检索结果-南通市图书馆

Frontiers in Energy 2014年第4期8卷 412-425页

作者： Iraj AHMADIAN Oveis ABEDINIA Noradin GHADIMI west regional electric company-electrical Transmission Department of Ilam Ilam 693 Iran Department of electrical Engineering Ardabil Branch Islamic AzadUniversity Ardabil 045 Iran

This paper presents a novel modified inter- active honey bee mating optimization （IHBMO） base fuzzy stochastic long-term approach for determining optimum location and size of distributed energy resources （DERs）. The Monte Carlo simulation method is used to model the uncertainties associated with long-term load forecasting, A proper combination of several objectives is considered in the objective function. Reduction of loss and power purchased from the electricity market, loss reduc- tion in peak load level and reduction in voltage deviation are considered simultaneously as the objective functions. First, these objectives are fuzzified and designed to be comparable with each other. Then, they are introduced into an IHBMO algorithm in order to obtain the solution which maximizes the value of integrated objective function. The output power orDERs is scheduled for each load level. An enhanced economic model is also proposed to justify investment on DER. An IEEE 30-bus radial distribution test system is used to illustrate the effectiveness of the proposed method.

关键词： component distributed energy resources,fuzzy optimization loss reduction interactive honey beemating optimization (IHBMO) voltage deviation reduction,stochastic programming

Monte-Carlo-based simulation and investigation of 230 kV transmission lines outage due to lightning

在线全文

学校读者我要写书评

暂无评论

High Voltage 2020年第1期5卷 83-91页

作者： Ehsan Karami Ahmad Khalilinia Afshar Bali Kumars Rouzbehi electrical Engineering Department Sharif University of TechnologyTehranIran west regional electric company KermanshahIran Department of System Engineering and Automatic Control University of Seville41004 SevilleSpain

Here,using the probabilistic evaluation based on the Monte Carlo method,back-flashover rate and shielding failure flashover rate of 230 kV overhead transmission lines in the western regions of Iran are *** such an aim,first,the number of thunderstorm days per year is collected from the reported weather information in order to determine the ground flash ***,using MRU-200 equipment,the tower-footing resistance of several towers is ***®software is used in order to produce lightning surges considering its probabilistic nature and randomly distribution on the ground to evaluate striking distance based on the geometric ***,calculated parameters are transferred to EMTP-RV software by establishing a link to perform the transient simulation and report the results for modelled 230 kV transmission ***,considering IEEE-1243 standard,it is shown that due to high ground flash density,using 230 kV tower with one shield wire is not sufficient to protect the line against lightning phenomena.

关键词： flash lightning probabilistic

Attuned design of demand response program and M-FACTS for relieving congestion in a restructured market environment

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Frontiers in Energy 2015年第3期9卷 282-296页

作者： Y. HASHEMI H. SHAYEGHI B. HASHEMI Technical Engineering Department University of Mohaghegh Ardabili Ardabil *** Iran Network Studies Group Bakhtar Regional Electric Company Arak *** Iran

This paper addresses the attuned use of multi- converter flexible alternative current transmission systems （M-FACTS） devices and demand response （DR） to perform congestion management （CM） in the deregulated environment. The strong control capability of the M- FACTS offers a great potential in solving many of the problems facing electric utilities. Besides, DR is a novel procedure that can be an effective tool for reduction of congestion. A market clearing procedure is conducted based on maximizing social welfare （SW） and congestion as network constraint is paid by using concurrently the DR and M-FACTS. A multi-objective problem （MOP） based on the sum of the payments received by the generators for changing their output, the total payment received by DR participants to reduce their load and M-FACTS cost is systematized. For the solution of this problem a nonlinear time-varying evolution （NTVE） based multi-objective particle swarm optimization （MOPSO） style is formed. Fuzzy decision-making （FDM） and technique for order preference by similarity to ideal solution （TOPSIS） approaches are employed for finding the best compromise solution from the set of Pareto-solutions obtained through multi-objective particle swarm optimization-nonlinear time-varying evolution （MOPSO-NTVE）. In a real power system, Azarbaijan regional power system of Iran, comparative analysis of the results obtained from the application of the DR ＆ unified power flow controller （UPFC） and the DR ＆ M-FACTS are presented.

关键词： multi-converter flexible alternative currenttransmission systems (M-FACTS) demand response,

Online coherence identification using dynamic time warping for controlled islanding

在线全文

学校读者我要写书评

暂无评论

Journal of Modern Power Systems and Clean Energy 2019年第1期7卷 38-54页

作者： Hasan Ul BANNA Zhe YU Di SHI Zhiwei WANG Dawei SU Chunlei XU Sarika Khushalani SOLANKI Jignesh M.SOLANKI GEIRI North America Department of CSEE West Virginia University Grid Dispatch Center State Grid Jiangsu Electric Power Company

Controlled islanding is considered to be the last countermeasure to prevent a system-wide blackout in case of cascading *** splits the system into self-sustained islands to maintain transient stability at the expense of possible loss of *** coherence identification is critical to controlled islanding scheme as it helps identify the optimal cut-set to maintain the transient stability of the post-islanding *** paper presents a novel approach for online generator coherency identification using phasor measurement unit(PMU) data and dynamic time warping(DTW).Results from the coherence identification are used to further cluster non-generator buses using spectral clustering with the objective of minimizing power flow *** proposed approach is validated and compared to existing methods on the IEEE39-bus system and WECC 179-bus system, through which its advantages are demonstrated.

