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Journal of Hydrodynamics 2014年第2期26卷 277-290页

作者： TRIVEDI Chirag CERVANTES Michel J. GANDHI B.K. OLE DAHLHAUG G. division of Fluid and Experimental Mechanics Department of Engineering Sciences and Mathematics Lule? University of Technology Department of Mechanical and Industrial Engineering Indian Institute of Technology Water power Laboratory Department of Energy and Process Engineering Norwegian University of Science and Technology

Penetration of the power generated using wind and solar energy to electrical grid network causing several incidents of the grid tripping, power outage, and frequency drooping. This has increased restart （star-stop） cycles of the hydroelectric turbines significantly since grid connected hydroelectric turbines are widely used to manage critical conditions of the grid. Each cycle induces significant stresses due to unsteady pressure loading on the runner blades. The presented work investigates the pressure loading to a high head （ He = 377 m, De = 1.78 m） Francis turbine during start-stop. The measurements were carried out on a scaled model turbine （HM = 12.5 m, DM = 0.349 m）. Total four operating points were considered. At each operating point, three schemes of guide vanes opening and three schemes of guide vanes closing were investigated. The results show that total head variation is up to 9% during start-stop of the turbine. On the runner blade, the maximum pressure amplitudes are about 14 kPa and 16 kPa from the instantaneous mean value of 121 kPa during rapid start-up and shutdown, respectively, which are about 1.5 times larger than that of the slow start-up and shutdown. Moreover, the maximum pressure fluctuations are given at the blade trailing edge.

关键词： Francis turbine pressure fluctuations start-up shutdown transient

Design of Capacitor Bank in Parallel to Photovoltaic power Plant

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Journal of Energy and power Engineering 2014年第5期8卷 939-947页

作者： A. Kalyuzhny B. Reshef G.Yehuda G.David P. Koulbekov T. Day Planning Development & Technology Division Israel Electric Company Haifa 31000 Israel Eaton's Cooper power Systems business Auburn CA 95602 USA

The purpose of the paper is to develop a solution for application of PV （photovoltaic） generators in MV （medium voltage） distribution system without unacceptable voltage changes due to drops of PV power output. The proposed solution includes operation of PV with predetermined leading power factor and addition of a capacitor bank in parallel to PV plant in order to compensate the reactive power absorbed by the PV inverters. The analytical expression of required power factor angle is derived. Adding a capacitor bank in parallel to PV power plant may pose a problem because of space limitations. The dimensions and cost of small MV capacitor banks depend significantly on the capacitor bank protection against internal faults. Application of the developed negative-sequence current difference method for the unbalance protection of the capacitor banks enables to achieve a compact and cost-reduced design of the banks connected in parallel to PV power plants. A real-world example of operation of the PV plant in parallel to the capacitor bank with the novel protection scheme is described.

关键词： Photovoltaic power plant power quality capacitor bank unbalance protection.

Energy Storage in High Variable Renewable Energy Penetration power Systems:Technologies and Applications

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CSEE Journal of power and Energy Systems 2023年第6期9卷 2099-2108页

作者： Huan Zhu Hu Li Guojing Liu Yi Ge Jing Shi Hai Li Ning Zhang State Grid Jiangsu Electric power Co. LtdNanjingChina Economic Research Institute of State Grid Jiangsu Electric power Company NanjingChina the State Key Laboratory of power Systems Department of Electrical EngineeringTsinghua UniversityBeijing 100084China

Integrating variable renewable energy is one of the most effective ways to achieve a low-carbon energy *** high penetration of variable renewable energy,such as wind power and photovoltaic,increases the challenge of balancing the power *** storage technology is regarded as one of the key technologies for balancing the intermittency of variable renewable energy to achieve high *** study reviews the energy storage technology that can accommodate the high penetration of variable renewable *** basic energy storage technologies that can accommodate time-scale variation are reviewed *** role of energy storage in the generation,transmission,distribution,and consumption for the high variable renewable energy penetration system is then *** supporting energy storage policies in the United States,the United Kingdom and China are *** suggestions are proposed from the perspectives of technology,business and *** paper provides guidelines for planning energy storage to enable a high variable renewable energy penetration power system.

关键词： Application scenarios energy storage penetration renewable energy supporting policies

Computational study of wing deformation and sting interference effects with the CAE-AVM test case

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Chinese Journal of Aeronautics 2018年第10期31卷 1954-1961页

作者： Innokentiy KURSAKOV Egor KAZHAN Roy GEBBINK Central Aerohydrodynamic Institute Named After Professor N.E.Zhukovsky(TsAGI) Zhukovskiy 140180Russia German-Dutch wind Tunnels(DNW) Marknesse 8316 PRThe Netherlands

A modern transonic computational fluid dynamics test case is described in this paper,which is the Aerodynamic Validation Model（AVM） from the Chinese Aeronautical Establishment（CAE）. The CAE-AVM is a representation of a modern transonic business jet aircraft with a design Mach number of 0.85. Numerical simulations for the AVM are conducted for two geometries： one baseline geometry, and one geometry that includes the applied model support system of the wind tunnel as well as the deformed wing shape that occurred during wind tunnel testing. The combined influence of wing deformation and model support interference on local and integral aerodynamic features is presented. Comparisons between CFD and experimental results are made; reasons of discrepancy between results from considered cases are analyzed.

