基于IEC61850标准的广域后备保护系统应用研究

电网快速发展与日益复杂给电力系统稳定控制带来巨大挑战,继电保护第一道防线的作用更加凸显。由于缺乏全局考虑的传统继电保护整定配合存在整体时间过长等不足,随着通信技术的发展尤其是IEC61850标准的推进,广域保护控制成为解决复杂电网系统稳定控制问题的有效方法之一。鉴于此,笔者分析了现有传统继电保护存在的问题,研究了广域后备保护系统主要功能及原理,包括自适应广域差动保护、广域开关失灵保护等,并研究了广西电网基于IEC61850的广域后备保护系统建模方案,给出了基于IEC61850标准的广域后备保护控制系统架构及功能。该系统已在广西来宾110 kV电网中试运行,运行情况良好。     

基于IEC 61850标准的新型集中式IED

基于IEC 61850标准的变电站自动化是一种必然趋势。站级总线、过程总线的应用对间隔层智能电子设备（IED）网络接口的实时性、可靠性有很高要求，且数量众多的间隔层IED使变电站网络接线复杂。计算机技术的快速发展使硬件的集成度越来越高，可靠性大幅度提升，间隔层设备将会向集成一体化方向发展，使设计理念为面向变电站整体功能，有利于控制、保护功能的协调并大幅度减少IED数量。提出了一种遵循IEC 61850标准的间隔层新型集中式IED方案，在1台新型集中式IED上实现多台IED所完成的功能，分析研究了其硬件方案、软件结构及内部信息交换方式等关键技术，为实施基于IEC 61850标准的变电站自动化系统提供了一种新的解决方案。     

应用于智能水电站的励磁系统建模与实现

IEC61850是国际电工委发布的,目前为止最完善的电力自动化系统通信标准。实现基于IEC61850标准技术体系的智能化发电站也必将对我国智能电网的建设带来深远影响和变革。智能发电站建立在IEC61850协议的基础上,由电子式互感器、智能化开关及智能化二次设备等分层构建。其实现基础是设备智能化、通信网络化和通信协议统一化,核心是实现智能电气设备间信息共享和互操作。本文主要对水电站励磁系统进行分析,讨论了基于IEC61850通信标准的励磁系统IED建模,并提出适用于智能化水电站的励磁系统IEC61850标准通信的实现方法。     

IEC 61850标准一致性测试的方案和现场应用

介绍了一致性测试仿真环境的基本构成，包括智能电子装置（IED）服务器端模拟器、客户端监控软件、系统配置工具、IED配置工具和协议分析工具。在分析现场测试需求的基础上，提出了实现变电站内IEC 61850标准一致性测试的总体方案。应用IEC 61850标准一致性测试与仿真培训系统，针对西安供电公司2个110 kV变电站进行了完整的测试。通过分析和研究测试结果，验证了变电站支持的IEC 61850功能，对数据模型等存在的问题进行了探讨。     

基于IEC 61850的保护功能交互模型

为了更好地实现基于IEC 61850的分布式功能的标准化设计、促进系统的工程实施，需要对保护功能在智能电子设备（IED）之间、IED内部逻辑节点（LN）之间的交互关系进行严谨的描述。文中为IED的交互过程构建了一个较统一的功能模型，阐述IED之间、IED内部LN之间的交互类型，采用扩展协作图和时序图分别刻画分布式保护功能下各LN之间的协作和时序关系，设计了IED的软件结构，为互操作测试实验提供了一定的参考。     

IEC 61850信息模型一致性的检验和控制方法

从继电保护故障信息系统的管理需求出发，针对继电保护等智能电子设备（IED）信息条目和语义缺乏统一的问题，提出一种以IEC 61850信息模型为管理对象、采用信息语义理论和面向对象理论的IED信息模型一致性检验及控制的方法。该方法能够将语义字典的管理由静态行为转变为面向过程的动态管理，以实现二次系统信息语义的一致性，并使其发展及变化过程受控。     

IEC 61850在继电保护故障信息处理子站系统中的应用

变电站继电保护故障信息处理子站系统是变电站通信网络与系统中一个具有特殊功能的智能装置。文中提出了IEC 61850在继电保护故障处理子站系统的应用特点,并对其应用进行了合理的裁减，同时探讨了保护故障信息协议转换的不同模式。应用的核心为子站的上行接口应符合IEC 61850的标准，实现其向其他主站开发商开放。     

