基于视在波速的电缆故障行波测距法

在电缆故障行波测距法中,行波在传输过程中会发生畸变,甚至出现反射行波真实起始点被噪声淹没而 不能探测的现象,故用反射波上升沿中间段部分数据拟合出的二次曲线与坐标轴交点为视在起始点,用最小二乘 法建立电缆故障点距离与视在起始点之间的联系。由于视在起始点受噪声的影响比较小,且视在波速来自实验数 据的曲线拟合,故测距精度较高(误差<2m)。

Cable Fault Location Based on the Apparent Traveling Wave Velocity

In the cable fault location based on the traveling wave, the traveling wave is often distorted by the cable loss and the plentiful high frequency components in the injected signal, more often the reflected wave can't be detected because the real jumping-off is submerged by the noise. In this paper, some data of the reflected wave on the rising edge is utilized to fit the curve and get the apparent jumping-off of the reflected wave. The apparent wave velocity is defined and acquired from the experimental data, and as a result the relationship between the apparent jumping-off and the cable fault location is set up. Because the apparent jumping-off is influenced little by the noise and the apparent wave velocity is gotten from the experiment, the cable fault location based on the apparent wave velocity has higher precision.