中文摘要：

为了解决过分相给牵引供电系统带来的问题，研究了三电平三相-单相二极管箝位变换器，把三电平三相-单相变换器用作牵引变电所核心设备，搭建了基于此变换器的贯通式牵引供电系统。分析了三相变换器数学模型，设计了变换器控制系统，研究了单相变换器在贯通式牵引供电系统中的并网控制。利用Matlab／Simulink建立了三变电所贯通式牵引供电系统，仿真验证了该系统架构以及三相-单相变换器的控制性能和并网性能，证明了该系统的可行性。

英文摘要：

In order to solve the problems of neutral sections disadvantages that exist in current domestic electric railway, the three - level three - phase to single - phase diode - clamped converter was studied. The converter was used as the core equipment of the traction substation and an co - phase connected traction power supply sys- tem based on three - level three - phase to single - phase diode - clamped converter was constructed. The mathe- matical model of three - phase converter was analysed. The control systems of the converter were designed. The grid - connected control of the single - phase converter in co - phase connected traction power supply system was studied. A three - substation co - phase connected traction power supply system was built with Matlab/simulink. The configuration of three - substation system , the control and the grid - connected performance of the three - phase to single - phase converter were validated and the feasibility of this system was certified.