检索结果-内蒙古大学图书馆

3rd International Conference on Deregulation and Restructuring and power Technologies, DRPT 2008

作者： Ming, Zhou Yajing, Gao Gengyin, Li IEEE Key Laboratory of Power System Protection and Dynamic Security Monitoring and Control Ministry of Education North China Electric Power University Changping 102206 Beijing China

ISBN: (纸本)9787900714138

Demmand Side Management (DSM) is now an important consideration for electric power utilities. DSM in general refers to any activity adopted by an electric utility that ultimately changes the utility's system load curve. Enhancing the DSM activities could help not only the system operate more efficiently, but also benefit the system Available Transfer Capability (ATC). This paper presents an integrated framework for evaluating impacts of DSM on ATC. A set of load management models for peak clipping/shifting and valley filling, strategic conservation and strategic load growth are presented. Composite DSM actions in the power system's diverse areas are also modeled. ATC evaluation procedure incorporated with DSM resources is given in sequential Monte Carlo simulation. The Liner-programming based ATC calculation model and time-varying load curves are employed to calculate ATC indices. The IEEE-RTS79 is used to illustrate the proposed approach and implement comparisons of impacts with and without DSM activity on ATC indices. © 2008 DRPT.

关键词： Demand side management

来源：评论

学校读者我要写书评

暂无评论

Nonlinear PID controller of H-bridge cascade SSSC top level control

Nonlinear PID controller of H-bridge cascade SSSC top level ...

引用

3rd International Conference on Deregulation and Restructuring and power Technologies, DRPT 2008

作者： Zhao, Yang Xiao, Xiangning Xudong, Jia IEEE Key Laboratory of Power System Protection and Dynamic Security Monitoring and Control Ministry of Education North China Electric Power University Changping 102206 Beijing China

ISBN: (纸本)9787900714138

As a series FACTS device based on Voltage Source Converter (VSC), Static Series Synchronous Compensators (SSSC) can optimize power flow and improve power system stability by controlling the line impedance rapidly. According to the three levels control structure of SSSC proposed in this paper, when SSSC middle level control operates at constant impedance mode, it has characteristic of controllable impedance as viewed from the top level. In this paper, the output of SSSC is equivalent to controllable impedance and then affine nonlinear equation of the single machine infinite bus (SMIB) power system including a SSSC can be obtained without the compound coordinate transformation approach which is proposed by other documentation and the feedback exact linearization method can be used directly to obtain the SSSC top level nonlinear controller. For avoiding solving the partial differential equation, the direct method is used to realize the exact linearization simply and conveniently. For overcome the shortcoming of low robustness of exact feedback linearization approach due to uncertainty of parameters and model of controlled system, the nonlinear PID control is used to design the SSSC top level controller. Finally the paper applies Real Time Digital Simulator (RTDS) to validate the feasibility of the proposed modeling and control approach in damping out power system oscillations. © 2008 DRPT.

关键词： Nonlinear equations

来源：评论

学校读者我要写书评

暂无评论

Comparison between Hilbert space based power theory and Traditional power theory

Comparison between Hilbert space based power theory and Trad...

引用

2008 Joint International Conference on power system Technology powerCON and IEEE power India Conference, powerCON 2008

作者： Fei, Wang Zengqiang, Mi Qixun, Yang Key Laboratory of Power System Protection and Dynamic Security Monitoring and Control Ministry of Education North China Electric Power University Baoding 071003 Hebei Province China

ISBN: (纸本)9781424417629

The comparison between Hilbert space based power theory and three other power theories including traditional power theory , instantaneous power theory put forward by Akagi and Fryze power theory are analyzed in this paper. Theconsistency and difference are indicated in several different aspects: physical meaning, mathematical concept and the derivation of expressions. Analyses shows that traditional power theory can be regarded as a special case of Hilbert space based power theory, in other words, Hilbert space based power theory can be regarded as the generalization of traditional power theory. Fryze power theory is in accordance with Hilbert space based power theory in single-phase nonsinusoidal system, instantaneous power theory is in accordance with Hilbert space based power theory in three- phase symmetrical system without zero-sequence component. The definition of active current in Hilbert space based power theory is different from it in instantaneous power theory in three-phase system. © 2008 IEEE.