关键词： Aerodynamic validation model CFD Sting interference Transonic test Wing deformation

Chimney Effect Assessment of the Double-skin Facade

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湖南大学学报（自然科学版） 2009年第S1期36卷 146-150页

作者： QIU Zhong-zhu1,LI Peng2,CHOW Tin-tai3,REN Jian-xing1,WANG Wen-huan1(1.School of Energy & Environment Engineering,Shanghai University of Electric power,Shanghai 20090,China 2.School of Mechanical Engineering,Tongji University,Shanghai 200092,China 3.division of Building Science & Technology,City University of Hong Kong,Hong Kong SAR,China) School of Energy and Environment Engineering Shanghai University of Electric Power Shanghai 200090 China School of Mechanical Engineering Tongji University Shanghai 200092 China division of Building Science and Technology City University of Hong Kong Hong Kong Hong Kong

The mathematic model of heat transfer through ventilated double glazing was verified with the measured data,which were from a test chamber equipped with glass face temperature,solar radiation,ambient temperature,and wind speed measurement *** the model validation,the double-skin facade assessment was carried out through simulation with ESP-r software integrating thermal simulation and air low net work *** air flow situation in the air gap was analyzed on the basis of the hourly air velocity simulation data within typical winter week,summer week,spring week and autumn *** differences of chimney effect in different seasons were discussed,and the thermal loads resulted from the ventilated and unventilated double skin facade were presented.

关键词： chimney effect assessment double-skin facade

基于智能电网构建的欧洲可再生能源电力系统现状和前景展望(英文)

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电力系统自动化 2011年第22期35卷 12-17页

作者： Yi DING Jacob OSTERGAARD Poul Ejnar SORENSEN Peter MEIBOM Qiuwei WU Center for Electric Technology Department of Electrical Engineering Technical University of Denmark Kgs. Lyngby 2800 Denmark Riso DTU wind Energy division Technical University of Denmark Roskilde 4000 Denmark Riso DTU Intelligent Energy Systems division Technical University of Denmark Roskilde 4000 Denmark

可再生能源在欧盟未来的能源框架中扮演着重要角色。到2020年,在欧盟总的能源消耗量中,预期20%将来自可再生能源,并且能效将提高20%。智能电网将是未来电力系统接纳大规模可再生能源发电并网的基石。文中介绍了欧洲的可再生能源开发现... 详细信息

可再生能源在欧盟未来的能源框架中扮演着重要角色。到2020年,在欧盟总的能源消耗量中,预期20%将来自可再生能源,并且能效将提高20%。智能电网将是未来电力系统接纳大规模可再生能源发电并网的基石。文中介绍了欧洲的可再生能源开发现状和规划以及能源政策,并讨论了欧盟在智能电网相关技术方面的研发进展。丹麦是欧盟国家中可再生能源使用和相关关键技术研发的领跑者,文中重点以其为例进行介绍和阐述。

关键词：可再生能源风力发电智能电网欧盟丹麦

Analysis of value of flexibility in Japan’s power system with increased VRE

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Clean Energy 2018年第1期2卷 37-44页

作者： Sumie Nakayama Hitoshi Azuma Suguru Fukutome Kazuhiko Ogimoto J-power/Electric power Development Co. Ltd.6-15-1GinzaChuo-kuTokyo 104-8165Japan JP business Service Corporation 2-2-18FukagawaKoto-kuTokyo 135-8451Japan Institute of Industrial Science Collaborative Research Center for Energy EngineeringThe University of Tokyo4-6-1KomabaMeguro-kuTokyo153-8585Japan

The growth of renewable energy has accelerated globally toward a low-carbon economy since the Paris Agreement entered into force in *** a result of the increase of variable renewable energy(VRE),namely solar PV and wind,power systems require more flexibility from conventional power plants with less power generation to regulate increased *** are sources of flexibility other than conventional power plants,including enhanced power networks,storage capacity and demand *** maximize economic utilization of VRE power generation,it is necessary to use the flexibility potential from all these *** Japan,the share of VRE has increased since the introduction of a feed-in tariff(FIT)and,in parallel,power market reform is *** has a unique power system of nine grids connected like a fish bone,making the uptake of an increasing share of VRE *** paper assesses the value of flexibility by source in Japan’s power system in *** analysis of different VRE scenarios is undertaken based on a newly developed production cost *** result of the simulation shows the quantitative impact of each source of flexibility to the generation cost and VRE curtailment and demonstrates the mechanism by which flexibility works to impact VRE curtailment.

