Results 1 to 10 of about 12,711 (119)
基于ATP-EMTP的10kV配电系统不同中性点接地方式电气特性仿真分析
中性点接地方式的选择对10 k V配电系统的运行及故障处理具有重要作用。笔者据此详细阐述了10 kV配电系统中性点接地方式,并根据实际参数建立了10 k V配电系统中性点接地仿真模型,分析了不同方式下的电流电压特性,得出以下结论:小电阻接地的故障点电流远高于其他接地方式,且故障和非故障线路的零序电流差异较大,而小电流接地方式下的零序电流基本一致,对故障选线造成困难;小电阻接地方式下,工频过电压和弧光接地过电压约为不接地方式的82%、51%,可采用绝缘水平较低的电气设备,减少10 k V配电系统投资 ...
王国彬 +6 more
doaj
主动干预式消弧装置具有很强的消弧能力,是一种有效的消弧手段;中性点不接地系统运行稳定性好,但是主动干预式消弧装置在中性点不接地系统中的故障选线准确率还有待提升。针对主动干预式消弧装置在中性点不接地系统中的选线难题,分析主动干预式消弧技术原理,考虑零序电流幅值、相位特性,提出了基于零序电流矢量差的故障选线方法。在PSCAD/EMTDC平台上进行故障仿真分析,结果证明了所提出选线方法的准确性。
郝越峰
doaj
Abstract Constructed value of information (CVoI) is an expert elicitation decision‐analytic tool used to prioritize sources of uncertainty based on their potential to improve decision outcomes if resolved. Despite increased application of CVoI, the robustness of CVoI prioritization of sources of uncertainty relative to differences in expert elicitation
Kristin P. Davis +7 more
wiley +1 more source
配电网线路的对地电容不对称、所带负载大小以及检测设备所存在的误差,使得配电网中性点始终存在一定的位移电压。研究了小电流接地系统在不对称情况下发生单相接地故障的零序电流分布情况,根据现有小电流接地系统所存在的故障特征分析,提出了动态接地方式。该方式通过中性点电压位移增量以及线路零序电流的变化作为选线装置启动判据,判断故障性质后动态切换中性点接地方式,选出并切除故障线路。该方式在漯河真型试验场进行了单相接地故障检测,经试验验证得出该方式在不对称度为3%的情况下,故障电阻识别能力可达到3 500Ω ...
3.长沙信长电力科技有限公司
doaj
ABSTRACT This study examines multilingual practices in research interviews, focusing on English lexical insertions in Chinese‐language research interviews with teachers of Chinese in Australian secondary schools, and treating these code‐switches as analytically meaningful rather than incidental.
Chengwen Yuan, Tianwei Zhang, Gary Bonar
wiley +1 more source
A more‐than‐human political ecology of Indonesian songbird trade
Abstract Since its inception, conservation science has considered wildlife trade a problem. In focusing on conservation outcomes, conservationists almost completely ignore the welfare of traded animals and plants and the harms they endure. We developed a political ecology approach that incorporates the interconnectedness of people with animals and ...
Sicily Fiennes +9 more
wiley +1 more source
Abstract In the era of the sixth mass extinction, reversing global biodiversity loss is of vital importance for life on Earth. In 2022, parties to the Convention on Biological Diversity (CBD) adopted the Kunming‐Montreal Global Biodiversity Framework (GBF), a strategic plan with 23 action‐oriented targets to be achieved by 2030.
Ina Lehmann +3 more
wiley +1 more source
配电网小电阻接地方式主要存在供电可靠性低、发生高阻接地故障时选线失灵的问题。本研究将建立小电阻接地模型进行理论分析,并针对目前小电阻接地系统所出现的缺陷,提出一种经动态电阻接地方式。该方式根据三相电压、中性点电压以及各馈线零序电流之间的关系将不同单相接地故障进行分类处理。特别是在解决高阻故障时,通过动态电阻接地方式增加各馈线零序电流进解决小电阻存在的高阻选线缺陷。为验证该接地方式的有效性,在漯河真型试验场进行了现场试验。试验表明动态电阻接地方式在保留小电阻接地方式优点的同时 ...
李必伟 +4 more
doaj
ABSTRACT This paper examines the features of metadiscourse across different teacher moves in university linguistics classroom discourse and the teaching strategies reflected in its use. The results reveal that teachers employ diverse metadiscourse during classroom interactions to support student reasoning.
Jingjie Li, Wenjie Hu
wiley +1 more source
电网中性点的接地方式直接影响到电网供电的可靠性及继电保护的实施等多项指标,因此,加强对中性点接地方式的研究,将确保电力系统为适应国民经济发展的需要。本文用电网中性点接地方式模拟试验装置,作了经电阻接地的电弧接地过电压仿真试验。
张建文, 许允之
doaj

