城市轨道交通钢轨电位异常问题研究

Study on Abnormal Rail Potential Problem in Urban Rail Transit

针对国内某地铁线路出现的车辆段和正线钢轨电位限制器(OVPD)频繁动作的问题,搭建了综合考虑正线和段场的回流系统仿真模型,研究正线和段场钢轨电位的传播机理。在某停车场及邻近3个正线车站进行了同步试验,通过对单向导通装置电压、电流以及钢轨电位的测试结果进行分析,利用供电仿真模型还原了该线路正常运营期间单向导通装置对停车场和正线钢轨电位的影响过程,得出结论:设置单向导通装置会恶化段场钢轨电位并导致OVPD动作;段场OVPD分合闸过程中会产生操作过电压,该过电压会通过单向导通装置传递至正线,进而导致正线车站Ⅰ段甚至Ⅱ段OVPD动作。

With regard to the problem that the overvoltage protection device(OVPD)of rolling stock depot and main track are acted frequently in a subway line in China,a simulation model of return current system is built,with consideration of return current system in main track,station and yard,for study on the propagation mechanism of rail potential in the main track,station and yard.Synchronous tests are conducted at a parking lot and three adjacent main track stations.By analyzing the test results of the voltage,current,and rail potential of the unidirectional conduction device,a power supply simulation model is applied to restore the influence process of the unidirectional conduction device on the rail potential of parking lot and main track during normal operation of the line,and the conclusions are obtained:Setting a one-way conduction device will worsen the potential of the track in the depot and cause OVPD action.During the opening and closing process of the OVPD in the depot,an operating overvoltage will be generated,it will be transmitted to the main track through a one-way conduction device,leading to the operation of the OVPD in section I or even section II of the main track station.