检索结果-内蒙古大学图书馆

SSRN 2022年

作者： Liu, Shuming Liu, Shuqi Wang, Qian Zuo, Zhou Liang, Xidong Chen, Zhong State Key Laboratory of Control and Simulation of Power System and Generation Equipment Department of Electrical Engineering Tsinghua University Beijing100084 China School of Material Science and Engineering Nanyang Technological University 639798 Singapore

Insulator is an important component of outdoor insulation systems. It works in complex environments and faces a series of problems such as surface contamination, loss of hydrophobicity, accumulation of surface charges, which may eventually lead to flashover. Aiming to solve these problems in a simple and scalable method, we propose a multifunctional nano-coating based on SiO 2 /PDMS/EP. By the combination of multiscale structure and low surface energy modification, this coating shows excellent water-repellency performance, a large contact angle greater than 160° and a small rolling angle near 0° are achieved on coated silicone rubber, which enables the surface with excellent self-cleaning performance. Benefiting from the multiscale roughness, the heat transfer is inhibited by the reduced contact area, which further slows down the icing process on coated silicone rubber. The de-icing force on coated silicone rubber is also smaller than that on pristine silicone rubber. This coating also introduces many shallow traps to the surface, which is beneficial to the fast surface charge dissipation in a short time. Besides, the high water-repelling ability can promote the droplet to roll away under the action of electrical field force, which alleviates the electrical distortion caused by the droplets. As a result, the wet flashover voltage of coated silicone rubber is 60% higher than that of pristine silicone rubber. This multifunctional coating is a facile, scalable, and effective approach to improving the comprehensive surface performance of insulators. © 2022, The Authors. All rights reserved.

关键词： Flashover

来源：评论

学校读者我要写书评

暂无评论

A dynamic multi-level temporal and spatial coordination method for orderly power utilization based on customer load curtailment cost characteristics

引用

Dianwang Jishu/power system Technology 2016年第2期40卷 425-432页

作者： Yan, Qingguo Tong, Xing Zhang, Ning Chen, Xiao Yi, Yongxian State Grid Jiangsu Electric Power Company NanjingJiangsu Province210024 China State Key Lab of Control and Simulation of Power Systems and Generation Equipments Dept. of Electrical Engineering Tsinghua University Haidian District Beijing100084 China Jiangsu Electric Power Company Research Institute NanjingJiangsu Province210019 China State Grid Key Laboratory of Electric Power Metrology NanjingJiangsu Province211103 China

When there is power supply shortage or emergency event in power system, orderly power utilization needs to be applied to cut down electricity demand to maintain power supply for important electricity consumers. Current orderly power utilization fails to consider curtailment costs for different regions and customers, and ignores temporal continuity and production regularity of customer, leading to inefficient load curtailment scheduling. This paper proposes a dynamic multi-level temporal and spatial coordinated shortage allocation method considering customer load curtailment costs for orderly power utilization. Load curtailment cost function is established from individual customer level up to provincial electrical grid level. An optimization model is proposed to strategically rearrange customer load profiles across multiple periods. Case studies show that the method efficiently coordinates power shortage in temporal and spatial scale, and significantly brings down economic cost due to curtailment allocation. This model could help promote customer satisfaction level in orderly power utilization. © 2016, power system Technology Press. All right reserved.

关键词： Electric power utilization

来源：评论

学校读者我要写书评

暂无评论

Performance of negative sequence pilot protection applications in transmission line with open-phase operation

Performance of negative sequence pilot protection applicatio...

引用

IEEE/PES Transmission and Distribution Conference and Exhibition: Asia and Pacific

作者： Bin Wang Xinzhou Dong Zhiqian Bo Andrew Klimek State Key Lab of Control and Simulation of Power Systems and Generation Equipments Department of Electrical Engineering Tsinghua University Beijing China AREVA T and D UK Limited Stafford UK

ISBN: (纸本)9781424452293

The performance of the negative sequence pilot protection (NSPP) is less deteriorated by the phase-ground shunt capacitance since the negative sequence current loops in phase-phase lines. Hence NSPP is a good candidate for the main protection in UHV lines with the special characteristic of larger charging current. But as we all known, NSPP is not suit to the open-phase operations in transmission line, which limited its wide applications in HV/EHV lines in history. In response to this question, the performance of NSPP in transmission line with open-phase operation is analyzed, and the mal-operation reason of the NSPP relay is discovered. Then an improved algorithm for faults detection is proposed in open-phase line, and the simulation results verified its validity. The work in this paper is only the basic steps, the more research, such as the sensitivity and transient characteristics of ground fault detections in open-phase line should be discussed further.

