一种电缆-架空线混合线路的故障测距算法

A Fault Location Method for Hybrid Transmission Line Consisting of Power Cable and Overhead Line

针对电缆-架空线混合输电线路电气参数不一致的问题,提出一种基于连接点电压比较分段的故障测距算法。该算法基于输电线路的分布参数模型,提取线路两端的电压、电流值并计算正序分量,按电缆、架空线各自的电气参数推算各连接点处正序电压,通过比较其幅值大小来确定故障发生区段,然后利用故障区段两端连接点处电压,按传统单一输电线路双端电气量测距原理计算故障距离。理论分析和MATLAB仿真表明,该方法能准确确定混合输电线路故障位置,且几乎不受不同步相角差和过渡电阻的影响。

A two-terminal fault location method based on comparing positive sequence voltage of connection points is proposed according to the parameters inconsistencies of hybrid transmission line consisting of power cable and overhead line. The algorithm based on the distributed parameter model of transmission lines, uses the voltage and the current obtained from both hybrid line ends to acquire junction voltage and compare its magnitude to discriminate the fault happened in cable or overhead line, then uses the voltage and the current obtained from both fault line ends calculate the fault location the same as traditional double-terminal method. Theoretical analysis and the simulation of MATLAB show that the proposed scheme can accurately measure the hybrid transmission line fault location and be also applied to more complex hybrid transmission lines.