基于多重判据的电压暂降故障源定位方法

Multiple Criterions Based Voltage Sag Location Method

电网短路故障是电压暂降的主要原因,准确定位暂降故障源的位置,不仅有利于供用电双方区分暂降责任,还可大幅缩短电力公司的故障清除时间,提高供电可靠性。提出一种基于多重判据的电压暂降故障源定位方法:从监测点布点入手,结合监测点可观测域和暂降源方位判断提取可能的故障线路;基于监测到的节点电压相量估计故障类型,在可能的故障线路上假设虚拟故障点,利用故障距离分布函数得到监测点电压计算值,根据计算值与测量值的误差分析结果定位暂降故障源。基于10节点和26节点网络的仿真,验证了所提方法的有效性和实用性。该方法可有效减少故障定位过程中的循环搜索过程,能够对伪故障点做出处理。

The main cause of voltage sag is short-circuit fault in power grid. Accurate positioning of voltage sag fault source locations can not only help distinguish responsibilities between power utilities and users, but also shorten fault clearing time and improve power supply reliability. A voltage sag fault source location method based on multiple criteria was proposed. The arrangement strategy of power quality monitors’ setting was carried out. Then the possible fault lines were identified based on the monitor observation range and voltage sag source locations. The fault type of possible fault line was identified according to the measured node’s voltage phasors. The voltage values at the monitoring nodes were calculated based on the distance distribution functions, which were determined by the virtual fault points on the possible fault lines. The possible ranking results of the virtual fault points were determined by the errors between the calculated and measured voltage values at the monitoring nodes. The efficiency and practicability of the proposed method were verified based on the simulations of 10-bus and 26-bus power grids. The proposed method can diminish the circulation searching process and identify the false fault points.