关键词： Protection Transmission lines Capacitance Fault detection Voltage control power system simulation power system transients History Performance analysis Relays

来源：评论

学校读者我要写书评

暂无评论

Communication test and analysis of integrated protection system in digital substation

Communication test and analysis of integrated protection sys...

引用

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

作者： Wu, TingTing Shi, ShenXing Wang, Bin Zhou, YunHai Dong, XinZhou Liu, Kun Yang, YueLin School of Electrical Engineering and Renewable Energy China Three Gorges University Yichang 443000 China State Key Lab. of Control and Simulation of Power Systems and Generation Equipments Dept. of Electrical Engineering Tsinghua University Haidian District Beijing 100084 China College of Information and Electrical Engineering CHINA Agricultural University Haidian District Beijing 100083 China

ISBN: (纸本)9781424496198

The development of digital substation provides new opportunity for integrated protection. However, the realization of integrated protection is constrained by serial communication between process level and bay level. Based on developed digital integrated protection and control system platform, the result of a physical simulation test concerning communication system reveals the problem of communication instability and packet loss. In this paper, the impact of GPS exerted on stability of integrated protection is tested and analyzed. Without GPS time setting of Merging Unit(MU) in different bay, the integrated protection system will lose data in one minute after running. With GPS, the communication is stable and reliable, but the time interval between two packets in a cycle is quite long. Since sampling of MU in different bay is synchronized by GPS, the availability of integrated protection system is directly affected by communication of integrated protection in digital substation. © 2011 IEEE.

关键词： Packet loss

来源：评论

学校读者我要写书评

暂无评论

ANALYSIS OF FATIGUE LIFE LOSS OF DRIVETRAIN OF DOUBLY-FED WIND TURBINES UNDER SHORT-CIRCUIT FAULT OF power GRID

ANALYSIS OF FATIGUE LIFE LOSS OF DRIVETRAIN OF DOUBLY-FED WI...

引用

International Conference on Renewable power generation

作者： Qiu Shilong Li Hui Gong Lijiao Wang Bin Chai Zhaoseng Wu You Department of Mechanical and Electrical Engineering Shihezi University Shihezi China State Key Laboratory of Power Drivetrain Equipment and System Security Chongqing University Chongqing China State Key Lab of Control and Simulation of Power Systems and Generation Equipments (Department of Electrical Engineering) Tsinghua University Haidian District Beijing China State Key Laboratory of Power Drivetrain Equipment and System Security Chongqing University Chongqing China

ISBN: (数字)9781839531248

ISBN: (纸本)9781839531255

The shafting drivetrain of the doubly fed wind turbine is the part with the highest failure rate. The electromagnetic torque fluctuation caused by the grid fault easily results in the torsional vibration fatigue loss of the shaft. Accordingly, the influences of drivetrain fatigue life loss under different grid faults require investigation. Firstly, the four-mass model of the drivetrain is constructed on the basis of MATlab/Simulink. Secondly, the electromagnetic torque response under short-circuit fault of the grid is obtained via model simulation. Finally, the effects of different types of grid faults on the fatigue life of the drivetrain are analysed through Mlife. Results show that the electromagnetic torque fluctuation load generated by grid fault has no apparent influence on the fatigue life of the drivetrain in the short term, but the cumulative effect of short-term damage will aggravate the fatigue life loss of the drivetrain and increase the failure risk of the component. The electromagnetic torque generated by the three-phase symmetrical short-circuit is the most violent and has the maximum effect on the fatigue life of the drivetrain.

关键词： WIND TURBINE SHORT-CIRCUIT FAULT TORSIONAL VIBRATION FATIGUE LIFE DRIVETRAIN

来源：评论

学校读者我要写书评

暂无评论

Study of the Vibration Characteristics of 550 kV GIS Circuit Breaker Based on Rigid-Flexible Coupling Model*

Study of the Vibration Characteristics of 550 kV GIS Circuit...

