一种实用的水电厂机组启停与负荷分配模型

借鉴虚拟机组技术，通过将机组工况转换成本转换成水当量来计算，建立了一种实用的水电厂机组启停与负荷分配模型。该模型既尽量减少水电厂发电耗水量，又尽量减少机组启停次数和通过机组汽蚀振动区的次数。在模型求解过程中将动态规划和网络最短路径搜索有效地结合，模型求解的结果能在发电耗水成本和机组工况转换成本之间取得较好的平衡，从而有效地降低水电厂发电的综合成本。该模型在对隔河岩水电厂实时经济运行的离线仿真应用中获得了较好的效果。     

小型水电厂自动发电控制技术研究

小型水电自动发电控制技术对于促进小型水电厂自动化的全面提升有着不可替代的重要作用。文章以小型水电厂自动发电控制技术的研究作为出发点展开讨论,对开展自动发电技术研发的必要性进行了简述,并对自动发电控制技术的相关内容进行了概述,随后对小型水电厂自动发电控制系统设计,和其中的关键点进行了简要说明。     

广州蓄能水电厂SCADA自动发电控制功能设计及应用

为了适应电网日益严格的调峰调频要求,广州蓄能水电厂对计算机数据采集与监控(SCADA)系统进行了全面改造升级,对其自动发电控制功能进行了重新优化设计.文中详细介绍了广州蓄能水电厂SCADA系统2种有功控制的计算方式,即功率调节方式和频率调节方式,对今后电厂自动发电控制程序的设计有参考意义.     

广州蓄能水电厂对于广东电网安全运行的重要性

介绍了广州蓄能水电厂机组对于广东电网安全运行的重要性，从发电和抽水的事例分析了调度员乐意直接控制广州蓄能水电厂机组，在系统出现大功率缺额事故时，广州蓄能水电厂为系统提供快速备用。     

基于改进遗传算法的水电厂经济运行研究

随着电力市场化的逐步实施,发电企业将会参与市场竞争.水电厂经济运行能提高1%～3%的水力效率,水电厂应尽快实现经济运行.以丰满水电厂发电机出力与耗流量函数为基础,应用改进遗传算法对水电厂进行计及开停机的优化调度计算.在改进遗传算法中,采取了自适应和精英保留策略以及移民算子,提出了方向性变异的观点,改进了变异方法.计算结果与自动发电控制(AGC)方法进行了比较,表明算法具有一定的优势.     

基于西藏电网下的多布水电厂AGC的设计与应用

在介绍多布水电厂自动发电控制(AGC)系统的实现原理、约束条件和负荷分配策略的基础上,通过程序实现调度对水电厂AGC与一次调频配合关系及负荷调节速率的方式。     

基于CSPA-2000的智能水电厂解决方案

以CSPA-2000水电厂监控系统为基础,针对CyberControl上位机组态软件和CSC-850可编程逻辑控制器进行智能化设计,从机组现地控制单元（LCU）、开关站LCU、公用LCU、嵌入式自动发电控制/自动电压控制子站、嵌入式远动工作站的智能化实现,以及数据中心的智能化建设等角度,探讨了水电厂智能化的解决方案。在此基础上阐述了智能水电厂的信息化模型。     

AGC在长洲水利枢纽的应用实践

介绍长洲水利枢纽发电厂自动发电控制（AGC）的原理、运行操作方式以及画面控制功能等。水电厂自动发电控制模式既保证厂用系统的安全和公用电力系统的稳定,又满足机组的最佳经济运行条件,使电厂灯泡贯流式机组取得较好的经济效益。     

流域梯级集控及水电厂智能化建设规划初探

作为智能电网发电环节的重要组成部分,流域梯级集控及水电厂智能化建设是配合国家智能电网建设战略发展的必然趋势,对提高电网电能质量和安全稳定性,实现发电企业经济和社会效益最优化具有重要意义。同时随着国内水电厂"远程集控,无人值班,少人值守"模式的日渐成熟和信息网络技术的不断进步,也为水电智能化发展创造了良好条件,为电厂进一步实现维护人员后撤,真正实现"关门电厂"提供了技术支撑。本文在广泛调研目前国内水电智能化发展现状,并结合五凌公司集控中心和各水电厂实际的基础上,就流域梯级集控及水电厂智能化建设规划提出了一些建议。     

