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1.
风电场建设中风电工程设计是重要的一环,是风电场建设成败的关键,而风电场的场址选择又是风电工程设计的重点,场址的选择直接影响未来风电场的发电量。结合实际设计经验,对风电工程设计中的重要环节进行了介绍,并提出应注意的问题。  相似文献   

2.
介绍了目前我国风电能源发展的基本情况,分析了风电场对雷达工作性能的潜在影响因素。并分别提出了相应的分析方法和关键技术,可以为无线电管理部门深入开展风电场对雷达台站的影响分析提供技术支撑,在保障雷达工作性能以及我国风电场的建设规划论证中发挥重大作用。  相似文献   

3.
大型风电场并网会对电网的稳定运行带来一定的影响,在风电场内安装动态无功补偿装置是一种有效的方式,可以保证并网后系统的稳定性和风电机组低电压穿越能力。基于PSCAD构建了包含MCR型SVC的风电场模型,分别对不同的故障位置进行了仿真,分析SVC对风电场低电压穿越的作用。仿真结果表明,SVC可以提高风电场的低电压穿越能力。  相似文献   

4.
直驱风电机组变流器、风电机组主控装置国网电力科学研究院(原国网南京自动化研究院)研制的直驱风电机组变流器及风电机组主控装置,对提高风电机组可靠和经济运行水平具有重要作用,解决了风电场在接入网末端遭受的电压、无功波动和电网故障引起的解列等问题;对机组的控制和保护,保障了机组安全稳定运行;对接入电网的无功支撑作用,提高机组及风电场接入电网的电压稳定,增强风电场对接入网的电压支撑能力,优化风电场的无功运行水平,使风电成为电力系统中可信赖的电源。  相似文献   

5.
德国海上风电发展分析及启示   总被引:1,自引:0,他引:1  
海上风电已经成为当前风电产业发展的一个新趋势。德国作为风力发电发展较早的国家,在海上风电的发展方面有着宏伟的规划。结合德国近期投运的海上风电场情况,详细介绍了德国海上风电场的发展历程和挑战,重点分析了德国海上风电相关扶持政策、发展规划以及并网情况,并提出了德国海上风电发展给我国带来的启示。  相似文献   

6.
我国风机产业在国家政策的带动下实现快速发展,随着生产厂商的数量、规模和产能的逐年扩大,市场竞争也随之加剧。分析了当前我国几个主要风电设备厂家的产品性能、价格、业主反馈等情况,对当前2种主要机型的发电效率、维护成本和低电压穿越能力等方面进行了对比,以期对风电场风电机组选型提供参考。  相似文献   

7.
我国风电发展相关问题分析   总被引:24,自引:15,他引:9  
风电作为一种可再生能源,具有清洁、可再生、无污染的特点,也是目前最具规模化开发和商业化发展前景的新能源,对减排温室气体、保护环境和实现电力工业的可持续发展具有重要作用。本文从我国风电发展现状及风能资源入手。对未来我国风电发展的地位和作用进行了分析,介绍了我国风电技术发展现状,提出加快风电设备制造国产化、近海风电技术研发和大型风电场接入对电网的影响等问题的研究,为风力发电及风电产业的快速发展提供保障。  相似文献   

8.
经过多年的积累,龙源电力集团股份有限公司(以下简称龙源电力)确立了在新能源领域的技术及人才优势,建立了可再生能源发展研究、风电前期开发服务、风电工程咨询设计、风电工程及设备采购管理、风电场运行监控、风电场检修及技术服务、风电场备品备件管理、清洁能源机制开发服务、风电职业技术培训、风电行业公共服务平台等十大技术服务支持系统。获国家能源局授牌成立了“国家能源风电运营技术研发(实验)中心”,是五大发电集团中唯一在风电领域拥有国家级研发中心的发电企业。  相似文献   

9.
国家标准《风电场接入电力系统技术规定》(GB/T19963—2011)和能源行业标准《大型风电场并网设计规范》(NB/T31003-2011)的批准发布,标志着新的风电并网标准基本形成。风电并网标准的发布解决了风电并网标准欠缺的问题,规范了风电场并网的基本技术要求,促进了风电机组质量的提高,厘清了电场和电网井网责任,为落实《可再生能源法》规定的全额收购可再生能源奠定了基础。  相似文献   

10.
分析RCM和RCA可靠性技术方法、流程,研究在风电行业应用的可行性,结合风电场系统设备的RCM与RCA应用案例分析制定相应措施,以提高风电设备运行可靠性。  相似文献   

11.
《Telecommunications Policy》2014,38(10):914-932
This article analyzes the engagement of Japanese, Korean and Chinese participants in the development of Internet standards at IETF on the basis of four quantitative metrics: attendance, patenting, authorship and leadership. The results are strikingly divergent. Japanese involvement in Internet standardization began early and Japan was, for many years, second only to the U.S. in terms of IETF participation. Though Japanese participation has declined since the early 2000s, Japan remains a major contributor to IETF standardization. Korean involvement in IETF has always been significant, but below the levels of Japan and major European countries. Korean participation in IETF has also declined over the past decade, and has been dominated by one firm, Samsung. Though meaningful Chinese involvement in IETF did not begin until the mid-2000s, it has rapidly expanded in recent years. Today, China is a major player in numerous areas of Internet standardization in terms of three metrics (participation, patenting and leadership), and is rapidly gaining in terms of document authorship as well. Most of China׳s recent IETF involvement can be attributed to Huawei, though other Chinese firms have recently begun to increase their participation in the organization. Thus, contrary to some views that China׳s engagement with standardization is primarily one of indigenous innovation and “catching up”, China׳s experience with IETF demonstrates deliberate and effective engagement with a major Western standards-development organization on its own terms.  相似文献   

