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高压输电电流一定减小吗——一道2014年高考福建卷试题解析感悟 被引量:2
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作者 杨培军 王鹏 《物理通报》 2015年第3期103-105,共3页
远距离输电时如果采用高压输电,会减小输电线上的电流,从而减少输电线上的电压损失和电功率损失.但是对2014年福建省高考物理的一道关于远距离输电的选择题进行了详细的分析计算后,发现上述结论表述的并不准确,采用高压输电后,输电线电... 远距离输电时如果采用高压输电,会减小输电线上的电流,从而减少输电线上的电压损失和电功率损失.但是对2014年福建省高考物理的一道关于远距离输电的选择题进行了详细的分析计算后,发现上述结论表述的并不准确,采用高压输电后,输电线电流是否减小,与电路中的电阻有关. 展开更多
关键词 远距离输电 输电电阻 输电电流 功率
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一种分布式光纤多点电流传感系统 被引量:1
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作者 万雄 黄清龙 王庆 《南昌航空工业学院学报》 CAS 2001年第4期16-18,共3页
电力系统中,利用输电母线磁场的法拉第效应可研制磁光光纤电流传感模块,可在需要实时监控的节点处安放该模块,并采用波分复用(WDM)技术把所有节点的实时数据通过光纤网络汇集到中央计算机中,从而构成分布式光纤电流传感系统。
关键词 多点电流传感系统 WDM 分布式光纤传感器 法拉第效应 波分复用技术 输电电流监控
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海上油气田长距离输电应用分析 被引量:1
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作者 高璇 《船舶工程》 CSCD 北大核心 2019年第S2期66-70,151,共6页
从系统构成、拓扑结构、技术特点、经济成本等方面对高压交流输电、电流源型高压直流输电、电压源型高压直流输电技术几种常见长距离输电方式进行比选分析,重点论述各种输电方式的优缺点、在海上应用的技术方案可行性以及适用情况。工... 从系统构成、拓扑结构、技术特点、经济成本等方面对高压交流输电、电流源型高压直流输电、电压源型高压直流输电技术几种常见长距离输电方式进行比选分析,重点论述各种输电方式的优缺点、在海上应用的技术方案可行性以及适用情况。工程实际中,最优方案需根据负荷规模、输电距离、供电质量、经济成本等进行综合论证比选。在此基础上,侧重对电压源型高压直流输电在海上输电领域的应用进行分析和论证,为其在海上油气田的应用和发展提供了技术基础。作为一种新型输电方式,电压源型高压直流输电可有效提高输电距离、减小海上平台面积、提高电力系统运行可靠性和稳定性,是未来海上油气田长距离输电技术的趋势。 展开更多
关键词 长距离输电 高压交流输电 电流源型高压直流输电 电压源型高压直流输电
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220kV变电站地下电缆工频磁场长、短期变化规律分析
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作者 徐辉 宋福祥 +4 位作者 阮黎东 孙伟通 尚致楠 佟晶 李飞 《环保科技》 2016年第2期56-61,共6页
本文收集了北京地区一个典型220 k V变电站厂界处220 k V地下电缆的工频磁场自动监测系统3年的数据,通过工频磁感应强度与电流强度相关性分析及监测数据长期、短期、瞬时变化规律分析,发现工频磁感应强度与电流强度具有强相关性;且工频... 本文收集了北京地区一个典型220 k V变电站厂界处220 k V地下电缆的工频磁场自动监测系统3年的数据,通过工频磁感应强度与电流强度相关性分析及监测数据长期、短期、瞬时变化规律分析,发现工频磁感应强度与电流强度具有强相关性;且工频磁感应强度冬季高于夏季,工作日高于周末,一天中峰值出现在9~10点与18~22点;针对变化规律得出的结论可为相关的实际监测工作提供借鉴。 展开更多
关键词 地下电缆 输电电流 工频磁场 自动监测 数据分析
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基于广域测量系统的电力系统热稳定安全域 被引量:15
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作者 王菲 余贻鑫 《中国电机工程学报》 EI CSCD 北大核心 2011年第10期33-38,共6页
给出注入功率空间中满足输电线路热稳定性约束的电力系统安全域的快速计算方法。该热稳定安全域综合考虑了输电线路电流的有功和无功分量。通过有功静态安全域的数学表达式来描述输电线路有功电流与节点有功注入功率之间的数学关系;对... 给出注入功率空间中满足输电线路热稳定性约束的电力系统安全域的快速计算方法。该热稳定安全域综合考虑了输电线路电流的有功和无功分量。通过有功静态安全域的数学表达式来描述输电线路有功电流与节点有功注入功率之间的数学关系;对于输电线路的无功电流与节点无功注入功率之间的数学关系,则由"修正的关联矩阵"和基本回路矩阵描述。计算所需的全部状态变量均采用广域测量系统(wide area measurement system,WAMS)实测获得。以新英格兰39节点系统为例对该方法所确定的热稳定安全域进行校验,结果表明:由该方法所确定的热稳定安全域边界相比基于直流潮流模型的结果更精确;其计算量较采用交流潮流模型的逐点法更低。 展开更多
关键词 输电线路电流约束 直流潮流模型 有功静态安全域 热稳定安全域 广域测量系统
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500kV线路可移动直流融冰装置的研制和实现 被引量:11
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作者 冯炜 吕宏水 +1 位作者 吴维宁 朱晓东 《电力电子技术》 CSCD 北大核心 2009年第10期19-21,共3页
输电线路在冬季覆冰会对电网造成严重的破坏。针对中国典型气象条件,计算了500kV输电线路融化覆冰所需的电流,并结合该计算结果及融冰装置的使用特点,提出了实现500kV输电线路可移动直流融冰装置的技术方案。在确定技术方案及设计原则... 输电线路在冬季覆冰会对电网造成严重的破坏。针对中国典型气象条件,计算了500kV输电线路融化覆冰所需的电流,并结合该计算结果及融冰装置的使用特点,提出了实现500kV输电线路可移动直流融冰装置的技术方案。在确定技术方案及设计原则的基础上,描述了该方案的实现过程,并给出了该装置对500kV输电线路进行融冰的试验结果。结果表明该装置输出电流达到4kA,线路温升超过40℃,满足500kV输电线路的融冰需要。 展开更多
关键词 输电线路/融冰电流 直流融冰装置
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基于动态相量法的直流系统暂态响应实时快速仿真计算方法 被引量:8
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作者 王宾 李志中 董新洲 《中国电机工程学报》 EI CSCD 北大核心 2021年第5期1608-1617,共10页
为解决交流系统大扰动下电流源型直流输电(line commutate converter based HVDC,LCC-HVDC)系统电磁暂态精度响应实时求取困难的问题,该文基于动态相量法仿真框架,详细讨论了大扰动下LCC-HVDC直流输电系统的建模方案,并针对工程现场的... 为解决交流系统大扰动下电流源型直流输电(line commutate converter based HVDC,LCC-HVDC)系统电磁暂态精度响应实时求取困难的问题,该文基于动态相量法仿真框架,详细讨论了大扰动下LCC-HVDC直流输电系统的建模方案,并针对工程现场的计算精度与计算复杂度要求和逆变侧容易发生的换相失败现象,重构了易于拓展的仿真模型计算框架。多故障场景的仿真对比实验表明,与传统的动态相量仿真方案相比,所提出的框架能够准确反映直流系统在逆变侧交流系统受扰下的暂态响应特征,同时提高了计算速度,实现了LCC-HVDC系统暂态响应的高精度、实时化计算。 展开更多
关键词 电流源型直流输电 动态相量法 暂态响应 换相失败 实时仿真计算
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Organic Light-Emitting Diodes by Doping Liq into an Electron Transport Layer 被引量:1
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作者 徐维 鲁富翰 +3 位作者 蒋雪茵 张志林 朱文清 徐贵 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2008年第1期33-38,共6页
