接地方式对配电网接地故障影响分析

发布时间：2018-04-27 02:18

本文选题：配电网 + 接地故障　；参考：《华南理工大学》2014年硕士论文

【摘要】：电力系统的中性点接地方式通常是按电压等级的高低来进行选取的，当前我们国家电网通常采用的接地方式有：不接地、直接接地、经电阻接地和经消弧线圈接地。110kV及以上电网都采用中性点直接接地方式，而6～66kV配电网均采用中性点不直接接地方式，本文针对广东电网公司使用最多的10kV配电网来进行讨论。 10kV配电网中性点接地方式的选择是一个涉及到多方面技术理论的综合性问题，不仅包含电力技术，还包含了经济问题。电力系统在正常运行时，，对不同的中性点接地方式及其差异，系统基本不受影响。可是，当系统发生接地故障时，其特性受接地方式的影响很大。当前东莞地区变电站的10kV配电网接地方式主要有经消弧线圈和经小电阻接地两种。过去我们比较偏向于采用经消弧线圈接地的方式，但近年来由于电网发展和设备更新等原因，经消弧线圈接地方式的弊端日渐显露出来，我们在配电网接地方式的选择上面，又逐渐偏向于经小电阻接地的方式，尽管经小电阻接地的方式也是有其弊端。当前我们必须面对的情况是，在东莞市的配电网中，经消弧线圈接地和经小电阻接地这两种方式在未来很长的一段时间还是共存的。本文的主要工作是： 1、通过分析经消弧线圈接地系统和经小电阻接地系统的原理，对比两种接地系统在发生接地故障时的变化量特征，归纳两种不同接地方式的优缺点； 2、以东莞配电网为蓝本，根据配电网的网络架构、材料选用、保护整定、设备维护等方面因素，并结合一些事故案例，来分析经消弧线圈接地系统和经小电阻接地系统在实际运行过程中存在的问题； 3、通过逻辑推理以及现实状况，总结和归纳解决当前经消弧线圈接地系统和经小电阻接地系统存在问题的一些措施； 4、根据当前配电网的发展趋势，提出关于未来配电网中性点选择以及保护配置方面的一些看法。
[Abstract]:The neutral grounding mode of power system is usually selected according to the voltage level. At present, the normal grounding methods used in our national power grid are: no grounding, direct grounding, Direct neutral grounding is adopted in both resistance grounding and arc-suppression coil grounding and direct neutral grounding is adopted in 6~66kV distribution network. This paper discusses the 10kV distribution network which is widely used by Guangdong Power Grid Company. The selection of neutral grounding mode in 10kV distribution network is a comprehensive problem involving various technical theories, including not only power technology, but also economic problems. When the power system is in normal operation, the system will not be affected by different neutral grounding modes and their differences. However, when the grounding fault occurs, the characteristics of the system are greatly affected by the grounding mode. At present, there are two kinds of grounding modes of 10kV distribution network in Dongguan substation, which are arc suppression coil and small resistance grounding. In the past, we preferred to use the method of grounding through arc-suppression coil, but in recent years, due to the development of power network and the renewal of equipment, the malpractice of grounding through arc-suppression coil has been revealed day by day, so we are choosing the grounding mode of distribution network. And gradually favor the way of grounding through small resistance, although the way of grounding through small resistance has its drawbacks. At present, we must face the situation that in the distribution network of Dongguan City, the two ways of grounding through arc-suppression coil and through small resistance will coexist for a long time in the future. The main work of this paper is: 1. By analyzing the principle of arc-suppression coil grounding system and small resistance grounding system, the variation characteristics of two kinds of grounding systems are compared, and the advantages and disadvantages of two different grounding modes are summarized. 2. Take the Dongguan distribution network as the blueprint, according to the network structure of the distribution network, material selection, protection setting, equipment maintenance and so on, and combine with some accident cases, To analyze the problems existing in the actual operation of the grounding system through the arc-suppression coil and the grounding system through the small resistance; 3. Through logical reasoning and reality, the paper summarizes and summarizes some measures to solve the problems existing in the current grounding system via arc-suppression coil and through the grounding system with small resistance. 4. According to the development trend of distribution network at present, some views on the selection of neutral point and protection configuration of distribution network in the future are put forward.
【学位授予单位】：华南理工大学
【学位级别】：硕士
【学位授予年份】：2014
【分类号】：TM862

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