure of the tower and the topography and terrain cannot accurately reflect the lightning protection performance of the line.In most cases,the line arrester is also installed to protect such transmission lines.For this reason,this paper studies the lightning strike positioning method of transmission lines and locates the inconsistencies between the lightning strike points and the flashover points of the 110 kV double-circuit transmission line on the same tower.The problem has been studied in depth.At the same time,it has positive practical significance.In this paper,the fault location of the single-end method of the traditional line and the fault location of the double-end method are improved respectively,and a new lightning strike positioning method for the transmission line is established.By determining the arrival time and polarity of the initial transient current traveling wave at the monitoring point position,the source of the deflected wave and the range of the lightning strike interval are determined.The wavelet transform is used to extract the wave head time,and the corresponding lightning strike interval formula is reasonably selected for calculation and positioning.The simulation results show that the positioning error of this method is less than 0.5%,and the accuracy of ranging is improved.Compared with the improvement of single-ended method,the improvement of the double-end method is smaller and more practical.Based on the research results of this research group,the paper briefly introduces the influence of the lightning arrester action on the electromagnetic transient process of the lightning strike on the line.According to the characteristics of the lightning strike action on the lightning strike wave,the lightning strike point of the 110 kV double-circuit transmission line on the same tower Positioning analysis and research were carried out when the flashover points were inconsistent.The location and analysis of the lightning arrester caused multiple lightning arresters along the line were performed.The Hough transform method was used to process the image and the straight line calibration of the wave head.The determination,the improvement of line positioning accuracy and the study of lightning current parameter inversion and recovery have laid a certain foundation.