Organic light emitting diodes (OLEDs) incorporating an n-doping transport layer comprised of 8-hydroxy-quin- olinato lithium (Liq) doped into 4' 7- diphyenyl-1,10-phenanthroline (BPhen) as ETL and a p-doping tr... Organic light emitting diodes (OLEDs) incorporating an n-doping transport layer comprised of 8-hydroxy-quin- olinato lithium (Liq) doped into 4' 7- diphyenyl-1,10-phenanthroline (BPhen) as ETL and a p-doping transport layer that includes tetrafluro-tetracyano-quinodimethane (F4- TCNQ) doped into 4,4′, 4″-tris (3-methylphenylphenylamono) triphe- nylamine (m-MTDATA) are demonstrated. In order to examine the improvement in the conductivity of transport layers, hole-only and electron-only devices are fabricated. The current and power efficiency Of organic light-emitting diodes are improved significantly after introducing an n-doping (BPhen:33wt% Liq) layer as an electron transport layer (ETL) and a p-doping layer composed of m-MTDATA and F4- TCNQ as a hole transport layer (HTL). Compared with the control device (without doping) , the current efficiency and power efficiency of the most efficient device (device C) are enhanced by approximately 51% and 89% ,respectively, while driving voltage is reduced by 29%. This improvement is attributed to the improved conductivity of the transport layers that leads to efficient charge balance in the emission zone. 展开更多
关键词 P-I-N N-DOPING current efficiency electron transport CONDUCTIVITY
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Development and Prospect of China Power Grids 被引量:1
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作者 赵遵廉 《Electricity》 2004年第1期6-11,共6页
In this paper the growing process of China power grid from formation of local power grids to nationwide interconnection is reviewed. The scale and structure of power grid construction in the near future, especially th... In this paper the growing process of China power grid from formation of local power grids to nationwide interconnection is reviewed. The scale and structure of power grid construction in the near future, especially the planning on sending power from west to east, North-South supplementation and nationwide interconnection are introduced. In addition, the technologies to be extended in future grid development are briefed, such as HVDC, FACTS and compact transmission line, etc. 展开更多
关键词 power grid PLANNING in terconnection transmission technology
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Prospects for Channel Construction of Sending Power from Westto East in the Next 10 Years
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作者 张运洲 葛旭波 《Electricity》 2003年第1期6-9,共4页
This paper describes the planned power transmission from west to east through three channels. It presents the main characteristics of these three channels and the problems need to be solved.
关键词 power from west to east power transportation power construction planning
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Development of Network Interconnection in China
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作者 郑宝森 郭日彩 《Electricity》 2003年第1期30-33,共4页
This paper introduces the current situation of China power industry and interconnection, the necessity to develop interconnection, the principle of nationwide interconnection and the key technologies to be studiedincl... This paper introduces the current situation of China power industry and interconnection, the necessity to develop interconnection, the principle of nationwide interconnection and the key technologies to be studiedinclude HVDC and FACTS. The paper also discusses thefeasibility of 750 kV to be used in the northwest.regionand to speed up research and development of nighervoltage level in other regions of China, as well as scl-ence and technical innovation for transmission and dis-tribution projects. 展开更多
关键词 network interconnection west to east power transmis-sion north-south power exchang e HVDC
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Modern Travelling Wave Based Fault Location Techniques for HVDC Transmission Lines 被引量:6
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作者 陈平 徐丙垠 +1 位作者 李京 葛耀中 《Transactions of Tianjin University》 EI CAS 2008年第2期139-143,共5页
