直流牵引供电系统的短路试验是验证直流牵引供电系统各设备在系统现场短路时动作的正确性和可靠性的重要环节。以武汉轨道交通4号线二期工程现场直流牵引供电系统短路试验为例，介绍短路试验的前提条件，试验程序和试验方法。试验前，人为设定一个短路点，检查断路器等保护元器件是否正常，连接好数据采集系统以采集短路时的电流、电压等波形，用Matlab软件搭建短路时的电路模型对预期短路电流进行仿真计算；试验后，对短路试验的实际数据与仿真数据进行分析，得出开关保护动作正常可靠，并计算出实际的分断电流大小为8.15KA，为直流牵引供电系统短路试验的进一步研究提供参考。

Short circuit test of DC traction power supply system is an important step to verify the correctness and reliability of DC traction power supply system equipment during short circuiting. Using DC traction power supply system short circuit test for Wuhan Rail Transit Line 2 extending vehicles as an example, this paper introduces precondition, process and method of short circuit test. Before test, a short - circuit point is set artificially, with circuit breakers and other protection components being normal. Then the data acquisition system is connected to acquire short - circuit current and voltage waveforms and the prospective short - circuit current is simulated by using Matlab. After test, the practical data of short circuit test is analyzed to provide some reference for further study of short circuit test of DC traction power supply system. It is concluded that the protection operation of the switch is proper and reliable. The actual breaking current size is calculated to be 8.15 kA. This study will surely provide reference for the further study of the short circuit test for DC traction power supply system.