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中学生英语读写(高考版) 2003年第11期 4-5页

作者：贺育明广东

2003年8月18日,美国北部和加拿大部分地区突发电力故障。从纽约到底特律,从多伦多到魁北克,黑暗在顷刻之间降临。交通全面瘫痪,通讯联络终止,不明真相的人们惊慌失措:又一次恐怖袭击?

关键词： blackout

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blackout

大学英语 1988年第4期 32-32页

作者：刘永科

In November 1965,New York was blacked out by an *** authorities promised that it would not happen *** were certain that it would occur within five years at the *** July 1977,there was a repeat performance which produced varyingdegrees of chaos throughout the city of eight million *** 1965,the failure occurred in the cool autumn and at a time of comparative

关键词： blackout In

Mitigation of blackout problem for reentry vehicle in traveling magnetic field with induced current

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Plasma Science and Technology 2020年第12期22卷 37-47页

作者： Shaoshuai GUO Kai XIE Bin SUN Shaowei LIU School of Aerospace Science and Technology Xidian UniversityXi'an 710071People's Republic of China

In this paper, a novel solution mitigating the radio blackout problem is proposed, which improves existing traveling magnetic field(TMF)-based methods. The most significant advance lies in replacing the external injection with self-induced current, which does not require electrodes. The improved analytical model is derived to evaluate the electron density reduction taking into consideration the self-induced current for various TMF velocities. The plasma reduction performance is analyzed for several conditions including the total absence of injected current. The results show that the velocity may be used to trade off the injected current and, when sufficiently large, eliminates the need for an injected current while mitigating radio blackout. The effectiveness of this solution to the blackout problem is demonstrated in commonly used aerospace communication bands. With a field strength of less than 0.15 T, increasing the velocity from40 m s^-1 to 3100 m s^-1 is all that is required to obviate the need for an injected current. Moreover,typical reduction ratios for electronic density tolerance(2, 1.9, 1.75 and 3 times for the L-, S-, Cand X-bands, respectively, at an altitude of 40 km) remain unchanged. Increasing the velocity of the TMF is much easier than injecting current via a metal electrode into a high-temperature flow field. The TMF method appears practical in regard to possible future applications.

关键词： blackout traveling magnetic field self-induced current traveling magnetic field velocity

Texas Electric Power Crisis of 2021 Warns of a New blackout Mechanism

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CSEE Journal of Power and Energy Systems 2022年第1期8卷 1-9页

作者： Guanglun Zhang Haiwang Zhong Zhenfei Tan Tong Cheng Qing Xia Chongqing Kang State Key Laboratory of Power Systems the Department of Electrical EngineeringTsinghua UniversityBeijing 100084China

The Texas electric power crisis that occurred in February 2021 has drawn great attention internationally due to its severity and for not having been *** this rapid communication,we classify the 2021 Texas electric power crisis as an energy insufficiency-caused power crisis,which alerts of a new blackout *** from capacity insufficiencycaused power crises in the past,the Texas electric power crisis of 2021 directly resulted from the long-duration extreme cold weather as well as fundamentally from the insufficiency of sustainable supply capability of *** begin this paper with a brief retrospect of the event and its *** of energy/capacity insufficiency-caused power crises are given,as well as an overview of the supply and demand during the event,based on realistic operation *** simulations are then conducted to reveal the underlying reasons for the power crisis and reveal how to better prepare for the ***,several insights and suggestions on handling the new mode of blackout in the future are proposed and discussed.

关键词： blackout capacity insufficiency energy insufficiency power crisis Texas electric power crisis 2021

On power system blackout modeling and analysis based on self-organized criticality

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Science China(Technological Sciences) 2008年第2期51卷 209-219页

作者： MEI ShengWei XUE AnCheng ZHANG XueMin State Key Lab of Power System Department of Electrical EngineeringTsinghua UniversityBeijing 100084China Institute of Systems Science Chinese Academic of SciencesBeijing 100080China

This paper makes a comprehensive survey on power system blackout modeling and analysis based on SOC (self-organized criticality). Firstly,a generalized SOC theory from the viewpoint of cybernetics is introduced. Then the evolution model of power system and its relative mathematical description,which serves as a concrete example of the proposed generalized SOC,are given. Secondly,five blackout models capturing various critical properties of power systems in different time-scales are listed. Finally,this paper analyzes SOC in power systems,such as,the revelation of criticalities of proposed models in both micro-scale and macro-scale which can be used to assess the security of power system,and cas-cading failures process.

关键词： blackout model self-organized criticality (SOC) cascading failures

Stability Enhancement and blackout Prevention by VSC Based HVDC

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Journal of Energy and Power Engineering 2012年第11期6卷 1891-1900页

作者： Ying Jiang-Hafner Rolf Palsson Malin Agren Thomas Nordlander Pehr Hjalmarsson ManfredManchen ABB Power Systems HVDC Ludvika 77180 Sweden Power System Planning Department Nambian Power Utility Windhoek 2864 Nambian

This paper deals with the operation and performance of VSC （voltage source converter） based HVDC （high voltage direct current） interconnecting two extremely weak AC networks, the experience of Caprivilink project. It is shown in the paper that the HVDC converter automatically provides the supreme voltage and frequency stabilizing function when a critical situation is detected, no matter the disturbances appeared in sending end or receiving end AC networks. This supreme voltage and frequency stabilizing function makes it possible to avoid the blackout even if all the generators are tripped under an extra-ordinary worst contingency. By plots of recorded transients, the paper will show how the eventual blackouts are avoided.

