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Chinese Physics B 2013年第8期22卷 620-626页

作者：伍展文李洁黎松林郑东宁 Beijing National Laboratory for Condensed Matter Physics & Institute of Physics Chinese Academy of Sciences Institute of Testing and Research Zhongshan Power Supply Bureau Guangdong Power Grid Corporation

Epitaxial La2/3Cal/3MnO3 thin films grown on LaA103 （001） substrates were irradiated with low-energy 120-keV H＋ ions over doses ranging from 1012 ions/cm2 to 1017 ions/cm2. The irradiation suppresses the intrinsic insulator-metal （I-M） transition temperature and increases the resistance by reducing the crystallographic symmetry of the films. No irradiation-induced columnar defects were observed in any of the samples. The specific film irradiated at a critical dose around 8 x 1015 ions/cm2 is in a threshold state of the electric insulator where the I-M transition is absent. In an external field of 4 T or higher, the I-M transition is restored and thus an enormous magnetoresistance is observed, while a negative temperature coefficient resumes as the temperature is reduced further. Magnetic relaxation behavior is confirmed in this and other heavily irradiated samples. The results are interpreted in terms of the displacement of oxygen atoms provoked by ion irradiation and the resulting magnetic glassy state, which can be driven into a phase coexistence of metallic ferromagnetic droplets and the insulating glass matrix in a magnetic field.

关键词： manganite ion irradiation magnetoresistance

Stochastic Flexibility Evaluation for Virtual power Plants by Aggregating Distributed Energy Resources

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CSEE Journal of power and Energy Systems 2024年第3期10卷 988-999页

作者： Siyuan Wang Wenchuan Wu Qizhan Chen Junjie Yu Peng Wang Department of Electrical Engineering Tsinghua UniversityBeijing 100084China zhongshan power supply bureau of the guangdong power grid corporation Zhongshan 528400China Beijing Qingda Gaoke System Control Company Beijing 102208China CSEE IEEE

To manage a large amount of flexible distributed energy resources(DERs)in the distribution networks,the virtual power plant(VPP)is introduced into the *** VPP can optimally dispatch these resources in a cluster manner and provide flexibility for the power system operation as a *** existing studies formulate the equivalent power flexibility of the aggregating DERs as deterministic optimization models without considering their *** this paper,we introduce the stochastic power flexibility range(PFR)and timecoupling flexibility(TCF)to describe the power flexibility of *** this model,both operational constraints and the randomness of the DERs’output are incorporated,and a combined model and data-driven solution is proposed to obtain the stochastic PFR,TCF,and cost function of *** aggregating model can be easily incorporated into the optimization model for the power system operator or market bidding,considering ***,a numerical test is *** results show that the proposed model not only has higher computational efficiency than the scenario-based methods but also achieves more economic benefits.

关键词： Chance constrained optimization combined model and data-driven stochastic power flexibility virtual power plant

Statistical characteristics and mechanism analysis of adhered particle on surface under strong electric field

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Particuology 2019年第2期17卷 110-122页

作者： Yunpeng Jiang Lee Li Ming Lu Rumeng Wang Yiwen Jiang Shanfeng Liu Chao Su State Key Laboratory of Advanced Electromagnetic Engineering and Technology Huazhong University of Science & Technology Wuhan 430074 China State grid Henan Electric power Research Institute Zhengzhou 450052 China Qingyuan power supply bureau of guangdong power grid corporation Guangdong 511515 China

Insulators on high-voltage Uansmission lines are almost the only man-made structures on the Earth's surface intended for long-term operation under strong electric fields. After samples of natural contaminant particles were collected from insulator surfaces in China, it was found that the particle diameter distribution (PDD) was mainly concentrated in the 5-50 μm range. To analyze the statistical characteristics of these particles, this work studies the physical processes of particle collision and adhesion using the theories of hydrodynamics and collision dynamics. The physical model considers coupling of the fluid field and the electric field, introduces an adhesion criterion, and establishes a particle and surface collision model. The effects of relative humidity, wind speed, aerodynamic shape, electric field type, and electric field strength on particle adhesion were analyzed. The results show that the relative humidity and wind speed have very significant effects and the influences of the electric field type and the electric field strength are obvious, but the in fluence of the aerodynamic shape is relatively weak. The simulation results support the statistical characteristics determined in this work. The physical model established here provides reference values for study of the adhesion characteristics of particles on surfaces under electric fields.

