检索结果-内蒙古大学图书馆

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

来源：评论

学校读者我要写书评

暂无评论

Development and prospect of direct‐current circuit breaker in China

引用

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

来源：评论

学校读者我要写书评

暂无评论

ANALYSIS OF THE MULTI-MODE OSCILLATIONS OF OFFSHORE WIND FARMS 18

ANALYSIS OF THE MULTI-MODE OSCILLATIONS OF OFFSHORE WIND FAR...

引用

18th International Conference on AC and DC power Transmission, ACDC 2022

作者： Fan, Yupeng Dong, Wenkai Li, Peng Qin, Yi Jiang, Haojie Xie, Xiaorong Datang Guoxin Binhai Offshore Wind Power Generation Co. Ltd Jiangsu Province Yancheng224000 China State Key lab of Control and Simulation of Power Systems and Generation Equipment Dept. of Electric Engineering Tsinghua University Beijing100084 China China Datang Corporation Science and Technology General Research Institute Ltd Beijing100040 China

ISBN: (数字)9781839537615

ISBN: (纸本)9781839537615

Multi-mode oscillation (MMO) is more prone to happen in the offshore wind farm (OWF) than the onshore, which seriously impacts the safe operation of the system. In this paper, the mechanism for the MMO of the OWF is analytically studied. First, the impedance model (IM) of a grid-connected OWF is derived with the AC submarine cable modelled as a distributed parameter circuit (DPC). Second, since the DPC of N n sections can be approximately seen as composed of N identical capacitances in daisy-chain connection, based on the consistent control theory for homogeneous systems, the IM of the DPC is decoupled into N subsystems, each of which is composed of a x circuit. The IM of the DPC is the weighted sum of the IMs of the N subsystems. As each x circuit has one tip (jump between ±90°) in the amplitude(phase)-frequency characteristics (APFC), the IM of the cable will have N tips (jumps) in the APFC and is much more prone to intersect with the IM of the OWF. Thus, resonance is more likely to happen at multiple frequency points. Finally, effectiveness of the methods proposed and conclusions drawn is validated via study cases. © ACDC 2022. All rights reserved.

关键词： Offshore wind farms

来源：评论

学校读者我要写书评

暂无评论

Vulnerability Assessment Based on Operational Reliability Weighted and Preventive Planning

Vulnerability Assessment Based on Operational Reliability We...

引用

Sustainable power and Energy Conference (iSPEC)

作者： Ning Qi Lin Cheng Yi Jiang Jinshan Luo Ke Sun Dan Wang Weiyuan Wang Wentao Sun State Key Lab. of Control and Simulation of Power System and Generation Equipment Tsinghua University Beijing China State Grid Jiangsu Economic Research Institute Jiangsu China

Vulnerability assessment is the key to the security and stability analysis of power system. During the operation of power grid, the fault risk of electrical equipment is not fixed because of the influence of system operating conditions, operating environment and equipment itself, so the vulnerability of power system will also be changeable. Based on the existing research results of complex network theory, a vulnerability assessment method considering operational reliability is proposed in this paper. Firstly, the basic idea of reliability weighted vulnerability assessment is introduced. Then HITS algorithm and PageRank algorithm will be used to analyze the basic vulnerability of power grid topology. Moreover, the vulnerability index of power grid considering reliability weighted is calculated. Finally, numerical analysis focusing on the difference between basic and improved assessment method is tested in IEEE RTS-79 system, and the preventive planning suggestions will be given based on the vulnerability assessment results.

关键词：

来源：评论

学校读者我要写书评

暂无评论

Research on Lithium-ion Battery Safety Risk Assessment Based on Measured Information

Research on Lithium-ion Battery Safety Risk Assessment Based...

引用

2020 IEEE Sustainable power and Energy Conference, iSPEC 2020

作者： Zhou, Xuyan Cheng, Lin Wan, Yuxiang Qi, Ning Tian, Liting You, Feng State Key Laboratory of Control and Simulation of Power Systems and Generation Equipments Tsinghua University Beijing China Energy Storage System Business Unite Tianjin Lishen Battery Joint-Stock Co. Ltd. Tianjin China

ISBN: (纸本)9781728191645

Lithium-ion batteries have the advantages of high energy density, fast power response, recyclability, and convenient to movement, which are unsurpassed by other energy storage systems. However, safety issues such as thermal runaway of lithium-ion batteries have become the main bottlenecks restricting the development of their extensive applications. In practical applications, the demand for battery energy storage scale and specific energy continues to increase, and the contradiction between battery high safety and battery safety has become increasingly prominent. This paper proposes a lithium-ion battery safety risk assessment method based on online information. Effective predictions are essiential to avoid irreversible damage to the battery and ensure the safe operation of the battery energy storage system before a failure occurs. This paper is expected to provide novel risk assessment method and research idea for the development and design of high-safety battery systems. © 2020 IEEE.

