桁架式支撑结构海上风电机组研究

本文基于国际能源署(IEA)课题30"海上风电机组动态学仿真软件和模型的比较"项目第一阶段桁架式支撑结构的海上风电机组仿真结果,针对海上风电模型复杂的特点,给出桁架式支撑结构细节,研究用BladedV3.80建立桁架式支撑结构的海上风电机组模型。与其他软件建立的模型比较质量和模态,验证海上风电机组的模型。     

海上大型风电机组传动链研究

在风力发电系统的研究和开发中,由于受气象环境、地理条件的限制,无法对风力发电系统进行以全生命周期作为评价的实验测试,尤其是动力传输系统。传动链在风电机组的传动系统中起到传递叶轮扭矩的作用。本文介绍了风电机组用于海上风电情况下,对于传动链设计的可能布局和轴承配置形式。同时,对于海上风电的应用环境,传动链设计应着重于提高机组的可靠性,采用冗余设计,并允许采用高叶尖速带来的可能益处。     

海上风电机组发展趋势分析

本文追述了海上风电机组的发展历程,分析了世界各主要风电机组生产厂家正在研制的海上风电机组的技术路线,提出了海上风电机组今后发展的主要趋势。     

海上风电机组基础施工过程中噪音消减方法浅析

结合欧洲海上风电场建设经验,本文介绍了多种常见降低噪音的方法。通过工程实例,结合海上风电机组钢结构基础施工特点,采用多种方法相结合进行噪音消减,最大程度上降低海上风电机组钢结构基础施工对海洋生物的危害。     

大型海上风电机组变桨距PID控制策略研究

文章针对大型海上风机的叶片具有较大惯性的问题,分析了传统变桨距PI控制器的不足,从而设计出带有超前环节的变桨距PID控制器,其能改善因惯性较大而导致的不良控制效果,并通过典型工况的仿真计算及性能分析,表明PID控制器的整体性能优于PI控制器,不仅具有稳定风轮转速、减轻风机振动的优点,还降低了风机的极限载荷水平,从而在保证安全性的基础上降低了机组成本。     

海上风电机组辅助监控系统方案设计

  [目的]  考虑海上风电场生产监控与运营管理的需求,分析海上风电机组辅助监控系统总体设计、功能要求、子系统要求。  [方法]  整合风机状态监测系统(含振动在线状态监测系统、风机基础监测系统、螺栓载荷在线监测系统、桨叶状态监测系统、发电机绝缘电阻自动监测系统、雷电远程监测系统、齿轮箱润滑油质在线监测系统、箱变运行状态监测系统)、视频监控系统、风机IP电话系统、扩展功能等,实现风机动力设备、环境、安防的统一监控。  [结果]  该系统结合多参数信息融合,实现电气及机械特征量的风机故障诊断,为广东省海上风电大数据中心的风机性能比较提供支撑。  [结论]  辅助监控系统方案可实现预防性的运营维护,使风电场智能化监控和故障早期预警成为可能。     

海上风电机组电气火灾风险分析及其防护

为寻找有效控制海上风电机组火灾风险的技术方案,分析了海上风电机组火灾风险的特点和类型,指出了海上风电机组电气火灾防护的必要性。根据相关规范的要求和应用特点,进行了海上风电机组电气火灾防护系统的选型和设计,采用高压二氧化碳自动灭火系统,并开展了基于PLC的火灾防护控制器的开发。所开发的海上风电机组电气火灾防护系统针对重点火灾风险区域进行防护,可有效避免海上风电机组电气火灾事故造成的巨大经济损失,以较低的成本取得了较高的安全收益,具有较好的经济性和可行性。     

8MW海上风电机组的施工和安装技术介绍

随着海上风电的迅速发展,海上风电机组的单机容量越来越大,需要更加先进、安全、经济的施工安装技术和设备,施工效率也需要更加高效.结合国内首台完全自主开发的8 MW直驱式海上风电机组的实际施工情况,从安装工程概况、风电机组参数、安装船情况、安装船施工能力、整体施工工艺几方面对大容量海上风电机组的安装技术进行了介绍,以期为类...     