关键词： Coherence identification Constrained spectral clustering Controlled islanding Dynamic time warping Phasor measurement unit measurement

Infuences of Different Admixtures on the Drying Shrinkage Characteristics of Metakaolin-based Geopolymer Mortar

在线全文

学校读者我要写书评

暂无评论

Journal of Wuhan University of Technology(Materials Science) 2024年第6期39卷 1425-1433页

作者： ZHI Jing ZHANG Chengyang WANG Yunwen WEI Libao ZHANG Pan State Grid Gansu electric Power company Wuwei Power Supply company Wuwei 733000China State Grid Gansu electric Power company Baiyin Power Supply company Baiyin 730900China

To investigate the influences of different admixtures on the drying shrinkage of polymer mortar in a metakaolin base,the experiments of VAE(vinyl acetate ethylene copolymer),APAM(anionic polyacrylamide)and CPAM(cationic polyacrylamide)on the drying shrinkage properties of geopolymer mortar were designed under normal temperature curing *** SP-175 mortar shrinkage dilatometer was introduced to measure the dry shrinkage of geopolymer ***,the drying shrinkage properties of geopolymer mortar are exhibited by the parameters of water loss rate,drying shrinkage rate,drying shrinkage strain and drying shrinkage *** experimental data are further fitted to obtain the prediction model of dry shrinkage of geopolymer mortar,which can better reflect the relationship between dry shrinkage rate and ***,the experimental results demonstrate that the dry shrinkage of geopolymer mortar can be significantly increased by adding 4%VAE admixture,meanwhile under the condition that the polymer film formed by VAE reaction can strengthen and toughen the mortar.2.5%APAM admixture and 1.5%CPAM admixture can enhance the dry shrinkage performance of geopolymer mortar in a certain range.

关键词： metakaolin base polymer mortar dry shrinkage property admixture dry shrinkage prediction model

An efficient stochastic algorithm for mid-term scheduling of cascaded hydro systems

在线全文

学校读者我要写书评

暂无评论

Journal of Modern Power Systems and Clean Energy 2019年第1期7卷 163-173页

作者： Xiaolin GE Shu XIA Wei-Jen LEE electric Power College Shanghai University of Electric Power Shibei electricity Supply company of State Grid Shanghai Municipal electric Power company Energy Systems Research Center University of Texas at Arlington

Due to the stochastic and correlated attributes of natural inflows, the mid-term generation scheduling problem for cascaded hydro systems is a very challenging *** paper proposes a novel stochastic optimization algorithm using Latin hypercube sampling and Cholesky decomposition combined with scenario bundling and sensitivity analysis(LC-SB-SA) to address this *** deal with the uncertainty of natural inflows, Latin hypercube sampling is implemented to provide an adequate number of sampling scenarios efficiently, and Cholesky decomposition is introduced to describe the correlated natural inflows among cascaded *** addition, to overcome the difficulties in solving the objectives of all the scenarios, scenario bundling and sensitivity analysis algorithms are developed to improve the computational *** results from both two-station and tenstation systems indicate that the proposed method has the merits in accuracy as well as calculation speed for the midterm cascaded hydro generation *** consideration of natural inflow correlation makes the formulated problem more realistic.

关键词： Cascaded hydro systems Mid-term scheduling Stochastic optimization algorithm Correlation Sensitivity

Mathematical methods for main tenance and operation cost prediction based on transfer learning in State Grid

在线全文

学校读者我要写书评

暂无评论

Applied Mathematics(A Journal of Chinese Universities) 2022年第4期37卷 598-614页

作者： GUO Yun-peng WANG Dong-fa ZHENG Ying DING Wei-bin State Grid Zhejiang electric Power company Jinhua Power Supply company Jinhua 321000China State Grid Zhejiang electric Power company Hangzhou 310018China

The electric power enterprise is an important basic energy industry for national development,and it is also the first basic industry of the national *** the continuous expansion of State Grid,the progressively complex operating conditions,and the increasing scope and frequency of data collection,how to make reasonable use of electrical big data,improve utilization,and provide a theoretical basis for the reliability of State Grid operation,has become a new research hot *** electrical data has the characteristics of large volume,multiple types,low-value density,and fast processing speed,it is a challenge to mine and analyze it deeply,extract valuable information efficiently,and serve for the actual *** to the features of these data,this paper uses artificial intelligence methods such as time series and support vector regression to establish a data mining network model for standard cost prediction through transfer *** experimental results show that the model in this paper obtains better prediction results on a small sample data set,which verifies the feasibility of the deep transfer *** with activity-based costing and the traditional prediction method,the average absolute error of the proposed method is reduced by 10%,which is effective and superior.

