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排序方式: 共有598条查询结果,搜索用时 15 毫秒
61.
62.
王香芳 《电力电容器与无功补偿》2003,(Z1)
本文主要介绍了765kV电容式电压互感器的研究和设计。对0.1级高精度、电气绝缘性能、机械强度和瞬变响应特性等关键技术问题进行了分析论证、计算和试验验证。 相似文献
63.
64.
In this study, we present an effective strategy to enhance the energy storage properties of Ba0.4Sr0.6TiO3 (BST) lead-free ceramics by the addition of Bi2O3-B2O3-SiO2 (BBS) glass, which were prepared by the conventional solid state sintering method. The phase structure, microstructure and energy storage properties were investigated in detail. It can be found that the Ba0.4Sr0.6TiO3-x wt%(Bi2O3-B2O3-SiO2) (BST- x wt%BBS, 0 ≤ x ≤ 12) ceramics possess large maximum polarization (Pmax), low remanent polarization (Pr) and slim polarization electric field (P-E) hysteresis loops. The breakdown strength (BDS), recoverable energy storage density (Wrec) and energy storage efficiency (η) are enhanced obviously with the addition of BBS glass. The BST-9 wt%BBS ceramic is found to exhibit excellent energy storage properties with a Wrec of 1.98 J/cm3 and a η of 90.57% at 279 kV/cm. These results indicate that the BST-x wt%BBS ceramics might be good candidates for high energy storage applications. 相似文献
65.
为了对粉体颗粒摩擦荷电过程进行数值模拟,以菱镁矿粉体颗粒为研究对象,利用离散元模型和电荷转移模型对粉体颗粒运动过程和摩擦荷电过程分别进行理论建模。在EDEM仿真软件中建立了适用于粉体颗粒摩擦荷电仿真的计算模块,并应用该模块进行菱镁矿粉体摩擦荷电仿真分析,考察给料量和滑槽倾斜角度对摩擦荷质比的影响,同时利用振动槽摩擦荷电装置进行菱镁矿粉体颗粒摩擦荷电对比实验研究。结果表明,菱镁矿粉体摩擦荷质比随给料量的增加而减小,随滑槽倾斜角度的增大而减小。试验结果得到了与仿真结果相似的变化趋势,验证了所建粉体颗粒摩擦荷电数值模型的准确性。本文研究结果对更精确粉体颗粒摩擦荷电模型的建立和粉体颗粒摩擦带电的进一步应用具有重要意义。 相似文献
66.
《Ceramics International》2021,47(22):31590-31596
In this study, the high ferroelectric hysteresis loss of (Pb0·93La0.07)(Zr0·82Ti0.18)O3 (PLZT 7/82/18) antiferroelectric (AFE) ceramics was reduced by employing a combinatorial approach of Mn acceptor doping followed by thick film fabrication via an aerosol deposition (AD) process. The grains of the as-deposited PLZT 7/82/18 AFE AD thick films were grown by thermal annealing at 550 °C to enhance their electrical properties. Investigation of the electrical properties revealed that Mn-doping results in improved dielectric and ferroelectric properties, increased dielectric breakdown strength (DBS), and energy-storage properties. The Mn-doped PLZT AFE AD films possess a frequency-independent high dielectric constant (εr ≈ 660) with low dielectric loss (tan δ ≈ 0.0146), making them suitable candidates for storage capacitor applications. The bipolar and unipolar polarization vs. electric field (P-E) hysteresis loops of PLZT 7/82/18 AFE AD thick films were found to be slimmer than those of their bulk form (double hysteresis) with significantly reduced ferroelectric hysteresis loss, which is attributed to the AD-induced mixed grain structure. The Mn-doped PLZT 7/82/18 AFE AD thick films exhibited a low remnant polarization (Pr ≈ 9.22 μC/cm2) at a high applied electric field (~2750 kV/cm). The energy-storage density and energy efficiency of the Mn-doped PLZT AFE AD thick films were calculated from unipolar P-E hysteresis loops and found to be ~38.33 J/cm3 and ~74%, respectively. 相似文献
67.
Tareq Salameh Mohammad Ali Abdelkareem A.G. Olabi Enas Taha Sayed Monadhil Al-Chaderchi Hegazy Rezk 《International Journal of Hydrogen Energy》2021,46(8):6014-6027
Renewable energy resources play a very important rule these days to assist the conventional energy systems for doing its function in the UAE due to high greenhouse gas (GHG) emissions and energy demand. In this paper, the analysis and performance of integrated standalone hybrid solar PV, fuel cell and diesel generator power system with battery energy storage system (BESS) or supercapacitor energy storage system (SCESS) in Khorfakkan city, Sharjah were presented. HOMER Pro software was used to model and simulate the hybrid energy system (HES) based on the daily energy consumption for Khorfakkan city. The simulation results show that using SCESS as an energy storage system will help the performance of HES based on the Levelized cost of energy (LCOE) and greenhouse gas (GHG) emissions. The HES with SCESS has renewable fraction (68.1%) and 0.346 $/kWh LCOE. The HES meets the annual AC primary load of the city (13.6 GWh) with negligible electricity excess and with an unmet electrical load of 1.38%. The reduction in GHG emissions for HES with SCESS was 83.2%, equivalent to saving 814,428 gallons of diesel. 相似文献
68.
大容量电容器组桥差不平衡电流保护近似计算 总被引:2,自引:3,他引:2
本文对工程上大容量电容器组的不平衡保护计算进行了简化,使得计算公式简单实用。 相似文献
69.
电力电容器的故障分为内部故障和外部故障,本文以星形接线的三相电容器组为例。对电容器内部故障产生时电容器的相关电量加以分析。 相似文献
70.
高军 《电力电容器与无功补偿》2008,29(6):10-11,42
电容器的内部故障保护配置随着电容器结构、接线方式的不同,存在着较大的差别,使整定计算人员难于掌握。现就电容器内部故障保护配置及整定时的关键点、应注意的问题进行详细的论述。 相似文献