关键词： component power demand and supply renewable energy flexibility Japan’s power system produc-tion cost model analysis

Development of Vehicle-to-Grid Systemto Regulate the System Parameters of Microgrid

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Energy Engineering 2022年第4期119卷 1261-1298页

作者： Om PrakashMahela Baseem Khan Rupendra Kumar Pachauri power System Planning division Rajasthan Rajya Vidyut Prasaran NigamLtd.Vidyut BhawanJapurIndia Department of Electrical and Computer Engineering Hawassa UniversityHawassaEthiopia Electrical Engineering Department School of EngineeringUniversity of Petroleum and Energy StudiesDehradunIndia

This paper proposes a vehicle-to-grid(V2G)system interfaced with a microgrid that is effective at regulating frequency on a microgrid over a 24-h cycle.A microgrid is designed and divided into four *** first component is a diesel generator,which is used to act as the base power *** second component consists of renewable energy(RE)power plants,which include solar photovoltaic(PV)and wind *** third component is a V2G *** last component is the load connected to the microgrid.A microgrid is designed to be of sufficient size to represent a community of one thousand households during the day period of low consumption in the spring or fall seasons.A hundred electric vehicles(EVs)are modeled as base models to realize a 1:10 ratio for cars to households,which indicates a possible scenario in the near *** analysis of the active power,reactive power,voltage,frequency,and current is carried *** is established that the proposed design of the V2G andmicrogrid effectivelymaintains systemparameters such as frequency and voltage within permissible limits with an error of less than 1%.Further,transient deviations in these parameters are limited to within 5%.A microgrid with V2G devices regulates the system frequency by mitigating load demand through coordinated control of conventional generation,solar PV plant generation,wind plant generation,power exchange with the microgrid network,and electric *** proposed microgrid and V2G are efficient for energy management and mitigation of intermittency and variability of RE power with improved *** in system parameters have been investigated by changing the operating scenario,and it has been determined that the error is limited to less than 5%.The study is effectively realized in the MATLAB/Simulink environment.

关键词： Microgrid electric vehicles vehicle-to-grid renewable energy PV wind

基于频域的风电场功率波动仿真(一)模型及分析技术

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电力系统自动化 2011年第4期35卷 65-69页

作者：林今孙元章 P.SФRENSEN 李国杰程林黎雄电力系统国家重点实验室清华大学电机系北京市100084 wind Energy division at Riso DTU Technical University of DenmarkRoskilde 4000丹麦

随着国内风电装机容量的不断攀升,风电场的随机功率波动将显著影响电力系统的安全可靠运行。现有研究多从时域或统计的角度出发,研究功率波动对电力系统的影响。然而,由于时域或统计的方法无法完整描述功率波动产生的物理机理,其评估结... 详细信息

随着国内风电装机容量的不断攀升,风电场的随机功率波动将显著影响电力系统的安全可靠运行。现有研究多从时域或统计的角度出发,研究功率波动对电力系统的影响。然而,由于时域或统计的方法无法完整描述功率波动产生的物理机理,其评估结果偏差较大。为了克服以上问题,文中从频域的角度出发,以风速的谱密度函数为基础,结合风电机组的频域模型及风电场天气、地理位置等信息,研究大型风电场随机功率波动的频域特性。相对于传统的时域或统计方法,基于频域的方法物理意义更为清晰,能够针对大型风电场功率波动形成的每一个过程均建立较为准确且实用的模型。通过对比某风电场的实测与仿真数据,验证了所提出方法的正确性和有效性。

关键词：风电场功率波动频域功率谱密度

Self-interstitials generated on silicon bulk surface

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Progress in Natural Science:Materials International 2011年第1期21卷 17-20页

作者： Yukihiro KATO Ryoji FUKUDA Yuta TAKENO Toshitada SHIMOZAKI Takahisa OKINO Department of Design Engineering Semiconductor Business DivisionMitsumi Electric Co.LtdAtugi 243-0004Japan Department of Architecture and Mechatronics Faculty of EngineeringOita UniversityOita 870-1192Japan Department of Materials and Technology Kyushu Institute of TechnologyKitakyushu 804Japan

The self-interstitial atoms in silicon generated by the bulk surface oxidation diffuse into the bulk inside and affect the phenomena such as the diffusions and the stacking *** generation rate of self-interstitials(Rgen) depends on theωpower of the oxidation film growth rate dX0/*** physical quantityωis important to understand the material science relevant to self-interstitials in the silicon ***,the conclusiveωvalue is not reported,although variousωvalues to control the generation rate have been *** the present study,the chemical reaction equation is analytically solved,and using the result,the oxidation stacking fault radius(r) is analytically expressed against the oxidation time(t).Comparing the obtained relation of r=r(t) with the experimental results of the stacking faults,the analytical expression of co is determined and the physical meaning ofωis ***,the temperature dependence ofωis also numerically determined.

关键词： silicon self-interstitial vacancy oxide impurity diffusion stacking fault