枯水期降低水耗、提升发电量运行管理模式

水电厂实现了将水能转换为电能,但水电厂的发电量很大程度上取决于来水量的多少。在每年枯水期时,因来水量减少,如何利用有限的来水高效的发电,就成了水电厂提质增效的关键。鲁地拉水电厂在机组投产以来平、枯水期降低水耗、提升发电量"运行管理模式,该运行管理模式对于水电厂,尤其是大型水电厂、梯级水电厂具有普遍适用性,可真正实现水电厂降低水耗、提质增效的目标。     

地下厂房施工过程的三维非线性数值模拟分析

根据冗各电站地下厂房开挖支护的施工顺序,以隐式杆单元模拟锚杆,以壳单元模拟混凝土喷层,采用三维非线性有限元技术,对洞室群的开挖支护动态过程进行了模拟计算。通过三维非线性有限元计算分析得到:洞室群动态开挖过程中围岩应力变形的分布规律,围岩塑性区的发展规律,锚杆受力变化情况。计算结果表明:整个开挖过程中,洞周围岩位移变化规律正常,量值较小,塑性区主要分布在洞室周边,围岩稳定性较好;但在洞室交叉口处围岩的变形较大,出现较大范围的塑性区,在此基础上提出了支护措施优化方案,并对优化方案的效果进行了评价。     

Evaluation of freshwater mussel relocation as a conservation and management strategy

The relocation of unionacean mussels is commonly used as a conservation and management tool in large rivers and streams. Relocation has been used to recolonize areas where mussel populations have been eliminated by prior pollution events, to remove mussels from construction zones and to re-establish populations of endangered species. More recently, relocation has been used to protect native freshwater mussels from colonization by the exotic zebra mussel Dreissena polymorpha. We conducted a literature review of mussel relocations and evaluated their relative success as a conservation and management strategy. We found that 43% of all relocations were conducted because of construction projects that were forced to comply with the Endangered Species Act 1973 and that only 16% were monitored for five or more consecutive years. Most (43%) relocation projects were conducted from July to September, presumably a period when reproductive stress is relatively low for most species and the metabolic rate is sufficient for reburrowing in the substrate. The mortality of relocated mussels was unreported in 27% of projects; reported mortality varied widely among projects and species and was difficult to assess. The mean mortality of relocated mussels was 49% based on an average recovery rate of 43%. There is little guidance on the methods for relocation or for monitoring the subsequent long-term status of relocated mussels. Based on this evaluation, research is needed to develop criteria for selecting a suitable relocation site and to establish appropriate methods and guidelines for conducting relocation projects.     

基于模型试验的河床砂砾石层基本特性研究

为了经济可靠地确定深厚覆盖层的基本特性参数,以大渡河双江口水电站坝基河床砂砾石层基本特性研究为工程背景,进行大尺寸模型试验,研究河床砂砾石层的旁压模量和动探击数随密度、级配以及上覆压力的变化规律。根据室内模型试验结果,结合现场旁压试验及钻孔试验成果,推断出坝址区河床砂砾石相关层位的密度,并依此进行砂砾石室内力学试验,获得设计所需力学参数。研究成果可为深厚覆盖层基本特性测试提供新的方法。     

Serial discontinuities in a Rocky mountain river. I. Distribution and abundance of plecoptera

Samples were taken year-round at eleven sites along the altitudinal profile (2900-1400 m a.s.l.) of the Gunnison River, a 329 km tributary of the Colorado River, to document the distribution of the Plecoptera and to evaluate responses to hypolimnial-release dams in the headwaters and middle reaches. Twenty-two species were present, with the greatest species richness occurring in an unregulated segment upstream of the middle reach dams; average nymphal biomass over the study period (175 organisms, 395 mg dry mass m^?2) was also greatest in this segment. Only four species (58 organisms, 48 mg m^?2) were present in the tailwaters of the headwater dam and values were greatly reduced (nine species; 35 organisms, 180 mg m^?2) below the middle reach dams. The stonefly community recovered ca. 80 km downstream from the last dam (15 species; 244 organisms, 250 mg m^?2), apparently in response to natural resetting of environmental conditions corresponding to those above the middle reach dams. At the most downstream site (11) only four species (four organisms, 16 mg m^?2) were present. The observed distributional pattern is a classic serial discontinuity in response to hypolimnial stream regulation in a temperate latitude river.     

