Study On The Reliability Of Cable-Powered Electric Railway System

In recent years, as the rapid development of the railway electrification system, the cable-powered electric railway system becomes more and more important. Therefore, the requirement of the safety and reliability of the system become more important. In our current power electric railway system, electrical sectioning must due to the different phase feeding method we use. Therefore, the trains passing neutral section frequently and some problems may occur, such as the power interrupt, tractive force decrease and the quality problem of the negative power which can affect the safety of the system. However, using the technique of the new cable-powered system can not only solve all the problems but also can bring many other benefits such as improve the ability of power supply, guarantee the capability of transportation and improve the reliability of the system.We mainly focused on the theoretical aspect of the new cable-powered electric railway system and explained the advantages of the new system and its application prospect. An analysis of the safety of the new cable-powered system is very important in order to have a deep understanding of the new cable-powered system. In this thesis, we put forward a basic framework of the new cable-powered system and its reliability. We divided the new cable-powered electrical supply system into the following levels:central substation, layer cable, traction substation and catenary.Firstly, we applied’GO’method on the central transformer substation and produced the ’Go’plot according to the two main wiring circuit of the central transformer substation. We simplified the’GO’plot and worked out the programming code using MATLAB and did the quantitative analysis and qualitative analysis. Thus we can found the weakness of our central transformer substation was conducted.Secondly, we did a reliability analysis of the other three levels. As for the cable, we analyzed the research status of the reliability of the cable and we build a reliable model of the cable in the new cable-powered electric railway system. Three alternative scheme was given and we analyzed them one by one, after compare the reliable indexes, the best scheme was selected. We also build a model of the transformer substation and conducted a reliability analysis of the current indexes of the catenary and the reliable indexes obtained.Finally, we did a reliable analysis of the new cable-powered electric railway system based on the methods above, we applied fuzzy comprehensive appraisement theory on the allocation of the reliability, we allocated the reliability indexes of the whole system into the different subsystems and thus the improvement of the system was achieved.