冲击响应特性在轨地过渡电阻检测中的应用

曹晓斌1叶俊2王满想3季耀政1简明华1谢金洋1

Application of Impulse Response Characteristics in Rail-ground Transition Resistance Measurement

CAO Xiaobin1YE Jun2WANG Manxiang3JI Yaozheng1JIAN Minghua1XIE Jinyang1
摘要:
[目的]城市轨道交通线路杂散电流的危害越来越不容忽视。杂散电流不易检测,轨地过渡电阻的大小是影响杂散电流最关键的因素,因此,通过检测轨地过渡电阻的大小来判断杂散电流的影响程度,是治理杂散电流的有效方法。[方法]基于EMTP(电磁暂态程序)软件,搭建了轨道电路分布参数仿真模型。采用单一控制变量法,分别得到了分布电容、分布电感、钢轨纵向电阻、轨地过渡电阻对冲击阻抗时变特性曲线的影响规律。提出利用冲击阻抗时变比值曲线来判断轨地过渡电阻是否符合要求的方法,并对成都某条城市轨道交通线路进行了实际测量,对该方法进行了验证。[结果及结论]7~20μs时间段内,仅轨地过渡电阻1个参数对冲击阻抗时变特性造成影响。可利用此特征下的冲击阻抗时变特性来反映轨地过渡电阻情况,并对轨地过渡电阻值是否满足规范要求进行有效判断。实测结果表明,该检测方法具有可行性和实用性。
Abstracts:
[Objective] The stray current harm in urban rail transit lines is increasingly non-ignorable. Stray current is not easy to be detected, and the amount of the rail-ground transition resistance is a crucial factor affecting stray current. Therefore, measuring the amount of the rail-ground transition resistance is an effective stray current control method to judge the influence degree of stray current. [Method] Based on EMTP (electromagnetic transient program) software, a simulation model of the track circuit distributed parameters is built. The respective influence patterns of the distributed capacitance, distributed inductance, longitudinal resistance of the steel rail, and the rail-ground transition resistance on the time-varying characteristic curve of impulse impedance are obtained by using the single control variable method. The method of using impulse impedance time-varying ratio curve to judge whether the rail-ground transition resistance meets the requirement is proposed, and further verified by actual measurement of an urban rail transit line in Chengdu. [Result & Conclusion] Within 7~20 μs, only the rail-ground transition resistance parameter may affect the time-varying characteristics of the impulse impedance. Therefore, it can be used to reflect the condition of the rail-ground transition resistance and make valid judgement on whether the rail-ground transition resistance meets the requirement in the specification or not. Test results show that the measuring method is feasible and practical.
论文检索