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Dynamic simulation and optimization approach to construction diversion of hydraulic and hydroelectric projects

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Science China(Technological Sciences) 2009年第7期52卷 1990-1998页

作者： ZHONG DengHua LI MingChao HUANG Wei LIU Yong Department of Hydraulic and hydroelectric Engineering School of Civil EngineeringTianjin UniversityTianjin 300072China

To solve the engineering and scientific problems in construction diversion and its simulation analysis, a complete scheme is presented. Firstly, the complex constraint relationship was analyzed among main buildings, diversion buildings and flow control. Secondly, the time-space relationship model of construction diversion system and the general block diagram-oriented simulation model of diversion process were set up. Then, the corresponding numerical simulation method and 3D dynamic visual simulation method were put forward. Further, the simulation and optimization platform of construction diversion control process was developed, integrated with simulation modeling, computation and visualization. Finally, these methods were applied to a practical project successfully, showing that the modeling process is convenient, the computation and the visual analysis can be coupled effectively, and the results conform to practical state. They provide new theoretical principles and technical measures for analyzing the control problems encountered in construction diversion of hydraulic and hydroelectric engineering under complex conditions.

关键词： construction diversion dynamic simulation optimization analysis block diagram hydraulic and hydroelectric project

3D integrated modeling approach to geo-engineering objects of hydraulic and hydroelectric projects

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Science China(Technological Sciences) 2007年第3期50卷 329-342页

作者： ZHONG DengHua LI MingChao LIU Jie Department of Hydraulic and hydroelectric Engineering School of Civil EngineeringTianjin UniversityTianjin 300072China

Aiming at 3D modeling and analyzing problems of hydraulic and hydroelectric en-gineering geology,a complete scheme of solution is presented. The first basis was NURBS-TIN-BRep hybrid data structure. Then,according to the classified thought of the object-oriented technique,the different 3D models of geological and engi-neering objects were realized based on the data structure,including terrain class,strata class,fault class,and limit class;and the modeling mechanism was alterna-tive. Finally,the 3D integrated model was established by Boolean operations be-tween 3D geological objects and engineering objects. On the basis of the 3D model,a series of applied analysis techniques of hydraulic and hydroelectric engineering geology were illustrated. They include the visual modeling of rock-mass quality classification,the arbitrary slicing analysis of the 3D model,the geological analysis of the dam,and underground engineering. They provide powerful theoretical prin-ciples and technical measures for analyzing the geological problems encountered in hydraulic and hydroelectric engineering under complex geological conditions.

关键词： 3D integrated model engineering geology geological analysis hydraulic and hydroelectric project

Perceived ill-health and health seeking behavior in two communities in the nam theun 2 hydroelectric project area in Lao Peoples Democratic Republic

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Asian Pacific Journal of Tropical Medicine 2009年第6期2卷 63-70页

作者： Sayasone S Erlanger TE Kaul S Sananikhom P Tanner M Utzinger J Odermatt P Department of Public Health and Epidemiology Swiss Tropical InstituteBaselSwitzerland Institut de la Francophonie pour la Medecine Tropicale VientianeLao PDR International SOS Singapore Nam Theun 2 Power CompanyVientianeLao PDR Nam Theun 2 Power Company VientianeLao PDR

Objective:To compare perceived ill-health and health seeking behavior between two communities affected by the large Nam Theun 2 hydroelectric project in central Lao People’s Democratic Republic(PDR).Methods: Two different affected areas;Nakai plateaubeing remote,sparcely populated and mountainous,and Xe Bang Fai lowland plains,more densely populated and comparatively affluent were included.Data were obtained from two cross-sectional household-based health and socio-economic surveys.Results:We found pronounced differences in the frequency of self-reported fever,cough,headache and myalgia according to location.On the Nakai plateau,45.1%of the individuals with ill-health report(recall period;2 weeks) went to a local health volunteer compared to only 7.2%in the Xe Bang Fai area(P hydroelectric project.