基于IEC 61850的电力设备远程控制方法

远程控制已成为确保电力系统安全稳定运行的重要技术手段,IEC 61850对电力设备的远程控制提出了更高的要求。以增强安全的操作前选择控制的有限状态机为基础,提出了基于IEC 61850的电力远动系统的远程控制模型。结合实际应用的需要,设计了基于IEC 61850的远方控制接口,实现了对智能电子设备（IED）的远程访问控制,对断路器进行了断开与闭合操作。基于上述研究所开发的系统通过了在某地区电网进行的工业现场试验并试运行,验证了模型的正确性和方案的可行性。     

采用IEC 61850构造变电站广域保护代理的信息模型

基于代理（Agent）技术的广域后备保护有助于提高电网安全，因此得到人们的关注和研究。文中提出采用IEC 61850构造变电站广域后备保护代理的信息模型。阐述广域后备保护系统分布式对等协商的一般性体系结构，研究保护智能电子设备（IED）中包括广域后备保护代理在内的逻辑节点组成。将保护代理设计成扩展型逻辑节点，具有接口层、高级处理层、基本服务层嵌套对象结构。根据一种广域保护算法，阐述基于多任务的保护代理与其他逻辑节点的协作流程和设计。研究位于不同变电站的保护代理之间点对点远程通信原理，分两阶段提交。协商消息以面向通用对象的变电站事件（GOOSE）等报文为基本内容，采用用户数据报协议（UDP）或传输控制协议（TCP）区分传输。广域后备保护代理模型在EPOCHS平台得到仿真实现和验证。     

基于IEC 61850标准的IED图形化编程技术

IEC 61850标准的互操作及功能自由分布特性要求变电站自动化系统中不同智能电子设备（IED）间更灵活地协同。提出一种图形化编程技术的IED开发方法，它基于IEC 61850标准，遵循IEC 61131-3编程标准，不仅具有常规图形化编程的优点，而且提升了IED外在形态和内在形态的标准性。设计一种IED软件方案，研究图形化编程与IED数据存储区的参数关联方法，为推进产品编程开发手段的灵活性、标准化，提高产品互换性提供了一种解决方案。     

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.     

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.     

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。     

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。     

Desiccation and recolonization of phytobenthos in a regulated desert river: Colorado River at Lees Ferry,Arizona, USA

We tested the recolonization of the phytobenthic community in the tailwaters of Glen Canyon Dam following long- and short-term experimentally induced desiccation. The response of Cladophora glomerata, Oscillatoria spp., miscellaneous phytobenthos species and periphyton was studied over 18 weeks using three treatments: (1) undisturbed control cobbles from the submerged zone; (2) cobbles desiccated and replaced into the submerged zone; and (3) cobbles desiccated and replaced into the varial zone. Periphyton density and compositional response resulting from these treatments were also examined. Desiccation treatments were significantly different in biomass from controls throughout the study. The biomass of desiccated and replaced river cobbles averaged <30% of the controls for C. glomerata and periphyton during the 18-week recolonization period. In contrast, the biomass of the control Oscillatoria and miscellaneous phytobenthos species averaged only 3 and 50% of that in the desiccation treatments, respectively. Cladophora, the dominant alga, comprised 77% of the phytobenthic biomass. A significant positive relationship between discharge, Cladophora and periphyton biomass was present in all treatments, while there was a negative relationship with discharge for Oscillatoria and miscellaneous phytobenthos species. There was a significant inverse correlation, as well as a pattern of separate biomass dominance, between C. glomerata and Oscillatoria. Cladophora was the dominant phytobenthos species on cobbles below the baseflow and Oscillatoria was dominant on cobbles in the varial zone. In general, the Cladophora biomass decreased under intermittent drying conditions, while Oscillatoria declined under permanently wet conditions. Diatom composition was not significantly different between treatments; however, their density was lower on desiccated cobbles. Diatom density on desiccated cobbles in the submerged and varial zones averaged 69 and 42% of that of the controls, respectively. Recovery and maintenance of benthic resources are hindered by fluctuating flow regimes driven by electricity and irrigation requirements. Repeated desiccation of the phytobenthos has major effects on the bottom-up interactions in the Colorado River ecosystem. © 1998 John Wiley & Sons, Ltd.