摘要
提出了一种基于节点阻抗矩阵的配电网故障测距改进算法,故障后,系统的网络拓扑结构及参数会随之改变,引起节点阻抗矩阵的变化,形成故障后的节点阻抗矩阵,其中含有未知量故障距离和过渡电阻,利用节点阻抗的物理意义建立测距表达式。该算法仅需要变电站出线电压、电流作为输入量,迭代计算故障区段上游母线的电压、电流,代入已建立的测距表达式求出故障距离和过渡电阻;为适应配网中负荷特性不统一、时变的特点,提出采用静态电压特性的负荷模型模拟负荷,采用此模型可以更加精确地计算故障后各负荷及分支的分流,使得故障测距结果更加准确;并提出结合配电系统的馈线自动化功能减少伪故障点个数实现故障点的定位;文章最后在PSCAD中搭建配电网IEEE 34节点模型,在Matlab中实现文中提出的故障测距算法,仿真测试表明该算法的有效性。
A nodal impedance matrix based improved fault location algorithm for distribution network is proposed. The topological structure and parameters of distribution network will change after the fault and it leads to the change in nodal impedance matrix, in other word, the post-fault nodal impedance matrix in which the unknown fault distance and transition resistance are involved, is formed, thus based on physical meaning of nodal impedance the expression of fault location can be established. For the proposed algorithm, only current and voltage of substation outgoing line are needed as the input variables, and the voltage and current of the bus located at the upstream of the faulty zone can be calculated by iteration, and substituting the calculation results into the established fault location expression the fault distance and transition resistance can be solved. To suit the features that the load characteristics in distribution network are time-varying and not unified, it is put forward that the load in distribution network is simulated by the static voltage characteristic based load model, and adopting such a model the post-fault loads and the shunts in branches can be calculated more accurately to make the result of fault location more accurate; it is also put forward that combining with the feeder automation function of distribution network the number of pseudo fault points can be reduced and it is helpful to fault location. A model of IEEE 34-bus distribution system is constructed by PSCAD, and the proposed fault location algorithm is implemented in Matlab-based environment. Simulation results show that the proposed fault location algorithm is effective.
出处
《电网技术》
EI
CSCD
北大核心
2013年第11期3233-3240,共8页
Power System Technology
基金
国家863高技术基金项目(2012AA050208)
国家电网公司科技项目(KJ[2012]1107)~~
关键词
配电网
故障测距
节点阻抗矩阵
静态电压特性负荷模型
distribution network fault location nodal impedance matrix static voltage characteristic based load model
