【作者】 范伟；

【导师】 宋世德；

【作者基本信息】 大连理工大学 ， 结构工程， 2012， 硕士

【摘要】 目前的地铁和轻轨主要采用直流供电,车辆在运行过程中由于轨道绝缘方面的问题会产生杂散电流,不仅导致结构钢筋损耗,也容易造成地下管线腐蚀穿孔,危害结构和人民生命财产的安全,造成严重的经济损失。由于地铁杂散电流的客观存在,因此研究地铁杂散电流的分布对杂散电流的控制和危害的消除具有很重要的意义。通常研究人员采用传统仿真方法对杂散电流的分布进行研究,但存在推导公式复杂,不能模拟单点或多点绝缘破坏,因此本文提出一种利用Pspice进行仿真的新方法。该方法的实质是通过编程生成地铁杂散电流电阻网络模型,通过基尔霍夫电压定律和电流定律直接计算复杂电阻网络的节点电压和每个元件的电流。本文采用新的模拟方法分别模拟单边和双边供电杂散电流的分布规律,同时研究了不同的轨地过渡电阻率,供电电流和供电区间长度对于杂散电流的影响，得到如下结论：(1)基于Pspice的模拟方法与基于微分方程的模拟方法在模拟不排流,全线绝缘的工况时得出的数据误差很小,均在5%以内。这说明基于Pspice的模拟方法是有效的。(2)全线绝缘的情况下,不排流时,轨道电流,杂散电流均是抛物线分布。轨道电流在中点处于最小值,而杂散电流在中点处于最大值；排流时,轨道电流与杂散电流为半抛物线分布。轨道电压为直线分布,在牵引变电站处为0V,而在列车处取得最大值,且最大值是不排流时的两倍。(3)随着轨道上泄漏点数目的增加,轨道电流降低,杂散电流升高。随着轨地过渡电阻率的减小,轨道电流降低,杂散电流升高。随着供电电流的增加,轨道电流,杂散电流,轨道电位最大值成比例的增长。随着供电区间长度增加,轨道电流降低,杂散电流升高。(4)与单边供电相比,双边供电轨道电压较小,且杂散电流也远小于前者。更多还原

【Abstract】 With the DC power supply of subway, the running rail may produce stray current, not only led to loss of structural steel even reducing the safety of the structures but also result in perforation of the underground pipeline and causing serious economic losses. Therefore, studying the distribution of the stray current will reduce the stray current leakage significance.It’s researched that the traditional simulation method has a huge flaw. In consideration of the limitations of traditional methods, this paper developed a simulation method based on Pspice. Kirchhoffs voltage law and current law are used to calculate of the voltage and current relationship in the complex resistor network, thus voltage, input current and output current at any node are obtained.The simulation method based on Pspice simulates working conditions in unilateral and bilateral power supply. The distribution of stray current under various rail-ground resistivity, the supply current and the distance between traction substations is drawed. It mainly concludes:(1) The simulation method based on Pspice and the simulation method based on differential equation in drainage and no-drainage reach a very small data error that is less than5%. It’s showed that the simulation method base on Pspice is effective.(2) Under electrical insulation without current drainage, the distribution of rail current and stray current is parabolic. In the mid-point railway current is at a minimum, and stray current is at a maximum.Under electrical insulation with current drainage, the distribution of rail current and stray current is semi-parabola. The distribution of rail potential is straight line, at the traction substation is zero, at the train is the maximum value, and the maximum is as twice as the value without current drainage.(3) With the leak points increased, the rail current is reduced, stray current is increased. With the decrease of the rail-ground resistivity, the rail current is reduced, stray current is increased. With the increase of locomotive current, rail current, stray current, the maximum rail potential proportional to the growth. With the increase of power supply length, the rail current is reduced, stray current is increased.(4) Compared with the unilateral power supply, bilateral power supply can effectively reduce the rail potential and stray current.更多还原