期刊文献+
共找到371篇文章
< 1 2 19 >
每页显示 20 50 100
Earth energy evolution, human development and carbon neutral strategy 被引量:5
1
作者 ZOU Caineng MA Feng +6 位作者 PAN Songqi LIN Minjie ZHANG Guosheng XIONG Bo WANG Ying LIANG Yingbo YANG Zhi 《Petroleum Exploration and Development》 CSCD 2022年第2期468-488,共21页
Energy is the basis of human development and the impetus of society progress. There are three sources of energy: energy of celestial body outside the Earth, the Earth energy and energy of interaction between the Earth... Energy is the basis of human development and the impetus of society progress. There are three sources of energy: energy of celestial body outside the Earth, the Earth energy and energy of interaction between the Earth and other celestial bodies. Meanwhile, there are three scales of co-evolution: the evolution of the Sun-Earth-Moon system on an ultra-long time scale has provided energy sources and extra-terrestrial environmental conditions for the formation of the Earth system;the evolution of the Earth system on a long time scale has provided the material preconditions such as energy resources and suitable sphere environment for life birth and the human development;on a short time scale, the development of human civilization makes the human circle break through the Earth system, expanding the extraterrestrial civilization. With the co-evolution, there are three processes in the carbon cycle: inorganic carbon cycle, short-term organic carbon cycle and long-term organic carbon cycle, which records human immoderate utilization of fossil energy and global sphere reforming activities, breaking the natural balance and closed-loop path of the carbon cycle of the Earth, causing the increase of greenhouse gases and global climate change, affecting human happiness and development. The energy transition is inevitable, and carbon neutrality must be realized. Building the green energy community is a fundamental measure to create the new energy system under carbon neutrality target. China is speeding up its energy revolution and developing a powerful energy nation. It is necessary to secure the cornerstone of the supply of fossil energy and forge a strong growing pole for green and sustainable development of new energy. China energy production and consumption structure will make a revolutionary transformation from the type of fossil energy domination to the type of new energy domination, depending on a high-level self-reliance of science and technology and a high-quality green energy system of cleaning, low-carbon, safety, efficiency and independence. Energy development has three major trends: low-carbon fossil energy, large-scale new energy and intelligent energy system, relying on the green innovation, contributing the green energy and constructing the green homeland. 展开更多
关键词 energy evolution earth system human civilization carbon neutrality carbon cycle global climate change technological innovation energy power
下载PDF
Progress, challenge and significance of building a carbon industry system in the context of carbon neutrality strategy 被引量:3