引用

IEEE/ASME (AIM) International Conference on Advanced Intelligent Mechatronics

作者： Yanpeng Ge Bo Liu Shaoshuai Su Yiheng Xu Qiang Sun Weikai Zhang Wensheng Gao Department of Electrical Engineering State Key Laboratory of Control and Simulation of Power System and Generation Equipment Tsinghua University Beijing China Shandong Taikai High Voltage Switchgear Co. Ltd Tai’an China

ISBN: (数字)9798350355369

ISBN: (纸本)9798350355376

High voltage circuit breakers (HVCBs) in the gas insulated switch gear (GIS) play an important role in the control and protection of power system. The mechanical faults account for the largest part of common faults in HVCBs. This paper establishes the rigid-flexible model of a 550 kV GIS HVCB, and experimentally studies the behavior characteristics of the HVCB under mechanical fault situation. Firstly, the fine 3D structure model of the 550 kV GIS HVCB is built and the arc-extinguishing principle of the HVCB is analyzed. Then, the rigid model and the rigid-flexible coupling model of the HVCB’s components and the whole system are established. The vibration signals of the two models are simulated and compared based on the finite element method. The component model mainly consists of the static arc contact and the dynamic arc contact. Furthermore, the mechanical fault is artificially set in the HVCB, and the vibration waveform are obtained. Finally, the simulation data is compared with the experimental results and the fault characteristics are analyzed. This research realizes the modeling, simulation and measurement of HVCB dynamic characteristics, which is of great significance to the diagnosis and prevention of HVCB mechanical faults.

关键词： Vibrations Couplings Solid modeling Three-dimensional displays Circuit breakers power system dynamics High-voltage techniques

来源：评论

学校读者我要写书评

暂无评论

The Influence of Positive Temperature Coefficient Material on the DC Electric Field within Epoxy Composites

The Influence of Positive Temperature Coefficient Material o...

引用

Conference on Electrical Insulation and Dielectric Phenomena, (CEIDP)

作者： Chenyuan Teng Yuanxiang Zhou Ling Zhang Yunxiao Zhang Xuewei Wang Zixia Cheng Meng Huang China State Key Laboratory of Control and Simulation of Power Systems and Generation Equipment Tsinghua University Beijing China The Wind Solar Storage Division of State Key Laboratory of Power System and Generation Equipment School of Electrical Engineering Xinjiang University Urumqi China School of Electrical Engineering Zhengzhou University Zhengzhou China The State Key Laboratory of Alternate Electrical Power System with Renewable Energy Sources North China Electric Power University Beijing China

ISBN: (纸本)9781728195728;9781728195735

Negative temperature (NT) coefficient electrical resistivity of insulating materials causes the distortion of DC electric field, increasing the design and manufacture difficulty of HVDC equipment. The ceramic with positive temperature coefficient (PTC) electrical resistivity was doped into epoxy resin to weaken its temperature dependence of electrical resistivity (0~35 wt%). The electric field and temperature distribution under temperature gradient were simulated. The PTC effect of fillers is able to mitigate the distortion of electric field under temperature gradient, which is through the synergistic optimization of both electrical resistivity-temperature characteristic and thermal conductivity. The optimization of electric field distribution within insulation via BT60/epoxy composites has potential to be used in HVDC electrical equipment.

关键词： Temperature sensors Temperature distribution Temperature dependence Thermal resistance HVDC transmission Conductivity Thermal conductivity

来源：评论

学校读者我要写书评

暂无评论

A fast transient simulation model of DFIG based on the piecewise averaging method

A fast transient simulation model of DFIG based on the piece...

引用

2nd IET Renewable power generation Conference (RPG 2013)

作者： G. Feng Y. Xu Y. Chen H. Gao L. Chen Tsinghua University Beijing Beijing CN State Key Lab of Control and Simulation of Power Systems and Generation Equipments Dept. of Electrical Engineering Tsinghua University Beijing 100084 China

ISBN: (纸本)9781629936017

Due to the power electronic devices in doubly fed induction generators (DFIG), it is very time consuming to simulate the electromagnetic transients of DFIG using its detailed model. Thus it is necessary to have appropriately simplified model of DFIG that maintains desirable accuracy. In this paper, the piecewise averaged model of PWM converters is introduced and applied to the modelling of DFIG. The proposed model divides the simulation time interval into switching periods and recalculates the averaged state equations of PWM converters in each switching cycle. In addition, a predictorcorrector based EMTP algorithm is designed to iteratively solve the model. Instead of treating switching events at the time points when they happen, the new algorithm solves all the switching instants in a switching cycle at the same time, which avoids frequency modification of the system conductance matrix and speeds up EMT simulations of DFIG. simulation results of a single-machine infinity bus system with a DFIG show that the proposed model and algorithm can achieve satisfactory accuracy and efficiency.

