检索结果-内蒙古大学图书馆

International Conference on Electrical Machines and systems (ICEMS)

作者： Xinzhen Wu Xiangheng Wang Department of Electrical Engineering State Key Laboratory of Control and Simulation of Power Systems and Generation Equipment Tsinghua University Beijing China

ISBN: (纸本)7506274078

To evaluate the rotor bar parameters of an induction machine with the non-sinusoidal current, a new analysis approach, which employs the circuit analysis theory instead of electromagnetic field theory to count the skin effect, is proposed. In the presented method, a rotor bar is divided into many thin-layers with their own parameters derived. The superposition principle is proven for the calculation of total bar losses and slot magnetic energy due to the non-sinusoidal current composed of sinusoidal components with different frequencies, which shows the parameters of the bar can be expressed with the parameters at respective frequencies. For given examples, the parameters at different frequencies are calculated, and the results are verified by the analytical method or the finite element method.

关键词： Induction machines Skin effect Frequency Rotors Electromagnetic analysis Circuit analysis Magnetic losses Magnetic analysis Finite element methods power system simulation

来源：评论

学校读者我要写书评

暂无评论

Optimized design of main protection configuration scheme for internal faults of Shawan generator

Optimized design of main protection configuration scheme for...

引用

International Conference on Electrical Machines and systems (ICEMS)

作者： Yuguang Sun Xiangheng Wang Lin Gui Weijian Wang Department of Electrical Engineering State Key Laboratory of Control and Simulation of Power Systems and Generation Equipment Tsinghua University Beijing China

ISBN: (纸本)7506274078

In order to provide high-quality protection for large- and medium-sized generators, a new feasible method of designing main protection configuration scheme for internal faults of generators is desirable. Based on calculation of all the possible internal faults with the multi-loop method, the optimized design method is illustrated through Shawan generator in this paper. With this method, the optimal protection configuration scheme, composed of the split-phase transverse differential protection, two sets of incomplete longitudinal differential protection as well as one set of single element transverse differential protection, is determined for the internal faults of Shawan generator, which has two branches in each phase. The rate of operation and double-protection of the optimal scheme both reach the maximum. In addition to that, on all the possible phase-to-phase faults, at least two kinds of protection of the optimal scheme are sure to operate correctly. The optimized scheme excels the conventional one in protection performance index, which verifies the validity of the optimized method of designing main protection configuration scheme for generators.

关键词： Design optimization Circuit faults Design methodology power generation power system protection Character generation power system simulation Performance analysis Stators Sun

来源：评论

学校读者我要写书评

暂无评论

Aging effect of UV radiation on SIR insulators' hydrophobicity property

Aging effect of UV radiation on SIR insulators' hydrophobici...

引用

Conference on Electrical Insulation and Dielectric Phenomena, (CEIDP)

作者： Xun Wang Xidong Liang Yuanxiang Zhou State Key Laboratory of Control and Simulation of Power System and Generation Equipment Department of Electrical Engineering Tsinghua University Beijing China

ISBN: (纸本)0780385845

Based on the simulation of ultraviolet (UV) radiation in the Sun's rays and in corona, the aging effect of UV radiation on composite insulators was studied in this paper, especially the effect on hydrophobicity properties. It is found that after irradiation with UV, no matter whether a short time of less than 24 hours or a long time of 2000 hours, the hydrophobicity and the hydrophobicity transfer properties of silicone rubber (SIR), which are described by contact angle, slowly turns better. Four different kinds of samples with different prescriptions were used in the test. As UV sources, a special setup to simulate the UV rays of corona and a xenon light to simulate the sunlight were both used. The change of rigidity of silicone rubber was also measured. Infrared spectra of the silicone rubber surface, irradiated by UV for various times, show that the content of the low molecule weight on the surface is different, and this can be due to the discrepancy of hydrophobicity properties of the samples.

关键词： Aging Testing Slabs Xenon Corona Rubber power system simulation Surface cleaning Dielectrics and electrical insulation Stress

来源：评论

学校读者我要写书评

暂无评论

Influence of annealing method on the space charge properties in polyethylene

Influence of annealing method on the space charge properties...

引用

Conference on Electrical Insulation and Dielectric Phenomena, (CEIDP)

作者： Ninghua Wang Yuanxiang Zhou Hongbin Liu Bin Gao Xidong Liang Zhicheng Guan T. Takada State Key Laboratory of Control and Simulation of Power System and Generation Equipment Tsinghua University Beijing China Electronic Measurement Laboratory Musashi Institute of Technology Tokyo Japan

In this paper, high-density polyethylene (HDPE) films were prepared by three kinds of annealing methods which were different in cooling speed. The crystallinity of those HDPE samples were measured and compared. A high DC voltage was applied to the samples and the space charge formed was measured. Homo-charges were found in samples that were applied with a negative high voltage. The space charge properties were discussed, based on crystallinity. From these results, it is found that the space charge formed in samples cooled at high speed is more than that of the samples cooled at normal and low speed.