2
作者 ZOU Caineng WU Songtao +7 位作者 YANG Zhi PAN Songqi WANG Guofeng JIANG Xiaohua GUAN Modi YU Cong YU Zhichao SHEN Yue 《Petroleum Exploration and Development》 2023年第1期210-228,共19页
Carbon dioxide storage and utilization has become an inevitable trend and choice for sustainable development under the background of global climate change and carbon neutrality.Carbon industry which is dominated by CO... Carbon dioxide storage and utilization has become an inevitable trend and choice for sustainable development under the background of global climate change and carbon neutrality.Carbon industry which is dominated by CO_(2) capture,utilization and storage/CO_(2) capture and storage(CCUS/CCS)is becoming a new strategic industry under the goal of carbon neutrality.The sustainable development of carbon industry needs to learn from the experiences of global oil and gas industry development.There are three types of“carbon”in the earth system.Black carbon is the CO_(2) that has not been sequestered or used and remains in the atmosphere for a long time;grey carbon is the CO_(2) that has been fixed or permanently sequestered in the geological body,and blue carbon is the CO_(2) that could be converted into products for human use through biological,physical,chemical and other ways.The carbon industry system covers carbon generation,carbon capture,carbon transportation,carbon utilization,carbon sequestration,carbon products,carbon finance,and other businesses.It is a revolutionary industrial field to completely eliminate“black carbon”.The development of carbon industry technical system takes carbon emission reduction,zero carbon,negative carbon and carbon economy as the connotation,and the construction of a low-cost and energy-efficient carbon industry system based on CCUS/CCS are strategic measures to achieve the goal of carbon neutrality and clean energy utilization globally.This will promote the“four 80%s”transformation of China's energy supply,namely,to 2060,the percentage of zero-carbon new energy in the energy consumption will be over 80%and the CO_(2) emission will be decreased by 80%to ensure the carbon emission reduction of total 80×10^(8) t from the percentage of carbon-based fossil energy in the energy consumption of over 80%,and the percentage of CO_(2) emission from energy of over 80%in 2021.The carbon industry in China is facing three challenges,large CO_(2) emissions,high percentage of coal in energy consumption,and poor innovative system.Three strategic measures are proposed accordingly,including:(1)unswervingly develop carbon industrial system and ensure the achievement of carbon neutrality as scheduled by 2060;(2)vigorously develop new energy sources and promote a revolutionary transformation of China’s energy production and consumption structure;(3)accelerate the establishment of scientific and technological innovation system of the whole CO_(2) industry.It is of great significance for continuously optimization of ecological environment and construction of green earth and ecological earth to develop the carbon industry system,utilize clean energy,and achieve the strategic goal of global carbon neutrality. 展开更多
