行波法与阻抗法结合的综合单端故障测距新方法

提出了一种基于小波变换模极大值的行波法与阻抗法相结合的单端故障测距方法。首先用行波法进行单端故障测距,利用故障点的反射行波与入射行波到达测量端的时间差计算故障距离。行波法不用区分故障点的反射波和对端母线的反射波以及相邻线路的折射波,故得到多个测距结果,再用单端阻抗法对行波法测距结果进行筛选,选择最接近的一个结果作为最终测距结果。仿真计算表明,所述测距方法不受故障类型、系统运行方式等因素影响,鲁棒性较强。

Non-communication Fault Locating of Transmission Line Based on Traveling Wave and Impedance Method

A new single-terminal fault locating method based on the traveling wave of wavelet modulus maxima combining with impedance method is presented. Firstly, using the traveling wave method, the fault distance is calculated based on the interval between the incident traveling wave and the reflected traveling wave from the fault point in the fault locating terminal. But it is difficult to distinguish between the reflected traveling waves from the fault point and from the remote bus. The innovation in this paper consists in no need to distinguish the reflected traveling waves from the fault point and from the remote bus, as well as the refracted traveling waves from the bus. For many fault locating results based on traveling wave, the single terminal algorithm which measures resistance filtrates the fault locating results and chooses one near to the fault locating result. Simulation results show that the method presented is not affected by the fault position and the fault modes, and is diminutively affected by the transient resistance and the change of power system operating modes. Also it is quite robust and highly practical.