Results 11 to 20 of about 190,254 (168)
Gaoya dianqi, 2010 电力系统中出现的波形、幅值及持续时间各异的多种过电压对电气设备绝缘构成了严重威胁。鉴于电力系统过电压波形包含了丰富的电力系统工作状况和状态信息,笔者重点对电力系统过电压波形进行了分析,将从变电站过电压在线监测系统获取的雷电感应过电压、投电容器组过电压、合空载线路过电压、投切空载变压器过电压、弧光接地过电压、不对称接地短路共7种典型过电压波形作为对象,分析其主要特征,并通过小波变换,使含有高频分量的过电压特征在时频域得到更好的体现,为过电压特征提取及类型识别奠定基础。
郭良峰 +5 more
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Rare Metals, Volume 45, Issue 5, May 2026.ABSTRACT Layered double hydroxides (LDHs) are attractive non‐noble catalysts for overall water splitting (OWS), yet their hydrogen evolution reaction (HER) activity is often limited by suboptimal *H adsorption and a paucity of accessible sites. Herein, we introduce an oxygen‐vacancy (Ov) engineering strategy to construct ultrathin Ni‐Fe LDH nanosheets ...
Qi Liu +8 more
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Rare Metals, Volume 45, Issue 5, May 2026.ABSTRACT The development of high‐voltage aqueous zinc‐ion batteries (AZIBs) is primarily hindered by the lack of suitable cathode materials and electrolytes that can work in broad voltage windows. Herein, we propose a synergistic strategy that concurrently addresses these challenges through the integration of an amorphous vanadium oxyphosphate/graphene
Xianyu Liu +7 more
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Gaoya dianqi, 2019 变压器空载合闸过程中由于电磁振荡产生过电压,若系统中存在高压电缆,电缆内部过电压耦合到电缆护层造成护层上电压较高,护层过电压与电缆布置方式和护层接地方式有关。文中针对白莲河抽水蓄能电站主变空载合闸时,电缆端部有异常放电声,并可见放电火花的现象,对主变空载合闸时系统产生的过电压进行测量,并对放电现象进行观测;同时采用ATP/EMTP软件计算空载合闸过电压耦合到电缆护层上的过电压大小。测量结果表明:空载合闸时主变侧过电压值并不大,进而计算得到放电处护层过电压最大值为21.49 kV,频率在600 kHz以内,
张才军 +6 more
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Rare Metals, Volume 45, Issue 5, May 2026.ABSTRACT Phase‐change memory (PCM), characterized by its reversible transition between crystalline and amorphous phases, has emerged as a promising candidate for neuromorphic memory computing applications. However, conventional PCM devices lack an insufficient RESET/SET voltage ratio, which often leads to incorrect recording of the RESET state and ...
Zihan Liu +8 more
wiley +1 more source
Dianci bileiqi, 2019 近年来,电容电压互感器（CVT）在我国电力系统中得到越来越广泛的应用,需要详细研究雷电过电压引发CVT铁磁谐振特性及相应防护措施。通过在EMTP软件中建立35 kV变电站系统模型,分析线路遭受雷电直击或雷电感应时CVT铁磁谐振过电压特性,讨论过电压保护器件和阻尼装置等不同消谐措施的效果,最后分析线路安装避雷器或避雷线对铁磁谐振的抑制效果。研究结果表明:雷电过电压引发的CVT一次侧过电压波形振荡明显,雷电感应情况下过电压频谱范围更宽; CVT一次侧过电压幅值随着雷电流幅值的增加而增大 ...
郭亮 +7 more
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Rare Metals, Volume 45, Issue 4, April 2026.ABSTRACT Photocatalytic hydrogen evolution technology is a crucial approach to achieve efficient solar energy conversion and green hydrogen production. However, traditional semiconductor photocatalysts often face issues such as weak visible‐light response, high photogenerated charge carrier recombination, and poor structural stability, severely ...
Longtao Guo +8 more
wiley +1 more source
Dianci bileiqi, 2018 智能电表的广泛应用伴随着严重的雷电灾害威胁,需要对智能电表雷电感应过电压防护进行详细分析。利用ATP软件搭建配电系统模型,编程计算线路雷电感应过电压,分析雷击点距线路距离和回击速度对智能电表终端过电压的影响,讨论安装线路避雷器、变压器低压侧避雷器、末端SPD的防护效果。分析结果表明:10 kV线路附近发生雷击时,感应过电压传递至智能电表终端时幅值仍然较高,50 kA雷电流幅值下终端过电压超过IV类设备冲击耐受电压;智能电表终端过电压随着雷击点距线路垂直距离的增加、回击速度的减小而降低 ...
王兆军 +6 more
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Rare Metals, Volume 45, Issue 4, April 2026.ABSTRACT Piezocatalytic technology utilizes mechanical strain or stress‐induced piezoelectric phenomena to produce robust internal electric fields, markedly improving the separation efficiency of e−‐h+ pairs. This method has emerged as a focal point in catalysis by removing reliance on conventional light or electrical energy via its mechanical‐to ...
Yue Zhou +5 more
wiley +1 more source
基于真空断路器预击穿特性的海上风电场集电网合闸暂态过电压仿真研究
Gaoya dianqi, 2019 海上风电场中压电缆集电系统真空断路器在闭合空载变压器操作中,真空断路器预击穿会在机端变压器的高压侧产生暂态过电压,该过电压与电缆作用产生高频振荡过电压将对变压器绝缘产生损坏。文中研究真空断路器预击穿产生高频暂态过电压的机理,在PSCAD/EMTDC暂态分析软件上搭建真空断路器预击穿现象的自定义模型,并将此模型应用于简化的海上风电场中压电缆集电系统模型,研究合闸初相角、电缆长度和机端变压器位置对暂态过电压的影响。仿真结果表明机端变压器位于机舱且合闸初相角为15°过电压陡度最大 ...
吴俊臣 +3 more
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