关键词 carbon industry system carbon neutrality carbon sequestration green earth carbon footprint carbon trade peak carbon dioxide emission dual carbon target
下载PDF
Application of Fault Location Mode Based on Travelling Waves for Neutral Non-effective Grounding Systems
3
作者 Tao Ji Qian-qian Yuan +2 位作者 Chang-ming Li Ying Sun (Scientific Research Office Weifang University Weifang,China College of Information and Electrical EngineeringShandong University of Science and Technology Qingdao,China) 《Journal of Measurement Science and Instrumentation》 CAS 2010年第S1期133-138,共6页
Fault location for distribution feeders short circuit especially single-phase grounding fault is an important task in distribution system with non-effectively grounded neutral.Fault location mode for distribution feed... Fault location for distribution feeders short circuit especially single-phase grounding fault is an important task in distribution system with non-effectively grounded neutral.Fault location mode for distribution feeders using fault generated current and voltage transient traveling waves was investigated.The characteristics of transient traveling waves resulted from each short circuit fault and their transmission disciplinarian in distribution feeders are analyzed.This paper proposed that double end travelling waves theory which measures arriving time of fault initiated surge at both ends of the monitored line is fit for distribution feeders but single end traveling waves theory not.According to different distribution feeders,on the basis of analyzing original traveling waves reflection rule in line terminal, Current-voltage mode,voltage-voltage mode and current-current mode for fault location based on traveling waves are proposed and aerial mode component of original traveling waves is used to realize fault location.Experimental test verify the feasibility and correctness of the proposed method. 展开更多
关键词 distribution feeders neutral non-effective grounding traveling waves fault locationmode
下载PDF
Over Voltage Fault due to Disconnection of Consumer’s Transformer Neutral Wire
4
作者 Erdene Adiyasuren Enkh-Od Erdene +1 位作者 Sergelen Byambaa Shagdarsuren Gantumur 《Journal of Energy and Power Engineering》 2023年第1期11-14,共4页
Practically,the load currents in three phases are asymmetric in the power system.It means that the impedances are different in all three phases.If the consumer’s transformer neutral cut off and/or was disconnected fr... Practically,the load currents in three phases are asymmetric in the power system.It means that the impedances are different in all three phases.If the consumer’s transformer neutral cut off and/or was disconnected from the neutral of power supply source,then there will be some trouble and failure occurred.The current in the neutral wire drops down to zero when the neutral wire is cut off and the phase currents of all three-phase equal to each other