关键词： Annealing Space charge Polyethylene Voltage Current measurement Charge measurement Conducting materials Crystallization Morphology Laboratories

来源：评论

学校读者我要写书评

暂无评论

Research and development of the vacuum type dejectas collecting device on high-speed train

Research and development of the vacuum type dejectas collect...

引用

World Congress on Intelligent control and Automation (WCICA)

作者： Jiajun Lou Mingguang Wu Fan Ding National Laboratory of Industrial Control Technology Institute of System Engineering University of Zhejiang Hangzhou China State Key Laboratory of Fluid power Transmission and Control Mechtronics and Control Engineering University of Zhejiang Hangzhou China

Firstly the increasing domestic demand and the developing situation of dejectas collecting device were analyzed briefly. A new design of the vacuum type dejectas collecting device was contrived. Then its structural ch... 详细信息

ISBN: (纸本)0780382730

关键词： Research and development Laboratories Industrial control power engineering and energy systems engineering and theory power transmission control systems control engineering Testing

来源：评论

学校读者我要写书评

暂无评论

Human systems integration and advanced technology in engineering department workload and manpower reduction

引用

NAVAL ENGINEERS JOURNAL 2003年第1期115卷 57-65页

作者： Lively, KA Seman, AJ Kirkpatrick, M KENNETH A. LIVELY graduated from the University of Colorado with a BS in applied mathematics and an MS in mathematics in 1976 and from the Massachusetts Institute of Technology with an MS in electrical engineering and the degree ocean engineer in naval architecture and marine engineering in 1984. He retired from the U.S. Navy in 1989 after 23 years of service. Assignments included electrical officer on the USS Constellation (CV 64) project engineer for the DDG 51 machinery control system (NAVSEA) and DDG 51 Technical Director (NAVSEA). He was vice president of the PDI Division of Bird-Johnson Company from July 1989 to November 1998 where he managed various gas turbine and machinery controls related development projects. He joined Anteon Corporation's Systems Engineering Group as senior controls engineer in December 1998 where he provided technical support to the integrated power systems program (NAVSEA PMS 510) and managed the Office of Naval Research Afloat Laboratory. DR. MARK KIRKPATRICK is currently an independent consultant in human factors and work-load/manning analysis and modeling. He holds a Ph.D. degree in experimental psychology from The Ohio State University and has 34 years of experience in applied human factors. From 1982 through 2000 Dr. Kirkpatrick served as the senior vice president of Carlow International. Prior to joining Carlow in 1982 Dr. Kirkpatrick served as a member of the technical staff at North American Rockwell's Missiles Division and as a project director and vice president for Essex Corporation. His areas of expertise include workload simulation task analysis operator-in-the-loop simulation human performance experimentation statistical analysis and human factors T&E. He has directed and/or participated in human factors projects for the U.S. Navy U.S. Army NASA Department of Transportation the U.S. Nuclear Regulatory Commission and private industry. ANTHONY J. SEMAN III is the technical manager for the reduced ship's crew by virtual presence (RSVP) advanced technology d

Aboard current ships, such as the DDG 51, engineering control and damage control activities are manpower intensive. It is anticipated that, for future combatants, the workload demand arising from operation of systems under conditions of normal steaming and during casualty response will need to be markedly reduced via automated monitoring, autonomous control, and other technology initiatives. Current DDG 51 class ships can be considered as a manpower baseline and under Condition III typical engineering control involves seven to eight watchstanders at manned stations in the Central control Station, the engine rooms and other machinery spaces. In contrast to this manning level, initiatives such as DD 21 and the integrated engineering plant (IEP) envision a partnership between the operator and the automation system, with more and more of the operator's functions being shifted to the automation system as manning levels decrease. This paper describes some human systems integration studies of workload demand reduction and, consequently, manning reduction that can be achieved due to application of several advanced technology concepts. Advanced system concept studies in relation to workload demand are described and reviewed including. Piecemeal applications of diverse automation and remote control technology concepts to selected high driver tasks in current DDG 51 activities. Development of the reduced ship's crew by virtual presence system that will provide automated monitoring and display to operators of machinery health, compartment conditions, and personnel health. The IEP envisions the machinery control system as a provider of resources that are used by various consumers around the ship. Resource needs and consumer priorities are at all times dependent upon the ship's current mission and the availability of equipment pawnbrokers.

