共查询到20条相似文献,搜索用时 156 毫秒
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充油电缆最重要的性能指标是电缆的介质损耗,而电缆的介质损耗与电缆油密切相关。查阅相关的产品标准,除IEC等标准对充油电缆铝导体的直流电阻有规定外,我国的国家标准及其它一些国家标准仅规定了铜芯充油电缆。铝芯充油电缆的生产难点在于,铝单线拉制过程中沉积在单线表面的铝大拉油及导体生产过程中产生的铝灰,将通过充油电缆油道对电缆油产生污染,从而影响电缆的介质损耗。我公司通过不断摸索,在包括铝单线拉制、退火、铝单线清洗、中空铝导体绞制等方面采取了大量的措施后,研制出的铝芯充油电缆,电缆油的介质损耗角正切tgδ为0.000 4,电缆的tgδ为0.002 2,与我公司生产的铜芯充油电缆相当。 相似文献
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本文介绍了浙江晨光电缆集团公司成功建立的500 kV交联聚乙烯(XLPE)电缆局放屏蔽试验大厅,并阐明了设计理念。屏蔽室尺寸:长28.0 m×宽21.0 m×高15.0 m;大门:宽5.5 m×高6.0 m,供有电缆盘进出的25 t轨道车。试验电源:10 kV,500 kVA经专用电缆供电。接地电阻0.14Ω;地下绝缘槽电阻>103MΩ;屏蔽系数(衰减值):80~100 dB(局放频带)。高压测试设备由德国High Volt公司提供,整体试验表明:系统空载输出电压700 kV时,局放水平≤0.8 pC。 相似文献
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介绍了一种SMA型高性能电缆连接器的研制过程。该产品采用内外导体焊接结构端接柔软电缆,并采用绝缘介质错位补偿的办法减小信号反射。 相似文献
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Hiroshi Suzuki Toshihiro Takahashi Tatsuki Pokamoto Noboru Ishii Shin‐Ichi Mukoyama Akio Kimura 《Electrical Engineering in Japan》2008,164(2):25-36
A High‐Temperature Superconducting (HTS) cable has a bulk power transmission capacity as a candidate for the replacement of aged cables and/or for the increase of the power transmission capacity, and its diameter is preferred to be smaller than the inner diameter of the duct for the existing cables. To reduce the diameter of HTS cable, the cold dielectric (CD)‐type electrical insulation in which a cable core is immersed into liquid nitrogen (LN2) should be adopted, and the thickness of its electrical insulation layer has to be optimized. Since a partial discharge (PD) in the electrical insulation layer of the CD‐type HTS cable is considered as a major cause for the aging of the insulation layer, PD‐free design must be adopted for the CD‐type HTS cable. This paper describes a design method for the electrical insulation layer of the CD‐type HTS cable adopting the PD‐free design under AC stress, based on the experimental results such as a PD inception stress (PDIE), an impulse breakdown stress, and PD extinction characteristics under AC stress superimposed with an impulse stress. Moreover, the proposed design method was applied to a 500‐m HTS cable and was verified by a field test. © 2008 Wiley Periodicals, Inc. Electr Eng Jpn, 164(2): 25–36, 2008; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/eej.20512 相似文献
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Forsyth E.B. Muller A.C. Muller T.R. Ernst A. Purnhagen D.W. 《Power Delivery, IEEE Transactions on》1990,5(3):1248-1255
The testing of oriented polyethylene tape with an embossed surface design for use as oil-impregnated insulation for flexible power cables is described. The development was carried out with small samples in the form of sheets, small cylindrical samples about 1 m long, and long cables either 15 m or 100 m long. Tests with these experimental configurations included investigating: (1) breakdown stress and statistics of breakdown; (2) dielectric loss measurements; (3) design of screens; (4) design of splices; (5) mechanical problems of taping and installing cables; and (6) oil impregnation and type of oil. The results point the way to the next development steps. These are: (1) development of thinner embossed tapes to exploit the potential of the high dielectric strength inherent in synthetic taped insulation; (2) development of accessories such as splices and terminations; and (3) complete system design to avoid a dramatic increase in dielectric loss caused by oil contamination. If the integrity of the insulation homogeneity can be maintained, it appears the high voltage breakdown stresses will be adequate to permit economical operation 相似文献
