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介绍了浙江电网合成绝缘子10年来的使用和运行情况,根据统计结果,详细分析了浙江电网合成绝缘子雷击闪络、不明原因闪络、内绝缘击穿以及芯棒断裂等故障的原因,针对各种故障原因,提出了相应的反事故措施和建议. 相似文献
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分析了照明装置的火灾原因及预防措施。包括白炽灯、荧光灯、高压汞灯及卤钨灯等常用照明灯具火灾的危险性,照明装置火灾的形成原因,以及相关的防火防爆措施等。 相似文献
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针对10kV架空绝缘导线运行中常见的问题,从设计方面分析了防雷措施不足、线路金具选用不当、档距过大等原因,并提出了对策。从施工方面分析了施工机具不当、施工操作对绝缘破坏严重等原因,提出解决的措施。 相似文献
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对一起因等电位屏蔽线接线不规范、安装工艺粗糙等原因造成的10 kV开关柜跳闸事件进行了充分的分析,找到事件的原因并对后期整改提出相应的对策. 相似文献
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南方电网近年来的功率振荡事件分析 总被引:1,自引:1,他引:0
总结了2008年以来南方电网发生的功率振荡,对这些振荡的原因进行归类,并就每类振荡原因进行实例分析.研究表明,近期南方电网功率振荡主要由地区小机组群弱阻尼振荡、调速系统和一次调频不稳定、励磁系统和 PSS 缺陷等原因引起,并针对这些原因提出了治理的思路. 相似文献
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李德超 《电力电容器与无功补偿》2014,35(6):86-90
对干式空心电抗器的结构特点进行了介绍,对干式空心电抗器常见故障原因加以分析,对温升影响、沿面树状放电、匝间短路等几个方面进行了着重研究;并根据故障原因,对各类故障防范措施进行了探讨,从设计、材料选择、制作工艺、运行维护管理等方面给出了一些针对性建议。 相似文献
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本文证明了系统去耦的充要条件;提出了系统去耦的一般方法——模态分析法。此外还引进现代计算机解法(广义雅可比法),编制了计算程序,可在IBM—PC 机上运行。 相似文献
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以岩石电参数测量为背景,根据岩石材料的电性特点,对谐振腔法测试电参数进行了比较详细的研究.利用仿真软件设计并改进了常规谐振腔的结构,设计了一种小型化和有效的测量仪器,以方便携带和使用.然后,利用微扰法和建立等效电路模型对谐振腔进行建模,推导出电参数和谐振腔参数直接的关系,再通过拟合的办法得到关系式的参数信息.对模型进行仿真测试,比较了等效电路模型和微扰法的精度,可以看出等效电路模型的测量误差小于5%.最后搭建了测试系统,对一些材料进行测试,得到了满足测试要求的结果,并分析了测量系统的不足以及改进方法. 相似文献
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Pontiga F. Castellanos A. 《Dielectrics and Electrical Insulation, IEEE Transactions on》1997,4(2):224-237
The conduction of a nonpolar liquid filling a cylindrical capacitor has been investigated with a model that includes both the dissociation of ionic pairs in the bulk of the liquid and charge injection at the inner electrode. Three different cases, of increasing complexity, have been analyzed. Firstly, injection has been neglected and the dissociation rate has been taken as constant. Then, the effect of the electric field on the dissociation rate has been considered. And, finally, a field dependent injection of charge has been also included in the model. The current voltage characteristics corresponding to these three models have been evaluated for different ratios of the electrodes radii. Approximate analytical expressions are provided for the charge density and electric field distributions over a wide range of parameters of physical interest 相似文献
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在Windows XP系统下,使用LabVIEW开发了通信虚拟实验系统.该系统使用虚拟仪器技术,解决了传统通信实验硬件电路构建复杂的缺陷,具有界面友好,维护简单等优点.文中详细介绍了系统的开发背景,软件结构和特点,实验证明该系统具有很好的教学实验效果. 相似文献
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For Pt.I see ibid., vol.19, no.1, p.9-14, January 2004. Dynamics of water penetration in mass impregnated cable insulation has been studied. For experimental purposes, artificial damage has been inflicted to a 40-cm-long cable sample and water ingress has been continuously monitored by frequency response measurements. A similar experiment has been conducted on 2.8-m-long cable sample, where both frequency response and time-domain reflectometry (TDR) measurements have been performed. After termination of both experiments, actual moisture content has been measured radially and axially. Based on dielectric measurements, a model of water ingress has been developed and diffusion coefficients have been estimated for mass impregnated cable paper. 相似文献
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对某600MW汽轮发电机组调试阶段出现的多种振动现象进行了分析.介绍了该机组轴系动平衡方案,分析了动平衡中出现的异常现象,研究了发电机后轴承塑料油档摩擦以及传感器支架刚度不足引起的不稳定振动现象和原因,并对发电机前轴承出现的二倍频振动也进行了研究.采取相应的措施后获得有效处理. 相似文献
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一种新型软开关BUCK变换器 总被引:1,自引:0,他引:1
针对影视照明用大功率电子镇流器的特殊要求,提出了一种新型软开关BUCK变换器。新型电路具有大功率、低损耗等优点。给出了控制策略,阐述了新电路的工作原理。给出了主电路的参数设计方法。对新电路进行了仿真研究。理论和仿真结果表明,新电路中的所有功率开关全是软开关,大大降低了开关损耗。制作了一台输出功率为6kW的实验样机。实验结果与理论和仿真结果吻合。实验结果表明,用新电路代替原来的硬开关电路,整机效率提高了8%,新系统的效率为93%。 相似文献
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The problems of asynchronous self-excitation of a synchronous machine with two windings on the rotor and a series capacitance in the circuit have been considered. A formula for calculating free oscillations has been given. It has been shown that, for a system consisting of a symmetric synchronous machine and a series capacitance, there are two natural frequencies, each corresponding to a certain zone of self-excitation. The equation of the curve that describes the region of self-excitation has been obtained. The effects of different parameters of machine on the lower part of the self-excitation zone have been investigated. It has been shown that this part of the zone is determined by the ratio between the active resistances of the machine circuits, but not their absolute values. A method to determine parameters providing the required compensation of the machine reactance has been given. 相似文献