解析风电场对电网继电保护的影响

随着风电场机组容量的逐年加大,大规模的风电接入对电力系统的电能质量产生了极大的影响,由于风能具有不可控制性和随机性,当风能增大时向系统提供的短路电流也越大,所以风电场对电网继电保护的影响很重要。本文从风电场对电网继电保护的影响角度进行分析论证,对风电场的保护作用进行分析。     

40个风电场获批接入新疆电网

2012年1月,先后有21个风电场获批接入新疆电网,总装机容量103．95万kW,按照计划,年内还将有近20个风电场获批接入新疆电网。     

上海东海大桥海上风电场规划建设关键技术研究

通过对上海东海大桥海上风电场的选址、风电场升压方式、基础选型设计、桩基试验、基础施工、风机安装等技术问题的研究和实践,提出了海上风电场选址原则、接入电网方式、具有防撞能力的高桩混凝土承台基础形式、风机基础结构分析方法、桩的承载力试验手段、高桩承台施工和风机整体吊装方案等,为海上风电场规划建设提供借鉴。     

海岸滩涂风电场建设工程保障策略探讨

根据海岸滩涂和浅水海域风电场建设及运行维护工程保障的需求,提出了一系列的工程保障方案,主要包括:适应于潮上带滩涂风电场的系列道路构筑方案、适应于潮间带滩涂风电场的承压浮箱及浮箱栈桥保障方案、适应于潮下带5 m以上水深风电场的浅吃水自升式海上风电场工程平台以及风电场运行维护期间的两栖进入方案,并对这些方案的适应性、可行性及技术要点进行了探讨。提出的系列工程保障方案针对潮上带、潮间带至潮下带不同滩涂区域对施工工程技术的不同要求,以系列技术保障措施分段保障,较好地解决了海岸滩涂及浅水海域风电场建设的工程保障问题。     

风电场动态无功补偿方案探究

本文简要介绍了风电场的动态无功补偿设备,对几种风电场无功补偿方案进行了研究,着重分析了SVC静止无功补偿方案中的不足和改进,对提高风电场动态无功补偿能力提出了一些建议和看法。     

风电场次同步振荡等值建模方法研究

风电场中风机数量大并且处于不同的运行风速,建立包含每台风机详细的次同步振荡研究模型非常复杂,而且应用该模型进行次同步振荡研究计算耗时长。因此,需要建立保留风电场与接入系统相互作用的次同步振荡特性的风电场等值模型,简化次同步振荡研究的复杂程度。计及风机不同运行风速区间的不同控制策略对次同步振荡模式的影响,采用基于风速指标K-means算法聚类风机,考虑各台风电机组出线端的电流幅值和相位不同的影响,提出基于功率等值的集电系统简化建模方法,在PSCAD/EMTDC中搭建相关风电场仿真模型,并对等值前后次同步振荡模态进行了对比,用以验证该等值方法的合理性。     

风电场接入对崇明电网的影响分析

随着更多风电场接入电网和风电场的规模不断扩大,风电特性对电网的负面影响越来越显著。深入研究风电场接入对电网电压、频率、稳定性等特性的影响,保证电力系统稳定发展显得尤为重要。笔者结合崇明电网情况详细介绍了异步风力发电接入系统的组成和风电场接入对崇明电网的影响以及其解决措施。     

风电场升压变电站综合自动化配置

随着我国智能电网的不断迅猛发展,我国现在很多城市虽然已经建立了智能电网系统,但是,我国风电场发电应用的还比较的少,尤其对风电场升压变电站综合自动化配置使用的更加少。因此,研究风电场升压变电站综合自动化配置具有非常重大的现实意义。本文分别对风电场和升压变电站进行了详细的阐述说明,最后重点介绍了变电站数字化和自动化的系统综合配置。     

基于GIS分析的风电场宏观选址方法研究与应用

随着全球环境问题日益突出,可再生能源的利用越来越受到人们的关注。其中,风能是一种具有广泛应用前景的清洁能源,而风电场的选址是风能利用的重要环节。该研究以GIS技术为基础,探索风电场宏观选址方法,旨在提高风电场选址的效率和可靠性。该研究首先对风电场宏观选址的影响因素进行总结,其次,利用GIS技术对选址区域地形以及地类因素进行评估,建立风电场宏观选址模型。最后,该研究以河北某地区为例,应用所提出的风电场宏观选址方法进行了实证分析。研究结果表明,该方法能够有效地筛选最适宜建设风电场的区域,具有很好的实用性和可操作性。同时,该方法还有一定的普适性,可以为其他地区的风电场选址提供参考,提升风电场宏观选址总体规划效率。     