海上风电机组防盐雾措施探讨

海上风电机组最难处理的技术问题之一就是盐雾对发电机组的影响。本文重点讨论了机舱内部防盐雾的措施,提出装有空气过滤装置的防盐雾方法和水冷加空调的新方案,较好地解决了机舱内部盐雾对机组的影响问题。     

海上风力发电机组基础的选择

介绍了海上风力发电的发展现状,结合海上采油平台形式,对海上风电机组采用的基础定义、基础类型及其选择进行了介绍。     

近海风力机动力特性分析方法的研究

海上风力发电具有广阔的应用前景,因此要大力发展海上风机。以单桩式近海风力发电机为例,利用风机正向设计专业软件SAMCEF for Wind Turbine,对风机结构进行模态分析,得到结构的振动特性。由分析结果可知,风机整体振型复杂,不同构件振型变化较大,构件之间有连带作用;在系统的各阶振型中,每个构件的应变能贡献值各不相同,在设计风机时应避开结构的共振区域,以免造成风机结构的破坏。     

新型铰接式海上风力机动力响应分析

文章针对75 m水深,开发了一种新型铰接式基础海上风力机,考虑到风浪流的联合作用,分析了其在发电海况和极限海况下的动力响应。基于叶素动量理论计算了风力机叶片气动载荷;基于经验公式计算了塔架风压载荷;基于三维势流理论计算了铰接式基础的水动力特性;考虑基础运动及波高引起的瞬时湿表面的变化及铰接点的结构阻尼,同时考虑海流力,编写程序计算风力机的时域动力响应特性。计算结果表明,铰接式海上风力机具有良好的运动性能,满足发电海况下正常发电的需求以及极限海况下结构自存的安全要求。     

Simplified fatigue load assessment in offshore wind turbine structural analysis

The estimation of fatigue lifetime for an offshore wind turbine support structure requires a large number of time‐domain simulations. It is an important question whether it is possible to reduce the number of load cases while retaining a high level of accuracy of the results. We present a novel method for simplified fatigue load assessments based on statistical regression models that estimate fatigue damage during power production. The main idea is to predict the total fatigue damage only and not also the individual damage values for each load case. We demonstrate the method for a jacket‐type support structure. Reducing the number of simulated load cases from 21 to 3, the total fatigue damage estimate exhibited a maximum error of about 6% compared with the complete assessment. As a consequence, a significant amount of simulation time can be saved, in the order of a factor of seven. This quick fatigue assessment is especially interesting in the application of structural optimization, with a large number of iterations. Copyright © 2015 John Wiley & Sons, Ltd.     

海上风力机的数值模拟

针对海上风力机运行的特点,根据NRELS809翼型数据,建立了水平轴风力机的整体模型。采用空气和水的两相流模型模拟海上工况,对模型进行数值计算,得到叶片绕流的速度分布和压力分布,并对两相流和单相流的变化情况进行了对比,最后对塔架的压力分布进行计算说明。研究结果表明:在两相流工况下,风轮叶片具有较高的功率系数,但该工况对叶片的强度、材料要求较高;气流流过叶片后均存在速度亏损,并在1倍风轮半径处趋于稳定;风轮对塔架的压力分布产生一定影响。     

海上三桩风机基础简化及荷载响应对比分析

三桩基础(Tripile Foundation)是一种新型的海上风机支撑结构,广泛适用于地质相对复杂、水位较深的风场。文章理论分析了海上风机基础桩—土相互作用简化方法,运用ANSYS建立3维有限元模型,考虑不同种地基约束简化方法,对单机3 MW三桩基础在不同方向极限荷载作用下进行数值分析。结果表明:三根桩非平均承担结构荷载,不同方向荷载作用结构响应呈规律性变化,荷载为0°方向时结构位移最大,荷载为20~30°方向时结构应力最大。实际工程计算时,需运用不同简化模型进行对比校核,重点考虑基础单桩主受拉、单桩主受压及20~30°荷载方向。     

