凸极同步发电机定子绕组内部故障暂态仿真及试验验证

同步发电机定子绕组内部故障分析是一个十分复杂而重要的问题。文中在建立同步发电机定子绕组内部故障暂态计算模型时采用通用支路电压矩阵方程来建立回路电流方程，具有简洁、通用性强的特点。利用多回路理论着重对同步发电机带载时定子绕组内部故障暂态全过程进行了仿真计算，并与试验录波波形进行了对比，结果表明这种仿真方法能够准确地模拟同步发电机故障暂态过程。文中还分析了影响暂态过程仿真精度的因素，认为铁心局部饱和、铁心剩磁、转速变化及回路电阻变化是产生仿真误差的重要原因。     

龙滩水电站转子电压二次回路改造

根据龙滩电站转子电压二次回路现状，分析了存在的隐患，结合工程实际和相关设计规程，给出了转子电压二次回路的改造方案，经改造后既满足了保护和故障录波等二次系统的要求，又兼顾了一次系统的安全，具有实用价值。     

发电机电气量采集与故障录波装置研制与应用

丰满发电厂自行研制的FCGL2008B型发电机电气量采集与故障录波装置成功地在丰满发电厂多台机组上得到应用.文中介绍了该装置的构成原理及技术特点,所采用的NI LabVIEW图形化编程软件和CompactRl0可编程控制器相结合的设计方案,有效提高了该装置的性能,为现场电力系统电气量采集与故障录波装置研究应用提供技术参考.     

智能故障录波在变电站仿真培训系统中的应用

本文简述了变电站仿真培训系统的作用,提出了可以应用到变电站仿真培训系统中的逻辑故障录波方法和数值故障录波方法,利用数字实时仿真软件对逻辑故障录波方法进行了设计和实现.     

基于模式的电力系统通用可扩展故障分析软件系统

针对现有故障分析软件的缺点和不足，提出了基于模式的电力系统通用故障分析软件设计思想，采用C++模板库（STLPort，Boost）技术和模式设计思想实现了录波显示控制引擎和可扩展的电力故障集成分析环境，阐述了录波显示控制引擎和可扩展的电力故障集成分析环境的体系结构，以及设计过程中使用的关键设计模式。     

基于同步相量的电力实时动态监测装置

介绍一种基于同步相量的电力实时动态监测装置,采用全嵌入式设计,全面提高了系统的可靠性和抗干扰能力;利用高精度测距技术很好地适应线路参数变化带来的测距误差。该装置集同步相量测量、故障录波、实时监测和连续记录为一体,既可作为电力系统动态安全稳定分析的依据,也可为超长时间、大范围和发展性的事故分析提供可靠的数据源。     

基于ICMMS的抽水蓄能调速器研究

基于ICMMS思想设计了新型抽水蓄能调速器，其故障诊断单元可进行故障的类别确定、定位、趋势分析。不仅使调速器本身运行可靠，而且还向预知维护子系统实时地提供状态、态势信息，便于故障处理，简化了维护子系统设计。传感器冗余设计进一步提高了系统可靠性。还设计了水泵优化控制、菜单式中文彩色图形界面、动态录波和性能指标计算等功能。现场运行经验证明，该系统运行可靠。     

基于嵌入式多芯片模组的故障录波系统

本文介绍了一种新开发的高性能的微机型故障录波系统,其设计基于嵌入式中央处理多芯片模组,并集成了高速数据采集模块和以太网(Ethernet)通信模块,以及采用全球定位系统(GPS)实现全网统一,具有监测通道多、采样频率高、实时性强、录波起动灵敏可靠以及数据传送快速等优点。本文详细介绍了该系统的软硬件结构和功能,并分析了故障录波起动算法。     

三峡左岸电站机组故障录波装置介绍

三峡水利枢纽左岸厂房工程发变组故障录波采用GTW-1603F型发变组故障录波系统，这套系统既具备了传统录波系统的功用和性能，同时也在多方面具有其自身的特点。本文就三峡左岸电站机组故障录波系统的强大功能作了全面系统的介绍，为同类系统提供一些参考。     

SJ-90振动摆度监测装置及其在水电机组在线监测系统的应用

随着水电机组单机容量不断增大,为保证机组和电网安全稳定运行,对机组振动摆度进行状态监测越来越重要.文中介绍了一种采用嵌入式软硬件技术开发的SJ-90振动摆度监测装置,对该装置的软硬件结构、系统功能以及在水电机组在线监测系统中的典型应用进行了阐述.作为一个独立的在线监测分析智能化单元,SJ-90装置集高速同步信号采集、丰富的数据显示分析、高效数据传输、可靠稳定运行、全面故障告警及故障录波、在线采集模块更换及采集参数更改等特点于一身,在水电机组在线监测领域具有良好的应用前景.     

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。     

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。     

浅谈天湖水电站水轮机运行故障及处理措施

简述天湖水电站投运以来各种故障的表现形式，分析其原因，提出了相应的处理方法及措施，并对合理利用国内外设备提出建议。