一种风速预测方法的探讨

风速预测对提高电网的稳定性及降低运行成本具有重要意义,但风速具有较大的波动性,导致预测精度不高.针对这种情况,利用灰色系统理论GM(1,1)模型的基本原理,依据某风电场实测数据,建立了风速预测的物理模型,对该风电场的风速进行了提前一小时预测.实验表明,其预测平均绝对百分比误差为13%,这说明基于灰色理论的风速预测模型是有效的。     

含不同机组风电场低电压穿越能力仿真研究

在PSCAD/EMTDC仿真环境下建立双馈风力发电场及恒速恒频风力发电场交流并网仿真模型,通过交流系统三相短路故障仿真,研究对比2种不同风力发电机组的低电压穿越能力。仿真得出恒速恒频风力发电机组避免飞车的极限切除时间,故障持续时间小于极限切除时间便可维持恒速恒频风力发电机组的稳定不脱网运行。通过在不同点设置短路故障对比得出,故障点距离风电场电气距离越远,风电场低电压穿越能力越强。     

风电场有功功率控制综述

由于风电具有随机性、波动性和反调峰特性,高比例的风电并入电网会对电力系统的稳定性和安全性造成很大的冲击,因此有必要对风电场有功功率输出进行控制,减少风电功率的波动性,提高输出功率的平滑性;同时,随着装机容量的不断增加,造成大量的弃风现象,风电场的控制模式由传统的最大功率点跟踪（maximum power point tracking,MPPT）模式向限功率控制模式转变。基于弃风限电以及风电并网的控制要求这2个背景,分析了控制风电场有功功率的必要性,从单机功率控制和场站级功率控制2个层面出发,以场站级功率控制为侧重点,归纳总结了当前风电有功功率控制的研究现状,总结出不同控制方式的控制特点及不足之处,并对其研究方向进行了展望。     

Perspectives of China’s Wind Energy Development

Wind energy is a kind of clean renewable energy, which is also relatively mature in technology, with large-scale development conditions and prospect for the commercialization. Wind energy’s development and utilization is an important measure to increase energy supply, adjust energy structure, ensure energy security, protect the ecological environment, reduce greenhouse gas emission and build a harmonious society. Wind energy is a kind of clean renewable energy, which is also relatively mature in technology, with large-scale development conditions and prospect for the commercialization. The development of wind energy is a systematic project, involving policy, law, technology, economy, society, environment, education and other aspects. The relationship among all the aspects should be well treated and coordinated. This paper has discussed the following relationships which should be well coordinated: relationship between wind resources and wind energy development, relationship between the wind turbine generator system and the components, relationship between wind energy technology and wind energy industry, relationship between off-grid wind power and grid-connected wind power, relationship between wind farm and the power grid, relationship between onshore wind power and offshore wind power, relationship between wind energy and other energies, relationship between technology introduction and self-innovation, relationship among foreign-funded, joint ventured and domestic-funded enterprises and relationship between the government guidance and the market regulation, as well as giving out some suggestions.     

Offshore wind farm with centralised power conversion and DC interconnection

The study of a hypothetical large offshore wind farm based on centralised power conversion and interconnected to the grid using a multiterminal parallel high voltage direct current (HVDC) link is presented. The 300 MW wind farm consists of 60 squirrel-cage based 5 MW generators connected to a common DC bus using ten voltage source converters (VSCs). The transmission system converters provide variable speed generator control, and therefore individual converters are not required for each wind generator, implying savings in wind farm costs. The paper studies the technical and economical benefits of the proposed topology, as well as the selection of the main components. A detailed analysis of the control circuits for both generator and grid facing converters, with respect to primary control functions, is also given. PSCAD/EMTDC simulation of the proposed concept is presented for realistic wind signals. The results confirm operation at an average optimum coefficient of performance at each respective generator group, as well as satisfactory stability even for severe wind speed changes. The proposed concept reduces the costs associated with DC interconnection and may simplify integration of large offshore wind farms at substantial distances.     

