Research On Transmission Line Fault Ranging Based On Fine Integration Method

Modern power system requirements for power quality and reliability are gradually improving,and transmission lines can be called the blood vessel of the power system,which has a pivotal position in the process of power transmission and distribution.As a large power generation and consumption country,China’s power grid span is very large,the operating environment is very complex,the climate is unpredictable,these reasons caused the type and frequency of faults in China’s power grid is more.Failures in the power grid not only have a serious impact on the power quality and reliability of the power system,but also cause great damage to our economic efficiency and the safety of people’s lives and properties.So how to find the location of fault occurrence quickly and precisely is now the focus of transmission line fault ranging research.This paper introduces a transient analysis calculation method with stable algorithm and simple structure,the fine integration method,to conduct fault ranging research on transmission lines with double-ended transmission line system as the research object,and the main research contents are as follows:(1)Firstly,the method of fault ranging and the fine integration method are introduced,and through the analysis of arithmetic results,it is concluded that the fine integration method is suitable for solving the voltages and currents along various transmission lines.(2)Second,for the previous use of the fine integration method in fault ranging,the 4th order Longacurta method is used in solving the results.This paper uses iterative calculation of the T-matrix in solving the results,which can retain the advantages of the fine integration method in terms of high calculation accuracy and stability of the algorithm,and at the same time,it can also improve the calculation speed.Through the simulation of fault ranging on single-phase and three-phase lines in Matlab/Simulink simulation environment,it is concluded that the fine integration method has better accuracy in fault ranging,and its ranging results also show that using T-matrix for iterative calculation is better than using the 4th order Longacurta method.(3)Finally,in order to solve the problem that improving the accuracy of the fine integration method in fault ranging will reduce its calculation speed,this paper proposes to use the sub-domain fine integration method for fault ranging,and then through simulation calculations,it is concluded that the accuracy and speed of the sub-domain fine integration method are better than the fine integration method.After the above experimental analysis,it can be concluded that the fine integration method is very suitable for transmission line fault ranging.It has a positive effect on ensuring the power quality and reliability of the power system.