关键词： transfer learning LSTM support vector regression activity based costing State Grid

Multi-objective interval prediction of wind power based on conditional copula function

在线全文

学校读者我要写书评

暂无评论

Journal of Modern Power Systems and Clean Energy 2019年第4期7卷 802-812页

作者： Gang ZHANG Zhixuan LI Kaoshe ZHANG Lei ZHANG Xia HUA Yongqing WANG Institute of Water Resources and Hydro-electric Engineering Xi’an University of TechnologyXi’an 710048China State Grid Shaanxi Baoji electric Power company Baoji 721000China State Grid Gansu electric Power company Gansu Electric Power Research InstituteLanzhou 730050China State Grid Shaanxi electric Power company Shaanxi Electric Power Research InstituteXi’an 710054China

Interval prediction of wind power,which features the upper and lower limits of wind power at a given confidence level,plays a significant role in accurate prediction and stability of the power grid integrated with wind ***,the conventional methods of interval prediction are commonly based on a hypothetic probability distribution function,which neglects the correlations among various variables,leading to the decrease of prediction ***,we improve the multi-objective interval prediction based on the conditional copula function,through which we can fully utilize the correlations among variables to improve prediction accuracy without an assumed probability distribution *** use the multi-objective optimization method of nondominated sorting genetic algorithm-II(NSGA-II)to obtain the optimal solution *** particular best solution is weighted by the prediction interval average width(PIAW)and prediction interval coverage probability(PICP)to pick the optimized solution in practical ***,we apply the proposed method to three wind power plants in different cities in China as examples forvalidation and obtain higher prediction accuracy compared with other methods,i.e.,relevance vector machine(RVM),artificial neural network(ANN),and particle swarm optimization kernel extreme learning machine(PSO-KELM).These results demonstrate the superiority and practicability of this method in interval prediction of wind power.

关键词： Wind power prediction Interval prediction Conditional copula function Empirical distribution function Multi-objective optimization algorithm

A novel two-degree-of-freedom spherical ultrasonic motor using three travelling-wave type annular stators

在线全文

学校读者我要写书评

暂无评论

Journal of Central South University 2015年第4期22卷 1298-1306页

作者：王剑胡锡幸王班郭吉丰 College of electrical Engineering Zhejiang University Hangzhou Power Supply company of State Grid Zhejiang Electric Power Company

In order to promote the tolerance and controllability of the multi-degree-of-freedom(M-DOF) ultrasonic motor, a novel two-degree-of-freedom(2-DOF) spherical ultrasonic motor using three traveling-wave type annular stators was put forward. Firstly,the structure and working principle of this motor were introduced, especially a spiral spring as the preload applied component was designed for adaptive adjustment. Then, the friction drive model of 2-DOF spherical motor was built up from spatial geometric relation between three annular stators and the spherical rotor which was used to analyze the mechanical characteristics of the *** optimal control strategy for minimum norm solution of three stators' angular velocity was proposed, using Moore-Penrose generalized inverse matrix. Finally, a 2-DOF prototype was fabricated and tested, which ran stably and controllably. The maximum no-load velocity and stall torque are 92 r/min and 90 m N·m, respectively. The 2-DOF spherical ultrasonic motor has compact structure, easy assembly, good performance and stable operation.

关键词： two-degree-of-freedom ultrasonic motor spherical rotor friction drive model optimal control strategy

Low frequency oscillation characteristics of East China Power Grid after commissioning of Huai-Hu ultra-high voltage alternating current project

在线全文

学校读者我要写书评

暂无评论

Journal of Modern Power Systems and Clean Energy 2015年第3期3卷 332-340页

作者： Chao WANG Yang LV Hongyang HUANG Jing ZHANG Jihong LI Yingyi LI Weizhen SUN Yong CHANG State Grid Zhejiang electric Power company Hangzhou 310007China State Grid Jilin electric Power company Changchun 130000China State Grid Operation company Beijing 100052China

The low frequency oscillation characteristics of East China Power Grid after commissioning of the first ultra-high voltage alternating current(UHVAC)project-the Huai-Hu UHVAC project are *** low frequency oscillation cases occurred in East China Power Grid in the past few years are reviewed and *** on the analysis of the different typical operation modes,the main low frequency oscillation modes in East China Power Grid in the early stages of development of ultra-high voltage(UHV)are summarized,and the impacts of the significant power grid maintenance on low frequency oscillation characteristics are ***,the oscillation mode of UHV generators to East China Power Grid is researched,and the importance of the power system stabilizator(PSS)is ***,the comparative analysis between the time domain and the frequency domain is carried out,and the influences of the governing system on low frequency oscillation characteristics are ***,both the focus and the direction of low frequency oscillation research are presented.

关键词： Ultra-high voltage(UHV) Low frequency oscillation Forced oscillation Power system stabilizator(PSS) Governing system