关键词： Hilbert spaces

来源：评论

学校读者我要写书评

暂无评论

Closed loop test platform for SVC controller based on RTDS

Closed loop test platform for SVC controller based on RTDS

引用

11th International Conference on Electrical Machines and systems, ICEMS 2008

作者： Xiangning, Xiao Yang, Zhao Yan, Zhang Meng, Ye Xiaoning, Wang Key Laboratory of Power System Protection and Dynamic Security Monitoring and Control North China Electric Power University Ministry of Education Beijing China Beijing Electric Power Corporation Beijing 100020 China

ISBN: (纸本)9787506292214

Real time test is a necessary step for the control device of equipment before it is installed in power system. In this paper, a closed-loop test platform which is based on Real Time Digital Simulator (RTDS) is established to test the performance of FACTS device controller. In this paper, Static Var Compensator (SVC) which is installed in a power plant is used for damping Sub Synchronous Oscillation (SSO) excited by fixed series compensator installed in the transmission line which is to improve the power transfer capability. The control approach, operation mode and the install location of SVC are studied in this paper and the real controller performance has been verified by the proposed test platform. Beside, this platform can also used for the test of performance of other FACTS devices controller.

关键词： Static Var compensators

来源：评论

学校读者我要写书评

暂无评论

Improved differential evolution algorithm for economic dispatch of power systems

引用

Zhongguo Dianji Gongcheng Xuebao/Proceedings of the Chinese Society of Electrical Engineering 2008年第10期28卷 100-105页

作者： Liu, Zi-Fa Zhang, Jian-Hua Key Laboratory of Power System Protection and Dynamic Security Monitoring and Control North China Electric Power University Beijing 102206 China

An improved differential evolution (IDE) algorithm was presented for power system load economic dispatch (ED), a classical nonconvex, nonlinear, combinational optimization problem. Despite for its simplicity and high-efficiency, differential evolution (DE) algorithm is prone to local optimal solution sometimes. Based on analysis of DE searching mechanism, IDE algorithm adopts adaptive control parameters according to swarms' distribution condition and the overlapping individuals undertake chaotic searching to improve its robust and global optima searching capability. The proposed IDE algorithm was tested on two systems consisting of 3, 40 and 69 thermal units whose incremental fuel cost function took into account the valve-point effects. The results indicate that IDE algorithm outperforms DE, GA, and PSO algorithms in solving load dispatch problems.

关键词： Electric power systems

来源：评论

学校读者我要写书评

暂无评论

control strategy of VSC-HVDC in dual-infeed HVDC systems

引用

Zhongguo Dianji Gongcheng Xuebao/Proceedings of the Chinese Society of Electrical Engineering 2008年第7期28卷 97-103页

作者： Zhao, Cheng-Yong Sun, Ying Li, Guang-Kai Key Laboratory of Power System Protection and Dynamic Security Monitoring and Control North China Electric Power University Baoding 071003 China

Aim at the stability problem of multi-infeed direct current (MIDC) systems, voltage source converter based HVDC (VSC-HVDC) was applied to MIDC systems for improving the voltage characteristic of common AC bus in MIDC systems. A physical model of a dual-infeed HVDC and VSC-HVDC system was set up, and its mathematical model was developed. The rectangular coordinate form of VSC's power transmission equations was deduced through coordinate conversion. Based on the inverse system method for multivariable nonlinear control, the nonlinear controllers of VSC-HVDC system were designed. Simulation results performed on PSCAD/EMTDC show that the designed nonlinear controllers of VSC-HVDC can improve effectively the dynamic character of VSC-HVDC system, stabilize effectively the voltage of dual-infeed HVDC and VSC-HVDC system when AC side is disturbed, reduce the probability of commutation failure in the inverter of HVDC systems, and increase the operation reliability of HVDC systems.

