检索结果-内蒙古大学图书馆

Feedback Linearization Based Nonlinear Control Strategy of VSC-HVDC

IFAC Proceedings Volumes 2009年第9期42卷 308-313页

作者： Gengyin Li Ming Yin Ming Zhou Key Laboratory of Power System Protection and Dynamic Security Monitoring and Control under Ministry of Education North China Electric Power University Beijing 102206 P.R. China (Tel: +86 10 80798551) State Power Economic Research Institute Beijing 100761 P.R. China Key Laboratory of Power System Protection and Dynamic Security Monitoring and Control under Ministry of Education North China Electric Power University Beijing 102206 P.R. China

The model of Voltage Source Converter (VSC) based HVDC in the synchronous dq reference frame is presented in this paper. The model includes the DC link model and the VSC models. The feedback linearization principle for Multi-input Multi-output plants is analyzed. Based on the analysis, nonlinear decoupling control strategies for the two VSCs are proposed. For one VSC, the proposed nonlinear control strategy enables it to decouple DC voltage and reactive power control, and for the other one, the strategy guarantees the control of active power and that of reactive power independently. Simulation was conducted with MATLAB/Simulink software to verify the proposed control strategies. The simulation results prove that the nonlinear decoupling control strategies are able to provide good performance.

关键词： Feedback linearization HVDC nonlinear control strategy voltage source converter (VSC)

来源：评论

学校读者我要写书评

暂无评论

Measurement of micro-scale two-phase flow in a pulsating heat pipe using electrical capacitance tomography

引用

Zhongguo Dianji Gongcheng Xuebao/Proceedings of the Chinese Society of Electrical Engineering 2009年第17期29卷 103-107页

作者： Li, Jing-Tao Xiao, Hai-Ping Dong, Xiang-Yuan Liu, Shi Key Laboratory of Power System Protection and Dynamic Security Monitoring and Control North China Electric Power University Changping District Beijing 102206 China School of Energy and Environmental Engineering Zhongyuan Institute of Technology Zhengzhou 450007 Henan Province China

The electrical capacitance tomography (ECT) system was used to the visualization of the two-phase flow as well as the measurement of the film thickness in a pulsating heat pipe (PHP). The new-developed micro-sensor was also applied as a part of the flow channel, with the characteristics of heat transfer and hydrodynamics similar to the measured tube. The measurement accuracy and the image resolving power were improved as compared with the conventional sensors. So the applied area of the ECT technology was widened. The experimental results indicate that there might exist three flow patterns, i.e. bubble-liquid slug flow, semi-annular flow and annular flow, corresponding to different operating conditions. The measurement results of the film thickness compare well with the actual conditions, and the trend of the film thickness can realize the identification of the flow patterns.

关键词： Two phase flow

来源：评论

学校读者我要写书评

暂无评论

A fault location scheme based on spectrum characteristic of fault-generated high-frequency transient signals

A fault location scheme based on spectrum characteristic of ...

引用

IEEE General Meeting power& Energy Society

作者： S. F. Huang X. G. Wang Laboratory of Power System Protection and Dynamic Security Monitoring and Control under Ministry of Education North China Electric Power University Beijing China

When a fault occurs on a transmission line, fault-generated high-frequency signals contains a lot of information about fault. This paper proposes a fault location scheme for transmission lines based on spectrum characteristic of high-frequency components, the difference of adjacent two natural frequencies in one ends of transmission line is used to compute fault distance. This method need not identify arriving time of first traveling wave and traveling wave from fault point, it is insensitive to swings, fault type, fault resistance and system source parameters. The scheme performance was proven using power system computer aided design (PSCAD) simulations in 500-kV power system considering critical fault cases.

关键词： Fault location power transmission lines PSCAD power system simulation power system transients Frequency Fault diagnosis Computational modeling Computer simulation power system faults

来源：评论

学校读者我要写书评

暂无评论

Method for PD location in oil combining ultrasonic phased array with wideband array signal processing

引用

Zhongguo Dianji Gongcheng Xuebao/Proceedings of the Chinese Society of Electrical Engineering 2009年第28期29卷 13-17页

作者： Xie, Qing Li, Yan-Qing Lü, Fang-Cheng Li, Cheng-Rong Wang, Nan Ding, Yu-Jian Key Laboratory of Power System Protection and Dynamic Security Monitoring and Control North China Electric Power University Changping District Beijing 102206 China Beijing Key Laboratory of High Voltage and EMC North China Electric Power University Changping District Beijing 102206 China China Electric Power Research Institute Haidian District Beijing 100192 China

