含DG的配电网故障定位及微电网接地方式研究

发布时间：2018-06-22 12:09

  本文选题：配电网 + 分布式电源　； 参考：《太原理工大学》2014年硕士论文

【摘要】：随着全球能源问题的逐渐凸显,使用清洁、低耗、可再生能源成为全世界共同的追求。分布式电源,如光伏、风机、蓄电池等近年来得到广泛重视,其可直接接入配电网中给用户供电。但与此同时分布式电源的接入改变了配电网的结构,配电网原来的故障定位方法不再适用。因此,研究新的适合于含分布式电源(Distributed Generation, DG)的配电网故障定位方法对于提高用户供电可靠性和广泛使用DG具有深远意义。另外,为了充分发挥DG的优势及减小其对配网造成的不利影响,有学者提出了微电网的概念,目前大多数研究集中于微电网的运行与控制,对微电网的系统接地方式及安全性少有研究。 本文研究内容如下。 (1)DG的接入改变了配电网的节点类型,使得原有配电网的故障定位方法不再适用。本文分析了DG接入配电网后对原有故障定位算法的影响,分析了含DG的配电网节点类型,提出了故障定位实用化判据,并通过具体的含DG的配电网进行了仿真,验证了该判据实用有效。 (2)介绍了目前配电网故障定位通用矩阵算法的原理,提出了基于改进矩阵算法的含DG配电网故障定位法。该方法将馈线终端单元(Feeder Terminal Unit, FTU)测得的故障信息和配网SCADA系统信息相结合并通过故障定位算法隔离故障区域,恢复非故障区域的正常供电。该方法无需进行矩阵相乘,定位原理简单、直观,对多分支母线节点测量环节工作异常无法判断故障方向有一定的适应性。 (3)针对实际配电网馈线上一般不装设电压互感器TV的情况,提出了基于分布决策的含DG的配电网故障定位法。此方法利用智能电子装置(Intelligent Electronic Device, IED)交换信息和关联区域状态函数F(A)及区段状态函数G(i,j)定位故障。本文还介绍了F(A)和G(i,j)的计算方法、IED关联区域静态划分、动态修整法。此方法具有无需借助于电压量测量的优点,能够很好地用于含DG配电网的故障定位。 (4)利用配电网广域范围的电流量信息,提出了不需要借助方向信息的含DG配电网故障定位方法,即利用电流Ⅱ段保护的动作信息对发生在DG上游区域的故障进行定位,利用电流Ⅲ段保护的动作信息对发生在DG下游区域的故障进行定位,快速切除故障。本方案在故障定位时无需借助于电压量测量,且不需改变配网原有电流Ⅱ段及Ⅲ段保护整定值,减小了整定工作量。 (5)研究了微电网的系统接地方式。微电网孤岛运行时,微电源受到电力电子开关装置的限制,无法提供很大的故障电流。本文提出采用蓄电池储能装置来提供更大的故障电流,设计了微电网中变压器的接地网。经仿真分析,在故障条件下,变压器内外部实际接触电压和跨步电压都未超过二者的安全阈值,证明了所设计接地网满足安全性要求。
[Abstract]:With the global energy problem gradually prominent, the use of clean, low consumption, renewable energy has become the common pursuit of the world. Distributed power generation, such as photovoltaic, fan, battery and so on, has been paid more and more attention in recent years, and it can be directly connected to the distribution network to supply power to users. But at the same time, the access of distributed generation has changed the structure of distribution network, the original fault location method of distribution network is no longer applicable. Therefore, it is of great significance to study a new fault location method with distributed generation (DG) for improving the reliability of power supply and widely using DG. In addition, in order to give full play to the advantages of DG and reduce its adverse influence on distribution network, some scholars have put forward the concept of microgrid. At present, most of the research focuses on the operation and control of microgrid. There is little research on the grounding mode and safety of microgrid system. The main contents of this paper are as follows: (1) the access of DG changes the type of nodes in the distribution network and makes the fault location method of the original distribution network no longer applicable. This paper analyzes the influence of DG on the original fault location algorithm, analyzes the type of distribution network node with DG, puts forward the practical criterion of fault location, and simulates the distribution network with DG. It is proved that the criterion is practical and effective. (2) the principle of current universal matrix algorithm for distribution network fault location is introduced, and a fault location method with DG based on improved matrix algorithm is proposed. This method combines the fault information measured by Feeder Terminal Unit (FTU) and SCADA system information of distribution network. The fault area is isolated by fault location algorithm, and the normal power supply in non-fault area is restored. The method does not need matrix multiplication, and the positioning principle is simple and intuitionistic. It has some adaptability to the abnormal work of multi-branch busbar node. (3) aiming at the situation that voltage transformer TV is not generally installed on the feeder line of actual distribution network, A DG based fault location method for distribution network based on distributed decision is proposed. This method uses Intelligent Electronic device (IED) to exchange information and correlate region state function F (A) and segment state function G (ij) to locate faults. This paper also introduces the calculation methods of F (A) and G (ij). This method has the advantages of no need of voltage measurement, and can be used in fault location of distribution network with DG well. (4) the wide area current information of distribution network is used. In this paper, a fault location method containing DG distribution network without direction information is proposed, that is, fault location occurs in the upstream region of DG using the action information of current section 鈪，

本文编号：2052785