since there was no return wire.The currents are equal but the voltages at the phase consumers are different.Especially for residential single-phase consumers,the voltage at the consumers of the phase varies differently for three phase systems when the neutral wire was disconnected at consumer side and even the voltage at the consumers one or two of those three phases becomes over nominal voltage or reaches nearly line voltage.In this case,the electronic appliances in that phase will be fed by high voltage than the rated value and they can be broken down.In the power system of UB(Ulaanbaatar)city,there are some occasional such kind of failures every year.Obviously,many electronic appliances were broken down due to high voltage and the electricity utility companies respond for service charge of damaged parts. 展开更多
关键词 neutral connection and neutral wire phase and line voltage single-phase residential consumer transformer neutral cut off asymmetric load current protective earth
下载PDF
从离子型稀土镁盐富集物中提取稀土工艺初探 被引量:1
5
作者 柯兆华 郭安 +5 位作者 邱小英 廖春生 蓝桥发 葛刘生 肖莉 黄德晟 《有色金属(冶炼部分)》 CAS 北大核心 2024年第1期61-67,共7页
以MgO为沉淀剂沉淀MgSO_(4)稀土浸出母液时,得到的稀土镁盐富集物REO总量较低,需要进一步除去杂质以沉淀富集稀土。以离子型稀土镁盐富集物为原料,进行碳化—酸溶—中和除杂—沉淀等工艺初步探索研究。结果表明:REO在碳化过程中的损失... 以MgO为沉淀剂沉淀MgSO_(4)稀土浸出母液时,得到的稀土镁盐富集物REO总量较低,需要进一步除去杂质以沉淀富集稀土。以离子型稀土镁盐富集物为原料,进行碳化—酸溶—中和除杂—沉淀等工艺初步探索研究。结果表明:REO在碳化过程中的损失很少甚至可以忽略不计,有24.33%~30.9%MgO由稀土镁盐富集物转化进入碳化后液,在中和除杂过程中Fe去除率约99.5%,Al去除率约98.6%。以碳化后液为沉淀剂沉淀中和除杂后液得到碳酸稀土,经过灼烧,获得了符合《GB/T 20169—2015离子型稀土矿混合稀土氧化物》标准质量要求的稀土氧化物,该工艺总渣率为19.81%~23.22%,REO总收率平均89.43%。为了从离子型稀土镁盐富集物中提取稀土的工艺形成成套工艺技术,获取最优的工艺技术参数,有待于后续深入研究和优化。 展开更多
关键词 稀土镁盐富集物 碳化 酸溶 中和除杂 沉淀 总收率
下载PDF
矿山供电系统单相接地故障区段定位方法
6
作者 史鹏飞 张龙飞 +2 位作者 何俊涛 李凯歌 刘鹏辉 《能源与环保》 2024年第4期165-171,共7页
中性点非有效接地的矿山高压供电系统发生单相接地故障后,故障暂态过程交叉干扰严重,故障信号呈现出很强的非线性、非平稳性、高时变性和复杂性,故障定位难度很大。针对此难题,提出了一种基于分布散度的故障区段定位方法。首先,通过等... 中性点非有效接地的矿山高压供电系统发生单相接地故障后,故障暂态过程交叉干扰严重,故障信号呈现出很强的非线性、非平稳性、高时变性和复杂性,故障定位难度很大。针对此难题,提出了一种基于分布散度的故障区段定位方法。首先,通过等效电路分析了故障特性,研究并采用Choi-Williams分布(Choi-Williams Distribution,CWD)时频能量谱克服故障信号中多频率成分交叉干扰。然后,采用改进KL散度表征故障区段上下游信号时频分布差异,处理上下游信号CWD时频能量谱中重叠部分,消除故障区段上下游信号相似成分的不利影响。在此基础上,借助零序电流信号CWD-KL散度构建了故障定位判据。最后,仿真测试与对比分析验证了所提方法的有效性与优越性。 展开更多
关键词 矿山供电系统 中性点非有效接地 单相接地故障 分布散度 故障定位
下载PDF
一起10 kV单相接地引发三相短路故障的辨识与分析
7
作者 李航 《农村电气化》 2024年第9期60-64,共5页
针对一起10 kV中性点非有效接地系统中由单相接地引发两相异地接地短路,最终发展为三相短路的事故案例,通过故障录波及现场故障信息情况进行辨识分析,得出了故障原因,并提出了防范措施及建议。
关键词 10 kV中性点非有效接地系统 单相接地 三相短路
下载PDF
面向高电缆化率配电网的中性点接地技术探讨
8
作者 李昌林 沈宗正 +1 位作者 周楦颉 何才松 《通信电源技术》 2024年第10期61-63,共3页
随着城镇化的飞速发展,配电网系统的电缆比例不断提高,电缆开始逐渐替代传统的架空线路。然而,现有许多变电站的中性点接地方式仍基于纯架空线路设计,难以适应高电缆化率配电网系统的需求。文章针对配电网中性点接地方式进行了系统研究... 随着城镇化的飞速发展,配电网系统的电缆比例不断提高,电缆开始逐渐替代传统的架空线路。然而,现有许多变电站的中性点接地方式仍基于纯架空线路设计,难以适应高电缆化率配电网系统的需求。文章针对配电网中性点接地方式进行了系统研究,详细阐述其类型、特性以及对电力系统的作用。针对高电缆化率配电网,提出中性点接地方式的选择建议,为保障配电网的安全稳定运行提供参考。 展开更多
关键词 配电网 中性点接地方式 故障选线 高电缆化率 消弧线圈并联小电阻
下载PDF
Major biological events and fossil energy formation: On the development of energy science under the earth system framework 被引量:2
9
作者 PAN Songqi ZOU Caineng +8 位作者 LI Yong JING Zhenhua LIU Entao YUAN Ming ZHANG Guosheng YANG Zhi WU Songtao QIU Zhen LIU Hanlin 《Petroleum Exploration and Development》 CSCD 2021年第3期581-594,共14页
