利用多时刻信息的T接线路单相接地故障单端测距方法

Single Terminal Fault Location to Single-line-to-ground Fault in T Transmission Line Based on Sequenced Time Session Data

T接输电线路受实际应用中多端同步信息缺失或精度差等影响,难以实施精确故障测距。基于永久性接地故障单相断路器跳闸前后输电线路拓扑结构保持不变的实际,立足于最后跳闸的分支电源端,利用三端故障相依次跳闸而产生的多时刻信息,提出一种新型的单端阻抗测距算法。给出多时刻输电线路拓扑结构的准确描述方程组,提出基于改进高斯–牛顿法Levenberg-Marquardt方法的故障测距算法,能准确计算出故障距离和过渡电阻值,仿真验证了算法的有效性。该研究思路也可拓展应用到可再生能源接入的输配电网系统中,具有重要的理论和实用价值,但尚有关键技术问题亟待后续研究。

The accurate fault location in T connection transmission line is pretty difficult in real applications due to the unavailability of synchronized three-terminal fault data.In response to this problem,a novel single-terminal fault location algorithm was proposed with only using the data at the last-tripping power source side.It is based on the fact that,the topology of transmission line keeps constant in the sequenced time-sections produced by the single-phase circuit breaker tripping separately at three ends.The detailed description forums of transmission line topology in sequenced time-sections were presented,and a resolving algorithm based on Levenberg-Marquardt method was proposed.The algorithm can simultaneously resolve out the accurate fault distance and the value of fault resistance.High accuracy of the algorithm was proved with different fault simulation cases.The most valuable theory innovation can also be extended to the practical applications in transmission and distribution system with renewable power source connections,but several key technical problems should be further researched in following.