为了解决电网故障双端行波定位中任一定位装置故障、启动失灵或时问记录错误等导致的定位失败难题,提出了基于网络的故障行波定位算法,根据电网中故障行波到达各变电站的精确时问和行波传输的最短路径进行综合定位计算。运用Floyd算法计算电网的最短路径矩阵,匹配行波波头到达各变电站的精确时间;分析不经过故障线路的最短路径,在线计算行波传播速度;并寻找经过故障线路的最短路径,在线计算故障点位置;为每个变电站设置权重,对所有不同路径的计算结果加权求和,得到故障点的精确位置。EMTP仿真分析和现场运行结果表明,该定位算法误差小于150m,可靠性高、鲁棒性强,较好地满足了电网运行要求。
In order to solve the problem of location failure on the traditional both-terminal traveling waves based power line fault location caused by any fault in locating equipment, startup failure and time record error, a network-based fault location algorithm with traveling wave is developed, and the fault position is calculated by using the traveling wave arrival time to every substation of the power grid and the shortest routes of the traveling wave transmission. Firstly, the power grid shortest routes matrix is calculated by the Floyd algorithm, and the first-traveling wave arrival time to every substation is sought. Then the shortest routes that do not pass the fault line are analyzed, traveling wave velocity is calculated online; and the shortest routes that pass the fault line are also sought, the fault locations can thus be calculated. Finally, setting every substation's weight, an accurate fault location can be obtained by fusing all the fault location results for different routes using weight average. EMTP simulations and power grid tests show that the location algorithm is with error no more than 150 m, high reliability and strong robustness. It can satisfy the requirement of power grids operation.