The modern travelling wave based fault location principles for transmission lines are analyzed.In order to apply the travelling wave principles to HVDC transmission lines,the special technical problems are studied.Bas... The modern travelling wave based fault location principles for transmission lines are analyzed.In order to apply the travelling wave principles to HVDC transmission lines,the special technical problems are studied.Based on this,a fault locating system for HVDC transmission lines is developed.The system can support modern double ended and single ended travelling wave princi- ples simultaneously,and it is composed of three different parts:travelling wave data acquisition and processing system,communication network and PC based master station.In the system,the fault generated transients are induced from the ground leads of the over-voltage suppression capacitors of an HVDC line through specially developed travelling wave couplers.The system was applied to 500 kV Gezhouba-Nanqiao(Shanghai)HVDC transmission line in China.Some field operation experiences are summarized,showing that the system has very high reliability and accuracy,and the maximum location error is about 3 km(not more than 0.3%of the total line length). Obviously,the application of the system is successful,and the fault location problem has finally been solved completely since the line operation. 展开更多
关键词 fault location global positioning system HVDC transmission lines REPEATERS
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Complete Localization of HVDC Back-to-Back Project Realized 被引量:1
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作者 Yu Xinqiang Liang Xuming +1 位作者 Wang Zuli Ye Qing(Translated) 《Electricity》 2006年第1期21-24,共4页
The first completely localized DC back-to-back project for asynchronous interconnection between Northwest and Central China plays an important role in realizing national power grid interconnection, spurring indigenous... The first completely localized DC back-to-back project for asynchronous interconnection between Northwest and Central China plays an important role in realizing national power grid interconnection, spurring indigenous manufacturing industries and promoting DC transmission equipment. Insisting on the principle of autonomous innovation, this project was based on domestic forces in every aspect, from engineering organization, system design, equipment completion, engineering design, equipment manufacturing and procurement to construction and debugging. By passing through strict quality control, intermediate supervision and acceptance test and assessment, the project has been proved up to world advanced level. 展开更多
关键词 power grid INTERCONNECTION BACK-TO-BACK DC converter station
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A multi-objective gravitational search algorithm based approach of power system stability enhancement with UPFC 被引量:6
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作者 Ajami Ali Armaghan Mehdi 《Journal of Central South University》 SCIE EI CAS 2013年第6期1536-1544,共9页
On the basis of the theoretical analysis of a single-machine infinite-bus (SMIB), using the modified linearized Phil- lips-Heffron model installed with unified power flow controller (UPFC), the potential of the UP... On the basis of the theoretical analysis of a single-machine infinite-bus (SMIB), using the modified linearized Phil- lips-Heffron model installed with unified power flow controller (UPFC), the potential of the UPFC supplementary controller to enhance the dynamic stability of a power system is evaluated by measuring the electromechanical controllability through singular value decomposition (SVD) analysis. This controller is tuned to simultaneously shift the undamped electromeehanical modes to a prescribed zone in the s-plane. The problem of robust UPFC based damping controller is formulated as an optimization problem according to the eigenvalue-based multi-objective function comprising the damping factor, and the damping ratio of the undamped electromechanical modes to be solved using gravitational search algorithm (GSA) that has a strong ability to find the most optimistic results. The different loading conditions are simulated on a SMIB system and the rotor speed deviation, internal voltage deviation, DC voltage deviation and electrical power deviation responses are studied with the effect of this flexible AC transmission systems (FACTS) controller. The results reveal that the tuned GSA based UPFC controller using the proposed multi-objective function has an excellent capability in damping power system with low frequency oscillations and greatly enhances the dynamic stability of the power systems. 展开更多
