利用两端非同步电流的同杆双回线故障定位研究

提出一种利用双端非同步电流实现同杆双回线故障定位的时域方法.根据双回线环流网两端电压为零的特点,用电流量计算环流网的沿线电压分布;在设定的双端数据不同步时间范围内,通过数据移动进行数据同步匹配搜索;根据数据同步时由两端电流计算得到的沿线电压分布在故障点处差值最小的原理,构造测距算法实现测距.采用分布参数线路模型,该算法可适用于高压长距离输电线.ATP仿真表明该测距算法精度高,不受故障类型和过渡电阻影响.

Fault Location Algorithms for Parallel Transmission Lines Using Two Terminals Nonsynchronized Current Data

A novel time-domain algorithm of fault location for parallel transmission lines on the same tower is presented in this paper. Considering that the parallel transmission lines can be decomposed into Common Component Net and Differential Component Net, the voltage distributions along Differential Component Net can be calculated with two-terminal current samples only. The new algorithm is based on the fact that the difference between voltage distributions, calculated with two terminal synchronized currents, is smallest at fault point. The synchronization is achieved by searching the minimum of the fault locating criterion. No voltage-sample is used, so the proposed algorithm is independent of the weak transferring ability of CVT. The algorithm needs a short data-window, which is just a little longer than double propagation time of parallel transmission lines. From transient to steady state, any segment of fault data can be used to locate faults. The distributed parameter transmission line model is used to improve locating accuracy, and simulations show that the locating errors are less than 150 meters. Additionally, the fault types and fault resistance have no influence on the precision.