检索结果-内蒙古大学图书馆

power Tech Conference

作者： Wang Jili He Renmu Ma Jin Key Laboratory of Power System Protection and Dynamic Security Monitoring and Control of Ministry of Education North China Electric Power University Beijing China

Distributed generation is regarded as the developing direction of the power system in 21 century. Because distributed generation always connects with the distribution system, which has great influence on every aspects of power system. This paper studied the influence of distributed generation on load modeling. When the influence of distributed generation is not negligible, the composite induction motor load model can't effectively describe the actual load characteristic. This paper proposes a new load model-asynchronous generator +ZIP. The validity of the proposed load model is also testified via the comparison and contrast from a great deal of simulations. Then, composite induction-motor and asynchronous generator +ZIP load models were unified in one program.

关键词： Load modeling Distributed control power system modeling power system dynamics power system simulation Induction generators power systems Helium power system transients power system stability

来源：评论

学校读者我要写书评

暂无评论

A new method for hybrid non-linear state estimation with PMU

引用

Dianli Xitong Zidonghua/Automation of Electric power Systems 2007年第4期31卷 28-32页

作者： Qin, Xiaohui Bi, Tianshu Yang, Qixun Key Laboratory of Power System Protection and Dynamic Security Monitoring and Control North China Electric Power University Beijing 102206 China Sifang Research Institute North China Electric Power University Beijing 102206 China

A new method for hybrid non-linear state estimation with phasor measurement unit (PMU) is proposed, in which the direct voltage phasor measurement is transformed into indirect equivalent branch current measurement to conduct the hybrid iteration with SCADA measurement. The indirect measurement errors caused by constructing the equivalent current modification are also analyzed and calculated in detail. The accuracy of the hybrid estimation algorithm is analyzed qualitatively and calculated quantitatively. The theoretic analysis and simulation results demonstrate that the proposed method has higher estimation precision and better performance in convergence time and filtering effect.

关键词： State estimation

来源：评论

学校读者我要写书评

暂无评论

Modeling of the Wind Turbine with a Permanent Magnet Synchronous Generator for Integration

Modeling of the Wind Turbine with a Permanent Magnet Synchro...

引用

IEEE General Meeting power& Energy Society

作者： Ming Yin Gengyin Li Ming Zhou Chengyong Zhao Key Laboratory of Power System Protection and Dynamic Security Monitoring and Control under Ministry of Education North China electric Power University Beijing China

The paper presents the dynamic model and control schemes of a variable speed pitch wind turbine with permanent magnet synchronous generator (PMSG). The model includes a PMSG model, a pitch-angled controlled wind turbine model and a drive train model. The drive train model uses one-mass model to represent the mechanical characteristics of the generator set. The generator model is established in the dq-synchronous rotating reference frame. The wind turbine model details the mechanism of variable speed operation of the turbine by a pitch control. The control schemes in the paper include a pitch angle control for the wind turbine and a speed control for the generator. The pitch angle control uses wind speeds and electric power output as the input signals to ensure normal operation in high wind speed. The speed control is realized through field orientation where the d-axis current is set to zero and the q-axis current is used to control the rotational speed of the generator according to the variation of wind speed. In order to verify the presented model and the control strategy, simulations with MATLAB/Simulink software have been conducted. Simulation results prove the validity of the model and the control schemes.

关键词： Wind turbines Permanent magnets Synchronous generators Mathematical model Mechanical variables control Electric variables control Wind speed Magnetic variables control Velocity control Wind energy generation

来源：评论

学校读者我要写书评

暂无评论

Sensitivity analysis for AC/DC hybrid power systems

引用

Dianli Xitong Zidonghua/Automation of Electric power Systems 2007年第12期31卷 45-49页

作者： Liu, Chongru Zhang, Boming Key Laboratory of Power System Protection and Dynamic Security Monitoring and Control North China Electric Power University Beijing 102206 China State Key Lab. of Power Systems Department of Electrical Engineering Tsinghua University Beijing 100084 China

The interactions between AC and DC systems in the steady-state condition of power systems are investigated. Through a sensitivity analysis, the influence of DC control parameters on the operation of AC/DC systems and that of AC control parameters on other AC parameters with the DC system existing are discussed. The sensitivity matrices and the influence factors between AC and DC systems are analyzed from various points of view. The sensitivity analysis made in this paper is expected to be of practical significance in such problems as load flow control, parameter regulation, voltage estimation, etc.

