| Compared with single circuit line,double circuit line on the same tower has stronger transmission capacity and better stability,which has been widely used in power system.However,due to different geographical conditions and the influence of power supply demand,there is a mixed erection of single circuit line and double circuit line.At present,there are few researches on the non full length double circuit transmission lines on the same tower.Compared with the traditional single circuit transmission lines and double circuit transmission lines,the non full length double circuit transmission lines on the same tower have great differences in line structure,and the fault situation is more complex.Therefore,the research on the fault location of the non full length double circuit transmission lines on the same tower is very important.This paper studies the problem of distance measurement of the non full length double circuit transmission line with the same pole.Firstly,the positive and negative phase characteristics of the fault section identification function group are used to determine the fault section.On the basis of determining the fault section,a fault location method based on ele tromagnetic time reversal is proposed.After decoupling the voltage and current on both sides of the fault section,if the double circuit section fails,the same mode voltage and current are fast Fourier transform.If the single circuit section fails,the 1-mode voltage and current are fast Fourier transform,the current forward traveling wave under the working frequency component is extracted,and the power frequency current forward traveling wave is conjugate,Then calculate the current effective value at each fault point assumed,and when the effective value is the minimum,the point is the fault point.In the process of fault location for non full length double circuit transmission line on the same tower,the simulation model of non full length double circuit transmission line on the same tower is set up by using ATP/EMTP simulation software,and the relevant algorithm program is written by using MATLAB software.The simulation results show that the frequency domain forward current method based on EMTR theory can be applied to all kinds of fault types,and the results are not affected by the transition resistance and different phase angles of two terminal power supply,And it can effectively solve the error problem caused by incomplete synchronous sampling of two terminal data.The feasibility of forward current method in frequency domain based on electromagnetic time reversal is proved. |