关键词： Contaminant particle Collision Adhesion Particle diameter Simulation analysis

Data-driven Inverter-based Volt/VAr Control for Partially Observable Distribution Networks

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CSEE Journal of power and Energy Systems 2023年第2期9卷 548-560页

作者： Tong Xu Wenchuan Wu Yiwen Hong Junjie Yu Fazhong Zhang Southwest Electric power Design Institute Co. Ltd.of China Power Engineering Consulting GroupChengduSichuan 610021China Tsinghua University Beijing 100084China Department of Electrical Engineering State Key Laboratory of Power SystemsTsinghua UniversityBeijing 100084China guangdong power grid zhongshan power supply bureau Zhongshan 528400China

For active distribution networks(ADNs)integrated with massive inverter-based energy resources,it is impractical to maintain the accurate model and deploy measurements at all nodes due to the large-scale of ***,current models of ADNs usually involve significant errors or even unknown ***,ADNs are usually partially observable since only a few measurements are available at pilot nodes or nodes with significant *** provide a practical Volt/Var control(VVC)strategy for such networks,a data-driven VVC method is proposed in this ***,the system response policy,approximating the relationship between the control variables and states of monitoring nodes,is estimated by a recursive regression closed-form ***,based on real-time measurements and the newly updated system response policy,a VVC strategy with convergence guarantee is *** the recursive regression solution is embedded in the control stage,a data-driven closedloop VVC framework is *** effectiveness of the proposed method is validated in an unbalanced distribution system considering nonlinear loads,where not only the rapid and self-adaptive voltage regulation is realized,but also systemwide optimization is achieved.

关键词： Data-driven distribution networks partial observation Volt/VAr control

Data-Driven Modeling for Wind Turbine Blade Loads Based on Deep Neural Network

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Energy Engineering 2024年第12期121卷 3825-3841页

作者： Jianyong Ao Yanping Li Shengqing Hu Songyu Gao Qi Yao Yangjiang power supply bureau Guangdong Power GridYangjiang529500China Energy and Electricity Research Center Jinan UniversityZhuhai519070China

Blades are essential components of wind *** their fatigue loads during operation helps to extend their lifespan,but it is difficult to quickly and accurately calculate the fatigue loads of *** solve this problem,this paper innovatively designs a data-driven blade load modeling method based on a deep learning framework through mechanism analysis,feature selection,and model *** the mechanism analysis part,the generation mechanism of blade loads and the load theoretical calculationmethod based on material damage theory are analyzed,and four measurable operating state parameters related to blade loads are screened;in the feature extraction part,15 characteristic indicators of each screened parameter are extracted in the time and frequency domain,and feature selection is completed through correlation analysis with blade loads to determine the input parameters of data-driven modeling;in the model construction part,a deep neural network based on feedforward and feedback propagation is designed to construct the nonlinear coupling relationship between the unit operating parameter characteristics and blade *** results show that the proposed method mines the wind turbine operating state characteristics highly correlated with the blade load,such as the standard deviation of wind *** model built using these characteristics has reasonable calculation and fitting capabilities for the blade load and shows a better fitting level for untrained out-of-sample data than the traditional *** on the mean absolute percentage error calculation,the modeling accuracy of the two blade loads can reach more than 90%and 80%,respectively,providing a good foundation for the subsequent optimization control to suppress the blade load.

关键词： Wind turbine blade fatigue load modeling deep neural network

Capacity Optimization Configuration of Hydrogen Production System for Offshore Surplus Wind power

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Energy Engineering 2023年第12期120卷 2803-2818页

作者： Yanshan Lu Binbin He Jun Jiang Ruixiao Lin Xinzhen Zhang Zaimin Yang Zhi Rao Wenchuan Meng Siyang Sun Guangzhou power supply bureau Guangdong Grid CorporationGuangzhou510620China Sichuan Energy Internet Research Institute Tsinghua UniversityChengdu610042China Energy Development Research Institute Co. Ltd.China Southern Power GridGuangzhou510530China

To solve the problem of residual wind power in offshore wind farms,a hydrogen production system with a reasonable capacity was configured to enhance the local load of wind farms and promote the local consumption of residual wind *** studying the mathematical model of wind power output and calculating surplus wind power,as well as considering the hydrogen production/storage characteristics of the electrolyzer and hydrogen storage tank,an innovative capacity optimization allocation model was *** objective of the model was to achieve the lowest total net present value over the entire life *** model took into account the cost-benefit breakdown of equipment end-of-life cost,replacement cost,residual value gain,wind abandonment penalty,hydrogen transportation,and environmental *** MATLAB-based platform invoked the CPLEX commercial solver to solve the *** with the analysis of the annual average wind speed data from an offshore wind farm in guangdong Province,the optimal capacity configuration results and the actual operation of the hydrogen production system were *** the calculation scenario,this hydrogen production system could consume 3,800 MWh of residual electricity from offshore wind power each *** could achieve complete consumption of residual electricity from wind power without incurring the penalty cost of wind ***,it could produce 66,500 kg of green hydrogen from wind power,resulting in hydrogen sales revenue of 3.63 million *** would also reduce pollutant emissions from coal-based hydrogen production by 1.5 tons and realize an environmental value of 4.83 million *** annual net operating income exceeded 6 million RMB and the whole life cycle NPV income exceeded 50 million *** results verified the feasibility and rationality of the established capacity optimization allocation *** model could help advance power system planning and operation research and assist offshore wind farm

