检索结果-内蒙古大学图书馆

Constrained spectral clustering based controlled islanding

INTERNATIONAL JOURNAL OF ELECTRICAL power & ENERGY systemS 2014年 63卷 687-694页

作者： Ding, Lei Wall, Peter Terzija, Vladimir Shandong Univ Key Lab Power Syst Intelligent Dispatch & Control Minist Educ Jinan 250061 Peoples R China Univ Manchester Sch Elect & Elect Engn Manchester M13 9PL Lancs England

controlled islanding, which splits the whole power system into islands, is an effective way of limiting blackouts during severe disturbances. Calculating islanding solutions in real time is difficult because of the combinatorial explosion of the solution space occurs for large power system. This paper proposes a computationally efficient controlled islanding algorithm that uses constrained spectral clustering. An undirected edge-weighted graph is constructed based on absolute values of active power flow and constraints related to transmission line availability and coherent generator groups are included by modifying the edge weights of the graph and using a subspace projection. Spectral clustering is then applied to the constrained solution subspace to find the islanding solution. To improve the clustering quality,.a pre-processing procedure is used to detect and eliminate outliers in the eigenvectors of the graph before clustering. A robust k-medoids algorithm, which is less sensitive to outliers than the traditional k-means algorithm, is then used for clustering. Simulation results show that the proposed algorithm is computationally efficient when solving a controlled islanding problem in real-time. (C) 2014 Elsevier Ltd. All rights reserved.

关键词： Constrained spectral clustering controlled islanding Graph theory

来源：评论

学校读者我要写书评

暂无评论

Generalized Impedance-based Fault Distance Calculation Mehtod for power Distribution systems 6

Generalized Impedance-based Fault Distance Calculation Mehto...

引用

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

作者： Sun, Kongming Chen, Qing Gao, Zhanjun Liu, Dawei Zhang, Gonglin Shandong Univ Minist Educ Key Lab Power Syst Intelligent Dispatch & Control Jinan Peoples R China State Grid Fujian Elect Power Res Inst Fuzhou Peoples R China

ISBN: (纸本)9781479975372

This paper presents a new impedance-based fault distance calculation formulation for power distribution systems. The majority of low-or medium-voltage distribution systems are characterized by having numerous branches, laterals and sub-laterals, highly unbalanced operation, and time varying load profile. All of these and other characteristics make most efficient approaches proposed for fault location in power distribution systems not applicable to distribution systems. The proposed method uses only measurements of voltage and current at the beginning of the analyzed feeder, and additional equipments such as, fault locators and monitoring devices are not needed to be installed in the distribution system. The apparent impedance is calculated by using the fundamental rms values of the measured voltage and current in this paper. This method is suitable to any kinds of fault and can be used to unbalanced power distribution systems, since it is derived in phase domain.

关键词： Fault location Impedance based method power distribution system

来源：评论

学校读者我要写书评

暂无评论

Real-time dispatch Based on Effective Steady-state Security Regions of power systems

Real-time Dispatch Based on Effective Steady-state Security ...

引用

IEEE power and Energy Society General Meeting

作者： Fenglu Cheng Ming Yang Xueshan Han Jun Liang Key Laboratory of Power System Intelligent Dispatch and Control of Ministry of Education

ISBN: (纸本)9781479964161

As the regulating range is limited in the real-time dispatch, the security improvement is more prominent than the economic improvement for the real-time dispatch. Based on the preemptive goal programming and the steady-state security region estimation methods, this paper proposed a model for the real-time dispatch, in which the base-points and the participation factors of the AGC (Automatic Generation control) units are co-optimized. The model has two goals. One is to maximize the ability of the power system to depress the load disturbances by maximizing the overlap region of the steady-state security region and the load variation region (named as the effective steady-state security region). The other one is to minimize the operating costs including the generation costs and the reserve costs. By setting the first goal as the preemptive goal, the economic dispatch results are obtained with respected to the maximized effective steady-state security region. Numerical tests demonstrate the effectiveness of the proposed approach.

关键词： power systems Robust dispatch Real-time dispatch Steady-state security region

来源：评论

学校读者我要写书评

暂无评论

An ANN Strategy for Luminance control of LED in Response to power system Frequency

An ANN Strategy for Luminance Control of LED in Response to ...

