针对现有直流线路时域故障定位算法采用精确线路模型以及固定数据窗存在的不足,提出一种基于异常点剔除的时域故障定位算法。该算法依据在故障点处从两端计算得到的沿线电压分布具有差值最小的特点,充分利用故障后的暂态数据,采用冗余数据窗移动,通过故障定位函数测量得到多个定位结果,将得到的多个定位结果作为数据集,采用统计学中的基于距离的异常数据处理方法将数据集中的异常数据剔除,进而得到最终的定位结果。基于PSCAD/EM TDC搭建云南—广东±800 k V双极直流输电系统模型对所提算法进行了验证分析,结果表明所提算法实现原理简单,在直流线路全长范围内能实现准确故障定位,充分利用故障后的暂态数据,有效地提高了故障定位精度和可靠性。
Aiming at the problem that the existing time-domain fault location algorithms used precise line model and fixed data w indow,this paper proposed a time-domain fault location algorithm based on picking out outliers. According to the characteristic that the voltage distributions obtained at both ends had minimum difference at the fault point,the proposed algorithm made full use of the post-fault transient data,and obtained the fault positioning results through fault location function w hen translating the redundant data w indow. Taking the positioning results as dataset,the distanced-based method in statistics w as adopted to pick out the outliers of the dataset,thus the final fault location result could be obtained. The Yunnan-Guangdong ± 800 k V bipolar DC transmission system model w as established in PSCAD / EM TDC to verify the proposed algorithm. The results show that the proposed algorithm is simple in principle,can realize accurate fault location w ithin the scope of w hole length of line,make full use of post-fault transient data,and effectively improve the accuracy and reliability of fault location.