检索结果-南通市图书馆

Effect of TiO_(2)coating on the surface condition and corona characteristics of positive DC conductors with particle matters

在线全文

学校读者我要写书评

暂无评论

High Voltage 2022年第1期7卷 147-157页

作者： Pei Xu Yanxiang Ma Jie Zhu Luxing Zhao Boyang Shen Xingming Bian State Key Laboratory of Alternate Electrical power System with Renewable Energy Sources North China Electric Power UniversityBeijingChina Shijingshan power supply company State Grid Beijing Electric Power Supply CompanyBeijingChina Yangzhou power supply company State Grid Jiangsu Electric Power Supply CompanyYangzhouChina High Voltage Research Department China Electric Power Research InstituteBeijingChina Electrical Engineering Division University of CambridgeCambridgeUK

Persistent severe smog and dust weather exists in many regions of *** accu-mulate on the surface of high‐voltage transmission lines,which affects the surface morphology of the transmission line and induces corona *** work mainly studies the influence of electric field and photocatalysis on the corona characteristics of transmission *** this work,plasma spraying is used to prepare a dense,smooth and excellent photocatalytic TiO_(2)coating on the surface of transmission *** electron microscope and a white light interference profilometer is used to study the surface condition of the *** variation in the surface condition of the samples is observed under different fouling,light time and electric field *** corona characteristics of power transmission lines under different surface conditions are *** results show that light and applied electric field promote the photocatalytic effect of TiO_(2),which helps to decompose the contamination on the surface of power transmission wires and thus reduce the corona discharge of transmission *** increase in corona inception voltage reduces the corona current pulse repetition rate and the ion current density during corona discharge.

关键词： discharge. coating surface

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

在线全文

维普期刊数据库

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

Mode for reducing wind curtailment based on battery transportation

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 2018年第6期6卷 1158-1171页

作者： Zhanlong ZHANG Daojun MEI Han JIANG Guohua LIU Hongpeng HE Yue CHEN State Key Laboratory of power Transmission Equipment and System Security and New Technology Chongqing University Quzhou power supply company State Grid Electric Power Company

Renewable energy sources, such as wind and solar, face several obstacles, including curtailment, where the generated energy exceeds local demand and production must be reduced because of limited transmission ***, consumer demand for large-capacity batteries is expanding given the recent rapid development of electric vehicles(EVs) and plug-in hybrid EVs. A batterycharging mode, in which discharged batteries are transported from battery exchange stations in high-load areas to wind farms, is proposed to alleviate curtailment. In this study, batteries store otherwise curtailed energy and smooth the wind power output simultaneously. The structure of the battery-charging device is discussed, and the concept of a battery-charging container is proposed. The control principle of the battery-charging management unit is presented with a simulation model constructed in the PSCAD/EMTDC environment. A case study is simulated,and the feasibility of the mode is analyzed considering the levelized cost and energy losses. Simulation results show that this mode is a feasible solution to alleviating wind curtailment and providing fresh impetus for developing EV battery exchanges.

关键词： Wind curtailment Battery-charging container Transportation power smoothing

Effects of ambient humidity and thermal aging on properties of Nomex insulation in mining dry‐type transformer

在线全文

学校读者我要写书评

暂无评论

High Voltage 2021年第1期6卷 71-81页

作者： Lu Li Jiancheng Song Zhipeng Lei Ailiang Kang Zhengyu Wang Rujia Men Yun Ma Shanxi Key Laboratory of Mining Electrical Equipment and Intelligent Control College of Electrical and Power EngineeringTaiyuan University of TechnologyTaiyuan ShanxiChina Zhengzhou power supply company State Grid Henan Electric Power CompanyZhengzhou HenanChina Jinzhong power supply company State Grid Shanxi Electric Power CompanyJinzhong ShanxiChina

Temperature and humidity are the main factors that cause the decomposition of Nomex paper widely used as turn‐to‐turn insulation material of mining dry‐type transformers. In this study, for understanding the effect of ambient humidity and thermal aging on the properties of Nomex paper, specimens with the initial moisture content of 7% were aged in the oven for 168, 504, 672 h at 180°C, respectively. After thermal aging, corona discharge experiments of unaged and aged specimens with different aging degrees were carried out at different relative humidity (RH) levels from 10 to 70%. The characteristic parameters of corona discharge, such as the average discharge amplitude and the number of discharges, were measured. Then, the surface conductivity and the surface potential decay rate were measured. The morphology and attenuated total internal reflectance Fourier transform infrared spectroscopy were also analysed for explaining the difference of properties be-tween unaged and aged specimens. The experiment results indicate that the average discharge amplitude decreases with the increase of RH or the deepening of the aging degree of specimens, but the number of discharges shows the reversal tendency. The changes in the physical structure and chemical composition, which is induced by the hydrolysis reaction of Nomex paper, accelerate the surface potential decay and increase the surface conductivity.