电动汽车参与风电场输出功率波动平抑方法研究

由于风电固有的随机性与间歇性,使得风电场输出功率往往具有较大的波动。然而考虑到储能装置的昂贵成本,单独为风电场配置储能装置不利于其经济运行。为此,文中针对考虑电动汽车参与的风电场输出功率波动平抑方法进行了研究。根据国家标准中风电“有功功率变化”的要求,通过爬坡率概念来描述风电场输出功率变化率。采用鲁棒优化的方法处理风电出力的不确定性,建立风电机组和电动汽车协调控制的双层优化模型：上层模型决策者是风电场,以风电场售电收益最大化为目标函数;下层模型决策者是电动汽车车主,以电动汽车电费支出成本最小化为目标函数。通过线性规划对偶定理和Karush-KuhnTucker（KKT）最优性条件将此鲁棒优化模型转化为混合整数线性规划问题进行求解。最后,通过仿真结果验证了所提模型和方法的有效性。     

Network-based optimization techniques for wind farm location decisions

This study aims to find appropriate locations for wind farms that can maximize the overall energy output while controlling the effects of wind speed variability. High wind speeds are required to obtain the maximum possible power output of a wind farm. However, balancing the wind energy supplies over time by selecting diverse locations is necessary. These issues are addressed using network-based models. Hence, actual wind speed data are utilized to demonstrate the advantages of the proposed approach.     

考虑储能寿命和参与调频服务的风储联合运行优化策略

储能系统与风电场联合运行,不但可跟踪风电场计划出力,还可参与电网的辅助服务。以风储联合运行的总收益最大为目标,考虑储能系统跟踪风电计划出力与参与电网二次调频服务,建立风储联合运行的优化模型。该模型重点考虑了计及不同荷电状态下的储能寿命损耗和储能参与调频时向上调频电量与向下调频电量的平衡。基于实际风电场运行数据设计算例并进行仿真分析,结果表明,考虑储能寿命损耗和储能调频电量水平,不仅可以合理衡量储能参与各项服务所带来的收益,还可以充分发挥储能的作用并提高风储联合的收益。     

风电出力时序特性及其对省级电网的影响

随着风电的快速发展,大规模风电接入给省级电网调度运行带来一系列问题。首先,对风电出力的重要特性指标及其对电网运行的具体影响进行阐述分析;其次,为了更好地量化计算风电出力不同时序特性对电网的影响,建立一套从多角度反映风电时序特性对电网调度运行影响的特征指标,然后根据多个风电场群的真实出力数据,分别从不同时空尺度分析风电出力时间序列的分布特性、波动性及相关性;最后,基于某省级电网数据及其并网风电出力数据,研究分析风电时序特性对电网调频、调峰等影响,为省级电网风电优化调度提供参考。     

漂浮式风电场的基础形式和发展趋势

阐述了海上风电场的分类,并对漂浮式风电场风电机组的浮式基础作了详细的介绍。随着风电开发技术的成熟,风机容量大型化、垂直轴风机的应用及建立非并网风电多元化应用系统将是以后漂浮式风电场发展的趋势。     

A hybrid extended pattern search/genetic algorithm for multi-stage wind farm optimization

This purpose of this work is to explore means of optimizing multi-stage wind farms using two derivative-free optimization methods: a hybrid Extended Pattern Search/Genetic Algorithm (capitalizing on the benefits of each), and a multi-objective Extended Pattern Search. Large onshore wind farms are often installed in discrete phases, with smaller sub-farms being installed and becoming operational in succession, creating the completed large wind farm in a piece-wise fashion over multiple years. Multi-stage wind farms present a complex and relevant optimization challenge in that in addition to accounting for the site-specific objectives of a wind farm (such as power development and profit), optimization of both the discrete sub-farms and the completed farm must be jointly considered. Two different problem formulations are explored: the first uses the optimal layout of a complete farm and then systematically “removes” turbines to create smaller sub-farms; the second uses a weighted multi-objective optimization over sequential, adjacent land that concurrently optimizes each sub-farm and the complete farm. For both problem formulations, two wind test cases are considered for both a square and a rectangular field: a constant wind speed from a predominant wind direction, and a multidirectional test case with three wind speeds and a defined probability of occurrence for each. The exploration of these resulting layouts indicates the value of the advanced multi-objective EPS and the hybrid EPS/GA, and gives insight into how to approach optimizing both completed wind farms and sub-farm stages. The behavior exhibited in these tests cases suggests strategies that can be employed by wind farm developers to facilitate predictable, optimal performance of multi-stage wind farms throughout their useful life.