关键词： Surplus wind power offshore wind power hydrogen generation capacity optimization configuration total net present cost

A robust optimization model for demand response management with source-grid-load collaboration to consume wind-power

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Global Energy Interconnection 2023年第6期6卷 738-750页

作者： Xiangfeng Zhou Chunyuan Cai Yongjian Li Jiekang Wu Yaoguo Zhan Yehua Sun zhongshan power supply bureau of guangdong power grid Co. Ltd.Zhongshan 528401GuangdongP.R.China School of Automation Guangdong University of TechnologyGuangzhou 510006GuangdongP.R.China

To accommodate wind power as safely as possible and deal with the uncertainties of the output power of winddriven generators,a min-max-min two-stage robust optimization model is presented,considering the unit commitment,source-network load collaboration,and control of the load demand *** the constraint functions are linearized,the original problem is decomposed into the main problem and subproblem as a matrix using the strong dual *** minimum-maximum of the original problem was continuously maximized using the iterative method,and the optimal solution was finally *** constraint conditions expressed by the matrix may reduce the calculation time,and the upper and lower boundaries of the original problem may rapidly *** results of the example show that the injected nodes of the wind farms in the power grid should be selected appropriately;otherwise,it is easy to cause excessive accommodation of wind power at some nodes,leading to a surge in reserve costs and the load demand response is continuously optimized to reduce the inverse peak regulation characteristics of wind ***,the most economical optimization scheme for the worst scenario of the output power of the generators is obtained,which proves the economy and reliability of the two-stage robust optimization method.

关键词： Renewable power system Optimal dispatching Wind-power consumption Source-grid-load collaboration Load demand response Two-stage robust optimization model

Transmission Tower Stress Analysis and Online Monitoring Scheme

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Transmission Tower Stress Analysis and Online Monitoring Sch...

Research on Intelligent Concentrator Based on Edge Computing Technology

作者： Tuan-jie GAN Xin YAN Xi YANG Yi-nan GENG Xin TANG Ya MOU Zhan-qing YU Jiangmen power supply bureau of guangdong power grid Co China Southern Power Grid Corporation Key Lab of power Systems Department of Electrical EngineeringTsinghua University

So far,the theoretical study of the transmission tower line is not enough for the research and analysis of the transmission line under the wire icing and strong wind *** understanding of the disaster load mechanism,structural analysis method and vibration control is still insufficient,resulting in the accidents of broken towers caused by ice coating,wind load and geological disasters still occur frequently,which is one of the main hazards of safe operation of power *** of this paper,the failure mechanism of transmission towers in various environments is studied in ***,the mechanical characteristics of towers under environmental load are analyzed by finite element simulation ***,an online monitoring method which is based on the mechanical characteristics of transmission tower,is proposed to detect the stress state and determine if there is a fault will occur or has *** these circumstances,the force of transmission towers will be known in real time,and power grid disaster can be prevented in advance.

关键词： Transmission tower Failure mechanism Mechanical properties Online monitoring

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Research on Intelligent Concentrator Based on Edge Computing...

Design and application of intelligent concentrator based on Internet of things

第32届中国控制与决策会议

作者： Xiaojiang Chen Tinghui Lu Jijun Zeng Zheheng Liang Fengchan Guo Jin Li guangdong power grid corporation Information Center Jiangmen power supply bureau Guangdong Power Grid Co.Ltd. School of Electrical Engineering and Automation Hefei University of Technology

At present,the power metering equipment used at the grass-level sends the collected data to the intelligent concentrator,and then it is stored and forwarded to the master station through the concentrator,and finally the data is processed through cloud computing of the main *** the concentrator currently used cannot process data,it brings great trouble to the system master *** at this situation,this paper proposes the design method of concentrator based on edge computing ***,the edge computing technology is introduced briefly,and then the problems of current concentrator are improved,and a new generation of intelligent concentrator is ***,the system function is designed as a whole,and the hardware architecture and communication scheme are *** system can not only solve the problem of data processing,but also has real-time monitoring and secure and reliable communication.

关键词： Intelligent concentrator Data processing Edge calculation,Real-time monitoring Secure communication

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Design and application of intelligent concentrator based on ...