关键词： Naval warfare

来源：评论

学校读者我要写书评

暂无评论

Digital power system

Digital power system

引用

World Congress on Intelligent control and Automation (WCICA)

作者： Lu Qiang State Key Laboratory of Control and Simulation of Power Systems and Generation Equipments China

The concept of a digital power system (DPS) is set forth in the paper. The definition, the contents, the function, the hardware and the software conditions for implementing it are discussed. Moreover, the necessary basic research work for implementing a DPS is also discussed. The DPS may be defined like this: the digital power system is the digital, figuration and real time description and reappearance of physical structure, technical characteristic, management system as well as personal information system of a real power system which is in operation. The DPS will be able to make a significant contribution to administrating and decision-making more scientifically, improving security and stability online, online making and implementing economical operation strategy and carrying out emergency and anti-fault control, etc.

关键词： power system control

来源：评论

学校读者我要写书评

暂无评论

Extended load-flow arithmetic for voltage stability analysis

Extended load-flow arithmetic for voltage stability analysis

引用

International Conference on power system Technology (powerCON)

作者： L. Zhu S. Zhou Y. Zhang State Key Laboratory of Control and Simulation of Power Systems and Generation Equipment Tsinghua University Beijing China

ISBN: (纸本)0780363388

In this paper, a novel load-flow arithmetic for voltage stability analysis is studied where models of various dynamic elements in power systems are taken into account. It simultaneously solves the load flow equation and the state equation of dynamic elements and gets both the voltage amplitude, phase of all buses and the inner state variables of the dynamic elements. In this arithmetic different limits are considered and the assumption of PV bus, PQ bus and slack bus are eliminated, so the result is closer to the real operation condition. Using a flow arithmetic based on continuation-power-flow (CPF) method, the critical point of voltage stability of the system can be computed. The proposed method is demonstrated on a test system and the results are compared with the conventional power flow method.

关键词： Arithmetic Voltage Stability analysis power system dynamics power system modeling Load flow Equations power system analysis computing power system stability system testing

来源：评论

学校读者我要写书评

暂无评论

Two-stage EEG source reconstruction by using the layered recursive algorithm and source contracting method

Two-stage EEG source reconstruction by using the layered rec...

引用

作者： Zou, J. Xie, Y.Q. Dong, G.Y. State Key Lab of Control and Simulation of Power Systems and Generation Equipments Department of Electrical Engineering Tsinghua University Beijing 100084 China School of Physics Peking University Beijing China Prov.-Min. Joint Key Laboratory of Electromagnetic Field and Electrical Apparatus Reliability Department of Electrical Engineering Hebei University of Technology Tianjin 300130 China

A two-stage electroencephalogram (EEG) source tomography method is proposed. First, the layer recursive algorithm (LRA) is developed to calculate the cortical potentials from the scalp potentials by using the finite volume method, which can improve spatial resolution of EEG data and be called high-resolution EEG (HIEEG). As a result, the spatial resolution is improved over that obtained with the conventional EEG. Second, the source contracting method is used to localize the equivalent electrical sources inside the brain based on HIEEG data. The applications demonstrate the effectiveness of the method proposed. The LRA provides an alternative implementation to HIEEG. © 2006 IEEE.

关键词： Electroencephalography

来源：评论

学校读者我要写书评

暂无评论

Creating multivariable response surfaces by the two-stage adaptive sampling techniques and its application in the optimization of grounding grids

Creating multivariable response surfaces by the two-stage ad...

引用

作者： Zou, J. Guo, J. Zhang, B. He, J.L. Lee, J. Chang, S. State Key Laboratory of Control and Simulation of Power Systems and Generation Equipments Department of Electrical Engineering Tsinghua University Beijing 100084 China Electrical Environment and Transmission Group Korea Electrotechnology Research Institute Changwon 641600 Korea Republic of

A fast and efficient adaptive sampling algorithm to obtain the response surface of multivariable objective function is presented. The algorithm is divided into two stages. First, starting with a low-rank interpolation model, the technique systematically increases the rank by optimally choosing new support points in the areas of the highest error until the required accuracy is achieved. Second, the verification between the fitted result and the exact one is carried out. The optimization of grounding grids is performed to show the effectiveness of the proposed algorithm. © 2006 IEEE.

关键词： Algorithms

来源：评论

学校读者我要写书评

暂无评论

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案：

请选择收藏分类：

通借通还

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：