Research On Fault Location Scheme Of 10kV Cable Network Based On Traveling Wave Principle

The structure of 10kV cable network is complex and mostly buried in the ground.Because of its small fault current and complex branch structure,the location of urban cable line has always been difficult,which has always been a major difficulty for scholars.As the main distribution network of the city,fast search and accurate location of 10kV cable line fault is closely related to the life safety of urban residents,which is also of great significance for national security and maintaining the stable operation of the society.Based on the principle of two terminal traveling wave ranging,this paper studies the location of fault points and the selection of fault sections,and carries out fault location in different levels.Through the fault section location of multi branch cable lines,the comprehensive scheme of fault location of 10kV cable lines is obtained.Firstly,the traveling wave propagation path is simulated according to the figure,and the traveling wave propagation characteristics are discussed in detail,and the positioning method is simplified according to the cable section.The structure of 10kV cable is described,and the relationship between fault location information and traveling wave time difference is explored.Finally,under the condition of combination of simulation and theory,a fault location method of multi branch cable line based on traveling wave time difference matrix algorithm is proposed.In this method,each section of the line is divided firstly,then the fault judgment matrix is constructed according to the topological structure of the line network and the traveling wave propagation path,and finally the fault point is accurately located according to the fault judgment matrix and the two terminal traveling wave positioning principle.Finally,according to the scheme of hierarchical search and step-by-step locking fault location,this paper proposes a set of fault location scheme for 10kV multi branch cable line.The 10kV cable line model of this paper is established in PSCAD simulation environment to further verify the fault location scheme of this paper.In this paper,with the help of MATLAB,the change of fault waveform is observed,the maximum value of mode is obtained when the current suddenly changes,and the arrival time of traveling wave head is accurately captured.The simulation results show that the scheme is less affected by transition resistance,fault initial phase angle and fault type,and the location accuracy is high.It can accurately locate all fault points of the line and meet the requirements of urban cable network location.Considering the difficulty of traveling wave transmission in urban cable network,this paper proposes a comprehensive fault location scheme for 10kV cable line,which has high accuracy and does not need to carry out secondary traveling wave detection.The accuracy of fault location will be further improved by optimizing the performance of the acquisition equipment of each end traveling wave.