Research On Multi-line Fault Locating Method Based On The Theory Of Travel Wave

With the rapid development of China's power industry,the scale of power grid is expanding,the structure is becoming more complex,and the length of transmission lines is increasing.This greatly increases the difficulty of line operation and management,but also increases the incidence of line faults.For a simple system,the method of two-terminal traveling wave ranging has high reliability.But when this method is applied to modern power grid,the traveling wave component has complex frequency components,fast propagation speed,and it is non-stationary signal itself,so it has strong singularity.At the same time,the complex grid structure will lead to the transmission line parameters will lead to the attenuation and distortion of different components in the traveling wave,which will make the propagation speed greatly different.These problems will lead to the selection of wave speed and the calibration of the arrival time of surge very difficult.Therefore,the traditional two-terminal traveling wave fault location method can not meet the current grid scale for accuracy and reliability testing requirements.In this paper,a fault location network is constructed,and the shortest path algorithm is used to simplify the complex multi-terminal transmission network.The method of data weighted fusion is used to locate the fault.It is hoped that the method of multi-terminal traveling wave fault location based on the two-terminal theory can be used to detect the faults of the real power grid and improve the work efficiency through simulation and experiment.This paper combines the simulation test with the actual work process,according to the method proposed in this paper,Zhangbei County,Zhangjiakou,is selected as an investigation case.The effectiveness of the ranging method is verified by real accident problem,realizes the accurate location of line faults to ensure that the ranging results are closer to the true value.