关键词： Self-reported ill-health Health seeking behavior Lao PDR Nam Theun 2 hydroelectric project

水轮发电机组在不平衡磁拉力及密封力下振动特性分析

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水电能源科学 2010年第9期28卷 117-120页

作者：张雷克马震岳宋兵伟大连理工大学建设工程学部水利工程学院辽宁大连116024 大阪大学日本豊中560-8531

通过将气隙磁导展开为Fourier级数得到不平衡磁拉力的解析式,建立了考虑电机磁极对数分布的不平衡磁拉力及水轮机转轮线性密封力的水轮发电机组轴系动力学模型,并推导了其运动微分方程。基于Matlab仿真工具采用四阶五级Runge-Kutta法对... 详细信息

通过将气隙磁导展开为Fourier级数得到不平衡磁拉力的解析式,建立了考虑电机磁极对数分布的不平衡磁拉力及水轮机转轮线性密封力的水轮发电机组轴系动力学模型,并推导了其运动微分方程。基于Matlab仿真工具采用四阶五级Runge-Kutta法对系统进行了数值分析计算,对比了发电机励磁电流及发电机转子质量偏心对转子转轮系统横向振动的影响。结果表明,励磁电流及质量偏心对转子转轮横向振动的影响均较为明显;同质量偏心相比,励磁电流增加到某一程度会显著加大发电机转子的振幅。

关键词：水轮发电机组不平衡磁拉力密封力振动特性分析 Sealing Force Pull hydroelectric Generating Set 质量偏心励磁电流横向振动 Runge-Kutta法发电机转子水轮机转轮运动微分方程 Fourier级数动力学模型 Matlab仿真系统气隙磁导分析计算

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立式水电机组轴承油膜压力分布计算

水电能源科学 2010年第9期28卷 121-124页

作者：李龙张伟清华大学机械工程系教育部先进成型制造重点实验室北京100084

基于立式水电机组的导轴承特点,详细介绍了油膜压力分布计算公式的推导过程、无量纲化过程及离散过程。在计算油膜压力分布时考虑了温粘效应,介绍了油膜温度分布的计算方法,给出了考虑油膜温度分布情况下油膜压力分布计算软件的实现算法... 详细信息

基于立式水电机组的导轴承特点,详细介绍了油膜压力分布计算公式的推导过程、无量纲化过程及离散过程。在计算油膜压力分布时考虑了温粘效应,介绍了油膜温度分布的计算方法,给出了考虑油膜温度分布情况下油膜压力分布计算软件的实现算法,设计了油膜压力分布计算软件并给出了计算结果,可为解决水电机组轴承间隙调整和轴瓦支承的寿命预测提供数据基础。

关键词：立式水电机组轴承间隙调整油膜压力分布压力分布计算 hydroelectric Generating Set Pressure Distribution 油膜温度温度分布计算软件温粘效应推导过程数据基础寿命预测离散过程计算结果计算公式计算方法分布情况无量纲

Interior-Point Methods Applied to the Predispatch Problem of a hydroelectric System with Scheduled Line Manipulations

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American Journal of Operations Research 2012年第2期2卷 266-271页

作者： Silvia M. S. Carvalho Aurelio R. L. Oliveira University of Campinas Campinas Brazil

Transmission line manipulations in a power system are necessary for the execution of preventative or corrective main- tenance in a network, thus ensuring the stability of the system. In this study, primal-dual interior-point methods are used to minimize costs and losses in the generation and transmission of the predispatch active power flow in a hydroelectric system with previously scheduled line manipulations for preventative maintenance, over a period of twenty-four hours. The matrix structure of this problem and the modification that it imposes on the system is also broached in this study. From the computational standpoint, the effort required to solve a problem with or without line manipulations is similar, and the reasons for this are also discussed in this study. Computational results sustain our findings.

关键词： Interior-Point Methods Scheduled Line Manipulations hydroelectric Systems The Brazilian Power System

On the Origin of the Cavities Present in the Sandstone Formations of the hydroelectric Development Site of Kakobola and Its Surroundings (Kwilu Province/DRC)

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Journal of Geoscience and Environment Protection 2023年第4期11卷 170-191页

作者： Ivon Ndala Tshiwisa Thomas Kanika Mayena Dominique Wetshondo Osomba Albert Mbata Muliwavyo Brich Kalanga Kabuya Jonathan Musitu Muliwavyo Clement N’zau Umba-Di-Mbudi Geo-Hydro-Energy Research Group Geosciences Department Faculty of Sciences and Technologies University of Kinshasa Kinshasa XI Democratic Republic of Congo Geosciences Department Faculty of Sciences and Technologies University of Kinshasa Kinshasa XI Democratic Republic of Congo Physic Department Faculty of Sciences and Technologies University of Kinshasa Kinshasa XI Democratic Republic of Congo Polytechnic Faculty President Joseph Kasa-Vubu University Boma Democratic Republic of Congo

