检索结果-内蒙古大学图书馆

Inherent Robustness Properties of Quasi-infinite Horizon MPC

IFAC Proceedings Volumes 2011年第1期44卷 179-184页

作者： Shuyou Yu Marcus Reble Hong Chen Frank Allgöwer Institute of Systems Theory and Automatic Control University of Stuttgart Germany State key laboratory of automobile dynamic simulation Department of Control Science and Engineering Jilin University PR China

Abstract We consider inherent robustness properties of model predictive control (MPC) for continuous-time nonlinear systems with input constraints and terminal constraints. We show that when the linear quadratic control law is chosen as the terminal control law, and the related Lyapunov matrix is chosen as the terminal penalty matrix, MPC with nominal prediction model and bounded disturbances has some degree of inherent robustness. We emphasize that the input constraint sets can be any compact set rather than convex sets, and our results do not rely on the continuity of the optimal cost functional or control law in the interior of the feasible region.

关键词： Nonlinear MPC inherent robustness input constraints terminal constraints

来源：评论

学校读者我要写书评

暂无评论

Study on the loss reduction of high-efficient high-voltage series induction motors

Study on the loss reduction of high-efficient high-voltage s...

引用

2011 International Conference on Electrical Machines and systems, ICEMS 2011

作者： Lingyun, Bai Zhengming, Zhao Yi, Lei Shuping, Wang State Key Laboratory of Control and Simulation of Power System and Generation Equipment Department of Electrical Engineering Tsinghua University Beijing 100084 China Beijing Command College of CAPF Beijing 100012 China Anhui Electrical Research Institute Hefei 230022 China

ISBN: (纸本)9781457710445

On the basis of analyzing the composition of losses in high-efficient high-voltage asynchronous motors, the approaches of increasing the efficiency of the motors is investigated in this paper. The approaches concern with the improvement of material, winding, fan, magnetic groove and so on. By taking the economy and efficiency into account synthetically, the design of the YKK series induction motors is carried on, and it is realized by software simulation. © 2011 IEEE.

关键词： Induction motors

来源：评论

学校读者我要写书评

暂无评论

Traveling waves based faulted feeder selector and its field application

Traveling waves based faulted feeder selector and its field ...

引用

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

作者： Shi, Shenxing Wang, Jun Li, Aiming Du, Xinchun Cao, Xiaoxia Du, Yajun Dong, Xinzhou State Key Lab. of Control and Simulation of Power Systems and Generation Equipments Dept. of Electrical Engineering Tsinghua University Haidian District Beijing 100084 China Yulin Power Company Shaanxi 719000 China China Jiuquan Satellite Launch Center Plumbing Electrical Station Jiuquan 732750 China

ISBN: (纸本)9781424496198

The paper proposes faulted feeder selector in power distribution system with neutral non-effectively grounded. At first, the paper presents basic principle of single-phase-to-ground fault feeder selection based on traveling waves, which compares amplitude and polarity of the initial current traveling waves in all feeders. Then the implementation scheme, including hardware design and software flowchart is presented. At last field application of faulted feeder selector is introduced. The field operation results validated the correctness of faulted feeder selector based on transient traveling wave. © 2011 IEEE.

关键词： Electric grounding

来源：评论

学校读者我要写书评

暂无评论

Research on pilot protection applied in aircraft annular power distribution system

Research on pilot protection applied in aircraft annular pow...

引用

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

作者： Jiang, Zhongshan Liu, Yanping Wang, Bin Dong, Xinzhou Wang, Yan Naval Aeronautical and Astronautical University Yantai 264001 China State Key Lab. of Control and Simulation of Power Systems and Generation Equipments Dept. of Electrical Engineering Tsinghua University Haidian Beijing 100084 China Beijing Wuzi University Beijing 101149 China

ISBN: (纸本)9781424496198

In the annular power distribution system, short-circuit fault of bus-bars will do fatal harm to aircraft, and it is necessary to protect the ring-net bus-bars. Protecting bus-bars has to meet the requirements that protection devices do not refuse to operate and backup protection devices do not act incorrectly. This paper builds a model about the annular power distribution system and stimulates the fault system based on MATLAB. According to the fault features, directional blocking pilot protection is put forward. The results prove that the new method can achieve automatic isolation of the bus-bar at fault, ensures the safety of aircraft power distribution system, and it is of great importance to improve the reliability of aircraft power distributing. © 2011 IEEE.