A new method for partial discharge (PD) location in oil is presented based on ultrasonic phased array and wideband array signal processing. Firstly, the wideband ultrasonic signal of PD is measured directly by the ultrasonic phased array sensor and the array signal model is formed. Secondly, according to the frequency characteristic of the ultrasonic signal between 50 kHz to 300 kHz, the method of rotational signal subspace (RSS) is used to focus processing, which can convert the signal direction matrix under different frequencies to the same center frequency by focusing matrix. RSS can reserve the information maximally to realize the direction information accumulation of wideband signals. Finally estimation and location of the PD source signal's direction of arrival (DOA) are realized by means of the multiple signal classification (MUSIC) and crossover locating principle. The method is validated by the results of the experimental research. © 2009 Chin. Sco. for Elec. Eng.

关键词： Location

来源：评论

学校读者我要写书评

暂无评论

Comparison of pitch angle control models of wind farm for power system analysis

Comparison of pitch angle control models of wind farm for po...

引用

IEEE General Meeting power& Energy Society

作者： Li. Lin Jing. Zhang Yihan. Yang Key Laboratory of Power System Protection and Dynamic Security Monitoring and Control Ministry of Education North China Electric Power University Beijing China North China Grid Corporation Beijing China

With rapid development of wind power generation, the large capacity wind farms are built up and integrated into transmission network. The effect of wind farms on the grid becomes more serious and more extensive. In order to investigate the dynamic performances of the grid-connected wind farm and the interaction of the wind farms, it is necessary to present the appropriate models of wind farms, which can present the wind power characteristics completely and are not too complicated. In this paper, based on the detailed model of the pitch angle control system, two kinds of simplified pitch angle control models are deduced by mathematics equivalence method. Then the three models are adopted respectively, the relatively dynamic characteristics of the wind farm and the grid are compared. Later, the wind farm with different pitch angle control model is connected to the CIGRE B4-39 grid, and the simplified models are verified by simulation. Finally, the methods how to choice pitch angle control models are present.

关键词： power system modeling Wind farms power system analysis computing power system control power systems power system dynamics Mathematical model Wind power generation Wind energy Control system synthesis

来源：评论

学校读者我要写书评

暂无评论

Comparison of reactive power compensation strategy of wind farm based on optislip wind turbines

Comparison of reactive power compensation strategy of wind f...

引用

International Conference on Sustainable power Generation and Supply, SUPERGEN

作者： Li Lin Feng Sun Yihan Yang Qunju Li Key Laboratory of Power System Protection and Dynamic Security Monitoring and Control Ministry of Education North China Electric Power University Beijing China North China Electric Power Science Institute Beijing China

The paper studies reactive power compensation strategy of wind farm based on optislip wound rotor induction generators (WRIGs). The WRIGs wind farm shares high market occupancy in China, but academic researches on this grid-connected wind generation are few. Due to the WRIGs wind turbines not allowing the control of the reactive power, so it is necessary that reactive power compensation device is adopted in the large scale grid-connected wind farm. In the paper, from the perspective of system study, the compensation effects of three kind of static var compensation (SVC) are compared, and the influence of different ratings SVC on the voltage stability of the optislip wind farm is investigated. Finally, reactive power compensation strategy of the wind farm is proposed.

关键词： Reactive power Wind farms Wind turbines Induction generators Reactive power control Static VAr compensators Wounds Rotors Mesh generation Wind energy generation

来源：评论

学校读者我要写书评

暂无评论

A novel active islanding detection method based on current-disturbing

A novel active islanding detection method based on current-d...

引用

International Conference on Electrical Machines and systems (ICEMS)

作者： Peng Li Yinbo Sheng Ling Zhang Xilei Yang Yishu Zhao Key Laboratory of Power System Protection and Dynamic Security Monitoring and Control under Ministry of Education North China Electric Power University Baoding China Shandong Electric Power Research Institute Jinan China

Desired islanding detection method not only can detect islanding within acceptable duration, but also require it has less adverse impact on power quality. This paper presents an active islanding detection method for a distributed resource (DG) unit which is coupled to a utility grid through grid-connected converter. With the proposed method which is based on adding periodical disturbing current through current controller of the interface voltage-sourced inverter, islanding can be effectively detected. But when the disturbing current remains unchanged, this method still has some shortages, so this article improved it and used a changed time-varying disturbing current ending with faster detecting time and less disturbing. The studies reported in this paper are based on time-domain simulations in the PSCAD/EMTDC environment. And the results show that the proposed islanding detection method always meets the two-second UL detection requirement.

