存在支路的AT全并联供电系统精准故障定位研究

Study on Accurate Fault Location of All Parallel AT Power Supply System with Branches

AT供电方式在牵引供电系统中得到广泛应用。传统的测距方法仅针对串联型线路拓扑测距较准确,对于存在支路的线路拓扑已不再适用。本文针对上述特殊情况,根据实际现场的接触网参数搭建含有支路的AT全并联供电方式的六导线模型;在大区间内根据基尔霍夫定律列写电压、电流与故障距离的矩阵方程,推导出故障距离与电流及线路参数关系式,准确计算故障发生时主干线路与支路线路上故障所在位置。最后利用RTplus牵引供电系统实时数字仿真仪对支路在不同位置的拓扑结构进行测试,在支路与干路不同位置进行不同类型的故障模拟,测试结果误差满足工程要求,验证了方法的可行性和准确性。该方法不受故障区间及故障类型的影响,具有很好的普适性,为存在支路的AT全并联供电系统故障测距提供了一种思路。

AT power supply mode is widely used in traction power supply system.The traditional distance measurement method is only more accurate for the topology of series transmission lines,but it is no longer applicable for the topology of transmission lines with branches.The paper,with regard to the above-mentioned problems,establishes a six-wire model for all parallel AT power supply mode in accordance with the OCS parameters obtained from the actual site,writes the matrix equations of voltage,current and fault distance in a large section on the basis of Kirchhoff’s law,derives the relationship between fault distance and current/line parameters,calculates accurately the location of fault on the main and branch lines when faults occur.Finally,the real time digital simulator of RTplus traction power supply system is used to test the topology structure of the branch at different locations,and different types of faults are simulated at different locations of the branch and mainline.The feasibility and accuracy of the method are verified since the errors of test results meet the engineering requirements.The method is not affected by the fault section or fault types,it has good universality and is able to provide a way of thoughts for fault location of all parallel AT power supply system with branches.