关键词： MATLAB

来源：评论

学校读者我要写书评

暂无评论

Study on Over-Voltage of 220 kV Transformer＇s Neutrals and Protection Strategy

引用

Journal of Energy and power Engineering 2011年第11期5卷 1102-1108页

作者： H.P. Yu S.M. Chen P.C. Yang H. Yin G.L. Wu State Key Lab of Control and Simulation of Power Systems and Generation Equipments Department of Electrical Engineering Tsinghua University Beoing 100084 China Chongqing Electric Power Research Institute Chongqing 401123 China

In order to limit short-circuit current and satisfy the need of relay setting, only part of the 220 kV power transformer is grounded, so on the neutrals of ungrounded transformers will appear the over-voltage. Currently the value of over-voltage on transformer neutral point and the corresponding protection strategy is based on theoretical formula. This article uses the PSCAD/EMTDC software to calculate the over-voltage on the neutral point of 4 ungrounded power transformers in Chongqing 220 kV power grid. The result shows that the power frequency transient over-voltage on the neutrals may reach 178 kV. If the single-phase grounding fault occurs in ungrounded power system, the power frequency over-voltage on the neutrals will be more serious and rise to 138.6 kV. Non-full phase operation may cause serious ferro-resonance over-voltage on the neutrals of no-load transformer, which may last for seconds and may rise to 723.7 kV, causing serious threat to the transformer neutrals and line-side equipment. The article also studies the gap parameter which should be taken on the neutrals of 220 kV transformers at the end.

关键词： Neutral point power transformer arrester gap power frequency over-voltage lightning over-voltage.

来源：评论

学校读者我要写书评

暂无评论

A predictive DC voltage control scheme for back-to-back converters based on energy balance modeling

A predictive DC voltage control scheme for back-to-back conv...

引用

International Conference on Electrical Machines and systems (ICEMS)

作者： Lu Yin Zhengming Zhao Ting Lu Fanbo He Liqiang Yuan State Key Laboratory of Control and Simulation of Power System and Generation Equipment Department of Electrical Engineering Tsinghua University Beijing China

This paper presents a predictive control scheme of DC-link voltage for back-to-back converters based on energy balance modeling. Since the variation of DC-link voltage is affected by the energy mismatch between rectifier and inverter, the energy distribution in a rectifier-inverter is analyzed. Moreover, in order to calculate the input and output energy in one control period accurately, the grid current is regulated by predictive control and the instantaneous active power consumed by the induction motor is estimated. Then, an equation based on energy balance in one control period is established, and the DC-link voltage can be controlled by solving it. Finally, simulation results show that with the proposed control scheme, the back-to-back converter exhibits both good dynamic and steady-state performances.

关键词： Voltage control Induction motors Rectifiers Capacitors Vectors Pulse width modulation Inverters

来源：评论

学校读者我要写书评

暂无评论

Optimal design of the back-to-back IGBT-based converter with the concept of systematic safe operating area

Optimal design of the back-to-back IGBT-based converter with...

引用

International Conference on Electrical Machines and systems (ICEMS)

作者： Gaoyu Zou Zhengming Zhao Liqiang Yuan Xuesong Wang Ting Lu State Key Laboratory of Control and Simulation of Power System and Generation Equipment Department of Electrical Engineering Tsinghua University Beijing China

The key parameters of SOA (safe operating area) of semiconductor devices are hard to be measured when converter is operating, which is not helpful to protect converter at any time. On the other hand, surplus estimating method is widely used to design the main circuit. In order to guarantee the whole system works safely and improve utilization rate of devices, the concept of SSOA (systematic safe operating area) is presented. By determining the relationship of key parameters between devices and converter, the expression of SSOA is described quantitatively. Then it is implemented as a basic rule to design a back-to-back converter based on IGBT for 55kW induction motor optimally. Rated value of DC-link voltage and grid filter of the system is obtained reasonably as well.

