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1.
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。  相似文献   

2.
分析了基于IEC 61850体系的变电站自动化信息交换体系结构,基于数字证书和代理多重签名体制,提出一种实用与发展并重的变电站自动化信息交换安全认证体系。在变电站智能电子设备(IED)或变电站通信控制器中集成密码计算模块,采用普通的或代理的数字签名模式,实现信息交换过程中控制中心与变电站IED身份和信息完整性的认证。该安全认证体系符合IEC 61850标准体系,密码计算采用国家密码管理委员会办公室指定的密码技术。  相似文献   

3.
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。  相似文献   

4.
报文的通信延迟包括传输延迟和处理延迟2部分。IEC 61850标准将面向通用对象的变电站事件(GOOSE)报文直接映射到数据链路层,能有效减少传输延迟。文中对GOOSE报文在变电站智能电子设备(IED)中的处理延迟进行了研究。分析了前后台方式的嵌入式系统在变电站IED中处理实时报文方面的不足,提出在IED中采用具有强实时内核的操作系统,并针对IED中实时报文和非实时报文混合处理环境需求,在RTAI实时操作系统上设计了保障GOOSE报文处理实时性的方案。实验验证了该方案的有效性和实用性。该研究结果对于使用IEC 61850的变电站IED过程总线通信设计具有参考意义。  相似文献   

5.
依据电力系统数据与通信安全标准IEC 62351,研究既能满足认证安全需求,又能保证最小的计算和传输开销,基于口令的变电站数据与通信安全认证方法。比较了几种国际上先进的安全口令技术,分析了IEC 61850标准中智能电子设备(IED)访问安全模型,提出采用安全远程口令(SRP)协议实现IED访问应用关联时的安全认证。最后,以变电站自动化IED间的身份鉴别为例,介绍了SRP协议的改进方法和具体的认证过程。研究结果对在变电站自动化系统中实施 IEC 62351标准具有参考意义。  相似文献   

6.
分析了集中式和分布式变电站程序化控制实现方案的优缺点,提出了一种不依赖于站级网络通信协议、以间隔层智能电子设备(IED)为核心的分布式变电站程序化控制实现方案,操作票的存储、执行及操作逻辑的判断均在IED中实现,程序化控制过程中需要操作其他IED则请求站控层设备执行。该程序化控制方案已在CSC-2000变电站自动化系统中实现。该方案既适用于站级网络协议为IEC 61850等国际标准的变电站自动化系统,也适用于站级网络协议为以太网IEC 60870-5-103协议、 CSC-2000协议等企业标准的变电站自动化系统,尤其适合在IEC 61850标准还没有完全普及的过渡时期采用。  相似文献   

7.
面向通用对象的变电站事件(GOOSE)是IEC 61850标准用于解决智能电子设备(IED)之间实时信号通信的多播通信机制,但标准中推荐的多播报文过滤方法在实际工程中不具备可操作性。分析和比较了3种多播报文过滤机制的特点,认为静态配置交换机多播过滤是目前IEC 61850变电站应用GOOSE切实可行的方案,提出了交换机配置定值化管理的概念。交换机配置定值化管理是数字化变电站的必然趋势。IEC 61850标准应采纳统一的动态多播地址管理协议实现交换机动态多播地址过滤,以简化变电站网络设备的管理。  相似文献   

8.
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。  相似文献   

9.
结合基于IEC 61850标准的变电站自动化系统试点工程,提出IEC 61850自动化系统网络通信黑匣子的设计原理,实现对自动化系统网络通信故障全过程的追忆,为运行维护人员提供网络通信过程的可视化工具,辅助维护人员准确定位故障原因,在变电站自动化系统的联调及运行维护中发挥其重要作用。  相似文献   

10.
变电站通信网络和系统系列标准——IEC 61850正在成为变电站自动化的一个重要标准。文中从形式语义的角度出发,对IEC 61850的建模方法和所给出的模型进行了研究。提出“语义空间”的概念,给出“语义空间”构成“偏序集”的推断,并从语义空间的数据通信基础、语义空间的结构、语义空间的可伸缩条件等方面对IEC 61850模型的语义空间做出分析,与传统自动化系统进行比较,发现和挖掘上述几个方面与“互操作性”的关系,寻找满足IEC 61850“互操作性”的基本语义形式。  相似文献   

11.
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。  相似文献   

12.
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.  相似文献   

13.
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。  相似文献   

14.
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。  相似文献   

15.
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.  相似文献   

16.
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。  相似文献   

17.
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).  相似文献   

18.
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.  相似文献   

19.
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。  相似文献   

20.
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。  相似文献   

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