船舶碰撞对海上风电机组结构载荷的影响研究

当运维船向海上风电机组靠泊时,会对风电机组产生碰撞作用,进而对风电机组的基础和结构载荷产生影响.本文选取了一台4MW海上风电机组,对其在运维船碰撞时的结构载荷变化进行了实验研究.在实验现场测试了轮毂高度风速、波浪和海流参数,并将这些参数引入风电机组的动力学模型进行仿真分析,从而获得了风电机组的载荷变化的仿真结果.最后将...     

矿用干式变压器保护设计缺陷的分析及处理

针对KBSGZY---10/630---1.14移动干式变压器保护在设计中的缺陷进行分析研究,并根据现场实际工作经验提出了解决方案,为干式变压器在实际生产中故障排除提供帮助,为干式变压器设计和安全运行提供了保障.     

基于温度场仿真的干式变压器散热设计

随着国家经济的快速发展,变压器的应用已涉及各个领域,干式变压器因其安全、环保、免维护等优点,而被广泛应用。干式变压器的应用环境千差万别,一旦发生故障,将会引起大范围的停电,给工农业生产和人们生活带来诸多不利,因此,对干式变压器的可靠性要求也随之提升。综合分析各类干式变压器的故障原因,有很大一部分故障原因是干式变压器的局部过热而引发的绝缘失效。在故障发生的前后一段时间内,温度场会随着故障的发生而产生不同的变化。为了解温度场的变化,利用有限元分析,建立干式变压器的三维模型,并对模型的电磁场、温度场和流体场进行计算,得到干式变压器的温度场分布。通过干式变压器的温度场分析出干式变压器易存在过热点的位置,对该位置进行故障模拟,获取变压器的温度场分布变化,再根据分布变化对影响干式变压器的散热的出风口位置进行优化模拟。结果表明,模拟结果与试验结果吻合,通风口位置设置会影响产品的散热效果。     

光伏发电用干式变压器关键技术研究

干式变压器作为光伏电站的关键组成部分,具有结构紧凑、易于安装维护、质量体积小、工作效率高、能源损耗少等特点,可以将光伏发电产生的电压提高到电网需要的电压值,对于光伏电站并网系统的电能质量有着至关重要的影响。文章从光伏电站干式变压器使用背景入手,在分析了光伏逆变电路特征的基础上,探讨了干式变压器关键技术研究,从源头上保证光伏电站的运行质量,推动了电力行业健康发展。     

软弱地基中海上风电大直径缩径单桩基础结构设计研究

基于真实设计参数和环境荷载,通过PLAXIS Monopile Designer和SACS软件实现某风场机位的缩径单桩优化设计,并进行结构极限强度、结构变形、自振频率和疲劳分析计算。相比于相同上部尺寸的常规单桩基础,缩径单桩具有较大的泥面转角和水平位移,较低的竖向位移和自振频率,计算结果验证了缩径单桩基础方案的可行性,并可实现节省10.9%的用钢量。     

大规模海上风电高电压穿越研究进展与展望

海上风电因其风速高、风力稳定、对环境影响小、发电量大等特点成为可再生能源的发展重心.因海上传输线路产生容性无功,风电场容易面临高电压穿越问题.梳理了当前国内外海上风电机组高电压穿越的发展历程,并以当前主流机型双馈风机系统为研究对象,从风机控制器控制策略、电压源换流器控制策略、增加补偿装置以及增加组合保护电路方面,对目前...     

干式变压器的应用

随着#8机炉的建成、投产、安全运行，我厂实现了对干式变压器安全有效、地使用。21世纪的配电变压器将属于性能优越、低噪声、节能、维护工作量小的树脂绝缘干式变压器。因此说，我厂积极推广使用干式变压器是顺应了配电装置的发展方向。     

Pricing offshore wind power

Offshore wind offers a very large clean power resource, but electricity from the first US offshore wind contracts is costlier than current regional wholesale electricity prices. To better understand the factors that drive these costs, we develop a pro-forma cash flow model to calculate two results: the levelized cost of energy, and the breakeven price required for financial viability. We then determine input values based on our analysis of capital markets and of 35 operating and planned projects in Europe, China, and the United States. The model is run for a range of inputs appropriate to US policies, electricity markets, and capital markets to assess how changes in policy incentives, project inputs, and financial structure affect the breakeven price of offshore wind power. The model and documentation are made publicly available.     

基于防护技术的海上风电变流器高可靠性优化结构设计

为了提高海上风电变流器设备或系统的可靠性,对海上风电变流器设备的防护技术进行了详细的分析。针对海上风电变流器自身特点,从密封性、材料、绝缘等方面进行优化设计。     

Understanding public responses to offshore wind power

This paper is about understanding the role and importance of public responses to offshore wind power. It builds on a framework for understanding social acceptance and opposition to onshore turbines, and reviews the emerging research on offshore wind. While less is known about how people will respond to offshore than onshore wind, there is now an emerging body of research. From this literature, several common factors which influence responses have emerged and are discussed here: the (continued) role of visual impact; place attachment to the local area; lack of tangible benefits; relationships with developers and outsiders; and the role of the planning and decision-making systems. The paper argues that, as with onshore developments, the public should be included in decision-making about offshore wind farms, and that they have a key role which should not be underestimated. The paper concludes with some thoughts about the means to involve people and how effected communities might be effectively acknowledged, identified and engaged.     

