检索结果-内蒙古大学图书馆

Asia-Pacific Symposium on Electromagnetic Compatibility (APEMC)

作者： Zhiyong Wang Shaoan Wang Zhanqing Yu Yinan Geng Rong Zeng Jinliang He Zhizhao Li Guangzhou Power Supply Bureau China Southern Power Grid Company Limited Guangzhou China Department of Electrical Engineering State Key Laboratory of Control and Simulation of Power Systems and Generation Equipments Tsinghua University Beijing China

ISBN: (纸本)9781424456215

Shielding failure of lightning is the key problem for safe operation of UHV transmission lines. Taking the feature of 1000KV AC double circuit transmission lines into account, the leader progression method with proper criterion was employed. The lightning shielding failure rate of top phase, middle phase and bottom phase of two different transmission line tower types were compute, in three different geography conditions. The research work is helpful for improving the lightning performance of UHV transmission lines.

关键词： Failure analysis Lightning Distributed parameter circuits Conductors power transmission lines Transmission line theory Voltage Corona Poles and towers power system simulation

来源：评论

学校读者我要写书评

暂无评论

Tests on electromagnetic environment of ultra HVDC transmission lines in high altitude region

Tests on electromagnetic environment of ultra HVDC transmiss...

引用

Asia-Pacific Symposium on Electromagnetic Compatibility (APEMC)

作者： Zhanqing Yu Rong Zeng Min Li Ruihai Li Lei Liu Bo Zhang Zheng Zhang Huaying Zhang State Key Laboratory of Control and Simulation of Power Systems and Generation Equipments Department of Electrical Engineering Tsinghua University Beijing China Technology Research Center China Southern Power Grid Company Limited China

ISBN: (纸本)9781424456215

The Ultra High Voltage DC power transmission technique is developed quickly in China but used barely in the world. Corona phenomenon in high altitude region is more serious, and corresponding electromagnetic environment is more severe as well. A UHVDC test lines are completed for tests in Kunming, China, with an altitude of 2100 m. An automotive electromagnetic environment testing system was installed under the line. Measurement of electromagnetic environment was carried out. Radio interference, audible noise, resultant electric field and ion current density at ground level were measured at different voltage from ±800kV to ±1000kV, and atmosphere conditions including sunny, rainy and cloudy weather. The measured result show some difference with those acquired at sea level and is significant for further studies of corona mechanism under high altitude condition. Measured results were compared with the calculated results.

关键词： HVDC transmission Atmospheric measurements Sea measurements Electromagnetic measurements Voltage Corona power transmission Automotive engineering System testing Electromagnetic interference

来源：评论

学校读者我要写书评

暂无评论

Radio interference of Ultra HVDC transmission lines in high altitude region

Radio interference of Ultra HVDC transmission lines in high ...

引用

Asia-Pacific Symposium on Electromagnetic Compatibility (APEMC)

作者： Zhanqing Yu Rong Zeng Min Li Ruihai Li Lei Liu Dawei Yang Zheng Zhang Bo Zhang Feng Tian State Key Laboratory of Control and Simulation of Power Systems and Generation Equipments Department of Electrical Engineering Tsinghua University Beijing China Technology Research Center China Southern Power Grid Company Limited China

ISBN: (纸本)9781424456215

Corona phenomenon of Ultra High Voltage DC in high altitude region is more serious, and corresponding electromagnetic environment is more severe as well. Radio Interference is the most important consideration during the design and operation. Characteristics of RI and its influence factors were studied based on an UHVDC test line with an altitude of 2100 m in the National Engineering laboratory for UHV Technology, located in Kunming, China. The measuring system of RI long term tests was introduced. Lateral and longitudinal distribution and spectrum of RI near the transmission line were analysed at various voltages, weather conditions.

关键词： Electromagnetic interference HVDC transmission Voltage Corona Testing power transmission lines DC generators Conductors Transmission line measurements Electromagnetic compatibility

来源：评论

学校读者我要写书评

暂无评论

Protection of microgrid

Protection of microgrid

引用

10th IET International Conference on Developments in power System Protection (DPSP 2010). Managing the Change

作者： Shenxing. Shi Bo. Jiang Xinzhou. Dong Zhiqian. Bo State Key Laboratory of Control and Simulation of Power System and Generation Equipments Tsinghua University China AREVA T and D Inc. Stafford UK

The paper analyses the existed protection of microgrid. And in order to meet the requirements of microgrid protection, a novel protection is presented in this paper. The protection based on local information without the need of communication, uses current traveling waves to identify faulted feeder, and the bus bar voltages to determine a event caused by fault or switch operation. In the protection scheme, current traveling waves are measured by current transducers in N line and phase lines, and wavelet multi-resolution analysis is used to decompose traveling wave signals. The initial traveling waves are compared in magnitude and polarity with each other to determine the faulted feeder. The protection is independent of microgrid operation connected with the main power grid or in island.

关键词：

来源：评论

学校读者我要写书评

暂无评论

A Pi-based control scheme for primary cascaded H-bridge rectifier in transformerless traction converters

A Pi-based control scheme for primary cascaded H-bridge rect...

引用

International Conference on Electrical Machines and systems (ICEMS)

作者： Tao Xinghua Li Yongdong Sun Min Department of Electrical Engineering Naval University of Engineering China State Key Laboratory of Control and Simulation of Power System and Generation Equipments Department of Electrical Engineering Tsinghua University China

Cascaded H-Bridge rectifier (CHBR) is a more attractive solution in traction application for its transformerless structure. Because of the currents of different cells are exactly the same one, it is a challenge job to regulate the voltages of cells with only one current controller. In this paper, a PI-based control scheme is presented to deal with the voltages balance issue in CHBR. To satisfy the demand of rectifier such as unity power factor and regulated output DC voltages, the proposed control scheme consists of two parts. One is for shaping the grid current waveform and regulating the sum of DC-link voltages of all the cells; the other one is for balancing DC-link voltages. The latter is more concerned in this paper and is discussed in detail especially. simulations and experiments are carried on. The results verified the feasibility and effectiveness of the proposed scheme.