In geological history, one major life explosion and five mass extinction events occurred. These major biological and environmental events affected the evolution of the Earth ecosystem and controlled the formation of o... In geological history, one major life explosion and five mass extinction events occurred. These major biological and environmental events affected the evolution of the Earth ecosystem and controlled the formation of organic-rich strata. The life explosion occurred in Cambrian and the five mass extinction events happened at the end of Ordovician, Late Devonian, end of Permian, end of Triassic, and end of Cretaceous, respectively. They are corresponded to the formation of multiple suites of organic-rich strata globally, which are crucial to the formation, evolution and distribution of the fossil energy on Earth. China’s energy is characterized by "unlimited new energy, rich in coal but insufficient in oil and gas ", and it is determined to rely on new energy sources to achieve " energy independence " and carbon neutrality. From the perspective of the Earth system evolution, we investigate the multiple relationships between energy and Earth, energy and environment, as well as energy and human beings, and carry out comprehensive research on energy. Energy science refers to the science of studying the various energy sources formation and distribution, evaluation and selection, production and utilization, orderly replacement, development prospects, etc. in temporal and spatial scales based on the evolution of the Earth system. The connotation of energy science includes three core contents:(1) The relationship between the Earth and energy, including the formation of energy in the Earth system and the feedback of energy consumption to the Earth’s climate and environment;(2) The relationship between the Earth environment and the human beings, including the Earth environment breeding human beings and human activities transforming the earth environment;(3) The relationship between the energy and the human beings, including the development of energy technology by human beings and the progress of human society driven by energy utilization. The energy science focuses on the formation and development of fossil energy, development and orderly replacement of new energy, exploration and utilization of energy in deep earth and deep space, and energy development strategy and planning. The proposal of energy science is of great significance for improving the discipline system, promoting energy development, clarifying the development direction of energy transition, driving the carbon neutral geology research and constructing a habitable Earth. 展开更多
关键词 life explosion mass extinction carbon neutral fossil energy new energy energy development strategy earth habitability energy science
下载PDF
Estimate Totel Number of the Earth Atmospheric Particle with Standard Atmosphere model
10
作者 GAOChong-Yi 《Communications in Theoretical Physics》 SCIE CAS CSCD 2001年第5期639-640,共2页