多海况下海上风力机组基础载荷特性分析

在相同的风况下设计了5组不同的波浪、海流,作为海上风力机的外界环境扰动。依据IEC标准,设计海上风力机等效疲劳载荷计算工况,并以某3.0 MW海上风力机组为对象进行极限载荷及等效疲劳载荷计算,在5组不同风浪联合作用下,通过对载荷对比、频谱分析及基础载荷的模态分析表明,波浪及海流对基础共振有一定影响。该研究为海上风力发电机组基础设计提供了可靠依据。     

Seismic fragility analysis of 5 MW offshore wind turbine

Considering nonlinear soil–pile interaction, seismic fragility analysis of offshore wind turbine was performed. Interface between ground soils and piles were modeled as nonlinear spring elements. Ground excitation time histories were applied to spring boundaries. Two methods of applying ground motion were compared. Different time histories from free field analysis were applied to each boundary in the first loading plan (A). They were compared with the second loading plan (B) in which the same ground motion is applied to all boundaries. Critical displacement for wind turbine was proposed by using push-over analysis. Both the stress based and the displacement based fragility curves were obtained using dynamic responses for different peak ground accelerations (PGAs). In numerical example, it was shown that seismic responses from loading plan A are bigger than from plan B. It seems that the bigger ground motion at surface can cause less response at wind turbine due to phase difference between ground motions at various soil layers. Finally, it can be concluded that layer by layer ground motions from free field analysis should be used in seismic design of offshore wind turbine.     

Reliability-based layout optimization in offshore wind energy systems

Existing methods for optimizing wind array layouts typically use power or cost objectives and rarely consider reliability-based objectives. Component and system failure rates, however, are dependent on location-specific wind conditions, are influenced by array layout and wake interactions, and have a direct and significant impact on capital costs, operational costs, and power production. Although wind power plant models exist that calculate wind loads with sufficient resolution to capture component loading dynamics from wind conditions, they are computationally expensive and thus not suitable for research applications requiring many evaluations, particularly optimization. This study describes the development of computationally efficient, reliability-based layout optimization methods, enabling us to explore the relationship between component reliability and layout optimization. These methods include the surrogate modeling of the planet bearing life based on varying wind conditions simulated in FAST.Farm and the formulation of reliability-based objectives based on failure cost and power production models. Through demonstration of this method, we explore how wind conditions, objective functions, and capacity density influence reliability-based layout optimization. Results indicate that considering reliability alongside power production can reduce failure costs associated with replacement costs and downtime whilemaintaining or improving power production. Our conclusions highlight the opportunity for wind power plant developers to integrate reliability and operational expenditures alongside performance and capital expenditure objectives in plant design and development to improve plant performance and costs.     

Multi-criteria assessment of offshore wind turbine support structures

Wind power, especially offshore, is considered one of the most promising sources of ‘clean’ energy towards meeting the EU and UK targets for 2020 and 2050. Deployment of wind turbines in constantly increasing water depths has raised the issue of the appropriate selection of the most suitable support structures’ options. Based on experience and technology from the offshore oil and gas industry, several different configurations have been proposed for different operational conditions. This paper presents a methodology for the systematic assessment of the selection of the most preferable, among the different configurations, support structures for offshore wind turbines, taking into consideration several attributes through the widely used multi-criteria decision making method TOPSIS (Technique for Order Preference by Similarity to Ideal Solution) for the benchmarking of those candidate options. An application comparing a monopile, a tripod and a jacket, for a reference 5.5 MW wind turbine and a reference depth of 40 m, considering multiple engineering, economical and environmental attributes, will illustrate the effectiveness of the proposed methodology.