检索结果-内蒙古大学图书馆

作者： Wang, Bin Yang, Lin Dong, Xinzhou Department of Electrical Engineering State Key Lab of Control and Simulation of Power Systems and Generation Equipments Tsinghua University Beijing10084 China

The reflection coefficient of the travelling wave is different with different frequencies because of the inductance and capacitive elements on the boundary of the DC transmission line, which leads to the oscillation of the travelling wave. It is difficult to obtain the wave head's arrival time accurately using travelling wave method to locate fault because of the oscillation. The current travelling wave is the superposition of the incident current travelling wave and the reflected current travelling wave. There is no oscillation in the incident wave. Therefore, a method using incident current wave for fault location is proposed here. The initial current travelling wave and the transmission line boundary function are used to calculate the incident current travelling wave, and the incident wave is used to locate fault. The Prony decomposition algorithm is used to identify boundary function using the initial current travelling wave generated in specific fault condition. PSCAD simulation shows that the influence of oscillations of travelling wave can be eliminated by using incident current wave to locate faults, and the accuracy of fault location is improved. © Institution of Engineering and Technology. All rights reserved.

关键词： Electric lines

来源：评论

学校读者我要写书评

暂无评论

A VCG Payment Scheme for Energy Storages in the Spot Market Considering Levelized-Cost-of-Storage 8

A VCG Payment Scheme for Energy Storages in the Spot Market ...

引用

8th Asia Conference on power and Electrical Engineering, ACPEE 2023

作者： Liu, Jianing Zhao, Yue Su, Zhuo Wang, Ke He, Yujun Guangdong Province Power Grid Co. Ltd Power Dispatching and Control Center Guangzhou China Tsinghua Univeristy State Key Lab of Control and Simulation of Power Systems and Generation Equipments Beijing China

ISBN: (纸本)9798350345520

Energy storages are considered as a key solution in the novel energy system with high penetration of renewables. However, the current power markets are not designed for the participation of energy storage as it has a variable cost. This paper investigates an efficient mechanism in which the energy storage submits his levelized cost of storage, then the storage receives a Vickrey-Clark-Grove payment equal to the increase in social welfare attributable to his presence. This mechanism can encourage the storage to truthfully submit the true operating cost and thus help to optimize the system operation. Moreover, the increments of the storage's own interests and the social welfare are coincidental, so it is incentive compatible. Numerical tests show the advantages of the proposed mechanism over the marginal pricing mechanism. © 2023 IEEE.

关键词： Energy storage

来源：评论

学校读者我要写书评

暂无评论

Repeated Strike Process During Disconnector Operation in Ultra-High Voltage Gas-Insulated Switchgear

引用

Plasma Science and Technology 2016年第3期18卷 247-253页

作者：关永刚蔡元纪陈维江刘卫东李志兵岳功昌张俊民 State Key Lab of Control and Simulation of Power System and Generation Equipments Department of Electrical EngineeringTsinghua UniversityBeijing 100084China State Grid Corporation of China Beijing 100031China China Electric Power Research Institute Beijing 100192China School of Automation Science and Electrical Engineering Beihang UniversityBeijing 100191China

Very fast transient over-voltage （VFTO）, induced by disconnector operations in gas- insulated switchgears, has become the limiting dielectric stress at ultra-high voltage levels. Much work has been done to investigate single-strike waveforms of VFTO. However, little study has been carried out investigating the repeated strike process, which would influence VFTO significantly. In this paper, we carried out 450 effective experiments in an ultra-high voltage test circuit, and conducted calculations through the Monte Carlo simulation method, to investigate the repeated strike process. Firstly, the mechanism of the repeated strike process is proposed, based on the ex- perimentai results. Afterwards, statistical breakdown characteristics of disconnectors are obtained and analyzed. Finally, simulations of the repeated strike process are conducted, which indicate that the dielectric strength recovery speed and polarity effect factor have a joint effect on VFTO. This study enhances the understanding of the nature of VFTO, and may help to optimize the disconnector designed to minimize VFTO.

关键词： disconnector (DS) repeated strike process discharge statistical breakdowncharacteristics ultra-high voltage (UHV) very fast transient over-voltage (VFTO)

来源：评论

学校读者我要写书评

暂无评论

Numerical Analysis of Space Charge Characteristics in Low-density Polyethylene Nanocomposite Under External DC Electric Field

引用

高电压技术 2013年第8期39卷 1813-1820页

作者： ZHOU Yuanxiang ZHANG Ling SHA Yanchao TIAN Jihuan State Key Laboratory of Control and Simulation of Power System and Generation Equipments Tsinghua University Beijing 100084 China ABB Corporate Research Center Beijing 100015 China

