Results 1 to 10 of about 2,495 (108)

Analysis on Influence Factors of Temporary Overvoltage of Load Rejection Fault of Offshore Wind Power Transmission System of Permanent Magnet Synchronous Generator [PDF]

open access: yes, 2022
In order to evaluate the temporary overvoltage level of the wind power transmission system based on permanent magnet synchronous generator (PMSG) in case of load rejection, it is necessary to clarify the temporary overvoltage characteristics and its ...
CHEN Qiyu   +6 more
core   +1 more source

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]

open access: yes, 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 ...
杜婉琳*, 梅桂华, 王玲, 马明
core   +1 more source

Associations among traumatic experiences, threat exposure, and mental health in Pakistani journalists

open access: yesJournal of Traumatic Stress, Volume 35, Issue 2, Page 581-592, April 2022., 2022
Abstract Pakistan is considered to be relatively unsafe for journalists; however, little is known about how working in situations that involve a high risk of trauma exposure and personal threat impacts journalists’ mental health. The present study aimed to examine the associations among reporting on topics that carry a high risk of trauma exposure ...
Suzanna M. Koster   +3 more
wiley   +1 more source

International clinical practice recommendations on the definition, diagnosis, assessment, intervention, and psychosocial aspects of developmental coordination disorder – Chinese (Mandarin) translation

open access: yesDevelopmental 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
wiley   +1 more source

海上风电场经海底电缆送出系统的并联电抗器配置方案

open access: yesGaoya dianqi, 2022
海底电缆较大的充电功率导致海上风电输电系统的工频过电压较严重,可采用高压并联电抗器进行限制。文中以中国某220 kV海上风电场为例,对其工频过电压进行了理论计算,并利用电磁暂态计算程序(alternative transient program-electro magnetic transient program,ATP-EMTP)建立了海上风电场经交流海缆送出系统模型,计算了输电系统工频过电压分布,进而对高压并联电抗器配置方案进行了分析。研究表明系统侧甩负荷过电压远大于风场侧甩负荷过电压 ...
张文君   +7 more
doaj  

Summary and Prospect of Comprehensive Evaluation Methods of Power Quality [PDF]

open access: yes
ObjectivesWith the continuous development of China's new power system, there is a growing integration of new energy sources such as photovoltaic and wind power into the grid.
DONG Guangde, XIAO Bai, ZHAO Xuechun
core   +1 more source

基于避雷器TOV特性扩展华北风电集送系统工频过电压限值的研究 附视频

open access: yesDianci bileiqi, 2022
华北地区风电集中式送出系统的过电压现行规则中,短时限内工频过电压限值要求有待进一步明确和细化,为此提出了基于避雷器暂时过电压(TOV)耐受特性的系统工频过电压运行规则扩展。在梳理总结现行标准对系统过电压运行要求的基础上,划分了工频过电压安全运行、禁止运行和待定3种情况。通过统计分析华北地区风电集中式送出系统各电压等级避雷器TOV耐受特性数据,扩展了电力系统短时限内工频过电压的安全运行限值。提出将0.1 s短时限内工频过电压上限由现行规定限值扩展至避雷器0.1 s工频耐受电压值 ...
doaj  

Orbitally Driven Anomalous Thermal Transport Under High Pressure in Gallium Nitride

open access: yesRare Metals, Volume 45, Issue 2, February 2026.
ABSTRACT Extreme conditions such as high pressure offer opportunities for innovative materials design and applications. For over a century, studies on thermal transport in crystals under high hydrostatic pressure have shown that lattice thermal conductivity generally exhibits a monotonic increase with pressure.
Zong‐Hao Yuan   +8 more
wiley   +1 more source

Janus Nanofiber‐Architected Moisture‐Enabled Power Generator for Intelligent Sensing and Neuromorphic Application

open access: yesRare Metals, Volume 45, Issue 1, January 2026.
ABSTRACT Moist‐electric generators (MEGs) harness energy from ubiquitous ambient humidity, which has emerged as a promising way to collect energy irrespective of location and time. This study presents a high‐performance MEG employing a bilayer Janus nanofiber membrane: a hydrophilic layer (lithium chloride/citric acid/polyvinyl alcohol) for enhanced ...
Peng Chen   +7 more
wiley   +1 more source

Performance improvements in complementary metal oxide semiconductor devices and circuits based on fin field‐effect transistors using 3‐nm ferroelectric Hf0.5Zr0.5O2

open access: yesRare Metals, Volume 43, Issue 7, Page 3242-3249, July 2024.
Graphical abstract AbstractIn this work, a conventional HfO2 gate dielectric layer is replaced with a 3‐nm ferroelectric (Fe) HZO layer in the gate stacks of advanced fin field‐effect transistors (FinFETs). Fe‐induced characteristics, e.g., negative drain induced barrier lowering (N‐DIBL) and negative differential resistance (NDR), are clearly observed
Zhao‐Hao Zhang   +10 more
wiley   +1 more source

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