共查询到20条相似文献,搜索用时 78 毫秒
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电气化铁路27.5 kV单相交流交联聚乙烯绝缘电缆的防水性能并不能完全满足实际环境。通过对结构进行改进,增加了LAP护套,设计出防水性能改善的新电缆。同时介绍了铜丝屏蔽的设计方法和电缆的生产工艺。 相似文献
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介绍了东北电网500kV输电线路雷击跳闸情况,分析了雷击跳闸的特点和工程设计中存在的主要问题,提出了防雷工作的具体方法。 相似文献
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介绍了电气化铁道27.5 kV单相铜芯交联聚乙烯(XLPE)绝缘电缆的结构、工艺和性能,并对产品的标准提出了一些建议。 相似文献
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简要介绍了单芯电缆金属护层接地的各种方式,对BATA电网20 kV单芯电缆金属护层接地方式进行了简单分析并进行了接地设计,包括单芯电缆金属护层感应电压计算。BATA市位于赤道几内亚共和国大陆(木尼河地区)西北部,西临大西洋,市区面积约95 km2。BATA原有配电电网相当薄弱,在2010年后该市电网进行了大面积的改建及新建。经改造升级后,该市中压配电网电压等级为20 kV,配电线路均采用单芯电缆线路。 相似文献
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本文根据电力系统运行统计资料,分析了雷击杆塔与地形和接地电阻的关系,还说明了《电力设备过电压保护设计技术规程》中的落雷密度“γ”取值太小,与实际不符,应重新修订。 相似文献
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Ryosuke Hatano Yasuhisa Ishikawa Toshiaki Ueda Kenichi Nojima Hideki Motoyama 《Electrical Engineering in Japan》2004,146(1):46-58
This paper describes the outline and results of the lightning impulse tests for a 275‐kV full GIS substation. The behavior of lightning surges is a very important factor for the rational design of substations and low‐voltage and control circuits inside the substations. For the above reason, we carried out lightning impulse tests for a new 275‐kV full GIS substation. In these tests, we measured voltage induced in low‐voltage and control circuits, transient characteristics of grounding grid, injected voltage and current waveforms, and so on. By investigating these data, we confirmed the behavior of lightning surges inside the substation. We also compared simulated waveforms by EMTP analysis with the measured waveforms. The simulated results agreed well with the measured results. © 2003 Wiley Periodicals, Inc. Electr Eng Jpn, 146(1): 46–58, 2004; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/eej.10230 相似文献
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为考虑雷击架空输电线路后,雷电流在避雷线、杆塔、接地网和土壤中的动态散流过程,建立了输电线路-杆塔-接地网一体化雷电全波电磁暂态模型,计算冲击接地电阻和反击过电压。基于全波电磁暂态模型,从冲击接地的概念出发,将土壤电阻率、雷电流波前时间和幅值对输电线路的影响直接反映在雷电过电压上,对雷电过电压与冲击接地电阻计算公式进行拟合。研究表明:波前时间减小和土壤电阻率增大均会使冲击接地电阻值与雷电过电压增大。不考虑火花效应时的冲击接地电阻值与雷电流幅值无关,雷电过电压随雷电流呈正比例增大。在进行接地网设计时,应考虑能使雷电过电压值下降的接地网射线的有效长度。 相似文献
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针对某矿区35 kV架空线路4号-8号杆塔之间线路易受雷击、杆塔接地电阻值超标的问题,通过对雷电流、架空线以及避雷器进行建模,对杆塔和绝缘子进行选型,确定了架空线阻抗、绝缘子串50%闪络电压、雷电波通道阻抗等参数,运用电磁暂态分析工具ATP对该端架空线路的耐雷水平进行仿真分析,定量分析了未装设避雷器情况下接地电阻改善前后杆塔的耐雷水平,在此基础上对该线路段装设避雷器的组数和安装位置进行仿真分析,结果为在4号-8号杆塔之间的5号和6号杆塔安装两种避雷器能最大程度地提高耐雷水平. 相似文献
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关于1kV级五芯电力电缆开发的意见 总被引:3,自引:3,他引:0
综述目前国内生产 1k V五芯电力电缆的概况 ,介绍了国外的生产设备和工艺 ,并对铜、铝、钢三种材料作为 1k V五芯电力电缆的保护层作了经济分析 相似文献
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Hideki Motoyama 《Electrical Engineering in Japan》2008,164(3):35-41
Lightning surge analysis is very important from the viewpoint of insulation design of transmission lines and substations. Lightning surge analysis has many parameters, which include lightning surge characteristics of transmission towers, back flashover phenomena at an arcing horn, characteristics of footing resistance, effects of corona wave deformation, characteristics of electromagnetic fields caused by lightning, and other parameters. This paper describes experimental and analytical studies on lightning surge characteristics of a buried bare wire. The measurement of the lightning surge characteristics of the buried bare wire is carried out under various experimental conditions. The experimental parameters controlled in these experiments include earth resistance, length of the buried bare wire, and waveform of the injected current. The measured results are compared with analytical results based on the theoretical study by Sunde. A comparison of the measured results with the analytical results shows good agreement. © 2008 Wiley Periodicals, Inc. Electr Eng Jpn, 164(3): 35– 41, 2008; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/eej.20532 相似文献
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Hideki Motoyama 《Electrical Engineering in Japan》2007,160(4):16-23
Lightning surge characteristics of a ground mesh have an influence on electromagnetic transient behaviors in low‐voltage and control circuits. This paper describes experimental and analytical studies on lightning surge characteristics of a ground mesh. The experimental studies are carried out under various conditions. The experimental parameters considered in this measurement include earth resistances, current injection points, and injection current waveforms. These measured results are compared with calculated results based on the theoretical studies by Sunde. A comparison of the measured results with the calculated results shows good agreement. © 2007 Wiley Periodicals, Inc. Electr Eng Jpn, 160(4): 16– 23, 2007; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/eej.20559 相似文献
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750 kV输变电示范工程单相人工接地故障试验现场实测和计算分析 总被引:3,自引:1,他引:3
应用电磁暂态计算程序(electromagnetictransientprogram,EMTP)对安装金属氧化物避雷器的35kV配电线路的耐雷水平进行了分析计算。具体比较了雷击有、无避雷线的线路,采取不同避雷器安装方案时的耐雷水平;分析了杆塔冲击接地电阻、绕击导线位置对耐雷水平的影响。仿真计算结果表明,安装线路避雷器﹑减小杆塔的接地电阻可有效提高35kV配电线路的耐雷水平。对于35kV有避雷线配电线路,加装线路避雷器后可显著降低其发生绕击闪络的概率。 相似文献
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20 kV配电网中性点接地方式选择的研究 总被引:3,自引:1,他引:2
20 kV配电网中性点接地方式的选择是重要的技术问题.在对中性点不接地、经消弧线圈接地和小电阻接地这三种配电网中性点接地方式进行分析和研究的基础上,给出了不同网络结构20 kV配电网中性点接地方式的选择方案.对不同中性点接地方式对安全性、供电连续性,以及对配电网的设备改造的经济性进行了比较分析,为20 kV改造中对配电网中性点接地方式选择和相关设备的选择提供依据和参考. 相似文献