关键词 unified power flow controller gravitational search algorithm power system stability
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Thyristor Controlled Phase Shifter:A Comprehensive Survey
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作者 那吉.阿哈姆斯 陈珩 《Journal of Southeast University(English Edition)》 EI CAS 2001年第1期85-88,共4页
Thyristor control phase shifter (TCPS) is one of the new facilities implemented in power network, leading to the development of economically efficient and technically reliable system. This paper introduces the functio... Thyristor control phase shifter (TCPS) is one of the new facilities implemented in power network, leading to the development of economically efficient and technically reliable system. This paper introduces the function of TCPS in power system, describes its working principle and structure, and suggests some simple models used in its study and briefly presents the comparison between different types of TCPSs and their applications. 展开更多
关键词 power system FACTS TCPS phase angle regulation
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Fault location for parallel transmission lines using one-terminal current traveling waves
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作者 徐青山 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2009年第3期408-412,共5页
With proper phase module transformation,parallel lines can be decomposed to the same directional net and the reverse directional net. The propagation characteristics of traveling waves in the reverse directional net w... With proper phase module transformation,parallel lines can be decomposed to the same directional net and the reverse directional net. The propagation characteristics of traveling waves in the reverse directional net were analyzed,and the refraction coefficient at the fault point for a single phase fault was derived. In addition,the module selection was discussed. Simulation results show that satisfying accuracy can be achieved with the proposed method. Moreover,it is immune to fault types,fault resistances,and outside system parameters. 展开更多
关键词 fault location parallel transmission lines traveling wave reverse directional net
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Strong Current-Polarization and Negative Differential Resistance in FeN3-Embedded Armchair Graphene Nanoribbons
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作者 Ying-chao Wu Jia-rui Rao Xiao-fei Li 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2018年第6期756-760,733,共6页
Motivated by the recent advances of transition-metal-nitrogen-carbon (TM-N-C) materials in catalysis, we investigate the electronic structure and transport properties of FeN3-embedded armchair and zigzag graphene nano... Motivated by the recent advances of transition-metal-nitrogen-carbon (TM-N-C) materials in catalysis, we investigate the electronic structure and transport properties of FeN3-embedded armchair and zigzag graphene nanoribbons (FeN3@AGNRs, FeN3@ZGNRs) with different widths. The first-principles results indicate that the FeN3 induces significant changes on the band structures of both ZGNRs and AGNRs, making the resultant systems quite different from the pristine ones and own room-temperature stable ferromagnetic (FM) ground states. While only FeN3@AGNRs possess a significant spin-dependent negative differential resistance (NDR) and a striking current polarization (nearly 100%) behaviors, due to that FeN3 introduces two isolated spin-down states, which contribute current with different performances when they couple with different frontier orbits. It is suggested that by embedding FeN3 complexes, AGNRs can be used to build spin devices in spintronics. 展开更多
关键词 Transition-metal-nitrogen-carbon Current polarization Electronic transport Non-equilibrium Green's function
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Study on Transmission Planning of Cascade Hydropower Stations along Lancang River Basin
