检索结果-内蒙古大学图书馆

Sixth International Conference on Power Electronics and Drive systems, PEDS 200

作者： Yuan, Liqiang Zhao, Zhengming Yang, Zhi Dept. of Electrical Engineering Tsinghua Univ. State Key Lab of Control and Simulation of Power System Beijing China Dept. of Frequency-converter and Control System GuoDian NanJing Automation Co. Ltd. Nanjing China

ISBN: (纸本)0780392965

The power-loss models for different switching states of IGCTs and diodes in MV (medium voltage) three-level NPC (neutral point clamped) inverters are presented in this paper. The models, simulation implementation and the revisional experiments on IGCT test platform are described in details. The relation between the power losses and the other elements of the inverter is analyzed and discussed. © 2005 IEEE.

关键词： Electric inverters

来源：评论

学校读者我要写书评

暂无评论

Residual voltage transformation method for short-circuit current calculation with matrix transformation

引用

Zhongguo Dianji Gongcheng Xuebao/Proceedings of the Chinese Society of electrical engineering 2005年第23期25卷 61-65页

作者： Jiang, Tong Bai, Xue-Feng Guo, Zhi-Zhong Lu, Ying Laboratory of Power System Protection and Dynamic Security Monitoring and Control North China Electric Power University Beijing 102206 China School of Electrical Engineering and Automation Harbin Institute of Technology Harbin 150001 China Dept. of Electrical Engineering Tsinghua University Beijing 100084 China

Unbalanced element brings a big problem to fault analysis of symmetrical components method. According with fault analysis of phase components, a residual voltage transformation method for short-circuit current calculation is presented with matrix translation in the place of classical sequence networks connection, which is suitable for both phase coordinates and symmetrical components coordinates. Calculation formulas are proposed with matrices calculation to deal with unsymmetrical faults and parameter matrices for various faults are listed. Analysis of simultaneous faults with unbalanced parameter element is done without calculation qualities increased. Simple examples have shown that the method is practical and suitable for programming.

关键词： Short circuit currents

来源：评论

学校读者我要写书评

暂无评论

Snubberless switching-off characteristics of IGCTs equipped in high power three-level neutral point clamped converters

Snubberless switching-off characteristics of IGCTs equipped ...

引用

International Conference on electrical Machines and systems (ICEMS)

作者： Liqiang Yuan Zhengming Zhao Haitao Zhang Zhi Yang Bing Li Jianzheng Liu Department of Electrical Engineering Tsinghua University Beijing China Department of Frequency-Converter and Control System Guodian Nanjing Automation Company Limited Nanjing China

Along with the improved design and broad applications of multi-level topologies, as a new commercial power switch device in recent years, IGCT has led the rapid development of high power converters in many applications, such as medium voltage adjustable speed drive and FACTs. Since the power electronic device is the base of these converters, the switching-off characteristics of IGCTs have become one of the key points in converters' design and analysis, especially when snubber circuits are absent. This paper focuses on the snubberless switching-off characteristics of IGCTs equipped in the high power three-level neutral point clamped (NPC) converter. According to the physical characteristics of switch devices and commutating mechanism between different switching processes in the converter, the switching-off characteristics of IGCTs in different topology positions under different switching conditions are described, simulated and tested. The results of simulation and experiments are compared, especially the voltage spikes by IGCTs' switching off. The relation between the switching-off characteristics and the other elements of the converter is also discussed in detail, such as topology position, PWM strategy and mechanical structure. Finally, some helpful conclusions for high power converters' design and analysis are drawn

关键词： Switching converters Circuit topology Switches Medium voltage Variable speed drives Power electronics Switching circuits Snubbers Testing Pulse width modulation

来源：评论

学校读者我要写书评

暂无评论

Dynamic system control of Gas Jet Flames Distribution by Predictive control Method

Dynamic System Control of Gas Jet Flames Distribution by Pre...