关键词： aging thermal humidity

Effects of nanofiller and voltage stabilizer on partial discharge resistance of polypropylene/elastomer blends:A comparison study

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

High Voltage 2023年第2期8卷 251-261页

作者： Yu Gao Jing Li Xuri Xu Jinjing Peng Tao Han Boxue Du School of Electrical and Information Engineering Tianjin UniversityTianjinChina State Grid Yancheng power supply company YanchengChina Guangzhou Panyu power supply Bureau Guangzhou Power Grid CorporationGuangzhouChina

This paper reports on the individual and synergistic influence mechanisms of nano-silica(SiO_(2))and voltage stabilizers on partial discharge(PD)resistance of polypropylene blended with ethylene-octene copolymer *** SiO_(2)nanoparticles and three types of voltage stabilizers,that is,benzoin,4,40-dimethoxybenzil,and 3-aminobenzoic acid are selected as fillers to prepare *** is initiated in a rod-to-plane electrode system with an alternating current voltage of 5 *** characteristics are captured with multi-sensors,and the erosion profile of the test sample is measured using a three-dimensional(3D)optical *** trap distribution is extracted with isothermal surface potential decay measurement to assist the analysis of PD eroding *** transform infrared spectrum,scanning electron microscopy,X-ray diffraction spectrum,and differential scanning calorimetry analysis are performed to reveal the change in material structures caused by the *** results indicate that the PD resistance of the blend can be improved by the addition of nano-SiO_(2)and voltage stabilizers individually and *** PD resistance of PO is increased by 71.2%at most in the sample with 3 wt%nano-SiO_(2)*** sample filled with SiO_(2)exhibits better PD resistance than that with the voltage stabilizer or co-added,which should be ascribed to the introduction of deep traps,the formation of the packaged layer,the suppression of oxygen diffusion of the nanofillers,and the good compatibility between additives and the polymer matrix.

关键词： polypropylene synergistic blends

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

在线全文

维普期刊数据库

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

Generation dispatch method based on maximum entropy principle for power systems with high penetration of wind power

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 2018年第6期6卷 1213-1222页

作者： Qiaoyan BIAN Yutao QIU Wenlian WU Huanhai XIN Xuhua FU Hangzhou power supply company of State Grid Zhejiang Electric power company State Grid Zhejiang Electric power company College of Electrical Engineering Zhejiang University Zhejiang power Economic Research Institute of State Grid

This paper proposes a generation dispatch model based on the maximum entropy principle. The objective is to find an optimal generation dispatch strategy that minimizes the generation cost and satisfies the security constraints of power systems, while taking into account the uncertainty of wind power. Since in many situations, only partial information of the probabilistic variables can be obtained, the maximum entropy principle is introduced to find the most likely realized probability distributions of the power flow, thus providing an accurate probabilistic circumstance to solve the generation dispatch model. The proposed method is tested on the IEEE 39-bus system, and is compared with the methodologies based on Monte Carlo simulation and Gram-Charlier expansions.

关键词： Generation dispatch Strategy Maximum entropy Probability distribution Cumulant

Using Grey Target Theory for power Quality Evaluation Based on power Quality Monitoring Data

在线全文

学校读者我要写书评

暂无评论

Energy Engineering 2022年第1期119卷 359-369页

作者： Qiang Yu Xiankai Chen Xiaoyue Li Chaoqun Zhou Zhichao Li State Grid Qingdao power supply company Qingdao266000China

Smart grid puts forward higher requirements for power *** quality evaluation can provide a decision-making basis for quality *** on power quality monitoring data,a grey target method is proposed for power quality *** grey target is composed of power quality evaluation standard and power quality monitoring data to be *** with the characteristics of each power quality evaluation index,the target center of the whole grey target system is ***,the power quality monitoring data to be evaluated and the power quality standard mode are compared and analyzed to construct the power quality grey correlation difference information ***,the target center coefficient and target degree of power quality are calculated to realize the comprehensive evaluation of power quality,and the evaluation grade of power quality monitoring data to be evaluated is *** with the evaluation results of the existing literature,the effectiveness of the proposed method is verified,which shows that grey target theory is reasonable in the comprehensive evaluation of power quality.

关键词： Smart grid power quality evaluation grey target theory monitoring data

Research on Online Monitoring Methods on SF_(6) Circuit Breakers

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

高压电器 2019年第3期55卷 1-7,14页

作者： CHENG Tingting GAO Wensheng ZHAO Yuming Department of Electrical Engineering Tsinghua University Shenzhen power supply company

To promote the accuracy and application of arcing time measurement for SF_6 circuit breaker in substation,five measurement methods are investigated by two cases experimentally. First,the test results of the five methods for a circuit breaker in different stages of wear and a circuit breaker with a component failure were presented. Then,the time error is analyzed by ***,the advantage and disadvantage of these methods are discussed.

关键词： circuit breaker high voltage circuit breaker arcing time arc duration online monitoring wavelet analysis