Results 41 to 50 of about 1,349 (142)
多片MOV并联型避雷器在10/350μs波形冲击实验过程中的性能参数变化
Dianci bileiqi, 2017 采用了20 kV多波形发生器、红外温枪,相关性分析等实验方法研究了多片MOV并联型避雷器在10/350μs波形冲击实验过程中的性能参数变化。实验表明:在10/350μs波形冲击破坏过程中,电荷Q和单位能量W/R存在显著的正相关性关系;10/350μs波形的冲击会导致MOV自身的阻抗发生变化,从而使多片MOV并联型避雷器中的各MOV产生温度差;用新的MOV替换损毁的MOV接入并联体可以使得避雷器重新恢复保护效能,但无法保证其使用寿命。
张家祥, 索娜
doaj
Gaoya dianqi船用断路器是舰船电力系统中的重要基础器件，其在动力学冲击载荷作用下的性能将直接关系到整个舰船电力系统的安全。为了研究影响断路器抗冲击性能的因素，文中建立了断路器模型，运用动力学设计分析法（DDAM）和时域分析法进行仿真研究。针对结构强度不足的现象，进行了优化设计，并通过冲击试验来予以验证。所得结论和方法对进一步提高断路器抗冲击性能提供了参考。
于庆瑞 +5 more
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Research and practice on key technologies for coordinated green mining of shallowly buried multi-coal seam groups [PDF]
The multi-seam occurrence conditions in the western mining area have brought forth prominent and common issues such as "contradictions in mining face layout, variable overburden structure, and superimposed surface migration".
Desheng ZHANG +5 more
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Dianci bileiqi, 2012 为了研究接地网在雷击时冲击接地阻抗的特性,提出了一种型等值电路,在考虑火花效应的条件下,运用ATP-EMTP仿真软件对接地网进行分析计算。将土壤电阻率以内分为四个区间,每个区间对应一个地网有效面积值。并运用多项式回归分析软件得出相应区间的冲击接地阻抗拟合公式,能方便计算不同条件下冲击接地阻抗的最小值。为防雷接地工程计算提供参考依据。
柴健, 杨仲江, 孙京
doaj
Calculation of slope stability of fault-containing slopes under the action of cyclic blast vibration [PDF]
In order to accurately quantify and predict the evolution of slope stability of fault-containing slopes under the long-term effect of blasting vibration, and to realize the safe, efficient and sustainable mining of open-pit mines. Taking an open-pit mine
Dong WANG +3 more
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Research progress of support theory and technology of the roadway surrounding rock based on the plastic zone control [PDF]
With the increasing depth of coal mining, the stability control of surrounding rock in deep roadway has become one of major problems in the mining field, and the effect of surrounding rock control in deep roadway is directly related to the safe ...
Lei FAN +3 more
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Key technology and equipment for fully mechanized mining with extra-large shearing height of 10 m in extra-thick coal seam [PDF]
Fully mechanized mining technology with extra-large shearing height is the optimal technical approach to achieve high-yield, high-efficiency and high-recovery mining for 6−10 m ultra-thick coal seam in Chinese coal mines.
Cundi HAN +17 more
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Gaoya dianqi, 2013 笔者提出的基于冲击电流的GIS导电杆的回路电阻测量方法,利用超级电容器与标准电阻和被测元件构成的非振荡二阶电路,能产生千安级的冲击放电电流;取冲击电流峰值时刻的导电杆电压降和峰值电流,求得GIS导电杆的回路电阻,以消除被测GIS导电杆感抗对测量结果的影响。笔者通过仿真计算、实验室测试验证了方法的可行性和准确性。现场测试中冲击电流法和直流压降法的测试结果对比显示,基于冲击电流的GIS导电杆的回路电阻的测量方法的更能反映设备实际的回路电阻值。
罗容波 +5 more
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Research progress on dynamic response of deep rocks under coupled hydraulic-mechanical loading [PDF]
Deep rock is under a complex geological environment with high geo-stress, high osmotic pressure, and strong dynamic disturbance, under the action of the three, the rock body is more prone to damage and rupture, inducing sudden water surges, seepage ...
Bangbiao WU +4 more
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