关键词： Rectifiers Voltage control Voltage measurement Converters Pulse width modulation Mathematical model

来源：评论

学校读者我要写书评

暂无评论

state of the art of hybrid excitation permanent magnet synchronous machines

State of the art of hybrid excitation permanent magnet synch...

引用

作者： Wang, Shanming Xia, Yonghong Wang, Xiangheng Su, Pengsheng Huang, Shaogang Zhang, Anming State Key Laboratory of Control and Simulation of Power System and Generation Equipments Department of Electrical Engineering Tsinghua University Beijing 100084 China Department of Electrical and Automatic Engineering Nanchang University Nanchang Jiangxi 330031 China Military Deputy Department Dalian 426 Factory No.1 Yanhai Jie Xigang Qu Dalian Liaoning 116005 China

ISBN: (纸本)9788986510119

The hybrid excitation permanent magnet machine (HEPMM) combines two kinds of excitation: permanent magnet (PM) and electrical excitation, so it possesses the advantages of PM machines and overcomes the incapability of regulating the excitation field. By now many HEPMM schemes have been presented. In this paper the operation principle, structure, advantages and disadvantages of these HEPMMs have been reviewed and compared in detail. These HEPMMs are classified into three types by new classification method - placement of PM and iron poles. At last novel harmonic excitation HEPMM is proposed and discussed.

关键词： Permanent magnets

来源：评论

学校读者我要写书评

暂无评论

Analysis of cutting-edge techniques in the high voltage and high power adjustable speed drive systems

引用

Science China(Technological Sciences) 2009年第2期52卷 442-449页

作者： ZHAO ZhengMing BAI Hua YUAN LiQiang State Key Laboratory of Control and Simulation of Power System and Generation Equipment Department of Electrical EngineeringTsinghua UniversityBeijing 100084China

The high voltage and high power adjustable speed drive (ASD) system is one of the most attractive fields in power electronics, and it is also a very crucial technique for energy saving and emission reduction. This paper discussed and analyzed the main cutting-edge knowledge and issues in the process of exploiting the high voltage and high power ASD system.

关键词： high voltage and high power inverter safe operation area pulse and pulse sequence

来源：评论

学校读者我要写书评

暂无评论

state of the art of hybrid excitation permanent magnet synchronous machines

State of the art of hybrid excitation permanent magnet synch...

引用

2010 International Conference on Electrical Machines and systems, ICEMS2010

关键词： Iron Magnetic fields Windings Stator cores Rotors Stator windings Magnetic circuits

来源：评论

学校读者我要写书评

暂无评论

Nanosecond-pulse Dielectric Barrier Discharge Using Magnetic Compression Solid-state Pulsed power

Nanosecond-pulse Dielectric Barrier Discharge Using Magnetic...

引用

IEEE International power Modulator and Hogh Voltage Conference

作者： Tao Shao Yang Yu Cheng Zhang Zheng Niu Dongdong Zhang Jue Wang Yaohong Sun Ping Yan Yuanxiang Zhou Institute of Electrical Engineering Chinese Academy of Sciences State Key Laboratory of Control and Simulation of Power Systems and Generation Equipments Electrical Engineering Department Tsinghua University

ISBN: (纸本)9781424471317

Dielectric barrier discharge excitated by unipolar pulsed power is a promising approach for producing non-thermal plasma at atmospheric pressure. A magnetic compression solid-state pulse power generator is used to produce dielectric barrier discharge (DBD). The generator is capable of providing repetitive pulses with the voltage of up to 30 kV and duration of 70 ns at a 300 Ω resistive load. This paper illustrates electrical characteristic and luminous emissions of DBD excitated by repetitive unipolar nanosecond-pulses in atmospheric air. Different from common DBD excitated by high-voltage AC sources, discharge current of DBD in the experimental investigation can be on an order of tens of amperes. When the DBD is created using two liquid electrodes, the luminous emissions from the obverse and flank sides of liquid electrodes show that no filament is observed and the discharge is homogeneous and diffuse in the whole discharge regime.

关键词： Dielectric barrier discharge Pulsed power Magnetic compression Repetitive nanosecond pulses Atmospheric pressure air Gas discharge Homogeneous discharge

来源：评论

学校读者我要写书评

暂无评论

IGBT modeling for analysis of complicated multi-IGBT circuits

IGBT modeling for analysis of complicated multi-IGBT circuit...

引用

2009 2nd Conference on power Electronics and Intelligent Transportation System, PEITS 2009

作者： Deng, Yi Zhao, Zhengming Yuan, Liqiang State Key Laboratory of Control and Simulation of Power System and Generation Equipment Department of Electrical Engineering Tsinghua University Beijing China

ISBN: (纸本)9781424442461

A new IGBT (Insulated Gate Bipolar Transistor) model for simulation of eomplicated multi-IGBT cireuits is presented. Based on the gate chargc and discharge behaviors of IGBT, it piecewise models the turn-on and -off transient oflGBT, and simulates the static characteristics with curve fitting method . With the kcy features of high simulation spccd, easy parameters extraction and clear physical meaning, the model is available for various IGBTs and system level circuits. This paper describes the structure and equivalent circuit of the model in detail, implements it with the simulation tool of PSIM package, and determines the parameters of the model for an IGBT of FF300R12ME3 as an example. The accuracy of the model is verified by the comparison between the simulated and experimental results. ©2009 IEEE.

关键词： Equivalent circuits

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：