引用

International Conference on power system Technology (powerCon)

作者： Gao, Liqiang Wei, Zhongkang Chu, Xiaodong Zhang, Wen Shandong Univ Key Lab Power Syst Intelligent Dispatch & Control Minist Educ Jinan 250061 Peoples R China State Grid Jibei Elect Power Co Beijing 100053 Peoples R China

ISBN: (纸本)9781479950324

controllable load can actively participate in power balance control, which will have positive impact on power system operation. Lighting load takes a significant proportion in the electricity demand. Many features of Light emitting diodes (LEDs), small size, high luminous efficiency and long lifetime, make them very attractive for use in lighting. An Artificial Neural Network (ANN) control strategy is designed for LED luminance control in response to power system frequency. The pulse width modulation (PWM) dimming method is used to realize luminance control of LED. In order to regulate the LED power demand in response to frequency measurement signal, the ANN control strategy adjusts the ratio between the on-time and off-time of the PWM dimming signal of LED. Simulations are conducted to verify the effectiveness of the proposed the ANN control strategy.

关键词： LED luminance control constant current control Artificial Neural Network power system frequency

来源：评论

学校读者我要写书评

暂无评论

An Approach to User-defined Modeling Implemented with MATlab 6

An Approach to User-defined Modeling Implemented with MATLAB

引用

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

作者： Xu, Xin Zhang, Hengxu Xu, Qun Shandong Univ Minist Educ Key Lab Power Syst Intelligent Dispatch & Control Jinan 250061 Peoples R China Shandong Elect Power Corp Qingdao Power Supply Co Qingdao 266002 Peoples R China

ISBN: (纸本)9781479975372

User-defined modeling helps a lot in enhancing the flexibility of power system numerical simulation. A user-defined modeling scheme is proposed to extend power system numerical simulation capabilities. It is implemented with MATlab, which can fully use the numerical calculation and visual modeling functions of MATlab. Therefore, the simulation and analysis abilities of power system simulation software package can be effectively enhanced. The case shows the feasibility and effectiveness of this approach.

关键词： power system MATlab numerical simulation user-defined modeling

来源：评论

学校读者我要写书评

暂无评论

Coordinated control Strategy of Air-conditioning Loads for power system Balancing

Coordinated Control Strategy of Air-conditioning Loads for P...

引用

International Conference on power system Technology (powerCon)

作者： Liu, Meng Wei, Zhongkang Chu, Xiaodong Zhang, Wen Shandong Univ Minist Educ Key Lab Power Syst Intelligent Dispatch & Control Jinan 250061 Peoples R China State Grid Jibei Elect Power Co Beijing 100053 Peoples R China

ISBN: (纸本)9781479950324

In this paper a coordinated control strategy of air-conditioning load groups is proposed to help correct imbalances between load and generation, especially when the power system is under stressed conditions such as the loss of power generation. Firstly, a decentralized air-conditioning load group control strategy (control mode 1) is presented accounting for maintenance of load diversity, so that the large oscillations of aggregated power of load group caused by diversity loss can be avoided. However, there is an unwanted parasitic "power peak" in the control mode 1. To eliminate the negative effects of the "power peak", another load control strategy (control mode 2) is borrowed from the literature which requires to communicate with the control center. Both of the control modes 1 and 2 adopt a segmental load recovery scheme to avoid "recovery peak". Then, a coordinated load control strategy is presented to coordinate the control modes 1 and 2. The "power peak" in control mode 1 is used as the power control objective for the load group of the control mode 2, and the control signal for control mode 2 can be calculated using the dichotomy method. Simulation results verify the effectiveness of the proposed coordinated control strategy of air-conditioning loads for power system balancing.

关键词： coordinated control dichotomy method load control load diversity

来源：评论

学校读者我要写书评

暂无评论

Fast DC Component Suppression Method for Phase Locked Loop

Fast DC Component Suppression Method for Phase Locked Loop

引用

29th Annual IEEE Applied power Electronics Conference and Exposition (APEC)

作者： Ma, Cong Gao, Feng He, Guoqing Li, Guanghui Shandong Univ Minist Educ Key Lab Power Syst Intelligent Dispatch & Control Jinan 250100 Peoples R China Inst New energy China Elect Power Res Beijing Peoples R China

ISBN: (纸本)9781479923250

The reasons of measured grid voltage signals including dc components in the grid-tied applications could be the original input signal with dc component, the zero drift of detecting elements and converters, or the grid system fault. When the measured grid voltage has the undesired dc component, the low frequency oscillation would appear in the traditional phase locked loop (PLL) and in consequence induce the inaccuracy of calculated phase angle and amplitude. A traditional method to eliminate the DC component in the measured AC signal is to convert the AC signals to DQ components in the synchronous reference frame and then assume a low-pass filter with the low cut off frequency to filter out the low order harmonics added in the converted dc signals, which however would unavoidably prolong the system response time and is unsatisfied in those applications need fast reaction function. This paper proposes a fast dc component suppression method for the phase locked loop, which can fast filter out the dc component appeared in the sampled AC signal. Moreover, the proposed PLL can keep the fast and accurate calculation of fundamental voltage amplitude and phase angle even though the harmonic distortion occurs. Simulation and experimental results verified the effectiveness of the proposed method.

