Study On Fault Location Of Power Supply System Of Metro Traction

With the acceleration of rail transit construction, the importance of the subway is increasingly apparent. And the role of traction power supply system is obvious. Taking into account the third rail and the running rail as the main fault place and it without reserve characteristics, it is more and more important to quickly and accurately find the fault position firstly, because it can reduce the outage time and economic losses due to failure.The traction power supply system is analyzed. Models includes the 24 pulse rectifier, third rails, running rails and the locomotive etc are established. The paper uses the model locomotive starting and fault simulation to verify the accuracy of the model. The characteristics of the voltage and current characteristics of the metallic short circuit and the non metallic short circuit fault are obtained.To consider the influence of the skin effect on the circuit parameters.The paper derived relationship between the skin depth and the impedance of skin effect. In Ansoft finite element software, a model is established. And a method of finite element and equivalent cylindrical method is proposed, which is characterized by the characteristics of the skin effect of the normal load flow, the occurrence of metallic short circuit faults, and the characteristics of the non metallic short circuit faults. And the effect factors of the skin effect of metal short circuit fault are analyzed. The parameters of the fault are calculated.According to the above, In this paper, a method of non metallic short circuit fault location based on L-M parameter identification is proposed. The algorithm program is written in MATLAB. The accuracy of the algorithm is verified by simulation data. The influence of the factors such as the parameter uncertainties, increase of the resistance, the flow of the locomotive on the accuracy of the distance measurement is studied.According to the characteristics of metal short circuit fault, this paper set up the third and running rail model, which based on the analysis of the skin effect. In the MATLAB, the ant colony optimization algorithm program is proposed and written. And the accuracy of the algorithm is analyzed in the range of fault impedance, distance. The influence of error factors on the ranging accuracy is analyzed...