The dynamic characteristics of space charge in nanocomposite of low-density polyethylene (LDPE) mixed with inorganic nano- fillers. Different from previous qualitatively theoretical works, we investigated the influence of trap depth, trap volume charge density and injection barrier height on the space charge and the electric field distribution in the nanocomposite under a DC external electric field (100 MV/m) systematically and quantificationally, through numerical simulations based on a bipolar charge transport model. The simulation re- sults showed that, the increase of trap depth would severely distort the balanced electric field distribution with the highest and the lowest electric field of 119 MV/m and 47 MV/m, respectively. It is concluded that the introduction of nanofillers creates more deep traps, which would block space charges by capturing most of them in the vicinity of electrode and hence reduce the local electric field largely. Further theoretical analysis of the simulation indicates that both the high permittivity and the low local electric field of the nanocomposite contri- buted to the increase of injection barrier height, and almost no charge could overcome an injection barrier higher than 1.25 eV. At last, a mechanism of space charge suppression in the LDPE nanocomposite was presented.

关键词：纳米复合材料低密度聚乙烯直流电场空间电荷电荷特性数值分析无机纳米填料陷阱深度

来源：评论

学校读者我要写书评

暂无评论

Rule Extraction in Transient Stability Study Using Linear Decision Trees

引用

中国电机工程学报 2011年第34期31卷 I0006-I0006页

作者： SUN Hongbin WANG Kang ZHANG Boming ZHAO Feng State Key Lab of Control and Simulation of Power Systems and Generation Equipments （Dept. of Electrical Engineering Tsinghua University） Haidian District Beijing 100084 China

Traditional operation rules depend on human experience, which are relatively fixed and difficult to fulfill the new demand of the modern power grid. In order to formulate suitable and quickly refreshed operation rules, a method of linear decision tree based on support samples is proposed for rule extraction in this paper. The operation rules extracted by this method have advantages of refinement and intelligence, which helps the dispatching center meet the requirement of smart grid construction.

关键词：英文摘要内容介绍编辑工作期刊

来源：评论

学校读者我要写书评

暂无评论

Fault classification rules extraction of wind turbine based on C4.5 algorithm

Fault classification rules extraction of wind turbine based ...

引用

Prognostics and Health Management Solutions Conference - PHM: Driving Efficient Operations and Maintenance, MFPT 2012

作者： Chen, Jie Jiang, Dongxiang Yang, Wenguang Deng, Xiaowen Feng, Yongxin State Key Laboratory of Control and Simulation of Power System and Generation Equipments Department of Thermal Engineering Tsinghua University Beijing 100084 China Electric Power Institute Guangdong Grid Company Guangzhou 510080 China

Distinguishing fault types in early time can prevent wind turbines from breaking down. C4.5 algorithm, different from ID3 algorithm, which can deal with continuous parameters, should be a choice fault diagnosis method of wind turbine. This paper strives to extract fault classification rules of wind turbine based on data collected from a small wind turbine in lab.ratory using C4.5 decision tree and validate the rules extracted using another set of data. According to the solution, fault types such as mass imbalance of rotor, aero-dynamic asymmetry, yaw misalignment, gearbox and bearing fault and so on can be distinguished by the method presented in this paper.

关键词： Wind turbines

来源：评论

学校读者我要写书评

暂无评论

Capacity Allocation of Hybrid power system with Hot Dry Rock Geothermal Energy,Thermal Storage,and PV Based on Game Approaches

引用

Journal of Modern power systems and Clean Energy 2023年第1期11卷 290-301页

作者： Yang Si Laijun Chen Xuelin Zhang Xiaotao Chen Shengwei Mei Qinghai Key Lab of Efficient Utilization of Clean Energy(Tus-Institute for Renewable Energy) University of QinghaiXining 810016China State Key Laboratory of Control and Simulation of Power System and Power Generation Equipment(Electric Machinery Department Tsinghua University)Beijing 100084China Technical Institute of Physics and Chemistry Beijing 100190China IEEE

This study utilizes hot dry rock(HDR)geothermal energy,which is not affected by climate,to address the capacity allocation of photovoltaic(PV)-storage hybrid power systems(HPSs)in frigid plateau *** study replaces the conventional electrochemical energy storage system with a stable HDR plant assisted by a flexible thermal storage(TS)*** HPS consisting of an HDR plant,a TS plant,and a PV plant is *** approaches are introduced to establish the game pattern model of the proposed HPS as the *** annualized income of each player is used as the payoff ***,non-cooperative game and cooperative game approaches for capacity allocation are proposed according to the interests of each player in the proposed ***,the proposed model and approaches are validated by performing calculations for an HPS in the Gonghe Basin,Qinghai,China as a case *** results show that in the proposed non-cooperative game approach,the players focus only on the individual payoff and neglect the overall system *** proposed cooperative game approach for capacity allocation improves the flexibility of the HPS as well as the payoff of each game ***,the HPS can better satisfy the power fluctuation rate requirements of the grid and increase the equivalent firm capacity(EFC)of PV plants,which in turn indirectly guarantees the reliability of grid operation.

