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2011 7th Asia-Pacific International Conference on Lightning, APL2011

作者： Li, Qian Yu, Zhanqing Zeng, Rong Zhang, Yong Li, Zhizhao Zhuang, Chijie Liao, Yongli State Key Lab. of Control and Simulation of Power Systems and Generation Equipments Department of Electrical Engineering Tsinghua University Haidian District Beijing 100084 China Department of Mathematical Sciences Tsinghua University Haidian District Beijing 100084 China Electric Power Research Institute CSG Guangzhou China

ISBN: (纸本)9781457714665

Lightning is a major cause of power interruptions in power transmission lines. Nowadays the Leader Progression Model is an advanced method to evaluate the shielding failure probability of transmission lines. Calculating the surface electric field on phase conductors and ground wires precisely is important, because the surface electric field has great effect on the upward leader inception. In this paper, the influence of lightning current and some other factors on surface electric field were analyzed. © 2011 IEEE.

关键词： Electric lines

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Effects of morphology on movement of space charge packet in polyethylene

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Gaodianya Jishu/High Voltage Engineering 2008年第11期34卷 2385-2389页

作者： Zhou, Yuan-Xiang Wang, Yun-Shan Wang, Ning-Hua Sun, Qing-Hua Nie, Qiong Liang, Xi-Dong Guan, Zhi-Cheng State Key Lab. of Control and Simulation of Power Systems and Generation Equipments Dept of Electrical Engineering Tsinghua University Beijing 100084 China China Electric Power Research Institute Beijing 100085 China

Polyethylene is a major kind of internal insulating material. This paper measured the space charge phenomenon in low-density polyethylene (LDPE) by the pulsed electro-acoustic (PEA) method and observed the space charge packet. This research got the LDPE films of different morphology by different annealing rate and discussed the effect of morphology and electrical field stress changing on space charge packet's moving velocity. The research shows that morphology of LDPE affects the velocity of space charge packet remarkably;bigger crystallinity results in lower velocity of space charge packet. The intensity of electrical field has little affection to the velocity. The average mobility of different crystallinity under different electric field was calculated. The relationship between crystallinity and mobility was found. The results further demonstrate there are inherent relationships among higher crystallinity, more space charge accumulation, lower mobility and deeper trap depth. Lower mobility and deeper trap depth have a monotone relationship.

关键词：空间电荷空间电荷包聚乙烯微观形态迁移率 PEA

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Research on pilot protection applied in aircraft annular power distribution system

Research on pilot protection applied in aircraft annular pow...

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2011 International Conference on Advanced power system Automation and Protection, APAP 2011

作者： Jiang, Zhongshan Liu, Yanping Wang, Bin Dong, Xinzhou Wang, Yan Naval Aeronautical and Astronautical University Yantai 264001 China State Key Lab. of Control and Simulation of Power Systems and Generation Equipments Dept. of Electrical Engineering Tsinghua University Haidian Beijing 100084 China Beijing Wuzi University Beijing 101149 China

ISBN: (纸本)9781424496198

In the annular power distribution system, short-circuit fault of bus-bars will do fatal harm to aircraft, and it is necessary to protect the ring-net bus-bars. Protecting bus-bars has to meet the requirements that protection devices do not refuse to operate and backup protection devices do not act incorrectly. This paper builds a model about the annular power distribution system and stimulates the fault system based on MATlab. According to the fault features, directional blocking pilot protection is put forward. The results prove that the new method can achieve automatic isolation of the bus-bar at fault, ensures the safety of aircraft power distribution system, and it is of great importance to improve the reliability of aircraft power distributing. © 2011 IEEE.

关键词： MATlab

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Research on generation and execution of coordination strategy for bi-directional and interactive coordinated voltage control between provincial and district levels

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Dianwang Jishu/power system Technology 2013年第12期37卷 3426-3432页

作者： Wang, Bin Guo, Qinglai Sun, Hongbin Li, Haifeng Luo, Jianyu Zhang, Boming Wu, Wenchuan State Key Lab of Control and Simulation of Power Systems and Generation Equipments Dept. of Electrical Engineering Tsinghua University Haidian District Beijing 100084 China Jiangsu Electrical Power Dispatching and Control Center Nanjing 210024 Jiangsu Province China

To achieve the goal of bi-directional and interactive coordinated voltage control between provincial and district levels, the study is focused generation and execution of coordination strategy for bi-directional and interactive coordinated voltage control between provincial and district levels. Firstly, the method to generate the bi-directional and interactive coordination strategy between provincial and district levels is proposed, and the gateway coordination state transition diagram is designed to intuitionally express the criterion of the interaction between the AVC systems belonging to the upper and lower level systems respectively;then, the regularization method for expanded coordinated secondary voltage control suitable to provincial power network and the regularization method suitable to district power network are put forward respectively to realize mutual support between power networks in provincial level and district level. Results from simulation examples and on-site operations show that the proposed method is feasible and effective as well.

