Results 1 to 10 of about 3,930 (119)
Gaoya dianqi, 2021 单芯电缆的结构参数和运行环境影响都会导致电缆的无功损耗变化。为了探究单芯电缆结构和运行环境对电缆无功损耗的影响,文中从电缆内部结构出发,建立了电缆等效电路模型。通过分析电缆内部无功损耗形式,研究了单芯电缆在特殊工况下的无功损耗变化情况。结果表明:单端接地电缆内部损耗以容性无功损耗为主;电缆电压等级越高时,输送一定功率的极限传输距离反而越短,并给出了66、110、220、330、500 kV电缆的极限传输距离;电缆内部进水后容性无功损耗会增大10%～30%,电压等级越高或者电缆截面积越大 ...
李瑞芳 +5 more
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Gaoya dianqi, 2021 为研究谐波电流损耗特性对特高压干式平波电抗器热效应的影响,文中分析了干式平波电抗器的损耗机理,提出了其包封绕组直流损耗、交流损耗及涡流损耗和结构件涡流损耗的计算方法。通过将电磁损耗密度添加至温度场作为热源,建立了电磁—热多物理场映射关系,较准确地模拟了对流换热过程并实现了温升计算,最后开展了干式平波电抗器温升试验。研究结果表明:采用考虑谐波损耗特性的计算方法,计算值与试验值最大误差为9.1%,平均误差为4.34%,温升分布规律吻合较好,满足工程精度要求,为工程设计人员提供了相应的理论依据。
李星汉, 李永建, 张长庚, 高冲
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Dianci bileiqi, 2021 在大电流运行条件下,欧姆损耗是特高压换流变压器穿墙套管封堵发热的重要因素。基于有限元法建立套管与封堵挡板的计算模型,计算得出封堵挡板的欧姆损耗。通过改变内外挡板是否通过接地线相连、挡板厚度、磁导率、电阻率,挡板与套管接触类型,分析上述因素对封堵挡板欧姆损耗的影响。通过计算得出内外挡板是否通过接地线连接对挡板欧姆损耗影响很小,因此,可在计算模型中忽略接地线。随着挡板厚度的增加,挡板总的欧姆损耗大致呈现增长趋势,但平均欧姆损耗显著下降。在挡板厚度较小,相对磁导率小范围变化时,挡板的磁导率对欧姆损耗的影响较小。
陶瑞祥 +3 more
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Rare Metals, Volume 45, Issue 10, October 2026.ABSTRACT Reflection loss (RL) ≤ −15 dB (corresponding to 96.875% electromagnetic energy absorption), a core metric for moderate‐ to high‐temperature (< 600°C) electromagnetic protection materials, is critical for ensuring the reliability of aerospace high‐temperature structural components.
Chunyan Ding +10 more
wiley +1 more source
Gaoya dianqi, 2021 准确计算换流阀及其中各类元部件运行损耗,是进行换流阀及其阀冷系统设计的基础。文中在分析换流阀中主要损耗源基础上,建立了晶闸管、电抗器的高精度等效仿真模型,提出了换流阀损耗的仿真计算方法。以此为基础,计算了额定工况下锡盟站换流阀中各主要元部件损耗功率,并将总损耗计算结果与理论计算值及现场测试数据进行了对比分析。结果表明:仿真方法具有较高精度,可被用于换流阀总损耗计算,以及阀内各发热器件的功率计算。
娄彦涛, 袁妮, 刘琦
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Rare Metals, Volume 45, Issue 10, October 2026.ABSTRACT Magnetic particles coated with carbon shells have been considered as promising electromagnetic wave absorption materials with antibacterial features. However, how to precisely control the monodispersed magnetic nanoparticles on a carbon matrix to manipulate impedance matching and antibacterial performances is still a key challenge.
Xiaofei Li +10 more
wiley +1 more source
Dianci bileiqi, 2020 MOV静态下的功率损耗是影响其热稳定的重要因素,在考虑了老化因素对MOV功率损耗的影响后提出了老化程度变量并将其量化的新方法,并利用自适应模糊推理系统（ANFIS）将电压（V）、温度（T）、老化程度（AD）作为网络的输入,实验测量数据作为训练样本对MOV的功率损耗进行评估。研究表明:ANFIS可有效评估MOV的功率损耗,其最大相对误差为8.
牛春霞, 于忠江, 杨仲江
doaj
Rare Metals, Volume 45, Issue 9, September 2026.ABSTRACT Traditional electromagnetic shielding materials mainly focus on attenuating electromagnetic interference (EMI), but they still fail to meet the growing demands of modern flexible electronic devices and Internet‐related information technologies.
Zhi Lei +6 more
wiley +1 more source
Rare Metals, Volume 45, Issue 8, August 2026.ABSTRACT In Co‐based alloys, the γ phase is normally stable at high temperatures and the ε phase at low temperatures, and there is a martensitic transition on cooling to ∼417°C. In the γ/β dual‐phase CoCrAlY bond coat of turbine blade thermal barrier coating systems, we observed the opposite: γ remained stable at room temperature, yet it underwent a γ →
Junkai Liu +8 more
wiley +1 more source
Rare Metals, Volume 45, Issue 8, August 2026.ABSTRACT Ultrathin, lightweight, and mechanically compliant electromagnetic interference (EMI) shields are increasingly required for high‐frequency electronic devices. However, conventional metallic shields predominantly rely on conductivity‐driven reflection mechanisms, which become ineffective at reduced thickness and may cause severe secondary ...
Zida Zhang +7 more
wiley +1 more source