The total number of atmospheric particle (AP) is an important datum for planetary science and geoscience. Estimating entire AP number is also a familiar question in general physics. With standard atmosphere model, con... The total number of atmospheric particle (AP) is an important datum for planetary science and geoscience. Estimating entire AP number is also a familiar question in general physics. With standard atmosphere model, considering the number difference of AP caused by rough and uneven in the earth surface below, the sum of dry clean atmosphere particle is . So the whole number of AP including water vapor is . The rough estimation for the total number of AP on other planets (or satellites) in condensed state is also discussed on the base of it. 展开更多
关键词 planetary atmosphere earth atmosphere neutral atmosphere total number of atmospheric particle standard atmosphere model effect of uneven in the earth surface estimation
下载PDF
碳中和战略背景下建设碳工业体系的进展、挑战及意义 被引量:20
11
作者 邹才能 吴松涛 +7 位作者 杨智 潘松圻 王国锋 姜晓华 管墨迪 于聪 于志超 沈月 《石油勘探与开发》 SCIE EI CAS CSCD 北大核心 2023年第1期190-205,共16页
全球气候变化与碳中和背景下,CO_(2)封存利用已成为人类绿色发展的必然趋势与选择。以CO_(2)捕集、利用与封存/CO_(2)捕集与封存(CCUS/CCS)为核心的碳工业,正成为碳中和目标下的新兴战略产业,规模可持续发展需借鉴全球油气工业发展路径... 全球气候变化与碳中和背景下,CO_(2)封存利用已成为人类绿色发展的必然趋势与选择。以CO_(2)捕集、利用与封存/CO_(2)捕集与封存(CCUS/CCS)为核心的碳工业,正成为碳中和目标下的新兴战略产业,规模可持续发展需借鉴全球油气工业发展路径。地球系统发育3种“碳”,黑碳是未被封存或利用并长期留存在大气圈中的CO_(2),灰碳是被固定或永久封存在地质体中的CO_(2),蓝碳是通过生物、物理、化学等方式可转化为人类利用产品的CO_(2)。碳工业体系覆盖碳产生、碳捕集、碳运输、碳利用、碳封存、碳产品、碳金融等业务,是彻底消除“黑碳”的革命性领域。研发以碳减排、零碳、负碳及碳经济为内涵的碳工业技术体系,构建以CCUS/CCS为基础的低成本、高能效的碳工业体系,是世界各国实现碳中和目标和能源清洁利用的战略举措,利于推动4个“80%”的中国能源供应格局转变,即由2021年含碳化石能源消费占比80%以上、化石能源CO_(2)排放80%以上,转变为2060年非碳新能源占比80%以上、CO_(2)排放减少80%以上,保障实现80×108t碳减排总量与碳中和战略目标。中国碳工业发展面临CO_(2)排放量偏大、煤炭占比偏高和创新体系偏弱3方面挑战,针对性提出3条应对举措:(1)坚定不移开展碳工业体系建设,保障2060年前如期实现碳中和;(2)大力发展新能源,推动中国能源生产与消费结构实现革命性转换;(3)加快建立全产业的碳工业科技创新体系。发展碳工业体系,利用清洁化能源,实现全球碳中和战略目标,对持续优化生态环境、构建绿色地球与生态地球意义重大。 展开更多
关键词 碳工业体系 碳中和 碳汇 绿色地球 碳足迹 碳交易 碳达峰 双碳目标
下载PDF
碳中和背景下干打垒遗产建筑保护性改造策略研究
12
作者 姜伟 唐晓英 +2 位作者 刘功良 郭巍 刘桂德 《城市建筑》 2023年第11期176-178,共3页
在碳中和背景下,对大庆市红旗村干打垒遗产建筑的安全性及能源消耗进行分析,发现现有的干打垒遗产建筑存在诸多结构安全问题及运营期能源消耗过大的现象。基于保护性改造原则,提出干打垒建筑基础、抗震性能、墙体表面等安全改造策略,围... 在碳中和背景下,对大庆市红旗村干打垒遗产建筑的安全性及能源消耗进行分析,发现现有的干打垒遗产建筑存在诸多结构安全问题及运营期能源消耗过大的现象。基于保护性改造原则,提出干打垒建筑基础、抗震性能、墙体表面等安全改造策略,围护结构节能改造、太阳能间接式与纵轴风涡轮机发电两者互补的采暖系统改造策略。改造后可作为石油文化旅游景点和干打垒精神传承基地,与大庆其他石油工业文化遗产相结合,形成一条完整的大庆精神展示路线,构成大庆特有的石油文化遗产旅游新廊道。 展开更多
关键词 干打垒遗产建筑 干打垒精神 碳中和 改造策略
下载PDF
黄土高原碳汇系统研究展望 被引量:2
13
作者 洪增林 成星 +2 位作者 张瑜 陈清敏 曾忠诚 《西北地质》 CAS CSCD 北大核心 2023年第3期39-50,共12页
全球温度升高1.2℃,应对气候变化已经到了刻不容缓的地步。2019年9月,中国政府承诺中国在2030年碳达峰,在2060年碳中和,这是一份巨大担当,也是一个巨大的挑战。碳中和的达成需要节能减排,还需要负排放技术和增加生态、地质碳汇。能源结... 全球温度升高1.2℃,应对气候变化已经到了刻不容缓的地步。2019年9月,中国政府承诺中国在2030年碳达峰,在2060年碳中和,这是一份巨大担当,也是一个巨大的挑战。碳中和的达成需要节能减排,还需要负排放技术和增加生态、地质碳汇。能源结构的调整和CCUS等负排放技术的发展需要几十年的时间,亟需要调查和研究生态和地质碳汇的现状并且增加碳汇潜力。全球范围的碳汇清查主要依靠“自上而下”和“自下而上”的估算方法,而国家级别的区域碳汇清查目前还是一个难点。黄土高原是最早起步进行退耕还林还草生态工程的地区,也是生态脆弱区。目前,黄土高原区域的碳汇调查和研究尚属于起步阶段。基于国家“双碳”战略需要和黄土高原生态文明建设,笔者从地球系统科学角度,回溯黄土高原的碳汇调查研究成果,总结黄土高原区域碳汇评估的方法体系,包含有机碳汇系统和无机碳汇系统。其中,有机碳汇系统包含有机质碳储量子系统和生态碳汇子系统的研究;无机碳汇系统主要包含碳酸盐碳汇系统和硅酸盐碳汇系统。在此基础上,从地球系统科学角度提出黄土高原碳汇调查研究建议。 展开更多