Problems due to underground cavities at the level of soft and polymorphic sandstones, collapses and infiltration of acid waters through the fracture networks have been observed around the Kakobola hydroelectric development, constituting potential risks for the stability of the dam. The objective of this article aims to highlight the major cause that can explain the generating processes of these cavities. Indeed, to do this, the exploration of the subsoil was made possible thanks to the eleven (11) boreholes drilled on the site, the determination of cavities by the method of colored tracers and the petrographic characterization using a microscope. The latter, by means of thin sections, reveals the presence of quartz arenites. The mineralogical characterization of rock materials was carried out using X-ray fluorescence and X-ray diffraction methods. X-ray fluorescence revealed the presence of nickel, zinc and iron. Diffraction shows us an abundance of silica, mainly quartz and its metastable phases, in particular tridymite and cristobalite. It also made it possible to question the presence of carbonated minerals. The drillings enabled us to elaborate the logs and to bring out a geological model of the sector of study. These models were produced on the basis of drilling and observations on excavation. These data also reveal the presence of underground cavities which were also confirmed by the colored tracer method. These cavities would be of natural origin due to the presence of carbonate minerals observed in the rocks and which are attacked by acidic waters attested by the pH 5 measurements of the waters of the Lufuku River. The infiltration of water in rocky materials of low density and through the various networks of fractures and cavities leads to instability of the rock and could damage the hydroelectric development.

关键词： Development Cavity Drilling Sandstone hydroelectric Kakobola

Self-Tuning Control Techniques for Wind Turbine and hydroelectric Plant Systems

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Journal of Power and Energy Engineering 2019年第1期7卷 27-61页

作者： Silvio Simani Stefano Alvisi Mauro Venturini Department of Engineering Ferrara University Ferrara Italy

The interest on the use of renewable energy resources is increasing, especially towards wind and hydro powers, which should be efficiently converted into electric energy via suitable technology tools. To this aim, self-tuning control techniques represent viable strategies that can be employed for this purpose, due to the features of these nonlinear dynamic processes working over a wide range of operating conditions, driven by stochastic inputs, excitations and disturbances. Some of the considered methods were already verified on wind turbine systems, and important advantages may thus derive from the appropriate implementation of the same control schemes for hydroelectric plants. This represents the key point of the work, which provides some guidelines on the design and the application of these control strategies to these energy conversion systems. In fact, it seems that investigations related with both wind and hydraulic energies present a reduced number of common aspects, thus leading to little exchange and share of possible common points. This consideration is particularly valid with reference to the more established wind area when compared to hydroelectric systems. In this way, this work recalls the models of wind turbine and hydroelectric system, and investigates the application of different control solutions. Another important point of this investigation regards the analysis of the exploited benchmark models, their control objectives, and the development of the control solutions. The working conditions of these energy conversion systems will also be taken into account in order to highlight the reliability and robustness characteristics of the developed control strategies, especially interesting for remote and relatively inaccessible location of many installations.

关键词： Wind Turbine System hydroelectric Plant Simulator Model-Based Control Data-Driven Approach Self-Tuning Control Robustness and Reliability

Delineation of Cavity in Downstream Surge Chamber at Punatsangchhu-II hydroelectric Project, Bhutan

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Journal of Geological Research 2019年第1期1卷 5-11页

作者： B.N.V.Siva Prasad A.P. Thapliyal Rabi Bhusan Sripad R. Naik Scientist National Institute of Rock MechanicsBengaluruIndia Senior Geologist Geological Survey of IndiaDehradunIndia

On 3^rd March, 2016, there occurred a massive roof fall incidence in one of the major caverns of Punatsangchhu-II hydroelectric Project (PHEP-II), Bhutan which halted the operations in the major caverns and required additional strengthening measures. Prior to concluding any thing on the treatment measures for the muck flown into the cavern and the cavity formed over the crown of Downstream Surge Chamber, there was a strong need to determine the extents of cavity. Even to understand the influence of cavity formation on adjacent caverns, the cavity needs to be delineated. Therefore, the management of PHEP-II adopted several techniques to decipher the shape and dimensions of the cavity like, surveying, geophysical, cross-hole seismic surveys, borehole scanning, and exploratory drilling. The tentative shape of the cavity could finally be established. The findings from each method are explained in this paper.

关键词： Cavity Large caverns hydroelectric project Tomography Cavity monitoring system