关键词： Electric power transmission networks

来源：评论

学校读者我要写书评

暂无评论

Reallocating-damping theory of PSS and HVDC modulation

Reallocating-damping theory of PSS and HVDC modulation

引用

2007 International power Engineering Conference (IPEC2007), vol.2

作者： Shanshan Zhao Li Lin Xiangyu Tao Yonghua Yin Key Laboratory of Power System Protection and Dynamic Security Monitoring and Control and China Electric Power Research Institute North China Electric Power University China Key Laboratory of Power System Protection and Dynamic Security Monitoring and Control Ministry of Education North China Electric Power University Beijing China China Electrical Power Research Institute China

In an AC/DC large-scale interconnection power grid, there are many problems to be solved. Among these, small-signal stability is extremely important. In this paper, based on the reallocating -damping theory of PSS, reallocating-damping theory of HVDC modulation is proposed, that variation of gain of HVDC modulation doesn't influence the system general damping. It is also proved that reallocating-damping theory unifies PSS and HVDC modulation, which are both damping control measures. Mathematics deduction is given in detail. The possible negative effect caused by PSS and HVDC modulation is analyzed. A number of cases are tested such as a 12-generator system, 2DC system and a real power system.

关键词： Low frequency oscillation PSS HVDC modulation Reallocating-damping theory AC/DC hybrid grid Damping characteristics

来源：评论

学校读者我要写书评

暂无评论

Decoupling control for Multiterminal VSC-HVDC Based Wind Farm Interconnection

Decoupling Control for Multiterminal VSC-HVDC Based Wind Far...

引用

IEEE General Meeting power& Energy Society

作者： Gengyin Li Ming Yin Ming Zhou Chengyong Zhao Key Laboratory of Power System Protection and Dynamic Security Monitoring and Control under Ministry of Education North China Electric Power University Beijing China

In the paper multiterminal voltage source converter based HVDC (VSC-HVDC) is proposed to interconnect wind farms to AC grids. The method highlights the control at the level of wind generator cluster that comprises several permanent magnet synchronous generators without the primary converters on themselves. For the cluster control, active and reactive power decoupling scheme is applied to adjust the rotational speed of the cluster according to wind speed. The paper studies the schemes to control grid side converter based on the philosophy of linear decoupling control, which aims to control the DC voltage as well as the reactive power of VSC-HVDC. In the proposed control scheme, the two goals are achieved by controlling the q- and rf-axis components of the grid's fundamental current. Simulation has been performed using engineering software Matlab/Simulink to verify the interconnection method and validate the control scheme as well.

关键词： Wind farms Converters power conversion Voltage control Synchronous generators Reactive power control HVDC transmission Wind energy generation Permanent magnets Wind speed

来源：评论

学校读者我要写书评

暂无评论

Multi-layer Disturbance Processing System based on Multiple Information Sources

Multi-layer Disturbance Processing System based on Multiple ...

引用

IEEE General Meeting power& Energy Society

作者： Tianshu Bi Qian Li Key Laboratory of Power System Protection and Dynamic Security Monitoring and Control under Ministry of Education North China Electric Power University Beijing China

More and more IEDs have been commissioned in power systems, such as digital relays, PMUs, metering and control devices, fault recorders and so on. Once there is a disturbance (for example, fault, low-frequency oscillation, etc.), large amount of information will pour into the control center. Therefore, how to identify the disturbance and then take corresponding countermeasures is crucial for power system security and reliability. A multi-layer disturbance processing system based on multiple information sources is proposed in this paper. Firstly, the characteristics of different kinds of information sources, including PMUs, RTUs, digital relays and fault recorders, are analyzed. Secondly, according to the arrival times of the information, the framework and functions of multi-layer fault diagnosis system is presented in detail. After a disturbance occurs, the suggested system could realize disturbance identification, fault element diagnosis and detailed post-fault analysis in succession at different time frames with the information coming, which fits the needs of operators well.