引用

IEEE International Symposium on Intelligent control (ISIC)

作者： Xubin Sun Hong Wang Institute of Automation Chinese Academy and Sciences Beijing China Control System Centre School of Electrical and Electronics Engineering University of Manchester Institute of Science and Technology Manchester UK

ISBN: (纸本)0780389379

This paper presents a predictive control method to the output probability density function (PDF) control for a dynamic flame system. The system consists of a static temperature model of gas jet flames and a second order actuator which leads the closed loop system to be a second order dynamic one. At first, the temperature distribution of the flame along the cross section is approximated. Then the flame energy distribution (FED) is obtained as the output to be controlled as approximated by a B-spline expansion. A singular state space model is used to describe the dynamic system with the weights of the B-spline functions as the state variables. Finally, a predictive control algorithm is designed for such an output PDF system. A case study has been included in this paper on the closed loop control of the combustion flames distribution systems

关键词： control systems Fires Predictive control Spline Probability density function Actuators Closed loop systems Temperature distribution State-space methods Prediction algorithms

来源：评论

学校读者我要写书评

暂无评论

Optimizing the structure of hierarchical mixture of experts using genetic algorithms

Optimizing the structure of hierarchical mixture of experts ...

引用

2004 2nd International IEEE Conference 'Intelligent systems' - Proceedings

作者： Karras, Dimitrios A. Vlitakis, Constantinos E. Boutalis, Yiannis S. Mertzios, Basil G. Chalkis Institute of Technology Dept. Automation Hellenic Open University Rodou 2 Ano Iliupolis Athens 16342 Greece Democritus University of Thrace Dept. Electrical Engineering 67100 Xanthi Greece Department of Automation Thessaloniki Inst. Technol. Thessaloniki Hellas Democritus University Lab. of Automatic Control System Xanthi Hellas

ISBN: (纸本)0780382781

This study is an effort to give a practical solution in the problem of optimizing the structure of the Hierarchical Mixture of Experts model, which is a natural extension of the Associative Gaussian Mixture of Experts system. We present two novel methods for optimizing such structures using Genetic Algorithms. Special concern is taken for reducing the computational time so as to efficiently allow the structure to "grow" while it evolves with the Genetic Algorithm. The main contribution of the paper lies on the efficient, topologically oriented, representations of such architectures so as to be optimized through involving genetic algorithms.

关键词： Expert systems

来源：评论

学校读者我要写书评

暂无评论

Operation principle and control method of a linear motor made by magnetically controlled shape memory alloy

Operation principle and control method of a linear motor mad...

引用

International Conference on Power system Technology (POWERCON)

作者： Fengxiang Wang Qingxin Zhang Wenjun Li Xinjie Wu School of Electrical Engineering Shenyang University of Technology Shenyang China Department of Automation Control System Shenyang University of Aviation Technology Shenyang China Physics Department Liaoning University Shenyang China

ISBN: (纸本)0780386108

Magnetically controlled shape memory (MSM) materials are a new way to produce motion and force. The material changes shape in a magnetic field. Shape changes are even 10 percent and response time is less than a millisecond. Usual applications of the material are actuators that produce linear motion. In this paper the magnetic controlled properties of MSM material, the operation principle, design and control method of an inchworm type linear MSM motor are introduced. The tested results of a prototype machine are also presented.

关键词： Shape control Shape memory alloys Magnetic materials Force control Motion control Magnetic fields Delay Hydraulic actuators Magnetic properties Design methodology

来源：评论

学校读者我要写书评

暂无评论

Robust tracking performance enhancement through uncertainty division

Robust tracking performance enhancement through uncertainty ...

引用

2003 European control Conference, ECC 2003

作者： Gil-Martínez, M. García-Sanz, M. System Engineering and Automation Group Electrical Engineering Department University of La Rioja Luis de Ulloa 20 Logroño26004 Spain Automatic Control and Computer Science Department Public University of Navarra Campus Arrosadía s/n Pamplona31006 Spain

ISBN: (纸本)9783952417379

When the process uncertainty size increases, even linear minimum phase systems must sacrifice desirable aggressive feedback control benefits to avoid an excessive 'cost of feedback', while preserving the robust stability. With a suitable uncertainty division and a QFT controller-prefilter to command each uncertainty subset inside a controller-scheduler structure, it is possible to enhance the feedback tracking performance without an excessive bandwidth. To preserve the robust stability from any failure in the switching, each controller is designed to be stable in the whole uncertainty domain, and as accurate in command tracking as desired in its uncertainty subset. © 2003 EUCA.