关键词： Electric power transmission networks

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Natural Frequency and Dynamic Response of Rotor system of Steam Turbine Modelled with Euler-Bernoulli Beam

Natural Frequency and Dynamic Response of Rotor System of St...

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2015 International power,Electronics and Materials Engineering Conference(IPEMEC 2015)

作者： T.T.Deng J.S.Wang X.J.Li J.L.Zhong S.B.Wang S.P.An W.G.Yang D.X.Jiang Guizhou Electric Power Test and Research Institute State Key Laboratory of Control and Simulation of Power System and Generation Equipments Department of Thermal EngineeringTsinghua University

ISBN: (纸本)9781510806474

Based on Finite element method(FEM),analysis of natural frequency and dynamics response is carried out in this ***,modeling of rotor system in steam turbines is analyzed with Euler-Bernoulli beam ***,natural frequency of the rotor system is obtained and ***,dynamic response of the rotor system is simulated and the vibration of the rotor system is *** results show that the proposed model can obtain results with high accuracy,and the model is *** modeling approach presented in this work provides a fast and accurate method in analyzing dynamic characteristics of the practical rotor system in steam turbine units

关键词： Natural frequency transient response rotor system steam turbine Euler-Bernoulli Beam

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Dynamic emergency control in digital distribution substation with MW PV power

Dynamic emergency control in digital distribution substation...

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2010 5th International Conference on Critical Infrastructure, CRIS 2010

作者： Wang, Bin Huang, Tianxiao Dong, Xinzhou Jiang, Bo Bo, Z.Q. Dept. of Electrical Engineering State Key Lab of Control and Simulation of Power Systems and Generation Equipments Tsinghua University Beijing 100084 China AREVA T and D UK Ltd. Stafford STl7 4LX United Kingdom

ISBN: (纸本)9781424480814

MW level photovoltaic generation has enough power to support the partial loads in the island operations. But the challenge is how to balance the power supply and load while the power grid is blackout, and the power supply changes to PV power. In response to this question, the anti-islanding strategy is replaced by balancing the PV output and the load shedding in paper to achieve the available maximum power balance in distribution substation. It is achieved by collecting all feeders currents (power supply and feeder outputs), which is realized in the digital substation based on IEC61850. The system scheme and the dynamic emergency control strategy to inverters in PV controller are introduced in paper. The work of the paper is valued to the research on the novel dynamic control scheme in distribution system with DGs. © 2010 IEEE.

关键词： Electric power transmission networks

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Research on HVIGBT transient mixture model and parameter extraction method

Research on HVIGBT transient mixture model and parameter ext...

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IEEE Conference and Expo Transportation Electrification Asia-Pacific (ITEC Asia-Pacific)

作者： Gaohui Feng Zhengming Zhao Liqiang Yuan Shiqi Ji Jincheng Zhao Mechanical Engineering College Shijiazhuang China State Key Laboratory of Control and Simulation of Power System and Generation Equipment Tsinghua University Beijing China

This paper presents a kind of HVIGBT transient mixture model and corresponding parameter extraction method. The HVIGBT model can divide into MOSFET and BJT two parts. The two models are formed respectively according to HVIGBT work principle, in addition, the carrier transport equations have been simplified for avoiding Kirk effect in BJT model. The transient model is realized in PSIM software in the paper. Extraction methods, which include estimation by empirical values, calculation by testing waveforms and comparison with same type models, are adopted in extracting model parameters. Through comparing testing and simulation waveforms, the model's simulation accuracy is proved.

关键词： Mathematical model Testing Semiconductor device modeling Transient analysis Insulated gate bipolar transistors Integrated circuit modeling Capacitance

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Electric Field Distribution Analysis During the Very Fast Transient Process Based on 3D Full Maxwell simulation 4th

Electric Field Distribution Analysis During the Very Fast Tr...