关键词： Lithium-ion batteries

来源：评论

学校读者我要写书评

暂无评论

Investigation of bipolar block emergency in UHVDC convertor station caused by lightning stroke

Investigation of bipolar block emergency in UHVDC convertor ...

引用

2012 31st International Conference on Lightning Protection, ICLP 2012

作者： Zhang, Xiao Yu, Zhanqing He, Jinliang Luo, Bin Cai, Hansheng State Key Laboratory of Control and Simulation of Power System and Generation Equipments Department of Electrical Engineering Tsinghua University Beijing 100084 China Xipeng Chen Technology Research Centre China Southern Power Grid Co. Ltd Guangzhou Guangdong Province China

ISBN: (纸本)9781467318976

It is noteworthy that bipolar block emergencies of the ±800kV UHVDC system in China happened twice within two years caused by lightning strokes. To recur and investigate the mechanism of such emergencies, lightning transient performance and relative electromagnetic interference (EMI) in the UHVDC system are investigated. Wide-band circuit models of major UHVDC equipments are set for calculation, while the lightning stroke shielding failure process and transmission corona loss are also considered during the simulation. By combining the fault records in the converter station and simulation results , possible ways of EMI into the secondary system produced by primary circuit lightning transient are analyzed. The results would help explain the cause of such bipolar block emergency and provide reference for protection methods of lightning caused EMI in UHVDC system. © 2012 IEEE.

关键词： Lightning

来源：评论

学校读者我要写书评

暂无评论

Basic reason for the accumulation of charge on the surface of polymer dielectrics

引用

Science China Materials 2022年第10期65卷 2884-2888页

作者： Tianyu Wang Xiaofen Li Boya Zhang Dayu Li Jianbo Liu Guixin Zhang State Key Laboratory of Control and Simulation of Power System and Generation Equipment Department of Electrical EngineeringTsinghua UniversityBeijing 100084China Key Laboratory of Advanced Materials(MOE) School of Materials Science and EngineeringTsinghua UniversityBeijing 100084China State Key Laboratory of Electrical Insulation and Power Equipment Xi’an Jiaotong UniversityShaanxi 710049China

Due to their outstanding electrical insulation performance,low energy loss and high reliability,polymer dielectrics are widely used in flexible electronics,capacitors and large-scale power transmission equipment[1–5].However,polymer dielectrics accumulate large amounts of charge on their surface during use,which causes local electric field distortion and induces flashover,explosion,and equipment damage[6–9].Although researchers have attempted to develop methods to reduce the accumulation of surface charge through material modification,such as plasma treatment[10],direct fluorination[11],and coating[7,9,12],each of these methods has drawbacks;thus,the bottleneck has yet to be overcome.

关键词：电荷量第一性原理计算聚合物表面电介质电场畸变深能级缺陷电荷测量电荷特性

来源：评论

学校读者我要写书评

暂无评论

Modeling and analysis of secondary controlled virtual synchronous generator with dynamic droop for microgrid

Modeling and analysis of secondary controlled virtual synchr...

引用

2017 IEEE Conference on Energy Internet and Energy system Integration, EI2 2017

作者： Yan, Weihang Gao, David Wenzhong Zhang, Fang Cheng, Lin Yan, Shijie Department of Electrical and Computer Engineering University of Denver Denver United States State Key Laboratory of Control and Simulation of Power Systems and Generation Equipment Tsinghua University Beijing China College of Information Science and Technology Northeastern University Shenyang China

ISBN: (纸本)9781538614273

In this paper, a dynamic droop mechanism is proposed to damp the synchronizing oscillation that exists in a virtual synchronous generator based distributed generator system without varying the steady-state active-power-loop droop coefficient. In order to eliminate the steady-state error introduced due to load changes or generator trips, a distributed secondary controller based on extremum seeking is employed so that microgrid frequency can be restored to nominal value. Besides, the small-signal model of virtual synchronous generator system is presented under d-q reference frame where virtual synchronous generator is deployed as a PV node. Moreover, the linearized system model of virtual synchronous generator with dynamic droop mechanism is derived and its advantage is discussed. Finally, a modified IEEE 14 bus microgrid system is established in Matlab/Simulink platform. simulation results demonstrate the validity and feasibility of the proposed method. © 2017 IEEE.

