基于差动有功功率和分区加权匹配的广域后备保护研究

发布时间：2018-02-06 05:48

本文关键词： 广域后备保护故障线路识别差动有功功率分区加权故障匹配　出处：《西南交通大学》2017年硕士论文　论文类型：学位论文

【摘要】：电力系统规模的日益扩大,电网互联性的增强,传统后备保护在保护的整定、配合等方面存在很多困难,由于只使用本地测量信息,无法随着电力系统的变化发挥出最好的效果。而随着广域量测技术的推广应用,利用广域范围内的信息准确识别故障,保证电网的安全,这不失为一种很好的途径,再加上广域后备保护整定较简单,且不需要时间的配合,因此受到越来越多专家学者的关注。本文先对广域后备保护系统的结构做了简介,概述了现有广域后备保护算法的原理。对已有算法在受电容电流、负荷电流、过渡电阻影响表现不佳的情况及在传统保护启动信号出错位数较多时算法的容错性问题,进行了分析。本文研究了一种基于差动有功功率的广域后备保护算法,采用间隔母线布点策略在全网安装有限个PMU,将大电网划分为若干个保护区域,计算各区域的正序差动有功功率,与阈值比较从而判别故障区域。在故障区域内,先由各推算电压幅值的大小识别故障线路,当各推算电压的幅值很接近时,计算故障区域内每条线路的差动有功功率,并分析了故障线路与正常线路差动有功功率的差异,从而构造判据进行故障线路识别。在IEEE39节点测试系统中的多组仿真实验验证了本算法在各种类型故障时都能判别故障线路,不受线路分布电容、负荷的影响,且在过渡电阻达到300Ω时仍能准确识别故障线路。本文研究了一种基于分区加权匹配的广域后备保护算法。将线路按照传统保护的整定范围模糊的划分为5个区段,利用几类传统保护的广域冗余信息,构造了线路的实际保护向量与各区段故障期望保护向量,定义了分区加权故障匹配函数,给出了广域后备保护算法的故障判据与流程。采用穷举法进行仿真实验,仿真结果表明,本文算法能够在5位保护信息出错情况下保证故障检测的100%正确率,通过仿真分析了广域保护元件的选择及其权重系数、电网拓扑结构及其变化等因素对本算法容错性的影响。
[Abstract]:With the increasing scale of power system and the enhancement of interconnection of power network, there are many difficulties in setting and matching of protection for traditional backup protection, because only local measurement information is used. With the popularization and application of wide area measurement technology, the wide area information can be used to identify the fault accurately to ensure the security of the power network. This is a good way, plus wide area backup protection setting is relatively simple, and do not need time to cooperate. Therefore, more and more experts and scholars pay attention to it. Firstly, the structure of wide area backup protection system is introduced, and the principle of existing wide area backup protection algorithm is summarized. The effect of transition resistance on the poor performance and the fault tolerance of the traditional protection start signal with a large number of error bits are analyzed. A wide area backup protection algorithm based on differential active power is studied in this paper. A limited number of PMUs are installed in the whole network by using the spacer bus placement strategy. The large power grid is divided into several protection areas, and the positive sequence differential active power power is calculated in each region. In the fault area, fault lines are identified by the magnitude of the calculated voltage amplitude, when the amplitudes of the calculated voltages are very close. The differential active power of each line in the fault area is calculated, and the difference of the differential active power between the fault line and the normal line is analyzed. In order to construct a criterion for fault line identification, a number of simulation experiments in the IEEE39 node test system show that the algorithm can identify the fault lines without the line distributed capacitance in all kinds of faults. The impact of load. And the fault line can be accurately identified when the transition resistance reaches 300 惟. In this paper, a wide area backup protection algorithm based on zonal weighted matching is studied. The line is divided into 5 fuzzy parts according to the tuning range of traditional protection. Section. Using several kinds of wide-area redundant information of traditional protection, the actual protection vector and the expected fault protection vector of each section are constructed, and the partition weighted fault matching function is defined. The fault criterion and flow chart of wide area backup protection algorithm are given, and the simulation results show that the exhaustive method is used in the simulation experiment. This algorithm can guarantee the 100% correct rate of fault detection in the case of 5-bit protection information error. The selection of wide-area protection elements and their weight coefficients are analyzed by simulation. The influence of network topology and its variation on the fault tolerance of this algorithm.
【学位授予单位】：西南交通大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：TM77

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