消除单端行波测距死区的煤矿电网故障定位

Study on one terminal traveling wave fault location for coal mine high-voltage power network under the consideration of dead zone

单端行波故障定位由于故障行波特征难于分辨,故障距离若与非故障线路基本特征匹配时,导致单端行波测距方法无法完成,因此输电网中实用的故障定位均为基于GPS精确校时的双端行波法。在深入剖析煤矿中压电网发生故障后的行波传递的基本特点的基础上,充分考虑煤矿电网馈线支路多、线缆混合情况等矿区电网的特点,对单端行波故障定位原理特点作深入分析。定义行波瞬时功率,改进了电压、电流行波易受线路中噪声影响的问题,提高了信号的可测性;并根据选线结果及线路本身参数,利用故障线路中两个反应故障距离的反射波头时间关系验证反射波头,解决单端行波定位的死区问题。PSCAD/EMTDC仿真实验表明,该故障定位方法具有较高的精确度,完全能适应煤矿电网的特点。

Abstract：As the reflected waves based on one terminal traveling wave fault location is distinguished hardly, even when fault distance is identical with non-fault feeders, the wave fronts arrive simuhaneously-the dead zone of fault location, thus double terminal methods are applied using Global Positioning System clock synchronization. In this paper, charac- teristics of traveling waves propagation for coal mine high-voltage power network was studied, some factors were taken into consideration, such as so many feeders and its overhead-cable mixed lines, then one terminal traveling wave fault location was deep analyzed. Traveling wave instantaneous power was defined, compared with traditional voltage or current traveling waves, its anti-noise performances were improved. Then the parameters of feeders combined with line se- lection was used, the mathematical relation between reflected waves from fault point and from the far end terminal bus was applied to identify one of them, the dead zone was resolved based one terminal traveling wave fault location. Many simulations show that coal mine high-voltage power network is completely adapted by fault location algorithm proposed by authors with high accuracy and adaptability. Key words： coal mine power network ; power cables ; traveling-waves-based fault location ; traveling wave instantaneous power