基于数学形态学的高压直流输电故障测距  

Based on Mathematical Morphology of High-voltage DC Transmission Fault Location

作　　者：李忠柏 黄玉东[1] 韩刚[1] 

机构地区：[1]沈阳工程学院电力学院,沈阳110136

出　　处：《控制工程》2016年第4期592-596,共5页Control Engineering of China

基　　金：辽宁省博士启动基金(20141071)

摘　　要：柔性直流输电系统的容性及感性装置,使得行波的暂态量提取困难。采用行波波头衰减和畸变现象严重的电缆线路作为输电线路,由于行波色散严重,导致行波波头到达时刻的精确时间更为困难。故障发生时刻在输电线路2/3左右处就无法准确进行的提取,因此单端行波测距在距离远时无法测距。提出一种基于双端故障信息的单端测距法,当故障距离在中点之前,用M端故障量进行测距,当故障距离超过中点,用N端故障信息进行测距。采用数学形态学进行滤波,再用形态学梯度法进行故障发生时刻的提取。如何分辨故障距离是难点,总结故障的规律,最终获得计算故障距离的方法。采用PACAD/EMTDC进行建模仿真。该方法测距原理简单,设备投入少,准确度较高。The capacitive and inductive device of the flexible HVDC system makes it difficult to extract the transient characteristics of the traveling wave. The cable line, whose inceptive traveling wave has severe distortion and attenuation, is used as a transmission line, which makes the acquisition of the precise arrival time of the inceptive traveling wave increasingly difficult. The extraction course cannot be achieved at the length of about 2/3 of a transmission line when the fault occurs, therefore, the range measurement of the single ended traveling wave cannot be accomplished as the distance is far. In this paper, a single ended fault location method based on double-end fault information is proposed. When the fault distance is before the midpoint of the line, the fault distance is measured by the fault information at M end; when the fault distance is after the midpoint of the line, the fault distance is measured by the fault information at N end. The mathematical morphology is used for the filtering process, and then the morphological gradient method is adopted to extract the fault occurrence time. How to find out the fault distance is a challenging issue. As the failure rules are summarized, the method of fault distance calculation can be obtained. The modeling and simulation course is done by using PACAD/EMTDC. Experimental results show that the proposed method has a series of advantages with features of simple principle, low investment and high accuracy.

关 键 词：VSC-HVDC 电缆 数学形态学 形态学梯度 

分 类 号：TM721.1[电气工程—电力系统及自动化]