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4th International Conference on power and Electrical Engineering, ICPEE 2023

作者： Sun, Qiang Gao, Wensheng Zhang, Ziwei Nie, Hongyu Lu, Guiyou He, Yufeng Qu, Jiaqi Department of Electrical Engineering State Key Laboratory of Control and Simulation of Power System and Generation Equipment Tsinghua University Beijing China Sichuan Energy Internet Research Institute Tsinghua University Chengdu China Ultra High Voltage Branch State Grid Sichuan Electric Power Company Chengdu China School of Instrumentation and Optoelectronic Engineering Beihang University Beijing China

ISBN: (纸本)9789819716739

Most simulations of electric field distribution during the very fast transient (VFT) process are based on equivalent waveforms, which affects the analysis of the electric field. In this paper, the actual VFT process is simulated based on the 3D full Maxwell finite element method (FEM). The electric field distribution at different points is measured. To investigate the influence of the induced electric field during the VFT process, and whether high amplitude or high steepness is the main factor affecting insulation during the VFT process, the simulation results are compared with the electrostatic simulation results. The results show that the induced electric field caused by the wave process does not play an important part. The electric field distribution is hardly influenced by the induced electric field. Therefore, the threat to insulation caused by VFTO is mainly due to its high amplitude, which leads to a stronger Coulomb electric field. Besides, the wave process only leads to a 6~8% voltage amplitude increase, which is much lower than the amplitude increase due to externally generated low-frequency oscillations. Therefore, the high amplitude of VFTO is mainly caused by low-frequency oscillations, rather than the high-frequency components during the VFT process. © The Author(s), under exclusive license to Springer Nature Singapore Pte Ltd. 2024.

关键词： Electric fields

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Vibration Reduction by Segmented Continuous Variable Width Pole for Rotating Armature Permanent Magnet Motors

Vibration Reduction by Segmented Continuous Variable Width P...

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International Conference on Electrical Machines, ICEM

作者： Zhanlu Yang Shanming Wang Jianfeng Hong Chao Liu State Key Laboratory of Control and Simulation of Power System and Generation Equipment Tsinghua University Beijing China Navy Submarine Academy Qingdao China

ISBN: (数字)9781728199450

ISBN: (纸本)9781728199467

In order to reduce the electromagnetic vibration of rotating armature permanent magnet motor (RAPMM), this paper proposes a method to reduce vibration using the magnetic pole with segmented continuous variable width. The distribution of flux density and radial force density in air gap is calculated using analytical method. The analytical solutions of radial exciting force and bending moment exciting force on magnetic pole are obtained. Through analysis, the principle of magnetic pole width adjustment for the reduction in radial exciting force and bending moment is developed. The magnetic field, Maxwell stress, vibration deformation and acceleration of the motor are calculated using the three-dimensional finite element method. In order to validate the effectiveness of the proposed method, a comparison is performed between the proposed scheme and the other three traditional schemes. Finally, the experimental results about the four kinds of motors are compared, to validate the proposed method.

关键词： Vibrations Permanent magnet motors Prototypes Rotors Force Stator windings Permanent magnets

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Development and prospect of direct‐current circuit breaker in China

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High Voltage 2021年第1期6卷 1-15页

作者： Weijiang Chen Rong Zeng Junjia He Yi Wu Xiaoguang Wei Taixun Fang Zhanqing Yu Zhao Yuan Yifei Wu Wandi Zhou Bing Yang Lu Qu STATE GRID Corporation of China BeijingChina Department of Electrical Engineering Key Laboratory of Control and Simulation of Power System and Generation EquipmentTsinghua UniversityBeijingChina School of Electric and Electronic Engineering Huazhong University of Science&TechnologyWuhanChina School of Electrical Engineering Xi'an Jiaotong UniversityXi'anChina Global Energy Interconnection Research Institute Co. LtdBeijingChina NR Electric Co. LtdNanjingChina

The direct‐current circuit breaker(DCCB)is the most ideal choice for DC fault isolation in DC *** a late start,China's research and development on the DCCB have made outstanding *** article provides a brief glance of current China's DCCB development *** begins by sorting out the technical route according to the topology of *** it systematically summarises both mechanical and hybrid DCCBs with focussing on the aspects of topology structure and principle,key technology and characteristics,prototype development and *** is apparent that Chinese scientists and engineers confronted the worldwide problem of large capacity DC breaking,and put forward a comprehensive solution which consists of an innovative topology structure based on coupled negative voltage circuit,breaking throughs on the key technologies such as highly controllable and reliable fault current commutation,millisecond‐level ultra‐fast and efficient electromagnetic repulsion mechanism,high tolerance and high stability power electronic switch,low residual voltage and fast response energy consumption device,*** article states that the world's first set of hybrid high‐voltage(HV)DCCB,and the first set of mechanical HV DCCB have been *** DCCBs will soon be deployed to the DC grids which have the highest voltage levels therefore require the strongest breaking *** achievements are leading the world in the development and application of *** article also discusses the overall development trends of DCCB in the areas of new topologies,key techno-logical breakthroughs and application scenarios,*** discussions serve as references for DCCB's future technological advancement and its ever‐expanding applications.

关键词： breaking breakthrough discussions

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