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冷绝缘高温超导电缆的导电层一般设计为多层结构以满足大电流载流特性,但伴随层数的增加,超导体上的集肤效应会引起电缆输电导体各层电流分布不均匀的问题,从而造成电缆损耗增加和传输性能下降。采用基于动态惯性权重因子的粒子群优化算法,提出了电缆导体层电流层间均流优化的设计方法。应用第2代高温超导材料钇钡铜氧涂层导体,通过建立超导电缆的等效电路模型,考虑电场、磁场等约束因素,对一根1km长,110kV/3kA等级的冷绝缘高温超导电缆进行优化设计,获得了电缆本体结构参数及输电导体层和屏蔽层的电流分布。比较优化前后层电流的结果可知,优化后超导电缆各导体层电流与平均电流相比最大不平衡率小于3.5%,各屏蔽层电流达到均布,较好地实现了电缆各导体层电流均匀分布的优化目标。最后,超导模型样缆载流特性实验也验证了优化设计方法的有效性。 相似文献
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高温超导电缆在城市地下输电系统应用的可行性研究 总被引:1,自引:1,他引:1
大城市有可能最先采用商业化运行高温超导电缆 ,用于城市地下交流输电系统。其主要应用目标是用于地下电缆工程改造 ,利用现有排管以高温超导电缆取代现有的常导电缆 ,增加地下电缆传输容量以及采用高温超导电缆将巨大电能 (1GVA以上 )输入到城市负荷中心。采用常导电力电缆传输 1GVA以上的电能进入中心城区 ,输电电压一般要求为 5 0 0 k V。在城市中心区不可能建设 5 0 0 k V变电站。 5 0 0 k V电缆线路所需的 5 0 0 k V大长度电缆和相应附件 ,目前尚未研制开发。采用高温超导电缆将有可能降低输电电压等级 ,可以采用 2 2 0 k V高温超导电缆将 1GVA以上的电能输入到城市负荷中心 ,满足特大型城市负荷中心供电需求。采用 110 k V高温超导电缆 ,亦有可能传输 1GVA左右电能。本文通过对交流高温超导电缆系列设计计算对额定电压 35 k V、110 k V、2 2 0 k V的高温超导电缆 ,按不同传输电流 (或传输容量 ) ,以高温超导电缆的传输效率 (损耗与传输容量比 )、高温超导电缆外径限值和超导导体绕制结构限制条件 ,确定高温超导电缆适用性界定条件 ,提出城市地下输电、配电系统用高温超导电缆可行方案。 相似文献
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与常规电缆相比,高温超导电缆具有体积小、重量轻、容量大、电流密度高、损耗低、环境友好等优势,为未来电网提供了一种新的电力传输方式。随着高温超导线材取得的重要研究进展,国际上相继开展了高温超导电缆的研发,已有多条超导电缆工程成功地进行了挂网示范运行。本文介绍高温超导电缆的研发进展情况,并简单对高温超导电缆的发展趋势和关键技术做出展望。 相似文献
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Sauers I. James D.R. Ellis A.R. Pace M.O. 《Dielectrics and Electrical Insulation, IEEE Transactions on》2002,9(6):922-931
The discovery of high temperature superconductors (HTS) has triggered renewed interest in the study of dielectric materials at cryogenic temperatures. While considerable work was done in the 1970s and 1980s on dielectrics immersed in liquid helium for low temperature superconducting applications, there remains a need for dielectric research at liquid nitrogen temperature for HTS applications, requiring experimental data oriented toward practical situations. We report on AC breakdown (puncture and/or flashover), and impulse breakdown of solid materials in either vacuum or in liquid nitrogen. Solid materials which we examined, include fiberglass reinforced plastics, epoxies with and without filler, and polymeric tape. Combinations of some of these materials have also been studied at low temperatures. Additionally we have measured permittivity and dissipation factor for materials for which these parameters are not available at 77 K. Finally, we also discuss specific applications for HTS cables including breakdown and aging studies on model cables, with lapped tape electrical insulation, immersed in liquid nitrogen. 相似文献
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高温超导电缆具有不同于常规电缆的优越特性,已在国内外研制成功并在工程中实验和应用。介绍了高温超导体特性和高温超导电缆,简要分析了国内外高温超导电缆的研究进展、应用现状和项目实例,对高温超导电缆在城市电网的应用前景作了初步探讨。 相似文献