关键词： Voltage control Inverters Control systems power systems power conversion Frequency Condition monitoring Laboratories power system protection power system dynamics

来源：评论

学校读者我要写书评

暂无评论

Simulation and comparison of transient stability of power system including DFIGs wind farm based on detailed model

Simulation and comparison of transient stability of power sy...

引用

International Conference on Sustainable power Generation and Supply, SUPERGEN

作者： Li Lin Hongjing Hou Wenxia Li Sheng Jing Key Laboratory of Power System Protection and Dynamic Security Monitoring and Control Ministry of Education North China Electric Power University Beijing China Production & Technology Department Zhumadian Electric Power Company Henan China

This article is concerned with the impact of large-scale wind farms utilizing double fed induction generator (DFIG) on the transient stability to a general power system. In the first instance, the synthetical dynamic model of the wind turbine generators (WTGs) is introduced, including pitch angle control model and the generator protective model. And then, the simulation is made to the CIGRE B4-39 standard grid through the comparison between synchronous generator integration and wind farm based DFIG integration with the same power capacity. The simulation is also contained after the load and the topological structure changed. The conclusion shows that the transient stability of the power system including DFIGs wind farm is more robust than conventional synchronous generator connected.

关键词： power system simulation power system transients power system stability power system modeling Wind farms power system dynamics Induction generators power system protection Wind energy generation Synchronous generators

来源：评论

学校读者我要写书评

暂无评论

Design of PV Array Model Based On EMTDC/PSCAD

Design of PV Array Model Based On EMTDC/PSCAD

引用

IEEE PES Asia-Pacific power and Energy Engineering Conference (APPEEC)

作者： Jinhui Xue Zhongdong Yin Bingbing Wu Jun Peng Key Laboratory of Power System Protection and Dynamic Security Monitoring and Control under Ministry of Education North China Electric Power University Beijing China North China Electric Power University Beijing Beijing CN

Along with consuming of fossil energy step by step, crisis of energy has been appeared. The solar energy, which is endless, is a kind of renewable energy. Radiation of sun coming to earth in a day is equal to the energy, which is released by trillion buckets of oil. The research of solar energy generation has stepped into a very activity period. This paper analyses the physics characteristic of photovoltaic array firstly, then researches the mathematical model applying in engineering, and designs the total simulation model based on power electronic circuit in the end. In order to validate the correctness and validity, this paper makes a simulation as an example. The scheme can express the V-I characteristic of photovoltaic array very well.

关键词： EMTDC PSCAD Solar power generation Solar energy Photovoltaic systems Mathematical model Circuit simulation Renewable energy resources Sun Earth

来源：评论

学校读者我要写书评

暂无评论

A method of tracking voltage flicker envelope real-time

A method of tracking voltage flicker envelope real-time

引用

IEEE General Meeting power& Energy Society

作者： Xiufang Jia Qing Chen Key Laboratory of Power System Protection and Dynamic Security Monitoring and Control under Ministry of Education North China Electric Power University Baoding Hebei China North China Electric Power University Baoding Hebei China

Fast and accurate tracking of voltage flicker envelope is significant to the performance of flicker meter, flicker source location and the mitigation of voltage flicker. Using the energy of a signal and its shifted signals to track the envelope of voltage flicker is presented in this paper. It is assumed that the signal is shifted, once by a lead angle equal to beta, and at another time by a lag angle equal to beta, which generates two new signals u + (t) and u - (t). According to the energy differences, the relationship between the flicker amplitude and u(t), u + (t), u - (t) can be obtained, so the voltage flicker envelope is successfully tracked. How to obtain the shifted signals u + (t), u - (t) is analyzed in the paper. The frequency error e f (%), amplitude error e m (%) and waveform standard deviation sigma(%) are used as the weighing index of the accuracy of tracking flicker envelope. The theoretical analyzing and RTDS simulation test verify that the suggested method is accurate, fast and anti-noise.

关键词： Voltage fluctuations Frequency Signal analysis Envelope detectors power quality Wavelet transforms Narrowband Filters Blind source separation Noise reduction

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：