单位代码 10006 学 号 13988801812 分 类 号 TM1 密 级 毕业设计(论文)低压配电系统接地技术研究学习中心名称北航校本部专业名称电气工程及其自动化学生姓名张立辉指导教师周东朋2015年10月20日低压配电系统接地技术研究张立辉北京航空航天大学 独创性声明我在此郑重申明，本人所提交的毕业设计（论文），是在导师指导下由本人独立完成的研究成果，对文中所引用他人的成果，均已进行了明确标注或得到许可。毕业设计（论文）中不包含任何其他个人或集体已经发表或撰写过的研究成果，不包含他人已申请毕业证书（学位）或其他用途使用过的成果。对本文的研究做出重要贡献的个人和集体，均已在文中作了明确说明并表示了谢意。本人完全意识到本声明的法律结果，如有不实之处，由本人承担一切相关责任。学生签名： 张立辉 时 间： 2015年10月20日低压配电系统接地技术研究摘 要接地是电力系统中非常重要的一项工作，是电力系统中广泛采用的技术措施，涉及到电力系统能否正常工作与电气安全。然而在实际生产生活中，人们对接地制式及庞大的接地技术理解并不全面，在施工中经常出现不接地或乱接地的情况，给电力系统的安全运行埋下安全隐患。有鉴于此，本文试图对低压配电系统的接地制式、进行系统的归类、分析与比较，力图更加全面、准确、深刻地理解与应用接地技术，更好地保证电力系统的安全运行。研究接地技术首先就要搞清楚什么是接地，因此本文首先在绪论中叙述了接地的概念，并较为深入地叙述了工作接地和保护接地的概念、形式特点及保护原理与作用等。全文按照国际电工委员会(IEC)对低压配电系统接地制式的五种分类TN-C、TN-S、TN-C-S、TT、IT来展开论述，分别阐述了它们各自的接线形式、保护原理、保护线断线时的特征、各种接地制式的优缺点、以及它们各自的适用范围等。在TN系统综述中，本文详细阐述了重复接地的概念，本文更正了一些文献中关于重复接地的定义，从对配电系统的分析中得出：严格来说可以重复接地的从来不是N(零)线，它要么是N(零)和PE(地)合一的PEN线，要么就是单独的PE(地)线。因此本文采用了北京市工伤及职业危害预防中心编著的电工(低压运行维修)对重复接地的定义。本文通过深入分析与讨论五种低压配电系统接地制式，通过层层推理来得出结论，不同于一些电工工具书里的简单的、机械式的说教，使人们对得出的结论理解更加深刻全面，从而能够使电气相关人员活学活用到不同情况、不同条件的具体的配电系统建设中去。关键词：接地，TN-C，TN-S，TN-C-S，TT，ITSduty on Grounding Technique of the Low-voltage Distribution SystemAbstractGrounding is a very vital work in the power system and a technical measure widely used in the power system, concerning whether the power system could normally operate, as well as electrical safety. However, in the actual production and living, peoples understanding of grounding types and various grounding technique is not complete. Therefore, cases such as non-grounding or wrong grounding frequently occur in construction, which cause hidden dangers for the safe operation of the power system. Considering the above situations, this paper tries to conduct a systematic classification, analysis and comparison for the grounding types in the low-voltage distribution system, in order to understand and employ grounding technique more completely, more accurately and more deeply and to better guarantee the safe operation of the power system.Before studying grounding technique, it must figure out what grounding is, and therefore, in this paper, the concept of grounding is firstly expressed in the introduction part, and meanwhile, concepts, form characteristics, protection principles and effects, etc. of the working grounding and the protective grounding are deeply indicated. This paper arranges its contents according to the five grounding types, including TN-C, TN-S, TN-C-S, TT and IT, in the low-voltage distribution system classified by the International Electrotechnical Commission (IEC), which involve their respective grounding forms, protection principles, characteristics when the guard wire breaks, advantages, disadvantages and the scope of application.In the TN system summary, the concept of iterative grounding is narrated in detail in this paper and definition of the iterative grounding recorded in some other documents is also corrected in this paper. It can be got from the analysis of the distribution system that: strictly speaking, the iterative grounding shall never be selected for N (null) wire, which is applied to PEN wire that is the combination of N (null) wire and PE (ground) wire, or the independent PE (ground) wire. Therefore, definition of the iterative grounding adopted in this paper is from the Electrician (Low-voltage Operation and Maintenance) prepared by Beijing Occupational Injury and Occupational Hazard Prevention Center.Conclusions in this paper are made through deep analysis and discussion of five grounding types in the low-voltage distribution system and then layer-by-layer reasoning, which are different from simple and mechanical narration in several electrician reference books and therefore, peoples understanding of those conclusions are deeper and more complete. Meanwhile, the relevant electrical personnel could master it flexibly and apply to the specific distribution system engineering in different cases with different conditions.Key words: Grounding, TN-C, TN-S, TN-C-S, TT, IT目 录1 绪论51.1什么是接地（工作接地和安全接地）51.2低压配电系统的接地制式72 TN系统的形式及特点92.1 TN系统综述92.2 TN-C系统112.3 TN-S系统132.4 TN-C-S系统163 TT系统的形式及特点184 IT系统的形式及特点21结 论25致 谢27参考文献281 绪论电气接地是电气系统中非常重要的一项工作，涉及到电气系统能否正常工作与电气安全，然而在实际生产生活中，人们对庞大的接地技术理解并不全面，有些接地工作并未引起施工人员的重视，造成接地不良和乱接地的后果，给电力系统安全运行带来安全隐患，因此全面理解和认识接地技术就成为电气相关人员急需的必备知识。在整个配电系统中，低压配电系统深入厂矿、街道、居民区、楼宇内部、和广大的人民群众最为接近，因此低压配电系统的安全，关系到人民群众生命财产安全，低压配电系统的接地技术就成为整个配电系统的重中之重。1.1什么是接地（工作接地和安全接地）电气接地是一种应用广泛且古老的接地技术，无论高低压、还是交直流、强弱电都采用