Results 41 to 50 of about 9,130 (166)
由雷击产生的雷电过电压通常会对风-光混合发电系统中的电气设备造成严重损害,为了减少雷电过电压对风-光混合发电系统造成的危害,文中对雷电过电压进行了深入研究。在分析雷击对风-光混合发电系统暂态影响的基础上,利用PSCAD/EMTDC软件搭建了风-光混合发电系统仿真模型,通过仿真模拟雷电流侵入风-光混合发电系统的光伏发电场直流侧与风力发电场侧,研究风-光混合发电系统不同位置雷电过电压的变化情况,得到首次负雷击和后续负雷击的雷电过电压及雷电流波形。
王婉婷
doaj
Control strategy research for PV DC microgrid with hybrid storage system [PDF]
以光伏、风电等可再生能源为主的分布式发电技术因为其随机性、不稳定性,对配电网潮流改变带来的安全性等问题,其发展得到一定的制约。微电网被广泛认为是解决分布式发电技术应用瓶颈的有效解决方案,而直流微电网以直流形式传输电能,控制结构简单,不需考虑频率和相位,系统损耗小,效率高,也更加适合越来越多的直流电器的接入,因此具有很强的推广实用价值。本文在研究了直流微电网的国内外研究发展现状、架构,以及包括控制技术、储能技术、保护技术等关键技术基础上,对包含有蓄电池和超级电容器在内的光伏直流微电网系统进行了研究 ...
杨贇
core
TRPC1/TRPC3 channels mediate lysophosphatidylcholine-induced apoptosis in cultured human coronary artery smooth muscles cells [PDF]
溶血卵磷脂(lysophosphatidylcholine,lysoPC)是氧化低密度脂蛋白(oxidizedlow-densitylipoprotein,ox-LDL)的主要成分。早期的研究表明,lysoPC可诱导人冠状动脉平滑肌细胞(humancoronaryarterysmoothmusclecells,HCASMCs)凋亡,但具体机制尚不清楚。近期,我们通过细胞活力测定,流式细胞术,共聚焦显微镜及分子生物学手段对lysoPC作用的分子机制进行研究发现,lysoPC可引发细胞外钙离子内流 ...
王渊
core +1 more source
How Many Floods Have Occurred in China in the Past Decade? A Perspective From Social Media
Abstract Global climate change has led to frequent and widespread flood disasters in China. Traditional flood disaster investigations mainly focus on major flood events, and small‐scale flood events are often overlooked. This study utilized the Sina Weibo social media platform to detect flood events in 370 cities in China from 2012 to 2023.
D. Shen +5 more
wiley +1 more source
风力机非常容易受到雷电袭击,因此保证风力机安全可靠的运行至关重要,风力机雷电保护的首要步骤是分析风机雷电流分布,基于实际工程中风力发电机结构和相关运行标准,将其几何和材料参数转换为EMTP-ATP软件中的等效电路模型,计算并分析风机雷电流分布和内部过电压问题。针对由于雷电直击风机转子叶片在其内部造成的电压应力问题,通过仿真计算分析了风机电气、IT系统的多种不同类型的过电压,仿真包涵了全变流风力机的电力电子器件分析。最后根据行业标准,通过依次添加保护装置的方法提出了在风力机通信、电气系统、杆塔塔顶 ...
高参, 毛凯, 张冬谊, 蒯雷
doaj
Environmental disasters and ecomodernist beliefs: Insights from a quasi‐natural experiment
Abstract This article contributes to knowledge of how environmental disasters affect ecomodernist beliefs, i.e. the view that technology can solve environmental problems. Such beliefs in the general public are key to build mass support for environmental policies relying on large‐scale scientific solutions, but their stability is poorly understood.
Aksel Sundström
wiley +1 more source
Abstract The study investigated the effect of task complexity (TC) on second language (L2) learners’ affective responses and writing performance and how these were modulated by cognitive and affective individual difference (ID) factors. A total of 412 Chinese 8th‐grade English‐as‐a‐foreign‐language learners completed a working memory (WM) test, a scale
Chengchen Li, Li Wei, Xiaojun Lu
wiley +1 more source
为了了解大电网末端风电机组故障穿越特性,文中分析了高渗透率风力发电大电网末端电网特性及风机运行特性。结合相应的检测标准及要求,探讨了大电网末端风电并网出现的故障特性,研究了直驱及双馈风电机组故障穿越关键技术及控制策略;结合仿真及实际检测,研究了大电网末端直驱风力发电机高电压穿越能力、双馈机组低电压穿越的可行性,提出了风电机组故障穿越的隐患,为大电网稳定运行提供了依据。
李晖 +6 more
doaj
Wireless Autonomous Power Flow Control in Converter-Fed Microgrids [PDF]
When total apparent power of the energy storage system (ESS) interfacing converter is fixed, the higher the requirement on reactive power in the microgrid system with distributed multiple converters, the weaker the ability of ESS to balance theactive ...
Guerrero, Josep M. +4 more
core +2 more sources
Abstract Quality water is essential to people's health and social and economic well‐being. Evaluation of the quality of the water sources provides benchmark data on quality status and insights into the development of further protective measures. A laboratory‐based cross‐sectional study design was conducted in the diarrheal hotspot area of the North ...
Tsegahun Asfaw Abebe +5 more
wiley +1 more source