关键词： circuit oscillations harmonic distortion low-pass filters phase locked loops power convertors DQ component PLL amplitude calculation converter fast DC component suppression method frequency oscillation grid system fault grid-tied application low order harmonics distortion low-pass filter measured AC signal measured grid voltage signal phase angle calculation phase locked loop synchronous reference frame Delays Frequency measurement Harmonic analysis Harmonic distortion Phase locked loops power harmonic filters Voltage measurement

来源：评论

学校读者我要写书评

暂无评论

Optimization and Decision for Limiting Short Circuit Current Considering Sensitivity Ranking

Optimization and Decision for Limiting Short Circuit Current...

引用

International Conference on power system Technology (powerCon)

作者： Yang, Dong Zhao, Kang Zhao, Yan Liu, Yutian State Grid Shandong Elect Power Res Inst Jinan Peoples R China Shandong Univ Minist Educ Key Lab Power Syst Intelligent Dispatch & Control Jinan 250100 Peoples R China

ISBN: (纸本)9781479950324

Limiting short circuit current and increasing power system stability is a contradiction. An optimization and decision model for limiting short circuit current considering sensitivity ranking is established. Firstly, the influence on impedance matrix caused by current limiting measures is analyzed, and a variable selection strategy considering the sensitivity relation between current limiting measures and node self-impedance is proposed. Secondly, the objective functions which minimize the total investment costs and the short circuit capacity margin are presented, and an adaptive hybrid particle swarm optimization algorithm is used to find a scheme set. Finally, a comprehensive evaluation model is established based analytic hierarchy process and the systematic and quantitative assessments are realized by the fuzzy algorithm. Simulation results of the practical power grid demonstrated the efficiency and speediness of this proposed model.

关键词： Analytic hierarchy process fuzzy comprehensive evaluation particle swarm optimization sensitivity analysis short circuit current

来源：评论

学校读者我要写书评

暂无评论

Analysis of commutation failure in HVDC caused by AC side fault

引用

Energy Education Science and Technology Part A: Energy Science and Research 2014年第6期32卷 7061-7070页

作者： Li, Gang Li, Ke-Jun Ren, Jing-Guo Wang, Zhuo-Di Zhao, Xiang-Lei Shandong University Key Laboratory of Power System Intelligent Dispatch and Control of Ministry of Education Jinan China

In the AC/DC interconnection system, commutation failure (CF) caused by AC faults is one of the most common inverter faults. In this paper, the mathematical formula is derived from the definition of self/mutual impedance. It can reflect the influence of AC system faults on DC system. The influencing factors of commutation failure are analyzed. Based on engineering parameters, the detailed model of ±660kV Yindong HVDC project is built using PSCAD/EMTDC. The dynamic characteristics of Yindong HVDC system under three-phase short-circuit fault at AC system are simulated and analyzed. © Sila Science. All rights reserved.

关键词： Timing circuits

来源：评论

学校读者我要写书评

暂无评论

Fast Voltage Detection Method for the Voltage Ride Through Operation of Grid-Tied Renewable Energy Generation systems

Fast Voltage Detection Method for the Voltage Ride Through O...

引用

29th Annual IEEE Applied power Electronics Conference and Exposition (APEC)

作者： Ma, Cong Gao, Feng He, Guoqing Li, Guanghui Shandong Univ Minist Educ Key Lab Power Syst Intelligent Dispatch & Control Jinan 250100 Peoples R China China Elect Power Res Inst Inst New Energy Beijing 100192 Peoples R China

ISBN: (纸本)9781479923250

As the scale of renewable energy resources connected to the grid is increasing remarkably, the strict gird codes are formulated in order to ensure the grid safety. Among the grid codes, the low voltage ride through (LVRT) regulation is important because it defines the acquired response to support the grid stability. This paper proposed a new voltage detection method, which consists of the traditional three-phase phase lock loop and a new low voltage detection procedure for the low voltage ride through operation of grid-tied renewable energy generation systems. This method can detect the amplitude of voltage sag within 5ms by tracking either the maximum point or the zero point. Finally, validity and accuracy of the proposed method is verified by simulation and experimental results.

关键词： phase locked loops power grids power supply quality power system stability renewable energy sources signal detection voltage control LVRT regulation gird codes grid safety grid stability grid-tied renewable energy generation systems low voltage detection procedure low voltage ride through regulation renewable energy resources three-phase phase lock loop voltage sag Low voltage Phase distortion Phase locked loops Real-time systems Renewable energy sources Voltage fluctuations

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：