关键词： Dynamics

来源：评论

学校读者我要写书评

暂无评论

Deep transfer network with joint distribution adaptation: A new intelligent fault diagnosis framework for industry application

arXiv

引用

arXiv 2018年

作者： Han, Te Liu, Chao Yang, Wenguang Jiang, Dongxiang Department of Energy and Power Engineering Tsinghua University Beijing100084 China State Key Lab of Control and Simulation of Power System and Generation Equipment Tsinghua University Beijing100084 China

In recent years, an increasing popularity of deep learning model for intelligent condition monitoring and diagnosis as well as prognostics used for mechanical systems and structures has been observed. In the previous studies, however, a major assumption accepted by default, is that the training and testing data are taking from same feature distribution. Unfortunately, this assumption is mostly invalid in real application, resulting in a certain lack of applicability for the traditional diagnosis approaches. Inspired by the idea of transfer learning that leverages the knowledge learnt from rich labeled data in source domain to facilitate diagnosing a new but similar target task, a new intelligent fault diagnosis framework, i.e., deep transfer network (DTN), which generalizes deep learning model to domain adaptation scenario, is proposed in this paper. By extending the marginal distribution adaptation (MDA) to joint distribution adaptation (JDA), the proposed framework can exploit the discrimination structures associated with the labeled data in source domain to adapt the conditional distribution of unlabeled target data, and thus guarantee a more accurate distribution matching. Extensive empirical evaluations on three fault datasets validate the applicability and practicability of DTN, while achieving many state-of-the-art transfer results in terms of diverse operating conditions, fault severities and fault types. Copyright © 2018, The Authors. All rights reserved.

关键词： Fault detection

来源：评论

学校读者我要写书评

暂无评论

Design of grounding system for wind-photovoltaic-energy storage Hybrid power station 4

Design of grounding system for wind-photovoltaic-energy stor...

引用

2014 4th International Conference on High Voltage Engineering and Application, ICHVE 2014

作者： Lin, Cheng Sen, Wang Zhizhong, Li Jing, Wang Bo, Zhang Weidong, Shi Power Grid Grounding Engineering Laboratory of State Grid Corporation of China Xi'an Shaanxi710049 China State Key Laboratory of Control and Simulation of Power System and Generation Equipments Department of Electrical Engineering Tsinghua University Beijing100084 China China Electric Power Research Institute Beijing100192 China

ISBN: (纸本)9781479966134

Based on the Chinese demonstration project of Zhangbei wind-photovoltaic-energy storage (W-PV-ES) hybrid generation, which is the world's biggest and Chinese first new energy utilization platform, the design of grounding system for W-PV-ES Hybrid power station was studied in this paper. Firstly according to the soil resistivity of that power station, measured by the Wenner four-electrode method, the soil constitution, that is three-level layer in summer and is four-level layer including an 1.5m high and 2000·m permafrost in winter, was got, and grounding grid models of W-PV-ES hybrid generation was studied. Then grounding system of that W-PV-ES station was designed, that was the single wind turbine uses concentric bicyclic earth electrode, whose radius are 7m and 10m, and the PV-ES power station uses one horizontal earth electrode every 10m in one direction, every 50m in another direction, and there are 2.5m long vertical grounding rods every 10m around the PV-ES station. For the substation, we adopt the horizontal grounding grid with a 10m interval between conductors and 0.8m burial depth. On the condition that earth current is 10KA, the earth's surface potential, contact potential, and step potential were simulated. After that safety of 35kV system and secondary system were analyzed, when there was short trouble. Finally influence on earth resistance by different grounding materials was studied, galvanized flat steel and copper material was presented as two kinds of selection schemes of grounding materials for considering economic considerations. © 2014 IEEE.

关键词： Energy storage

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：