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介绍了二滩水电站调速器的总体结构,微机调节器的工作原理和应用效果。微机调节器由两套相互独立相互通讯的Quantum系列PLC控制,具有独立的供电电源系统、独立的信号采样(机组频率、导叶开度、有功功率等)通道和独立的输入输出通道。调速器实现双微机调节器及其输入输出通道的交叉冗余,并进行适应式变参数的转速调节和功率调节。着重描述了交叉冗余双微机调节器的容错控制和功率控制方法。 相似文献
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二滩水电站调速器的交叉冗余双微机调节器 总被引:6,自引:6,他引:0
介绍了二滩水电站调速器的总体结构、微机调节器的工作原理和应用效果。微机调节器由2套相互独立、相互通信的Quantum系列可编程逻辑控制器(PLC)控制,每一套PLC具有独立的供电电源系统、独立的信号采样(机组频率、导叶开度、有功功率等)通道和独立的输入输出通道。调速器实现双微机调节器及其输入输出通道的交叉冗余,并进行适应式变参数的转速调节和功率调节。着重描述了交叉冗余双微机调节器的容错控制和功率控制方法。 相似文献
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文章介绍了湖南洪江水力发电厂调速器的总体结构,微机调节器的工作原理和应用效果。微机调节器由两套相互独立相互通讯的Quantum系列PLC控制,具有独立的供电电源系统、独立的信号采样(机组频率、导叶开度、有功功率等)通道和独立的输入输出通道。调速器实现双微机调节器及其输入输出通道的交叉冗余,并进行适应式变参数的转速调节和功率调节。 相似文献
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我国水轮机调速技术创新回顾与学科前景展望 总被引:1,自引:1,他引:0
对我国水轮机调速器的技术与产品发展情况进行了全方位介绍,回顾了我国水轮机调速器技术创新历程,从调速器的系统结构模式、微机调节器的构成、电液转换元件的多元化、系统冗余问题、计算机仿真测试功能、友善且内容丰实的人机界面,以及调速器工作油压等级提高等方面进行了总结.结果表明:我国水轮机微机调速器产品的主要技术性能指标一般都已... 相似文献
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我国水轮机调速技术最新进展与展望 总被引:3,自引:0,他引:3
通过分析国内水轮机调速器研制生产厂家的最新调速器技术水平,从调速器的系统结构模式、以工业控制计算机构成的微机调节器、计算机双机冗余问题、友善且内容丰实的人机界面、调速器的计算机仿真测试功能、采用工业标准液压件如比例伺服阀或伺服电机构成的电液转换部件、机械反馈和机械开度限制机构的设置、普遍提高的调速器油压等级等方面进行了总结。结果表明:我国水轮机微机调速器产品的主要技术指标都达到了国家技术标准的要求,部分厂商的的产品技术指标达到了国际先进水平。同时,从“努力贯彻有关水轮机调速器各类标准”等5个方面提出了我国水轮机调速技术的努力目标。 相似文献
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公伯峡水电站调速器的交叉冗余实现方案 总被引:1,自引:1,他引:0
介绍了公伯峡水电站(5×300MW)微机调速器的交叉冗余实现方案、双机切换原则和切换方法,同时指出了双可编程逻辑控制器(PLC)微机调速器在国内大型、巨型水轮发电机组上运行的可行性。 相似文献
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三菱公司CC-Link总线技术具有很高的性价比和可靠性。文中介绍了CC-Link在双微机调速器系统交叉冗余结构中实现交换数据的结果,指出大型(或巨型)机组采用中国自行研制的双可编程微机调速器是可行的。 相似文献
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结合水轮机调速器的发展过程,着重介绍了龙滩水电站水轮机调速器采用T.SLG型功能组合式数字调节器组成的双冗余微机数字控制器+全液控电液随动系统,分析了该调速器的特点和设计及运行中存在的问题。 相似文献
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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
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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
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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
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V. K. Konovalov O. V. Yashkin V. V. Ermakov 《Power Technology and Engineering (formerly Hydrotechnical Construction)》2008,42(2):105-109
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.
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Translated from élektricheskie Stantsii, No. 2, pp. 26–30 (2008). 相似文献
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Peter B. Bayley 《河流研究与利用》1991,6(2):75-86
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
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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