【作者】 唐群纲；

【导师】 林景栋；

【作者基本信息】 重庆大学 ， 检测技术与自动化装置， 2007， 硕士

【摘要】 配电自动化是电力系统发展的必然趋势,具有很强的工程应用背景和巨大的市场潜力。配电网的故障定位和网络重构是配电自动化的关键功能,也是目前国内外研究的热点。无论采用何种算法,配电网的故障定位及网络重构功能的实现均离不开配电网的拓扑结构,一个好的拓扑描述模型将有助于这些功能的实现。本文在分析传统电网络模型的基础上,充分挖掘配电网拓扑结构的特点,并结合图的概念,将配电网的开关看成顶点,将馈线看成边(或弧),从而将配电网抽象为图。为了提高供电的可靠性,当配电网出现故障时,必须快速确定故障区段。由于T接点的存在,使得配电网的故障定位比较麻烦。本文特别分析了包含T接点配电网的故障定位算法。由于T接点既不可测也不可控,其所形成的区域与其他非区域部分的故障判据不同,本文提出了将配电网的拓扑模型分解为只含区域部分和不含区域部分的描述模式,有效地解决了T接点对故障定位算法的影响。该算法简洁、清晰、有效。但随着配电网规模的扩大,配电网的顶点数量急剧增加,配电网故障定位功能实现的实时性日益突出,本文提出首先根据配电网的结构特点和FTU上报的信息生成一个包含了节点邻接方式及各节点的故障信息N×4价的故障电流判断矩阵D,然后把故障电流判断矩阵D分解成若干个4×4价单元方阵。利用搜索思想对每个单元矩阵进行搜索故障区域。针对各种配电网的故障快速定位非常适用。配电网一般具有闭环设计,开环运行的特点,这使得配电网可以重构。配电网网络重构的目标多种多样。在启发式搜索和前推回代的配电网潮流计算方法的基础上以系统网损最小为目标函数来优化配网结构是本文的中心。首先生成一个1×N阶描述配电网开关通断的矩阵,然后以网损不能再减少为目的对所有的联络开关进行搜索,而寻找全局最优解。随着配电网源点数量的增加,配电网负荷最优均衡算法的复杂度大为提高,加剧了网络重构算法的实时性矛盾。配电网网络重构的解是一组开关的组合,即配电网的负荷最优均衡的结果其实就是将一个配电网分割成几个子网络,各子网络之间通过分段开关连接,因此可以将配电网的负荷最优均衡问题作为网络优化的一个内容。基于此,本文提出了一种基于改进的遗传算法的在配电网重构中的应用,在算法中使用可操作开关支路的整数编号的排列顺序来表示染色体,并通过译码器的设计来映射染色体所对应的辐射状网络结构,避免了产生不可行解的情况,大大提高了算法的运算效率。同时在算法中引入了局部寻优算子,改善了算法的局部寻优性能。更多还原

【Abstract】 As a result of the development of power systems, the distribution automation system has great application background and tremendous marketable value. The fault section location and the reconfiguration are key functions of the distribution automation system, so they are become of the research direction for a lot of people in the world. However, the efficiency and accuracy of algorithms of fault section location and reconfiguration are related to the topology model for distribution networks. On the base of analysis of traditional models and features for distribution networks, this paper presents a model---- regarding the distribution network as a graphic.Owning to the mutual couplings of distribution networks, it is hard to realize the function of fault section diagnosis. An algorithm of fault section location based on topology identification for distribution networks is presented, by decomposing the topologic matrix which describing the distribution network into two parts which one part only contains the complex coupling factor and the other ignores the complex coupling factor. Using this method, the fault zones in distribution network can be identified and isolated efficiently, and the vertexes of the zones can also be identified automatically.Along with enlargement of scope of distribution networks, the algorithm of fault section location for distribution networks becomes an optimization problem in real-time operation environment. According to these request,first, this text according to structure of distribution networks and information of FTU, create fault electric current judgment N×4 matrix D that included the node abutment method and each node of the fault information, than break down the fault electric current judgment N×4 matrix D to some 4×4 phalanx units. Searching each matrix unit gain the fault district in the searched thought. The algorithm apply very much to various fault that aim to distribution networks.Reconfiguration of distribution networks, which is a key function of distribution automation system, is an important guarantee to enhance reliability of power supply and flexibility of power operating condition. Objects of reconfiguration for Distribution networks are multifarious. Center of this article is distribution network optimization that it take least system network loss as the objective function based on heuristic search and forward/backward sweep method power flow algorithm. First, according to structure of distribution networks and information of switch create an 1×N matrix, than search all of tie switch in the light of network loss cannot again reduce. It seek overall and optimal solution.Along with enlargement of scale of distribution networks and increment of numbers of regions and complex coupling nodes, the algorithms become difficult to satisfy real-time requirement of practical applications, especially for the restoration of distribution networks.In fact, reconfiguration of distribution networks is just as partition distribution networks into some sub-networks by switches whose position is open. Therefore reconfiguration of distribution networks can be comprehended as partitioning of distribution networks. On the basis of above comprehension, this paper provides a new algorithm---- genetic algorithm. This paper proposes an improved solution for distribution network reconfiguration based on a refined genetic algorithm. In the algorithm, the“the integer permutation”encoding is adopted with each integer representing one controllable switch. A decoder is designed to decide the final network configuration corresponding every chromosome. A local search operator is combined with the genetic algorithm which improves the local optimal capability of the algorithm.更多还原