Study Of Traveling Wave Fault Location On Catenary System For Electric Railway

The catenary traveling wave fault location is very important to guarantee the electric railway operating smoothly and safely. The paper discussed the research on the power system traveling wave transmission line fault location at home and abroad. Combining with the characteristics of elctric railway catenary fault, this paper provided a comprhensive fault location method, that is, A-type traveling wave fault location method combining B-type traveling wave fault location as the main methods, and supplemented by C-type traveling wave fault location.This paper systematically studied the wave equation of the transmission line grounded fault, phase mode transform,fault transient traveling wave propagation, wavelet analysis basic theory and singular signal detection theory.Using electromagnetic transient simulation software ATPDraw,different simulation modeles which work under different operating mode,different fault location,different fault resistance circumstances, and the modeles when permanent catenary fault occurred,were built in the AT and trolley rail negative feeder power supply mode.At the same time, this paper detailly explanated the main simulation model icons.At last, the voltage and current traveling wave signal were calculated by simulation.Using the program of A-type traveling wave fault location in Matlab,the current traveling wave signals which were calculated from the simulation under some circumstance, eg, whether locomotive power supply load or not,the fault resistance,fault moment voltage phase, whether the parallel capacitance compensator group working or not in the traction substation,were detailly studied.The wavelet transform modules maxima graphicsis were given and the fault distances were calculated.The above circumstances almost do not affect the results of A-type traveling wave fault location method.This paper described the traveling wave velocity.The traveling wave refraction and reflection theory is applied in the catenary fault location, analyzing the main traveling wave signal which arrive the measuring point, and differentiate an effective information from all traveling wave singles.According to the catenary transient traveling wave signal, this paper selected third-order B-spline wavelet as the basic wavelet, and identified with the corresponding filter coefficients .Using wavelet transform and singularity detection theory, the location of the singular points were detected, the fault location-specific stepsof catenary were given.A-type,B-type and C-type traveling wave fault location program were developed,and sequence diagrams were also provided in this paper to interpret the consideration of programs.Using the first two location algorithm,this paper analyzed the different wave signals which obtained under different operating modes,drew some important conclusions.The location algorithms applied the different fault locations under the trolley rail negative feeder power supply mode and AT power supply mode, comprehensive fault locations presented the results.Results show that the comprehensive fault locations can be effective and reliable method to achieve the traveling wave fault precise positioning. Finally introduced Catenary traveling wave fault location device.