关键词： HVDC power transmission

来源：评论

学校读者我要写书评

暂无评论

New algorithm to distinguish the transferring fault of transformer protection based on morphological gradient

引用

Zhongguo Dianji Gongcheng Xuebao/Proceedings of the Chinese Society of Electrical Engineering 2008年第22期28卷 75-80页

作者： Zheng, Tao Gu, Jun Huang, Shao-Feng Wang, Zeng-Ping Key Laboratory of Power System Protection and Dynamic Security Monitoring and Control North China Electric Power University Beijing 102206 China

Distinguishing the transferring fault is one of difficulties for transformer differential protection. According to CT (current transformer) saturation characteristic, a new algorithm of distinguishing the transferring fault is put forward. As the primary current of CT crosses zero, a small linear transmission part of CT would appear, no matter how CT saturated. Based on this characteristic, the waveform of the differential current would expose discontinuous parts when an external fault occurred;in contrast, this phenomenon would not appear for an internal fault. The morphological gradient is adopted to deal with the waveform between two adjacent extremal points of the differential current. By dividing the gradient waveform into three parts and calculating each part's area, the discontinuous in the differential current could be detected according to the relative size of three above areas. By judging whether the discontinuous parts are existed in the differential current, the transferring faults could be easily distinguished. Simulation results show that this algorithm can distinguish the internal fault, external fault and the fault transferred from the external to the internal under the condition of CT saturation.

关键词： Electric instrument transformers

来源：评论

学校读者我要写书评

暂无评论

Phase-selector based on voltage modal fault component

引用

Dianli Xitong Zidonghua/Automation of Electric power systems 2008年第9期32卷 42-46+99页

作者： Wang, Xingguo Huang, Shaofeng Liu, Qiankuan Key Laboratory of Power System Protection and Dynamic Security Monitoring and Control North China Electric Power University Beijing 102206 China

The characteristics of voltage modal transformation based on fault component in fault location and protection location are discussed in detail with regard to the changes of the system parameters and fault types. A new phase-selector based on voltage modal fault component is proposed. It uses voltage fault component and works fast after a fault occurs. A fault selection scheme is also proposed to solve problems of sensitivity as faults located on remote end of transmission lines. The simulation results of ATP and MATLAB show the feasibility of the scheme.

关键词： Electric power systems

来源：评论

学校读者我要写书评

暂无评论

dynamic state estimator based on WAMS during power system transient process

引用

Zhongguo Dianji Gongcheng Xuebao/Proceedings of the Chinese Society of Electrical Engineering 2008年第7期28卷 19-25页

作者： Qin, Xiao-Hui Bi, Tian-Shu Yang, Qi-Xun Key Laboratory of Power System Protection and Dynamic Security Monitoring and Control North China Electric Power University Beijing 102206 China

As a measurement tool, wide area measurement system (WAMS) has the measurement error and bad data unavoidably. If the raw data is applied direcdy, the unpredictable consequence will be resulted in. Aiming at this problem, a novel dynamic state estimator for generator state variables is proposed. The mathematical model and the flowchart of the algorithm are described. Bad data detection and elimination approach is given as well. The simulation results show that the proposed method can provide the estimated trajectories of the generators in real-time, which eliminates the impact of measurement error and bad data and gives the backbone for WAMS based dynamic applications and real-time control.

关键词： Electric power systems

来源：评论

学校读者我要写书评

暂无评论

Calculation of circulating current in delta winding of transformers with Y, d connection

引用

Dianli Xitong Zidonghua/Automation of Electric power systems 2008年第24期32卷 60-64页

作者： Xia, Shiwei Zheng, Tao Key Laboratory of Power System Protection and Dynamic Security Monitoring and Control North China Electricity Power University Beijing 102206 China

It is difficult to measure the circulating current in delta windings of Y, d connected transformer. So the current phase compensation has to be considered for transformer differential protection. In this study, a proportional relationship between the zero sequence current in Y winding and circulating current in delta winding is derived based on the differential equations of transformer. If phase A is closed exactly in 90 by controlled switching, the part of the line current of phase A is almost equal to the circulating current. By using the correlative formula, the correlative coefficient of line current of phase A and zero sequence current in Y side is calculated so as to distinguish parts of line current, with and without influence of inrush. Then the ratio between the zero sequence current and the circulating current, and the circulating current can be calculated as well. Finally the algorithm is verified with MATLAB and RTDS simulation. The results show that the calculated circulating current is identical with the actual one accurately, and it offers a new algorithm method for the differential protection and the equivalent transient inductance.

关键词： Winding

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：