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作者 Cui Wenjia Du Zhongming Dai Jianfeng 《Electricity》 2012年第1期26-31,共6页
Most of the hydropower projects in Southwest China and the adjacent foreign regions will be put into operation between 2015 and 2020, which will bring some difficulties for reasonable accommodation and delivery of ele... Most of the hydropower projects in Southwest China and the adjacent foreign regions will be put into operation between 2015 and 2020, which will bring some difficulties for reasonable accommodation and delivery of electric energy. In this paper the author studies the development scale, development schedule, accommodation and transmission schemes of the cascade hydropower stations along the Lancang River basin, one of the five large basins in China, based on the load characteristics of grids at both the sending end and the receiving end, the strategy of complementary utilization of thermal power and hydropower, the advanced transmission technologies, and the optimal economic performance. The study results show that, the cascade hydropower stations on the upper reaches of the Lancang River in Yunnan should mainly serve Guangdong Province, with proper planning of partly serving Yunnan Province during dry seasons. The transmission schemes should adopt UHVDC, UHVAC, and single-tower double-circuited HVDC transmission scheme according to the transmission capacity and distance. 展开更多
关键词 hydropower station transmission scheme electric energy accommodation
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Research on Common Grounding Electrode Technique in HVDC
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作者 Chenglian MA 《International Journal of Technology Management》 2015年第1期4-6,共3页
This paper discusses the characteristics of DC transmission common system ground electrode type and shared ground electrode, established the mathematical model of two circuit DC systems share ground electrode, analyze... This paper discusses the characteristics of DC transmission common system ground electrode type and shared ground electrode, established the mathematical model of two circuit DC systems share ground electrode, analyze effects of the shared loop ground DC transmission system electrode on the operation of HVDC system size under different operation modes, and compare with the independent ground electrode, ground electrode impact on environment under different operation mode, and the paper finally puts forward some solving measures for the influence of the shared ground electrode on the environment and public ground electrode effects on DC system operation problems. 展开更多
关键词 HVDC ground electrode line protection DC transmission system TRANSIENT
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Constant Ripple Current Control for Switching DC-DC Converter
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作者 Gwo-Tarng Chern Jenn-Jong Shieh 《Journal of Energy and Power Engineering》 2012年第9期1437-1441,共5页
The adapted DC-DC converters should be smaller in size and have a small output current ripple to meet the increasing demand for low voltages with high performance and high density micro processors for several microele... The adapted DC-DC converters should be smaller in size and have a small output current ripple to meet the increasing demand for low voltages with high performance and high density micro processors for several microelectronic load applications. This paper proposes a DC-DC converter using variable on-time and variable switching frequency control enhanced constant ripple current control and reduced magnetic components. The proposed converter is realized by making the turn-offtime proportional to the on-time of the converter, according to the input and output voltage, thereby reducing the corresponding current ripple on output voltage in the continuous conduction mode. A Buck DC-DC converter using the proposed control strategy is analyzed in detail, along with some experimental results to show the performance and effectiveness of this converter. 展开更多
关键词 Constant ripple current DC-DC converter variable switching frequency continuous conduction mode indirect currentsensor magnetic component.
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