关键词 黄土高原 碳中和 生态碳汇 农田土壤碳汇 无机碳汇 地球系统科学
下载PDF
基于碳中和愿景下的干打垒遗产公园规划设计研究
14
作者 刘功良 姜伟 +2 位作者 唐晓英 郭巍 刘桂德 《江西建材》 2023年第9期106-107,110,共3页
干打垒建筑作为大庆的重要工业遗产,承载着大庆油田开发的文化历史。但由于保护不利,干打垒建筑遭受不同程度的破坏,为让干打垒建筑再次焕发生气,传播其因陋就简、艰苦创业的“干打垒精神”价值。文中以红旗村干打垒建筑群为基址,基于... 干打垒建筑作为大庆的重要工业遗产,承载着大庆油田开发的文化历史。但由于保护不利,干打垒建筑遭受不同程度的破坏,为让干打垒建筑再次焕发生气,传播其因陋就简、艰苦创业的“干打垒精神”价值。文中以红旗村干打垒建筑群为基址,基于碳中和愿景下,通过合理的规划策略与规划要点将其打造为干打垒遗产公园。将干打垒被动式保护转变成主动式保护性开发利用,使其焕发青春,促进大庆市从“油”到“游”的经济转型。 展开更多
关键词 干打垒 碳中和 遗产公园 规划设计
下载PDF
基于异常电压分析的110 kV线路单相断线故障快速判别及防治 被引量:1
15
作者 袁士超 贺旭 +2 位作者 李巨山 蔡振华 张洪磊 《黑龙江电力》 CAS 2023年第4期300-304,313,共6页
110 kV线路单相断线故障是一种发生概率较小、容易忽视,但在当前高质量供电背景和建设安全可控新型电力系统要求下,属于后果严重的故障类型。以浙江某地区110 kV输电线路单相断线故障为例,从原理上分析该类故障现象的成因。基于故障情... 110 kV线路单相断线故障是一种发生概率较小、容易忽视,但在当前高质量供电背景和建设安全可控新型电力系统要求下,属于后果严重的故障类型。以浙江某地区110 kV输电线路单相断线故障为例,从原理上分析该类故障现象的成因。基于故障情况下电源侧和负荷侧的异常电压分析,提出110 kV单相断线故障快速判别方法,将判据与实际案例对比,结果一致。分析了断线发生原因并提出防治建议,便于今后调度、运维人员准确判别、有效防治该类故障。 展开更多
关键词 单相断线 中性点接地系统 内桥接线
下载PDF
A Novel Single Phase Grounding Fault Protection Scheme Without Threshold Setting for Neutral Ineffectively Earthed Power Systems 被引量:9
16
作者 Xiangjun Zeng Kun Yu +1 位作者 Yuanyuan Wang Yao Xu 《CSEE Journal of Power and Energy Systems》 SCIE 2016年第3期73-81,共9页
The setting values of thresholds for fault feature parameters are critical in all kinds of protection schemes.When the detected feature parameter value exceeds the setting value,the protection will trip.However,the se... The setting values of thresholds for fault feature parameters are critical in all kinds of protection schemes.When the detected feature parameter value exceeds the setting value,the protection will trip.However,the setting value based conventional protection schemes sometimes cannot satisfy the protection requirements of neutral ineffectively earthed power systems(NIEPS)due to wide variations in operating conditions and the complexities of fault cases.In this paper,a novel single phase grounding fault protection scheme without threshold setting is proposed.The fault detection is achieved based on operating states rather than setting values.A fuzzy c-means algorithm is used to divide the operating state of the protected feeder into non-fault states and fault states.The cluster center of each state is then obtained by classifying the historical feature samples of the protected feeder extracted under various operating conditions into their corresponding states in a constructed multi-dimensional fault feature space.The distances between the detected feature samples and the cluster centers of the non-fault and the fault states are calculated.If the distance to the fault state is shorter than that to the non-fault state,a fault is detected.Otherwise,the feeder is considered normal.A PSCAD/EMTDC simulator is used to simulate a 35 kV NIEPS under various operating conditions,non-linear loads,and complex fault cases.Results show that the proposed single phase grounding fault protection scheme without threshold setting can protect the system correctly under all kinds of faults. 展开更多
