为了解决行波波速的不确定性对故障定位影响的问题,针对T型输电线路,提出一种不受波速影响的故障定位方法。该方法主要包含两个部分:故障支路判断矩阵的建立和故障点的精确定位。首先,根据故障初始行波到达时刻建立一种新的故障支路判断矩阵,利用该矩阵的元素特征实现故障支路的判断,同时该矩阵不包含行波波速的任何信息;其次,在双端行波故障定位原理的基础上推导出一种与波速无关的故障点定位方法。理论推导表明,该方法两部分均不受行波波速的影响。仿真结果表明,所提方法能够准确检测到故障初始行波到达测量点的时刻,进而确定故障支路,并精确定位故障点。该方法消除了行波波速对故障定位的影响,同时,定位精度不受故障类型和过渡电阻的影响。
The uncertainty of traveling wave speed always causes big deviations to the fault location. In order to conquer the influence of traveling wave speed on transmission line fault location, a new method of fault location independent of wave speed by using three measurement points was presented in this paper. The method contains two main parts: the establish- ment of the identification matrix for the faulty section and fault point location. Firstly, the arrival times of the initial fault traveling waves are used to form the identification matrix for the faulty section, and the faulty section can be identified ac- cording to characteristics of element in the formed identification matrix, and the matrix avoids the influence of wave speed; Secondly, a new locating algorithm without influence of wave speed is derived based on the principle of double-end trave- ling wave fault location. The simulation results show that the arrival time of initial fault traveling wave can be detected ac- curately, and then, the faulty section and the fault point can be located exactly by using the method proposed by this paper. And the method is unsusceptible to wave speed, fault type, transition resistance.