摘要
摘要
分布式发电作为一种新兴的发电技术，以其高效、环保的特点在近几年获得了飞速的发展。然而，分布式电源(Distributed Generation，DG)接入配电网以后，原来简单的单电源辐射网络变为了复杂的多电源网络，导致原有配电网馈线保护出现灵敏度降低、拒动、误动等问题，由此给配电网的运行和控制带来多方面的影响，因此研究分布式电源的引入对配电网保护所带来的影响及提出相应的对策是十分必要的，对于分布式电源的发展和推广有着重要的意义。
本文简单介绍了研究课题的背景、发展现状和研究目标，并从DG的容量、类型、位置等因素出发，对配电网馈线保护可能产生的影响进行了定性分析，通过MATLAB仿真软件实现了对建立模型的仿真，验证了定性分析的结果。此外，针对现有的配网保护提出了改进方案，主要是加装方向元件、修改定值或采用纵联差动保护等。
关键词 分布式电源；配电网；继电保护；馈线自动化；MATLAB仿真；整
定原则
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Abstract
Abstract
The Distributed Generation technology is predicted to play an increasing role in power system of the near future in the light of its character of high efficiency, environmental．However, with the interconnection of distributed generation (DG)，the distribution system has developed from the traditional simple single-source radial-network to complicated multi-source loop-network，bringing traditional feeder protection new problems in distribution network,such as sensitivity decrease，misoperation and malfunction，which deeply affects system operating and controlling．Therefore it is necessary to analyze the influence of the DG to the distribution network protection and propose its countermeasures，which is very useful to the development and practicality，for the distributed generation technology．
This paper explains the background，the research progresses and research aims，discusses that different capacity type and location of the DG source have different impacts on the current flowing through the feeder protection in distribution network．Also,the MATLAB simulation of the model confirms that the results of qualitative analysis are true．In addition, improvement schemes are proposed in tlle light of the existing distribution protection，mainly including installing the direction element，modifying the setting value and using the longitudinal differential protection．
Keywords distributed generation(DG)，distribution network, relay protection,
feeder automation，MATLAB simulation ,setting principles
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目 录
摘要 ....................................................................................................................... I Abstract ................................................................................................................ II 第1章 绪论 ........................................................................................................ 1
1.1 课题背景 .............................................................................................. 1 1.2 课题研究的目的和意义 ...................................................................... 3 1.3 国内外研究现状 .................................................................................. 4 1.3.1分布式发电技术国内外研究现状 ............................................... 4 1.3.2 含DG配电网保护的研究现状 .................................................... 6 1.4 论文的主要工作 .................................................................................. 6 第2章 分布式电源技术 .................................................................................... 8
2.1分布式发电的概念 ............................................................................... 8 2.2分布式电源的分类 ............................................................................... 8 2.2.1燃料电池 ....................................................................................... 9 2.2.2微型燃气轮机 ............................................................................... 9 2.2.3风力发电技术 ............................................................................. 10 2.2.4太阳能光伏电池 .......................................................................... 11 2.3本章小节 ............................................................................................. 12 第3章 分布式电源对配电网保护的影响 ...................................................... 13
3.1 引言 .................................................................................................... 13 3.1.1分布式电源的类型及容量对配电网保护的影响 ..................... 14
3.1.2分布式电源的不同接入点对配电网保护的影响 ..................... 15 3.1.3分布式电源对配网自动装置的影响 ......................................... 17 3.2算例分析 ............................................................................................. 18 3.2.1模型参数的选择 ......................................................................... 18 3.2.2 MATLAB仿真软件介绍 ............................................................... 20 3.2.3仿真系统模型 ............................................................................. 21 3.2.4仿真验证 ..................................................................................... 22 3.3本章小节 ............................................................................................. 29
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第4章 改进后的配网保护方案 ....................................................................... 30
4.1配电网现有保护配置的介绍 .............................................................. 30 4.1.1电流速断保护 .............................................................................. 30 4.1.2限时电流速断保护 ...................................................................... 31 4.1.3定时限过电流保护 ...................................................................... 32 4.2对现有馈线保护的改进方案 .............................................................. 32 4.3本章小节 .............................................................................................. 33 结论 ..................................................................................................................... 34 参考文献 ............................................................................................................. 35 致谢 ..................................................................................................................... 37 附录1 .................................................................................................................. 38 附录2 .................................................................................................................. 43 附录3 .................................................................................................................. 48 附录4 .................................................................................................................. 51 附录5 .................................................................................................................. 56
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