关键词 Distribution networks FCM algorithm neutral ineffectively earthed power systems protection scheme without threshold setting
原文传递
Fault Feeder Identification in Non-effectively Grounded Distribution Network with Secondary Earth Fault 被引量:1
17
作者 Shu Zhang Tianlei Zang +1 位作者 Wenhai Zhang Xianyong Xiao 《Journal of Modern Power Systems and Clean Energy》 SCIE EI CSCD 2021年第5期1137-1148,共12页
Secondary earth faults occur frequently in power distribution networks under harsh weather conditions.Owing to its characteristics,a secondary earth fault is typically hidden within the transient of the first fault.Th... Secondary earth faults occur frequently in power distribution networks under harsh weather conditions.Owing to its characteristics,a secondary earth fault is typically hidden within the transient of the first fault.Therefore,most researchers tend to focus on a feeder with single fault while disregarding secondary faults.This paper presents a fault feeder identification method that considers secondary earth faults in a non-effectively grounded distribution network.First,the wavelet singular entropy method is used to detect a secondary fault event.This method can identify the moment at which a secondary fault occurs.The zero-sequence current data can be categorized into two fault stages.The first and second fault stages correspond to the first and secondary faults,respectively.Subsequently,a similarity matrix containing the time-frequency transient information of the zero-sequence current at the two fault stages is defined to identify the fault feeders.Finally,to confirm the effectiveness and reliability of the proposed method,we conduct simulation experiments and an adaptability analysis based on an electromagnetic transient program. 展开更多
关键词 Secondary earth fault non-effectively grounded distribution network wavelet singular entropy similarity matrix zero-sequence current
原文传递
城市轨道交通中性点不接地供电系统单相接地保护新方案
18
作者 刘爱华 《电气化铁道》 2023年第S02期148-154,共7页
通过对城市轨道交通中性点不接地供电系统中不同位置发生单相接地故障时的对地电容电流进行分析,提出了对应的保护新方案。文中明确了该保护方案的系统配置、保护定值设置及相应的控制逻辑,并对控制逻辑进行了验证。
关键词 中性点不接地 单相接地故障 方向零序电流保护 GOOSE 控制逻辑
下载PDF
高压断路器T100a开断试验最后电流半波参数及TRV参数计算
19
作者 何宁辉 万华 +3 位作者 薛飞 吴慧 张佩 马奎 《哈尔滨理工大学学报》 CAS 北大核心 2023年第3期67-73,共7页
非对称短路故障开断试验T100a是高压交流断路器型式试验的重要试验项目,中性点非有效接地系统中的断路器首开极系数为1.5,暂态恢复电压(TRV)具有两参数或四参数特征。通过建立T100a开断试验短路电流和电压表达式,分析与计算了中性点非... 非对称短路故障开断试验T100a是高压交流断路器型式试验的重要试验项目,中性点非有效接地系统中的断路器首开极系数为1.5,暂态恢复电压(TRV)具有两参数或四参数特征。通过建立T100a开断试验短路电流和电压表达式,分析与计算了中性点非有效接地系统中首开大半波和延长大半波情况下的三相开断过程,进一步计算了两种情况下首开极和晚开两极的最后电流半波参数及TRV参数。并分别以额定电压40.5 kV和额定电压126 kV断路器进行T100a开断试验为例计算了最后电流半波参数和TRV参数,计算结果为断路器的开断试验提供考核依据。 展开更多
关键词 中性非有效接地系统 T100a 电流零点 最后电流半波 TRV
下载PDF
稀土冶炼分离废水中和渣分析研究
20
作者 庄辉 潘江涛 刘国干 《山西冶金》 CAS 2023年第8期47-48,51,共3页
简要介绍了稀土冶炼分离生产废水的来源,对酸性废水中和渣成分进行试验分析得出,废水中和渣水分质量分数约占60%以上、碳酸钙镁质量分数为8.1%~15.3%等都是造成中和渣量大的主要原因,造成后续生产成本的增加。针对以上原因提出了优化工... 简要介绍了稀土冶炼分离生产废水的来源,对酸性废水中和渣成分进行试验分析得出,废水中和渣水分质量分数约占60%以上、碳酸钙镁质量分数为8.1%~15.3%等都是造成中和渣量大的主要原因,造成后续生产成本的增加。针对以上原因提出了优化工艺流程及其他改进措施,可有效降低废水中和渣数量。 展开更多
关键词 稀土 废水 中和渣
下载PDF
上一页 1 2 19 下一页 到第
使用帮助 返回顶部