Study On The Technical And Economic Character Of Cable-Powered Electric Railway

With the development of Chinese electric railway, the issues of its power quality become increasingly prominent, where the problem of negative sequence is particularly prominent. In the existing power supply system, frequently passing electrical phase splitting sections seriously restricts the train speed and the performance of the power supply ability, the part of electrical phase splitting sections has become a technical bottleneck of the development of Chinese high-speed and heavy haul railway. The new cable power supply plan proposed by Prof. Li Qun-zhan removes the electrical phase splitting sections of the traction network in traditional power supply model, implements cophase power supply, which improve the traction power supply ability and becomes a new idea of high-speed and heavy haul railway development.Firstly, this thesis analyses the structure principle of the new cable power supply plan, expounds its advantages and application prospects, secondly introduces the calculation method of the matching substation capacity design, and provides the calculation method of the feeder current. After that,this thesis introduces the feature of the 110kV power supply cable, and provides the cable current carrying capacity under the influence of cross-section and laying pattern of the power cable; Last, this thesis introduces the structure principle of the center substation, providing the capacity design approach of the single-phase combined cophase power supply system and analyzing the capacity calculation approaches of the traction transformer as well as the cophase power supply device.On this basis, this thesis applies the new cable power supply plan to Da-Qin railway. Contraposing its load feature, the matching substations, the 110kV power cables and the center substations have been designed and configured. And then from the factors of external power source investment, equipment utilization rate, investment of passing electrical phase splitting sections, yearly transportation and the utilization of regenerative braking energy, the new cable power supply plan has been compared with existing power supply system, which presents the economy advantage and technical superiority of the new cable power supply plan.Finally, this thesis uses’vensim’software to build system dynamics model of the new cable power supply plan for Da-Qin railway, entirely and dynamically evaluates the related factors. By analyzing simulation results, the economy efficiency of this new cable power supply plan for Da-Qin railway has been evaluated.