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51.
为了满足“神光-Ⅲ”原型装置能源系统的需要,桂林金属膜电容器厂研制成功一种高比能脉冲电容器,其尺寸为295 mm×138 mm×730(830) mm,额定电压25 kV,额定电容及偏差为55 μF,0~5 %,损耗角正切值(2.5 kV,50 Hz)小于 0.1%,比能达0.56 J/cm3 。对该型电容器进行性能测试,所得电容偏差都在2%~5%范围,损失角正切值小于0.05%;极间耐压试验全部通过,极-地耐压试验全部通过。寿命试验中,放电电流5 kA,1×104次充放电后,电容量下降1.8%。该型电容器目前已投入运行,工作情况良好。 相似文献
52.
本文采用溶胶凝聚方法制备了超细氢氧化亚镍电极材料并通过在其中掺加适量碳纳米管的方法大大提高了电极的比容量并有效改善了电极材料的阻抗特性。掺有20%碳纳米管的氢氧化亚镍复合电极材料的单电极比容量可达到320 F·g-1。本文分别采用氢氧化亚镍/碳纳米管复合电极作为正极,活性炭作为负极,6 mol·L-1 KOH作为电解液制备了复合型电化学电容器。采用上述方法制备的复合型电容器工作电压达到1.6 V,电容器质量比容量达到60 F·g-1。复合型电容器能量密度达到20.11 Wh·kg-1,最大功率密度达到8.6 kW·kg-1,兼具高能量特性和优良的大电流放电特性。 相似文献
53.
在C/KOH/Ni(OH)2型非对称电化学电容体系中,Ni(OH)2电极需具有快速发生电化学反应的能力与活性炭负极匹配。本文通过增加微集流体的掺杂比例.对活性物质进行球磨处理、固相掺杂碳纳米管等方法对正极进行改性研究。实验发现,增加正极微集流体的掺杂比例.可明显改善非对称电容大电流条件下的容量和循环性能;对正极活性物质进行球磨处理,有利于电极活性物质的转变.加快非对称电容的活化速度;在正极固相掺杂一定比例的碳纳米管可提高非对称电容的充放电效率和容量性质。 相似文献
54.
Enn?LustEmail author Alar?J?nes Mati?Arulepp 《Journal of Solid State Electrochemistry》2004,8(7):488-496
Electrical double layer capacitors based on ideally polarizable nanoporous carbon electrodes in propylene carbonate with the addition of different 1 M Me3EtNBF4, Me2Et2NBF4, MeEt3NBF4, Et4NBF4, Et3PrNBF4 and Et3BuNBF4 electrolytes have been tested by cyclic voltammetry, chronoamperometry and electrochemical impedance methods. The limits of ideal polarizability, low-frequency limiting capacitance and series resistance, time constant, Ragone plots (energy density vs. power density dependencies) and other characteristics have been discussed. The influence of the electrolyte molar mass on the electrochemical characteristics of the nanoporous carbon electrode cells has been established. The applicability limits of the Srinivasan and Weidner model have been tested. 相似文献
55.
56.
Atsunori Matsuda Masahiro Tatsumisago Tsutomu Minami 《Journal of Sol-Gel Science and Technology》2000,19(1-3):581-584
Silica gels doped with several protonic acids such as HClO4, H2SO4 and H3PO4 have been prepared by the sol-gel method and totally solid electric double-layer capacitors have been successfully fabricated using the highly proton-conductive silica gels as an electrolyte and activated carbon powder (ACP) hybridized with the silica gels as a polarizable electrode. It was found that the addition of HClO4, which had the highest value of acid dissociation constant among these three acids, most effectively increased the proton conductivity of the resultant acid-doped silica gels. Tablets of the HClO4-doped silica gels exhibited conductivities as high as 10–5–10–2 S cm–1 at room temperature in dry N2 atmosphere. One of the capacitors fabricated using the protonic acid-doped silica gels had a capacitance of 44 F/(gram of total ACP in the capacitor), which was comparable to those of conventional capacitors using liquid electrolytes. 相似文献
57.
A new multiobjective allocator of capacitor banks and distributed generations using a new investigated differential evolution 下载免费PDF全文
Mohammad Eskandari Nasab Iman Maleksaeedi Mohsen Mohammadi Noradin Ghadimi 《Complexity》2014,19(5):40-54
This article has investigated a new multiobjective allocation of optimal sizing and sitting of distributed generation (DG) units and capacitor banks in simultaneous mode to improve reliability and reduce energy losses. The proposed method consists of four objectives, that is, cost of energy not supplied, system average interruption duration index, costs of energy loss and investment. A novel structure differential evolution has been suggested to solve this nonlinear complex problem and its results are compared with related values of genetic algorithm and simple differential evolutionary algorithm. In addition to the novel objective function, the other contribution of this article is proposing a new model for load and energy cost. Three types of DGs, that is, wind turbine, solar cell, and diesel generator have been used in placement process. To verify the comprehensiveness of the proposed function, three scenarios have been introduced: scenario i: first, placement of DGs, then capacitor banks, scenario ii: first, placement of capacitor banks, and then DGs, and scenario iii: simultaneous placement of DGs and capacitor banks. Simulations have been carried out on one part of practical distribution network in Metropolitan Tabriz in North West of Iran. The results of simulations have been discussed and analyzed using the five novel indices. The obtained simulation results using proposed function shows that the simultaneous placement of DGs and capacitor banks results in more reduction of the energy losses and increase improvements of reliability indices as well as voltage profile. © 2013 Wiley Periodicals, Inc. Complexity 19: 40–54, 2014 相似文献
58.
用电子分析天平测量静电力及真空介电常量 总被引:2,自引:1,他引:1
介绍了用电子分析天平测量平行板电容器两极板间的静电力和真空介电常量的原理和方法. 相似文献
59.
分析了高电场强度下金属化膜电容器绝缘电阻的特点,得出高电场强度下金属化膜电容器绝缘电阻是电容器介质膜泄漏和自愈过程的综合反映。针对高场强下的应用条件提出一种金属化膜电容器绝缘电阻的测试方法,并对高场强下电容器的绝缘电阻进行测试。测试结果表明:在300~400 V/m工作场强范围内金属化膜电容器绝缘电阻随工作场强增大会急剧减小,由于自愈的作用,绝缘电阻下降幅度随场强增加会逐渐变缓;在20~50 ℃工作温度范围内,金属化膜电容器绝缘电阻随温度升高会急剧减小,同样由于自愈的作用,绝缘电阻下降幅度随温度增高会逐渐变缓。分析得出,高温高场强下金属化膜电容器介质膜泄漏将会导致电容器电压出现明显下降,影响电容器和脉冲功率系统的储能效率。 相似文献
60.
以三聚氰胺(M)、间苯二酚(R)和甲醛(F)为原料,经溶胶-凝胶法、超临界干燥和高温碳化制备了系列的氮掺杂碳气凝胶(NCAs)。X射线光电子能谱(XPS)分析表明,氮元素成功地引入到碳气凝胶中,并且可以通过调节三聚氰胺掺杂量来控制氮掺杂量;扫描电子显微镜(SEM)和N2吸附测试显示出不同氮掺杂量的碳气凝胶的微观结构差异较大,随着氮含量的增加,比表面积有先减后增的趋势;在6 mol/L KOH溶液中进行的恒流充放电和循环伏安测试表明,引入氮元素能够极大地改善碳气凝胶的电化学性能,最高比电容量达176 Fg-1,并且凝胶具有良好的电容特性和可逆性。 相似文献