The offshore trend: Structural changes in the wind power sector

In recent years, the wind power sector has begun to move offshore, i.e. to use space and good wind speeds on the open sea for large scale electricity generation. Offshore wind power, however, is not just technologically challenging but also a capital intensive and risky business that requires particular financial and organizational resources not all potential investors might have. We therefore address the question, what impact offshore wind power may have on ownership and organizational structures in the wind power sector. We compare on- and offshore wind park ownership in Denmark, the UK and Germany. The analysis shows that offshore wind power in all three countries is dominated by large firms, many of which are from the electricity sector. In Denmark and the UK, also investors from the gas and oil industry play an important role in the offshore wind business. This development represents a major shift for countries such as Germany and Denmark, in which the wind power sector has grown and matured on the basis of investments by individuals, farmers, cooperatives and independent project developers. The structural changes by which offshore wind power is accompanied have consequences for turbine manufacturers, project developers, investors, associations and policy makers in the field.     

大型海上风电场无功配置研究

海上风电场通过高压海缆接入陆上电网。长距离高压海缆的充电功率使得海上风电场与内陆风电场的无功规划有较大不同。文章首先分析了海上风电场集电系统与汇集系统的无功消耗和充电功率特点,考虑电压调整和无功就地平衡的要求,建立了海上风电场的无功配置的一般计算流程。对于不同容量、不同离岸距离的海上风电场给出了典型的无功容量和地点的配置方案,为规划提供了参考。     

The economics of offshore wind

This paper presents an overview of the main issues associated with the economics of offshore wind. Investment in offshore wind systems has been growing rapidly throughout Europe, and the technology will be essential in meeting EU targets for renewable energy in 2020. Offshore wind suffers from high installation and connection costs, however, making government support essential. We review various support policies used in Europe, concluding that tender-based feed-in tariff schemes, as used in Denmark, may be best for providing adequate support while minimising developers’ rents. It may prove economic to build an international offshore grid connecting wind farms belonging to different countries that are sited close to each other.     

Assessment of imbalance settlement exemptions for offshore wind power generation in Belgium

This article deals with a specific support mechanism exempting offshore wind power generators partially from their balancing responsibilities by means of a tolerance margin. This specific support mechanism was enforced in Belgium as from 2009 and is defended by its proponents in view of the lower power output predictability at offshore locations. Although policies accommodating offshore developments may be seen as important to tap better wind resources, this contribution stresses the importance of full balancing responsibility for variable renewables. After a detailed evaluation of the support mechanism and its impact on the balancing costs for wind power generators, the use of current applied production support mechanisms is recommended. These can be used to acquire the same financial effect without increasing market complexity and harming the operation of the balancing market. The first part of the study deals with the specific implementation of the tolerance margin in the Belgian context. Secondly, its underlying motivation is quantitatively assessed, namely the relatively higher offshore prediction errors. Finally, the total offshore subsidy resulting from the measure is determined. Expressed in €/MWh, this subsidy is currently determined at €1.4–1.7/MWh, which represents the required increase of production support in order to replace the regulation.     

海上风电发展趋势及关键技术研究

介绍了国内外海上风电发展现状,阐述了海上风电存在的关键技术问题,探讨了我国发展海上风电所面临的问题及应采取的对策,可为未来大型海上风电场建设提供借鉴.     

Assessing ecological risks of offshore wind power on Kattegat cod

Offshore wind power is expanding with particular development plans in the Baltic and the North Sea. To reassure an environmentally acceptable development, regulatory authorities need to make informed decisions even when evidence and experience are scarce. In this study Ecological Risk Assessment (ERA) has been applied on a wind farm project in Kattegat, proposed within a spawning ground for the Kattegat cod, a threatened population of Atlantic cod (Gadus morhua L.). Six stressors with potential impacts on cod and related to wind farms were investigated. Three of them – extreme noise from pile driving, noise from vessels, and disturbances due to cable-trenching – are related to the construction phase, while lubricant spills and noise from turbines together with electric fields from cables are related to the operation phase. The ecological risk was derived from the combined likelihood and magnitude of potential adverse effects from stressors to the cod population using a weight-of-evidence (WOE) ranking procedure. Available evidence was evaluated based on its reliability, and contradictory arguments were balanced against each other using evidence maps. The option of performing hazardous construction events (e.g. pile-driving) outside biologically sensitive periods was incorporated in the assessment. It was shown that the construction of the wind farm poses a high risk to cod, as defined by the ranked and combined likelihoods and magnitudes of adverse effects. However by avoiding particular construction events during the cod recruitment period ecological risks can be significantly reduced. Specifically for this case, ecological risks are reduced from high to low by avoiding pile-driving from December through June, which confirms previous indications that pile-driving is the most ecologically hazardous activity of offshore wind power development. Additional risk reduction is achieved by avoiding cable trenching from January through May. The study thus illustrates the effectiveness of time-planning for risk reduction. Importantly, the study illustrates how combined ERA and WOE methods can be valuable for handling uncertainties of environmental impacts within offshore industrial development.