关键词： Average modelling Doubly fed induction generators Electromagnetic transient simulation

来源：评论

学校读者我要写书评

暂无评论

Ancillary service for frequency regulation based on multi-energy virtual power plant aggregating factory load

Ancillary service for frequency regulation based on multi-en...

引用

The 11th IET International Conference on Advances in power system control, Operation and Management (APSCOM 2018)

作者： Jiazhen Wang Xinwei Shen Yinliang Xu Qinglai Guo Hongbin Sun Yanbo Chen Shenzhen Environmental Science and New Energy Technology Engineering Laboratory Tsinghua-Berkeley Shenzhen Insitute Tsinghua University Shenzhen China State Key Lab of Control and Simulation of Power System and Generation Equipments Department of Electrical Engineering Tsinghua University Beijing China State Key Laboratory of Alternate Electrical Power System with Renewable Energy Sources North China Electric Power University

ISBN: (数字)9781839530043

With the increasing proportion of renewable energy generation into the power grid, more challenges are coming to the safe and stable operation of the power system. In order to keep the balance in energy market, system operator has to purchase much service in ancillary service market to guarantee the stable operation of the power transmission. Virtual power plant (VPP) has been extensively studied as a concept that aggregates multiple resource forms to serve the electricity market. Meanwhile, with the development of Energy Internet (EI) Error! Reference source not found., more attention has been focused on the optimization and operation of Integrated Energy system (IES), therefore, the introduction and exploration of Multi-energy Virtual power Plant (MVPP) provide possibilities for IES to participate in the Electricity Market and Ancillary Services Market. This paper extracts the flexible electric and heat load in the industrial production process, combining the CHP units and Electric Boiler (EB), which are main heat energy supply devices as well as Energy Storage system (ESS) as a MVPP to provide Frequency Regulation (FR) service to the Auxiliary Service Market. Model Predictive control (MPC) method is applied to control the industrial load, the operation of CHP, EB and ESS are gonging to follow the AGC signal issued by the FR market effectively while avoiding impacts on the production process of the factory. Finally, case study validates the effectiveness of the model.

关键词：

来源：评论

学校读者我要写书评

暂无评论

Overvoltage Suppression Strategy Based on Active control of Current for Half-Wave Commutated Modular Multilevel Converters

Overvoltage Suppression Strategy Based on Active Control of ...

引用

IEEE International Conference on power and Energy systems (ICPES)

作者： Bao Liu Yunfei Xu Guoliang Zhao Nan Fu Chen Jia State Key Laboratory of Advanced Power Transmission Technology China Electric Power Research Institute Beijing China State Key Laboratory of Control and Simulation of Power System and Generation Equipment Tsinghua University Beijing China Electric Power Research Institute of State Grid Liaoning Electric Power Co. Ltd. Shenyang China

ISBN: (数字)9798350391329

ISBN: (纸本)9798350391336

Flexible low-frequency AC transmission technology combines the advantages of 50 Hz AC transmission and DC transmission, and has good application scenarios. High voltage and large capacity AC/AC converters are the core equipment of flexible low-frequency AC transmission systems. The proposal of half-wave commutated modular multilevel converters effectively reduces the number of components and improves system economy. In view of this, this paper proposes an overvoltage suppression strategy for active control of inductor current, which effectively reduces the overvoltage level during commutation. The article first introduces the sparse topology and mathematical model of the half-wave commutated modular multilevel converters. Secondly, the mechanism of overvoltage generation is analyzed. Then, overvoltage suppression strategies are proposed. Finally, a PSCAD simulation model is built to verify the effectiveness and feasibility of the proposed method through simulation.

关键词： Multilevel converters Reactive power Bridge circuits Valves Mathematical models Topology Safety Voltage control Inductors PSCAD

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：