关键词： Capacity allocation equivalent firm capacity game theory hot dry rock hybrid power system

来源：评论

学校读者我要写书评

暂无评论

Breakdown phenomena caused by electrical tree degradation in high density polyethylene under high frequency voltage

引用

Gaodianya Jishu/High Voltage Engineering 2007年第12期33卷 14-18页

作者： Zhou, Yuan-Xiang Xing, Xiao-Liang Nie, Qiong Wang, Yun-Shan Wang, Ning-Hua Liang, Xi-Dong Guan, Zhi-Cheng State Key Lab. of Control and Simulation of Power Systems and Generation Equipments Department of Electrical Engineering Tsinghua University Beijing 100084 China

The shape change of electrical tree propagating in ice-water quenched high-density polyethylene (HDPE) film under AC voltage of different frequency ranging from 50 Hz to 90 kHz as well as the breakdown phenomena caused by the treeing degradation under high frequency condition were studied. The electrical treeing aging experiment is carried out at room temperature. The shape change of electrical tree and the arcing process during the experiment is observed via a digital micro-observing system. It is found that the arcing process can be obviously observed under a high frequency voltage compared with that under low frequency voltage. It is also found that under different frequency voltages the electrical tree initiation shape is different. Most of the electrical trees are branch-shape tree under lower frequency voltage. When the frequency is higher than 5 kHz, trunk-shape tree and bosk-like tree appears. Once the frequency is higher than 50 kHz, breakdown tree can be found out. It is shown that the tree shape conversion is influenced by the frequency. The electrical tree usually has a simple shape and rarely changes under low frequency voltage in one hour or more. However, under a high frequency voltage, the electrical tree shape changes more frequently and has a large probability to breakdown. The influence of frequency on material polarization process, fatigue and thermo effect is considered as the main causes of the experiment results. The more serious destruction caused by high frequency electrical treeing degradation can well explain the reason of insulation premature inactivation in mid-frequency or high-frequency electrical equipment.

关键词：聚乙烯树老化电树形态转换击穿频率

来源：评论

学校读者我要写书评

暂无评论

A Stochastic Resource Management Scheme for Multi-Energy Group control system 3

A Stochastic Resource Management Scheme for Multi-Energy Gro...

引用

3rd IEEE International Conference on power, Electronics and Computer Applications, ICPECA 2023

作者： Ding, Ran Sun, Rongfu Geng, Yan Yao, Yiming Zhao, Ergang Xu, Lina State Grid Jibei Electric Power Company Limited Beijing China Tsinghua University State Key Lab. of Control and Simulation of Power System and Generation Equipment Dept. of Electrical Engineering Beijing China

ISBN: (纸本)9781665472784

The interaction between various energy supply systems (cold, heat, electricity, gas, etc.) is becoming more tightly coupled as social economy and technology advance. Multi-energy systems are ineffective because different types of energy systems run independently. In order to protect the data privacy of each sub-system, this research suggests an ideal resource management framework for a multi-energy group control system. The energy hub (EH) paradigm is first suggested. When deploying EHs, the physical constraints of various energy systems are taken into account. Through scenario-based stochastic programming, the uncertainties of renewable energy are considered. According to the leader-follower relationship between multi-energy group control system operators and energy hub operators (EHOs), Benders decomposition is applied to decentralize the decision-making process. Finally, an example is given to illustrate the effectiveness of the proposed model and algorithm. © 2023 IEEE.

关键词： Data privacy

来源：评论

学校读者我要写书评

暂无评论

Modeling and simulation analysis of dual-rotor vibration system with multiple faults

Modeling and simulation analysis of dual-rotor vibration sys...

引用

Society for Machinery Failure Prevention Technology Conference 2018: Intelligent Technologies for Equipment and Human Performance Monitoring, MFPT 2018

作者： Yang, Yizhou Liu, Chao Jiang, Dongxiang Yang, Wenguang State Key Lab. of Control and Simulation of Power Systems and Generation Equipment Department of Thermal Engineering Tsinghua University Beijing100084 China

Dual-rotor system is an important rotor form in rotating machinery like gas turbine engine. Its complex structure results in rich dynamical behaviors and more probability to failure. The modeling and simulation of the dual-rotor system can help to understand its dynamic characteristics and provide theoretical support for the design, operation and maintenance. In this paper, a dynamic model of a dual-rotor system with multiple rotor faults is established. The dual-rotor vibration model without any fault is built by finite element method, where the two shafts are connected by an inter-shaft bearing and nonlinear models of rolling element bearing and squeeze film damper are considered. The numerical integration method of Newmark-β is used to obtain the steady-state vibration response of the system. Then rotor faults are introduced to the system model, including unbalance, misalignment, looseness and rub-impact. The steady-state responses of single faults in the dual-rotor system are analyzed and typical fault features are obtained. Then coupling characteristics between different rotor faults, and the influences of the squeeze film dampers on the dynamic characteristics and fault features of the system are studied. © 2018 Proceedings of the 9th International Symposium on Imprecise Probability.

关键词： Rotating machinery

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：