关键词： Inductance Insulated gate bipolar transistors Rectifiers power harmonic filters Semiconductor optical amplifiers Induction motors

来源：评论

学校读者我要写书评

暂无评论

How to guide a sustainable industrial economy: Emergy account for resources input of Chinese industry

引用

Procedia Environmental Sciences 2011年 5卷 51-59页

作者： B. Zhang G.Q. Chen Q. Yang Z.M. Chen B. Chen Z. Li State Key Laboratory of Turbulence and Complex Systems College of Engineering Peking University Beijing 100871 China State Key Joint Laboratory of Environmental Simulation and Pollution Control School of Environment Beijing Normal University Beijing 100875 China

Emergy analysis provides a feasible approach to evaluate the status and position of different energy carriers in the universal energy hierarchy. In this paper, an emergy-based method is conducted to measure the resources input of Chinese industry from 1997 to 2006. Resources inflows including fossil fuels, mineral resources, agricultural products, and other imported materials are accounted, based on which related indicators including resources intensity, industrial output, and environmental emissions are investigated. Results show a steady upward trend for the total resources input of Chinese industry during the past decade. The total resources input amounted to 1.53×1025 sej in 2006, of which non-renewable one accounted for 70.65% owing to the dominating input of fossil fuels and nonmetal minerals. Resources intensity measured by the ratio of resources input to industrial value added declined gradually during 1997–2002, but the rapid expansion of resource–intensive sub–sectors resulted in a reverse trend since 2003. The current resources use pattern of Chinese industry is characterized by increasing input of non-renewable resources, excessive expansion of resource–intensive production, and tremendous challenge from environmental pressure.

关键词： Emergy Resources input Chinese industry

来源：评论

学校读者我要写书评

暂无评论

A parallel based real-time electromagnetic transient simulator for IPS

A parallel based real-time electromagnetic transient simulat...

引用

IEEE Electric Ship Technologies Symposium, ESTS

作者： Yuan Gong Laijun Chen Ying Chen Yin Xu State Key Laboratory of Control and Simulation of Power System and Generation Equipments Department of Electrical Engineering Tsinghua University Beijing China

IPS has many special characteristics, such as using multi-phase, multi-frequency and hybrid AC/DC devices. As a result, existing electromagnetic transient simulators developed for power systems on land do not apply to IPS. This paper aims to build up a parallel based real-time electromagnetic transient simulator for IPS. A fast multi-switching process method for parallel electromagnetic transient simulations is coined to handle the tremendous switch events in IPS. To solve the difficulties brought by multi-phase machines in IPS, a multilevel hybrid parallel algorithm is forged through the combination of component level and network level parallelization. Based on the key techniques mentioned above, a parallel simulator is built up. Through sufficient testing to typical examples of IPS, the accuracy and high-efficiency of the simulator are proved.

关键词： Computational modeling Switches Generators Real time systems Parallel algorithms Circuit faults Testing

来源：评论

学校读者我要写书评

暂无评论

Design, simulation and analysis of the low stray inductance bus bar for voltage source inverters

Design, simulation and analysis of the low stray inductance ...

引用

International Conference on Electrical Machines and systems (ICEMS)

作者： Liqiang Yuan Hualong Yu Xuesong Wang Zhengming Zhao State Key Laboratory of Control and Simulation of Power System and Generation Equipment Department of Electrical Engineering Tsinghua University Beijing China

Hard-switching technique under the high voltage and high current is one of main trends of high power inverters. Under this switching mode, the stray parameters of the commutating loops, especially the stray inductance of the DC bus bar, have significant influence on the switching process, electromagnetic interference and component stress of the semiconductor switches. It becomes one of the key points for the safe operation of inverters. Based on an actual 55 kW inverter, the design, simulation and analysis for its bus bar is described in this paper. The bus bar model is built with the method of Partial Element Equivalent Circuit (PEEC), and the stray parameters are extracted from PEEC model and applied in the circuit simulation. Compared with the experimental results, the modeling validity is proved, and the simplified modeling process and design principles for complex physical bus bar are presented.

关键词： Integrated circuit modeling Equivalent circuits Inductance Inverters Capacitance Conductors Analytical models

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：