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聚合物绝缘材料的漏电起痕性 总被引:4,自引:0,他引:4
叙述了聚合物绝缘材料漏电起痕的形成机理,聚合物绝缘材料的结构对漏电起痕的影响进行了分析,含有共轭双键.苯核,杂环的聚合物绝缘材料耐漏电起痕差。对国内常用聚合物绝缘材料耐漏电起痕性能作了评价,为了提高耐漏电起痕性,除了使用不含或少含共轭双键结构的聚合物外,可加入适量的氢氧化铝。 相似文献
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本文叙述了我国电气用玻璃纤维增强不饱和聚酯模塑料(SMC/BMC)标准现状及存在的问题,并着重介绍了GB/T 23641—2009"电气用纤维增强不饱和聚酯模塑料(SMC/BMC)"国家标准与JB/T 7770—1995"电气用纤维增强不饱和聚酯模塑料(SMC/BMC)"机械行业标准的主要差异,对今后标准化工作提出了一些建议。 相似文献
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聚烯烃绝缘子具有优异的电性能、憎水、机械强度和刚性等优点,但其憎水迁移性能和耐漏电起痕是研究难点。通过长链脂肪胺与全氟烷基丙烯酸酯加成反应,合成了一种新型的含氟固态憎水剂,研究其对聚烯烃材料的憎水迁移性、耐漏电起痕、机械强度等性能影响。结果表明:添加质量分数1%憎水剂后,样品表面可富集含氟化合物,在不影响绝缘、机械强度和耐漏电起痕性能(1A4.5级)的前提下,提高了改性样品的憎水迁移性能。在标准污层下憎水迁移96 h,表面水接触角由71.7°增长到90.7°,水中浸泡96 h后的接触角保持在100°以上。进一步研究发现含氟憎水剂还具有延长结冰时间和降低覆冰粘附力的效果。该研究为新型聚烯烃绝缘子的输电线路可靠应用提供了理论和技术支持。 相似文献
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高压绝缘防污闪涂层的研究进展 总被引:3,自引:2,他引:3
室温硫化(RTV)硅橡胶以其独特的憎水性和憎水迁移性而被用作新型高压绝缘防污闪材料,但仍存在附着力差,强度弱,阻燃性差等缺陷。为提高RTV硅胶的防污闪作用,进一步开展相关的研究工作,综述了污闪产生的机制,RTV硅胶的组成及特点、研究与应用。在概述了国内外RTV硅胶研究近况和RTV硅胶的小分子憎水迁移机理后阐明了纳米技术有效提高RTV硅胶的机械性能和耐老化性能,阻燃剂(如氢氧化铝)改善RTV硅胶的耐漏电起痕性、阻燃性能等的效果。最后指出,进一步提高RTV硅胶的机械性能、电气性能、抗老化性能是今后研究工作的热点。 相似文献
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Atsushi Tsujita Masashi Ohchi Takayuki Wakimoto 《Electrical Engineering in Japan》2019,208(1-2):17-26
We have been studying on estimating distribution of permittivity between measurement electrodes using capacitance and electric potential. Two arc electrodes were separated by long distance and there electrodes were surrounded by additional electrodes respectively. In past research work, we carried out numerical electric analysis for calculating the capacitance and electric potential using Finite Element Method (FEM) and compared with experimental and numerical results. The capacitance values were almost agreed with experimental and numerical results. However, the electric potential values were different between experimental and numerical results in conventional studies. In this paper, we proposed an equivalent circuit including the stray capacity and measurement method for capacitance, the electric potential in space between long distance electrodes was estimated. 相似文献
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为了解特高压交流输电线路邻近建筑物时畸变电场,采用有限元法计算了1 000kV交流同塔双回输电线路邻近不同结构和材料建筑物时的工频电场。首先建立了含弧垂导线、钢架和空气场域的计算模型和有限元模型;然后计算分析了钢架附近地面、阳台和屋顶的工频电场,通过与实验模型比较验证了计算方法的有效性;最后分析了钢筋和砖土材料房屋楼顶的畸变电场,比较了2种房屋是否开窗时阳台和室内的场强。结果表明,有限元法可有效计算建筑物周围的工频电场;靠近导线侧房屋棱角及棱边附近工频电场畸变较大,钢筋和砖土房屋楼顶棱边中心处畸变电场分别为10.40kV/m和6.02kV/m,较不存在房屋时分别畸变了123.18%和29.18%;砖土材料对室内电场屏蔽效果较差,其一层室内最大场强可达4.82kV/m;开窗会使钢筋房屋阳台处电场从32.2mV/m增大到1.95kV/m,但砖土房屋阳台电场变化较小。 相似文献
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To examine the sensitivity to geomagnetically induced currents (GIC) of the Hydro-Quebec 735 kV power system, model calculations were made of the GIC produced by uniform electric fields directed northwards (azimuth of 0°) and with azimuths increasing in 15° increments. The results show that the maximum GIC was produced in the system for an electric field bearing of 15°. In addition the model results allow the variation of GIC amplitude with electric field direction to be examined for individual substations. Maximum GIC occurred at substations at the ends of a long transmission line when the electric field was aligned with the transmission line 相似文献
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Changho Lee Vassili Spirin Yongbae Jeon Daewon Kim Kwangsoo No 《Integrated ferroelectrics》2013,141(1-4):439-451
Abstract PZT thin films were fabricated on ITO/glass substrates using sol-gel method. The main processing variable was the drying temperature: 300, 350, 450 and 500°C. The microstructure and electric properties (polarization and dielectric constant) were investigated. The electric properties were dependent on the perovskite phase content and the grain size affected by the nucleation of perovskite phase. The two-beams polarization interferometer was used for the measurement of electro-optic coefficients of PZT thin films, and these values were analyzed by comparing the electric properties. 相似文献
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介绍了铅蓄电池、金属氢化物-镍蓄电池、锂离子蓄电池及聚合物锂离子蓄电池、锌-镍蓄电池、锌空电池和氢燃料电池作为电动自行车、电动汽车以及混合电动车动力电源的优缺点;分析了上述蓄电池在电动车上的应用现状和应用前景。 相似文献
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干式直流套管作为换流变、阀厅的重要组成部分,极板边缘的电场最大,局部放电最易从该处起始,进而引发绝缘失效,如何有效优化极板边缘处的电场已经成为提高干式直流套管运行可靠性的关键。为进一步确定干式直流套管极板边缘电场分布规律及优化方法,建立了双层电容屏套管芯体模型,分析了不同电容屏参数下传统经验公式的准确性,并对比了铝箔边缘半折边、敷设半导电绝缘纸、敷设非线性电导材料等方法对极板边缘电场的优化效果。结果表明,传统经验公式对极板边缘的最大电场估计偏小,且偏差基本不随d/Δt变化,约为7.5%。此外,极板边缘半折边方法可以使极板边缘曲率半径增大1倍,最大电场降低27.8%。极板边缘敷设环氧浸纸材料电导率10~100倍的半导电纸可以使极板边缘最大电场降低超过31.4%,且再增大半导电纸电导率,极板边缘最大电场几乎不再下降。极板边缘附着非线性绝缘材料方法是一种有前景的方法,可以使极板边缘最大电场下降达73.2%。 相似文献