关键词： Fault diagnosis Digital relays Phasor measurement units power system reliability Information analysis power system faults power system relaying power system control power systems control systems

来源：评论

学校读者我要写书评

暂无评论

Research on identifiability of equivalent motor in composite load model

Research on identifiability of equivalent motor in composite...

引用

2007 IEEE Lausanne powerTECH

作者： Ma, Jin Han, Dong He, Renmu Dong, Zhaoyang Hill, David J. IEEE Key Laboratory of Power System Protection and Dynamic Security Monitoring and Control Ministry of Education North China Electric Power University 102206 Beijing China School of Information Technology and the Electrical Engineering University of Queensland St. Lucia QLD 4072 Australia Department of Information Engineering Australian National University

ISBN: (纸本)9781424421909

Load modeling is very important for power system dynamic analysis and control. The composite load model widely applied recently in the power system operation centre consists of the static load and the equivalent motor. Current practices in measurement-based load modeling identify all the parameters in this composite load model. However, it is not clear whether all these parameters could be identified from the measurements. This paper investigates the identifiability of the equivalent motor parameters in the composite load model. Trajectory sensitivity approach is applied first to find the motor parameters that have great effects on the measured active as well as reactive load dynamics. The analysis results show that the motor outputs have various sensitivities with respect to the parameters. Since the voltage disturbance, the active load and the reactive load dynamics are applied to identify the motor parameters, those parameters affecting the measurements to a great extent are observable, thus identifiable from the measurements;while those that have little effects on the motor outputs are unobservable from the measurements and consequently unidentifiable. The case studies verify the identifiability of the motor parameters. ©2007 IEEE.

关键词： Parameter estimation

来源：评论

学校读者我要写书评

暂无评论

Research on PT Ferromagnetic Resonance Region and the controllable Damping

Research on PT Ferromagnetic Resonance Region and the Contro...

引用

power Tech Conference

作者： L. X. Zhou Z. D. Yin Key Laboratory of Power System Protection and Dynamic Security Monitoring and Control under Ministry of Education North China Electric Power University Beijing China

In the neutral ungrounded system, potential transformer (PT) ferro-magnetic resonance is a kind of interior overvoltage which is frequently appears and creates most of the accidents. Whether the elimination measures are reasonable and effective or not affects the security and stability of the power system directly. Fundamental research has been done on the resonance region changeable situation and the characteristics of each resonance region under different system parameter and PT saturation characteristics. According to the occurring principle of PT ferromagnetic resonance and the characteristics, a novel effective controllable damping device is designed, which will change the correlative parameter that lead to resonance to make the circuit parameter of the system get out of the resonance area to eliminate the resonance. The accuracy of the fundamental analysis and the effectiveness of the elimination measure have been verified by the digital simulation based on EMTDC/PSCAD and by the high voltage propotype experiment.

关键词： Magnetic resonance Damping power system security power system stability PSCAD Voltage transformers Voltage control Accidents power measurement power system measurements

来源：评论

学校读者我要写书评

暂无评论

A Mathematic Model and its Iterative Algorithm on Obtaining Optimal Capacity of P-S Station

A Mathematic Model and its Iterative Algorithm on Obtaining ...

引用

2007 International power Engineering Conference (IPEC2007), vol.1

作者： Fang Cao Li-zi Zhang Key Laboratory of Power System Protection and Dynamic Security Monitoring and Control under Ministry of Education North China Electric Power University Beijing China

With rising electricity loading in developing country, measuring capacity of pumped-storage station (P-S station) is becoming more critical. This paper tries to establish mathematic model on obtaining capacity of P-S station for maximum cost sayings. The paper first deducts the relationship between capacity of P-S station, peak load and the vale load by simulating cost curve of thermoelectric unit, and then deducts the formula for calculating optimal capacity of P-S station. Based upon these findings and the load curve, the paper then develops the curve to describe the relationship between volume of generated electricity and capacity of the P-S station and provides the solution for obtaining optimal capacity of the P-S station. Finally, the paper discusses the impact of selecting initial solution or certain iterative solution on iterative speed and suggests the direction for further research.

关键词： Iterative methods Optimization methods Pumped storage power generation

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：