关键词： Robust control

来源：评论

学校读者我要写书评

暂无评论

Plant uncertainty contribution to QFT Tracking control design 4

Plant uncertainty contribution to QFT Tracking control desig...

引用

4th IFAC Symposium on Robust control Design, ROCOND 2003

作者： Martínez, G.-M. Sanz, G.-M. System Engineering and Automation Group Electrical Engineering Department University of La Rioja Luis de Ulloa. 20 Logrono26004 Spain Automatic Control and Computer Science Department Public University of Navarra Campus Arrosadia s/n Pamplona31006 Spain

Tracking feedback control trade-offs increase dangerously with arbitrarily large uncertainties in the process mode!. This is shown by the bounds in the QFT domain. In this context, the paper develops a theory on the contribution of the plant uncertainty to the tracking QFT bounds through a serious study of tracking bound formulas. From this, a methodology for uncertainty fragmentation is developed. It hopes to loosen the bound toughness, or the control design trade-offs. Better feedback benefits can be achieved while reducing the high-frequency amplification of noises and disturbances at the plant input at the same time. Different QFT controllers in a controller-scheduler structure should drive different uncertainty boundaries. © 2003 IFAC.

关键词： Robust control

来源：评论

学校读者我要写书评

暂无评论

Fuzzy-neuro predictive control, tuned by genetic algorithms, applied to a fermentation process

Fuzzy-neuro predictive control, tuned by genetic algorithms,...

引用

IEEE International Symposium on Intelligent control (ISIC)

作者： J.A. Fabro L.V.R. Arruda Automation and Advanced Control Systems Labratory-LASCA Graduate Program on Electrical Engineering and Applied Computer Science-CPGEI Federal Centre of Technological Education of Paraná Curitiba Parana Brazil

This paper proposes the development of a fuzzy predictive control. Genetic algorithms (GA's) are used to automatically tune the controller. A recurrent neural network is used to identify the process, and then provides predictions about the process behavior, based on control actions applied to the system. These predictions are used by the fuzzy controller, in order to accomplish a better control of an alcoholic fermentation process from chemical industry. This problem has been chosen due to its non-linearity and large accommodation time, that make it hard to control by standard controllers. Comparison of performance is made with non-predictive approaches(PID and Fuzzy-PD), and also with another predictive approach, GPC(Generalized Predictive control).

关键词： Predictive control Genetic algorithms control systems Fuzzy control Alcoholism Recurrent neural networks Nonlinear control systems Artificial intelligence Biomass control system synthesis

来源：评论

学校读者我要写书评

暂无评论

Plant Uncertainty Contribution to QFT Tracking control Design

引用

IFAC Proceedings Volumes 2003年第11期36卷 517-522页

作者： M. Gil-Martínez M. García-Sanz System Engineering and Automation Group Electrical Engineering Department University of La Rioja. Luis de Ulloa 20 26004 Logroño SPAIN. Tf.:+34 941 299496 Automatic Control and Computer Science Department Public University of Navarra. Campus Arrosadía s/n 31006 Pamplona SPAIN Tf.:+34 948 16938

Tracking feedback control trade-offs increase dangerously with arbitrarily large uncertainties in the process model. This is shown by the bounds in the QFT domain. In this context, the paper develops a theory on the contribution of the plant uncertainty to the tracking QFT bounds through a serious study of tracking bound formulas. From this, a methodology for uncertainty fragmentation is developed. It hopes to loosen the bound toughness, or the control design trade-offs. Better feedback benefits can be achieved while reducing the high-frequency amplification of noises and disturbances at the plant input at the same time. Different QFT controllers in a controller-scheduler structure should drive different uncertainty boundaries.

关键词： Quantitative Feedback Theory Robust control Uncertain Dynamical systems

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：