Results 11 to 20 of about 27,650 (147)
Driving of the Squirrel-cage Three Phase Induction Motor with Mc Murray-type Three-phase Inverter [PDF]
, 1968 The output wave form of Mc Murray type three phase inverter is rectangular and it involves many harmonics. The squirrel-cage three phase induction motor (750W, 200V, 50/60 c/s, 4 poles) was drived by the inverter, then efficiendes and temperature rises ...
岡田 粂ニ
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New development of the theories of nano-interfaces and their application to nano-devices [PDF]
, 2009 課題番号 ...
シライシ ケンジ, 白石 賢二
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Basic study on the current signals caused by one line grounding fault in distribution lines consisting of neutral system with grounding reactors [PDF]
, 1995 There is ground fault as one of the most impotant problems in distribution lines. It is urgently necessary to establish the technology to distinguish the causes of their faults for preventing them beforehand or finding their locations at the early stages.
北村 岩雄 +5 more
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ELUCIDATION OF CHARGE INTERACTIONS BETWEEN GRAPHENE AND QUANTUM DOTS [PDF]
, 2021 Graphene attracts attention for its novel physical properties, such as quantum electron transport, high carrier mobility, and high elasticity. However, graphene has low light absorption per layer, which limits its application to photodetectors.
井上 禅
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Dianci bileiqi, 2016 煤矿配电网变压器中性点一般对地绝缘,一旦发生雷击事故,将在中性点产很高的过电压而损坏变压器。因此对雷击下变压器中性点过电压表现特性及引入过电压保护设备后的限压效果研究具有非常大的实际意义。笔者针对山西煤矿集团万家庄煤业35 kV变电站主变中性点对地放电和母线短路故障,调研煤矿配电网防雷现状,结合雷电波过电压传播理论及35kV变压器中性点绝缘性能,分析中性点对地放电事故的原因。并提出线路绝缘子与可调保护间隙的绝缘匹配和、变压器中性点经氧化锌避雷器接地等改造措施。并利用电磁暂态分析程序ATP ...
扈海泽 +9 more
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A Kind of Large Load Light UAV Conceptual Design Platform and Manufacturing [PDF]
, 2016 近年来，无人机在军事领域的地位越来越重要；在民用领域，无人机的重要性也日益凸显。轻型无人机具有结构简单、体积较小、飞行高度低、飞行速度慢等特点，俗称“低小慢”航空器，可以利用较小的空间进行收放，起飞准备时间短，方便使用者利用有限的时间和空间进行工作。近几年来，随着飞控技术被不断重视，各方面科研力量都着手研制自己的飞控系统，同时各个拥有航空背景的高等学府也纷纷投入其中。作为高校，研制飞控系统需要有适合做飞行实验的飞行平台，此时，轻型无人机就可以发挥重要作用。因此 ...
黄荣
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Dianci bileiqi, 1998 变压器中性点保护用氧化锌避雷器的选择应根据不同电网中变压器中性点上可能出现的暂时过电压、变压器中性点的绝缘水平及避雷器的制造水平等综合考虑。本文阐述了变压器中性点保护用氧化锌避雷器的选择方法及变压器中性点保护用氧化锌避雷器制造技术的最新发展。
张西元
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Novel PWM Techniques and Topologies for Multi-Level Inverters [PDF]
, 2001 博士論文 (Doctoral dissertation)doctoral ...
406371, K. R. M. Nimal Ratnayake
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Gaoya dianqi, 2017 文中主要研究了1000 kV特高压交流输电工程中使用的中性点电抗器的绝缘特性。首先,通过工频过电压分析和特高压工程系统调试期间实测数据,仿真分析了中性点电抗器在冲击电压下的电位分布;接着提出了用于考核中性点电抗器匝间绝缘性能的现场耐压试验方法,并对中性点电抗器在试验中动热稳定性进行了计算及校核,理论论证了现场耐压试验的可行性和适用性;最后文中用于考核特高压中性点电抗器绝缘性能的试验方法在现场得到验证。文中提出的应用于特高压中性点电抗器的现场匝间绝缘考核的试验方案可以作为今后交接试验的参考。
李予全 +8 more
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Gaoya dianqi, 2009 笔者通过对几例大型变压器中性点绝缘故障实例的分析,说明了现场考核变压器中性点绝缘的必要性。文章还介绍了利用变压器中性点现场交流耐压试验以考核其绝缘的方法,并提出对变压器中性点进行局部放电测量的建议。
王伟 +4 more
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