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适用于直流配电网故障选线的电力电子变压器分步闭锁方案 [PDF]
, 2023 级联H桥型电力电子变压器（power electronic transformer with cascaded H-bridge，CHB-PET）是柔性变电站的重要组成设备之一，在直流配电网中具有重要作用。当CHB-PET低压直流侧发生双极短路故障后，故障电流上升速度快且幅值较高，易导致电力电子器件迅速闭锁，使低压直流电网保护难以准确获取故障信息。针对CHB-PET低压侧多分支直流配电网，提出一种基于PET分步闭锁的故障穿越策略。当检测到PET低压侧直流系统故障后 ...
于弘洋 +5 more
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Developmental Medicine &Child Neurology, Volume 61, Issue 3, Page E1-E35, March 2019., 2019 目的 本国际临床指南由欧洲残疾儿童学会（the European Academy of Childhood Disability，EACD）牵头制定，旨在解决发育性协调障碍（developmental coordination disorder，DCD）的定义、诊断、评估、干预以及与社会心理方面的临床应用关键问题。 方法 本指南针对五个领域的关键问题，通过文献综述和专家团队的正式讨论达成共识。为保证指南的循证基础，以“机制”、“评估”和“干预”为检索词, 对2012年更新以来提出的最新建议以及新增的“社会心理问题”和“青少年/成人”为检索词进行检索。根据牛津大学循证医学中心证据等级 (证据水平 [level of evidence, LOE]1–4) 将结果进行分类，最终转化为指南建议。并由国际 ...
Jing Hua +6 more
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Considering connections between Hollywood and biodiversity conservation
Conservation Biology, Volume 32, Issue 3, Page 597-606, June 2018., 2018 Abstract Cinema offers a substantial opportunity to share messages with a wide audience. However, there is little research or evidence about the potential benefits and risks of cinema for conservation. Given their global reach, cinematic representations could be important in raising awareness of conservation issues and species of concern, as well as ...
Matthew J. Silk +3 more
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Dianci bileiqi, 2020 ZnO压敏电阻的老化主要由施加电压及温度因素造成,为研究其在工作电压下的热电特性,利用建立的压敏电阻交、直流老化试验平台,开展了热电应力下压敏电阻温度特性、荷电率特性及直流老化特性的试验研究。结果表明:1)直流电压荷电率（电压与压敏电压的比值）在85%～92%区间,泄漏电流和功耗随荷电率增大有下降趋势,而交流电压下两参数随荷电率的增加而增加; 2)直流老化试验中,在97%荷电率和145℃温度下,10K250压敏电阻的泄漏电流经历了快速下降、缓慢上升、激增3个阶段。泄漏电流的剧增点（增长到初始值的900%）
孙伟 +4 more
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Dianci bileiqi, 2021 ZnO压敏电阻是电子和信息化领域重要的过电压防护器件,对电子与通信系统的运行安全有着至关重要的作用。本研究基于压敏电阻直流老化特性实验平台,开展了热电应力下ZnO压敏电阻温度特性、荷电率特性以及长期直流电压下老化特性的变化规律研究。实验与分析结果证明:1)在电应力与热应力作用下,ZnO压敏电阻的泄漏电流和功率损耗随着荷电率增大而增大;2)同一型号压敏电阻在同温度(115℃),不同荷电率下两组直流老化实验,泄漏电流曲线经历了快速上升、缓慢下降至平稳、激增3个变化阶段,两组老化时间存在较大差异; 3 ...
黄海博, 孙伟, 万翔, 姚学玲
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Rare Metals, Volume 45, Issue 4, April 2026.ABSTRACT Moisture‐enabled electricity generation technology offers a new paradigm for sustainable energy harvesting, but its practical applications are still limited by issues such as low output power and insufficient long‐term stability. In this paper, an asymmetric sandwich‐structured hydrogel moist–electric generator (SSHMEG) with an ion ...
Peng Chen +7 more
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Rare Metals, Volume 45, Issue 3, March 2026.ABSTRACT In conventional piezoceramics, the coordinated change between the dielectric constant (εr) and the piezoelectric charge constant (d33) usually limits the piezoelectric voltage constant g33 (g33 = d33/εr), a critical figure of merit for piezoelectric sensors.
Xiaoying Feng +7 more
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Rare Metals, Volume 45, Issue 2, February 2026.ABSTRACT Early detection of thermal runaway (TR) is essential for lithium‐ion battery (LIB) safety, as unchecked TR risks catastrophic failures in energy storage systems. Gas‐based sensing offers a faster and more direct approach by detecting decomposition products at the molecular level.
Tianshui Liang +9 more
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考虑谐波谐振和电压稳定的海上风电场无功优化配置方法 [PDF]
, 2023 海上风电经长距离高压交流海底电缆接入电网，海底电缆容升效应显著，容易引起工频过电压，同时电力电子器件和线路电容引起的谐波谐振问题也严重影响着电网电能质量，因此进行海上风电场无功配置时应充分考虑过电压和谐波谐振问题。针对上述问题，建立了海上风电场谐波模型，对海上风电场的谐波模态阻抗进行扫描，继而分析海上风电场的谐振特性；然后研究了海上风电场无功特性，计算各种发电出力水平和并网点电压下的风电场无功缺额；接着以降低综合成本为目标，以静态电压稳定裕度、最小补偿容量、谐波谐振及过电压为约束 ...
马明, 梅桂华, 杜婉琳*, 王玲
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Dianci bileiqi, 2016 ZnO压敏电阻连接在电路中工作时,两端一直承受交流负载电压的老化,为探究在多脉冲情况下,交流负载电压对ZnO压敏电阻的性能影响,采用幅值为20 k A、时间间隔为50 ms的8/20μs同时序冲击高压多脉冲对并联氧化锌压敏电阻元件进行冲击的同时施加幅值为385 V的工频交流电压模拟压敏电阻实际安装在电路上的真实工作环境。经过施加交流负载和不加交流负载的两组试验对比分析,得出结论:交流负载施加与否对初始压敏电压相同的两片压敏电阻并联的耐受多脉冲冲击次数没有影响,但会导致压敏电阻损坏效果不同;施加交流负载时,
肖扬 +4 more
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