基于BP神经网络-马尔科夫链模型的隧道围岩位移预测

在隧道工程施工中,围岩位移预测起着很重要的作用。将BP神经网络-马尔科夫链模型引入到隧道围岩位移预测中来,通过对训练样本的学习,利用BP神经网络实现了对位移时间序列的滚动预测,同时得到了实测值与预测值的相对误差;在此基础上利用马尔科夫链对相对误差进行修正,有效地提高了预测结果的精度。并将该模型应用于某公路隧道拱顶下沉位移时序预测中,结果表明该模型具有精度高、科学可靠的特点,为隧道围岩变形的预测提供了新的途径。     

Short communication. Pipelines as a refuge for freshwater snails

In the lower River Murray, Australia, populations of gastropods have declined markedly over the past 40 years. Of the native fauna of about 18 species, only the ancylid Ferrissia petterdi remains common (but in patches), and another five species feature in sporadic local resurgences. Until recently the viviparid Notopala was thought to be extinct. The introduced physid Physa acuta is widespread, but in low numbers. The decline probably is associated with flow regulation, high turbidity and the introduction of common carp. Snail populations have persisted, however, in irrigation pipelines fed from the river, where they periodically cause blockages. This paper reports the discovery of the only known populaion of Notopala hanleyi in a pipeline where the inner wall accumulates microbial and other organic matter, providing high quality food for snails. In the Murray before regulation most of the periphytic biomass was probably microbial, as fluctuating water levels would have maintained littoral communities in a highly productive, early state of succession his postulated that, by stabilizing seasonal water levels, regulation has promoted the production of filamentous green algae, an inferior food source, and so displaced snail populations from the open aquatic environment.     

浙江省水域调查录入系统的设计和应用

浙江省水域调查录入系统将调查数据与电子地图相整合,对分类水域数据进行统计计算,并对输入数据进行合理性和完整性检查,得到调查范围内现有水域的详细数据,实现了水域调查数据输入、计算、统计和查询的数字化管理,提高了工作效率和工作质量,为各地下阶段水域保护规划编制和水域管理工作提供了数据支持。对该系统的设计原则、功能和技术设计等作了介绍。     

Automated system for removal and pneumatic transport of fly ash from electric precipitator hoppers

A system for removal and pneumatic transport of fly ash is examined, in which air pulses act on batches (pistons) of ash formed in a duct. Studies are made of the effect of several physical parameters on the force required to displace a piston of ash and these serve as a basis for choosing a system for removal and pneumatic transport of ash simultaneously from several hoppers of an electric precipitator. This makes it possible to separate the ash particles according to size without introducing additional components. Formulas are given for calculating the structural and dynamic parameters of this system and measurements of indirect dynamic parameters are used to calculate the input-output characteristics of the system. In order to optimize the system, configurations for summing several ducts into a single transport duct for pneumatic ash transport are proposed. Some variants of dry ash utilization and the advantages of producing of size-separated particles are considered. __________ Translated from élektricheskie Stantsii, No. 2, pp. 26–30 (2008).     

The flood pulse advantage and the restoration of river-floodplain systems

The ‘flood pulse advantage’ is the amount by which fish yield per unit mean water area is increased by a natural, predictable flood pulse. Evidence for this increase is presented from tropical and temperate fisheries. It is argued that increasing multispecies fish yield by restoring the natural hydrological regime is consistent with increasing production of other trophic levels and with restoration from ecological and aesthetic viewpoints. When applied to a river-floodplain system, this restoration would provide a large, self-sustaining potential for recreation, commercial exploitation, and flood control. An interim ‘natural flood pulse’ restoration approach is proposed for systems modified for navigation. This approach approximates the natural hydrological regime in a river reach and is intended as a first step in the long process of restoring the watershed.     

基于CT-连续加荷水泥乳化沥青混凝土细观损伤规律研究

利用CT技术对水泥乳化沥青混凝土的细观损伤过程进行实时扫描观测,获得了混凝土试件在连续加荷下的CT图像。通过采用直观分析法、CT数分析法、CT数与损伤变量关系3种方法分析表明,水泥乳化沥青混凝土的破坏过程可分为压密、扩容、裂纹扩展、破坏4个阶段,同时混凝土在受压过程中具有韧性,在极限荷载之前各断面处于压密和微扩容的强化阶段,极限荷载之后混凝土从损伤到破坏发展比较平稳。