12.
快速成形技术的应用及热点分析   总被引:1,自引:0,他引:1  
基于快速成形技术的原理,展示了快速成形技术在快速模具制造、金属零件直接成形、反求工程等领域的广泛应用,总结了快速成形制造技术研究的热点,即研发新材料和新设备、提高成形精度、建立RPM的反求工程系统、建立成形技术的统一标准和扩大成形技术的应用领域。  相似文献   

13.
增强Linux系统安全性的措施   总被引:2,自引:0,他引:2  
L inux系统的安全取决于系统管理员如何来管理它。本文探讨了一系列可以增强安全性的技巧与策略 ,包括 :系统安装原则、BIOS安全、口令安全策略、设计帐户自动注销功能、文件系统和日志安全策略、使用 SSH及 TCP-WRAPPERS,隐藏系统信息、删除所有特殊帐户、关闭控制台程序、限制系统中的 SUID/ SGID程序等。本文最后向 L inux系统管理员提出了一些安全管理方面的建议  相似文献   

14.
This paper explores the idea that a sense of school subject image is a necessary feature of curriculum management and a potent force for change. The discussion centres on the view that all school subjects have an image and that if those intimately involved with the subject do not control the image then someone else does! In such circumstances the image is the product of past encounters and old euphemisms and is unlikely to hold the changed realities.The UK developments in Design and Technology education (the term Design and Technology is used to denote the school subject defined under this heading by the UK National Curriculum, 1995) have created something of an image problem which has interesting international parallels. Some of these problems are due to clearly discernible internal tensions and an ambiguous relationship with other subject areas.Through greater attention to subject image internal controversies might be acknowledged and resolved, relationships with other subject areas can be more meaningfully understood and practitioners can be helped to make sense of curriculum change.  相似文献   

15.
《Telecommunications Policy》2014,38(5-6):415-425
There is an ongoing discussion in the market which Next Generation Access (NGA) architecture best suits future needs and which investment and cost differences exist. The discussion can be subsumed as P2P vs. GPON, which is somewhat misleading as this article reveals. The discussion is driven by the fact that the high capital cost and the long asset life time of fibre mean that the technology choices made today will dominate the opportunities for telecommunication business of all market players, incumbents, competitors, content providers and business and residential users for many years in the future.The paper analyzes the cost and other differences between Fibre-to-the-Home (FTTH) access network architectures and their related different wholesale approaches by using the well-known and understood steady state approach applied in other NGA analyses in the past. In addition to the steady state analysis a dynamic cost evaluation is included taking into account the different investment behaviour of the FTTH architectures over time. The results describe investment and cost differences between architectures, incumbents and wholesale based competitive operators. The analysis has been performed for different geotypes (clusters) of decreasing population density in a representative European settlement structure.  相似文献   

16.
概括性介绍了 CIS(Corporate Identity System)的三大基本组成,并阐述了它与现代企业管理密不可分的相互联系及所处的举足轻重的地位,指出导入CIS是现代企业谋求发展的重要手段。  相似文献   

17.
企业管理水平的好坏直接影响着企业的经济效益,运用HSE管理能提高企业管理水平,HSE管理模式将健康,安全,环境三者视为一个有机的整体。HSE管理认为人的安全是第一位的,人是创造财富的原动力,是企业的最大财产,HSE管理体系强调的是“蝴蝶效应”。  相似文献   

18.
面向对象的程序设计   总被引:1,自引:0,他引:1  
用C+ + 语言阐述面向对象程序设计中封装和继承的概念以及在实际中怎样运用这些概念提高程序设计水平。  相似文献   

19.
This special section aims to investigate the interaction of global and local forces in shaping agrifood governance. It starts from the recognition that a multitude of actors and norms shape today’s agrifood system. The resulting opaqueness of the systems makes it extremely difficult to understand and explain processes and outcomes of agrifood governance. Given the sustainability challenges facing the agrifood system, improvements in our understanding of what the interaction of global and local actors and norms means on the ground are urgently needed, however. The section, therefore, analyses agrifood governance in India across a selected group of cases. It does so by employing a systematic framework emphasizing the material and ideational dimensions of power and their interaction. The section has chosen India as the setting in which to analyze this interaction due to the crucial role the food demand and supply of this rising power plays in today’s agrifood system. This article provides the special sections’ analytical framework, which uses the interplay of material and ideational dimensions of power as a focal lens. In addition, the article applies this framework to an empirical study of the political conflict around GMO foods in India, specifically the case of ‘Golden Rice’.  相似文献   

20.
In indigenous communities the nutrition transition characterized by a rapid westernization of diet and lifestyle is associated with rising prevalence of chronic disease. Field work and literature reviews from two different policy environments, Argentina (Jujuy) and Canada (Nunavut), identified factors that add to indigenous peoples’ disease risk. The analytical framework was the emerging human right to adequate food approach to policies and programmes. Indigenous peoples’ chronic disease risk tends to increase as a result of government policies that infringe on indigenous peoples’ livelihoods and territories, undermining their economic system, values and solidarity networks. Policies intended to increase food security, including food aid, may also fuel the nutrition transition. There is a need to explore further the connection between well-intended policies towards indigenous peoples and the development of chronic diseases, and to broaden the understanding of the role that different forms of discrimination play in the westernization of their lifestyles, values and food habits. Food policies that take due account of indigenous peoples’ human rights, including their right to enjoy their culture, may counteract the growth of chronic disease in these communities.  相似文献   

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