关键词： HVDC VSC transmission system blackout weak AC system stability.

Resilience Analysis and Cascading Failure Modeling of Power Systems Under Extreme Temperatures

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Journal of Modern Power Systems and Clean Energy 2021年第6期9卷 1446-1457页

作者： Seyyed Rashid Khazeiynasab Junjian Qi IEEE Department of Electrical and Computer Engineering University of Central Florida

In this paper, we propose an AC power flow based cascading failure model that explicitly considers external weather conditions, extreme temperatures in particular, and evaluates the impact of extreme temperature on the initiation and propagation of cascading blackouts. Based on this model, resilience analysis of the power system is performed with extreme temperatures. Specifically, the changes of load and dynamic line rating are modeled due to temperature disturbance. The probabilities for transmission line and generator outages are evaluated, and the timing for each type of events is calculated to decide the actual event sequence. It should be emphasized that the correlated events, in the advent of external temperature changes, could contribute to voltage instability. Besides, we model undervoltage load shedding and operator re-dispatch as control strategies for preventing the propagation of cascading failures. The effectiveness of the proposed model is verified by simulation results on the RTS-96 3-area system. It is found that temperature disturbances can lead to correlated load change and line/generator tripping, which will greatly increase the risk of cascading and voltage instability. Critical temperature change, critical area with temperature disturbance, the identification of most vulnerable buses, and the comparison of different control strategies are also investigated.

关键词： blackout cascading failure correlation extreme temperature extreme weather power transmission reliability resilience voltage stability

FDTD Simulation on Terahertz Waves Propagation Through a Dusty Plasma

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Plasma Science and Technology 2016年第8期18卷 798-803页

作者：王茂琰张猛李桂萍姜宝钧张小川徐军 School of Physical Electronics University of Electronic Science and Technology of ChinaChengdu 610054China The 41st Institute of China Electronics Technology Group Corporation Qingdao 266555China

The frequency dependent permittivity for dusty plasmas is provided by introducing the charging response factor and charge relaxation rate of airborne particles. The field equations that describe the characteristics of Terahertz（THz） waves propagation in a dusty plasma sheath are derived and discretized on the basis of the auxiliary differential equation（ADE） in the finite difference time domain（FDTD） method. Compared with numerical solutions in reference, the accuracy for the ADE FDTD method is validated. The reflection property of the metal Aluminum interlayer of the sheath at THz frequencies is discussed. The effects of the thickness, effective collision frequency, airborne particle density, and charge relaxation rate of airborne particles on the electromagnetic properties of Terahertz waves through a dusty plasma slab are ***, some potential applications for Terahertz waves in information and communication are analyzed.

关键词： Terahertz dusty plasma finite-difference time-domain (FDTD) blackout

Optimized dispatch of wind farms with power control capability for power system restoration

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Journal of Modern Power Systems and Clean Energy 2017年第6期5卷 908-916页

作者： Yunyun XIE Changsheng LIU Qiuwei WU Kairong LI Qian ZHOU Minghui YIN School of Automation Nanjing University of Science and TechnologyNanjing 210094China Department of Electrical Engineering Centre for Electric Power and EnergyTechnical University of DenmarkKgs.2800LyngbyDenmark Electric Power Research Institute of State Grid Jiangsu Electric Power Company Nanjing 211103China

As the power control technology of wind farms develops,the output power of wind farms can be constant,which makes it possible for wind farms to participate in power system ***,due to the uncertainty of wind energy,the actual output power can’t reach a constant dispatch power in all time intervals,resulting in uncertain power sags which may induce the frequency of the system being restored to go outside the security ***,it is necessary to optimize the dispatch of wind farms participating in power system *** that the probability distribution function(PDF)oftransient power sags is hard to obtain,a robust optimization model is proposed in this paper,which can maximize the output power of wind farms participating in power system *** results demonstrate that the security constraints of the restored system can be kept within security limits when wind farm dispatch is optimized by the proposed method.

关键词： blackout Dispatch optimization of wind farm Power control of wind farm System restoration Uncertainty of wind energy

Reflections on stability technology for reducing risk of system collapse due to cascading outages

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Journal of Modern Power Systems and Clean Energy 2014年第3期2卷 264-271页

作者： Yongjie FANG NARI Group Corporation Nanjing 211106China

This paper aims at putting forward viewpoints regarding the use of stability technology to prevent and control cascading outages by examining recent blackout *** on the inquiry reports of the 2011 SouthwestAmerica blackout and the 2012 India power blackouts,event evolution features are first summarized from a stability *** a comparative analysis is conducted so as to propose suggestions of effective measures,either preventive or emergency,which could have avoided the *** is shown that applications of several mature technologies can create opportunities of preventing or interrupting the cascading *** include offline dynamic simulation,online stability analysis and preventive control,real-time situational awareness and automatic emergency *** R&D directions are given to address the challenges of modern power systems as *** cover system fault identification criterion of protection and control devices,verification of adaptability of control effect to system operating conditions,real-time operational management of emergency control measures and improvement of simulation accuracy.

关键词： Cascading outages blackout System collapse Stability technology Protection and control