摘要
针对城市轨道直流牵引供电系统短路故障定位困难的问题,提出了一种考虑轨地回路分布式参数的双端稳态故障测距算法。在发生短路故障后,利用故障区间相邻牵引变电所馈线直流开关柜的测试电路将直流牵引网电压施加在接触网与钢轨之间,利用2次测量的牵引网端口电阻进行故障测距。在考虑钢轨-大地两层回流结构的基础上,对分布式参数的轨地回路进行T型等效,通过解析计算得到故障距离与端口电阻的表达式。该方法不需要增加额外的故障测距设备且不需要双端数据的同步,不受接触电阻和暂态过程中的钢轨阻抗频率特性的影响。利用CDEGS仿真软件模拟直流牵引供电系统故障,讨论了不同接触电阻、故障点位置、过渡电阻以及电压、电流测量装置测量误差对故障测距精度的影响。在实验室小功率平台上采用裸导线模拟完全绝缘和较低过渡电阻的2种情况,结果验证了所提故障测距算法的有效性和实用性。
To overcome the difficulty of locating short circuit faults in DC traction power supply system for urban rail transit,a two-terminal steady state fault location algorithm based on the distribution parameters of rail-earth reflux system is proposed.A DC traction network voltage is applied between catenary and rail by the test circuit of feeder DC switchgears of traction substations adjacent with the fault interval after short circuit faults.The fault location is calculated by using port resistance of traction network measured twice.Considering the double layer rail-earth reflux structure,the T-type equivalent circuit of rail-earth reflux system with distributed parameters is carried out,the expressions of fault location and steady state currents are inferred.The proposed method requires no additional fault locating equipment and the synchronization of two-terminal data,and is not affected by the short circuit resistance and impedance-frequency characteristic of rail in transient process.The fault of DC traction power supply system is simulated in CDEGS software.The influences of different short circuit resistances,fault point locations,transition resistances and measuring errors of current and voltage measuring devices on fault locating accuracy are discussed.The effectiveness of the two-terminal steady state fault location algorithm is verified by the simulation of complete insulation and low transition resistance using bare conductor on laboratory small power platform.
作者
刘炜
唐一文
李富强
王竞
LIU Wei;TANG Yiwen;LI Fuqiang;WANG Jing(School of Electrical Engineering,Southwest Jiaotong University,Chengdu 610031,China;China Shipbuilding Industry Corporation No.712 Institute,Wuhan 430064,China)
出处
《电力自动化设备》
EI
CSCD
北大核心
2020年第11期163-168,共6页
Electric Power Automation Equipment
基金
国家重点研发计划资助项目(2017YFB1201002-07)。
关键词
城市轨道
直流牵引供电系统
故障测距
稳态数据
轨地回路
分布式参数
urban rail transit
DC traction power supply system
electric fault location
steady state data
railearth reflux system
distribution parameters
作者简介
刘炜(1982—),男,湖南益阳人,副教授,博士研究生导师,主要研究方向为城市轨道交通牵引供电,E-mail:liuwei_8208@swjtu.cn;唐一文(1995—),女,四川南充人,硕士研究生,主要研究方向为城市轨道交通继电保护,E-mail:136293951@qq.com。
