电网接纳风电能力的制约因素分析及措施

随着风电并网机组的快速增加,风电并网容量与电网接纳风电能力之间的矛盾日益突出,电网所能接纳的最大风电容量成为了风电资源利用的关键问题。通过分析制约电网接纳风电能力的各种因素,建立电网接纳风电能力的分析模型。针对各地区风电并网的具体情况,采取必要的可行的科学措施,最大限度提高电网接纳风电的能力。     

电网在调峰能力约束下接纳风电能力的估算

电网接纳风电的能力受电网调峰能力的制约。随着风电场规模的增加,风电并网运行给电网运行的压力也越来越大。通过对常规电源调峰能力分析,根据电网尖峰和低谷时刻的网供电力,建立了电网在调峰能力约束下,电网低谷时刻风电接纳容量的计算方法。利用这种方法对2015年阿勒泰地区电网风电接纳容量进行了估算,结果表明按阿勒泰地区"十二五"规划的电网结构,目前已建和在建的风电项目的规模已经接近电网接纳的极限。指出当地的清洁能源开发的安排必须与电网建设协调,避免出现"弃风"等不必要的浪费。     

基于机组调峰能力的电力系统风电接纳能力研究

为准确评估区域电力系统风电接纳能力,针对目前风电规划问题,给出一种新的计算方法。以整个时间区间上系统接纳风电电量和系统火电机组发电电量为规划指标,改变了传统风电规划主要着眼于最严峻条件下系统最大风电接纳容量的规划方法。在实际计算过程中,将系统接纳风电电量计算分两步实现,简化了模型求解过程。通过遗传算法得到任意时间区间上的系统投运机组组合,从而分析系统机组调峰能力极限。此外,将系统负荷与系统机组出力视为能量供需双方,在每个时序点上达到供需平衡,结合风资源信息计算系统可接纳风电电量及火电机组发电电量。根据实际区域电网负荷数据以及发电机组数据,经仿真计算表明,该规划方法能准确评估区域电力系统风电接纳水平,为风电装机规划提供技术参考。     

基于电力平衡的西北电网核电接纳能力分析

在分析西北电网的负荷特性及峰谷差情况的基础上,基于电力平衡计算了西北电网2020年、2025年、2030年3个水平年的核电接纳能力,分析了西北大规模风电开发对核电接纳能力的影响。结果表明:西北电网接纳核电能力与风电开发规模和进度紧密相关。在不考虑风电的情况下,西北电网2020—2030年可接纳核电能力为26 000～48 500 MW。若考虑全额收购规划风电情况下,西北电网2020年前已无核电调峰空间,2030年也仅有最大约12 000 MW的核电空间。     

电网风电接纳能力评估方法综述

对电网的风电接纳能力进行评估不仅有利于风电的规划发展,还有利于系统的调度运行。根据风电建设的不同阶段及风电接纳能力评估的不同效用,将风电接纳能力研究分为2个阶段:第一阶段是指在风电发展的初期,评估主要效用是服务于风电的规划发展,为确定电网的最大风电装机容量提供数据支撑;第二阶段是指在风电大规模并网以后,评估主要效用是服务电力系统调度运行,提高电网的风电消纳能力。分析了2个阶段的风电接纳能力评估方法,指出了目前风电接纳能力评估所存在的一些不足及相应的改进措施,并对风电接纳能力后续研究所需注意的问题提出了建议。     

基于NSGA-II的日前风电最佳接纳能力的研究

当电网接纳一定规模的风电时,继续增加风电的接纳并不能使全系统的煤耗量和污染物排放量进一步下降。针对这一问题,提出了"日前风电最佳接纳能力"的概念,构建了风电增发带来最大经济效益和环保效益时的风电最佳接纳能力的优化计算模型。将风电能够为电网节约的煤耗量和减排的污染物排放量最大以及电网接纳风电能力最大作为目标,并计及风电的波动性以及系统正负旋转备用容量约束,利用快速非支配排序的多目标遗传算法进行求解。以山西某区域电网为例,验证了文章所提模型和方法的有效性和合理性,符合节能发电调度理念。     

电网消纳大规模风电能力分析

随着风电接入电网容量的增加,调峰能力、电网输送空间和安全裕度成为制约电网消纳风电的瓶颈,为此先对电网进行调峰能力计算,得出考虑系统调峰能力约束的风电接纳能力范围,然后计算所选电网的风电场穿透功率极限用以表征风电送出问题,再对风电场并网后的电网进行稳定性分析。并对恩施电网进行实例分析,获得恩施电网的风电消纳能力,验证了该方法的可行性。     

电网对大规模风电消纳能力分析

随着风电接入电网容量的增加,调峰能力、电网输送空间和安全裕度成为制约电网消纳风电的瓶颈,为此先对电网进行调峰能力计算,得出考虑系统调峰能力约束的风电接纳能力范围,然后计算所选电网的风电场穿透功率极限用以表征风电送出问题,再对风电场并网后的电网进行稳定性分析。并对恩施电网进行实例分析,获得恩施电网的风电消纳能力,验证了该方法的可行性。     

基于调峰能力分析的电网弃风评估方法及风电弃风影响因素研究

  [目的]  由于风电出力的间歇性、随机性和反调峰特性,大规模可再生能源风电并网造成京津唐地区冬季供热季弃风现象愈加严重。  [方法]  为了能够定量研究电源调峰、联络线外送等弃风因素变化时对电网弃风的影响情况,从而准确衡量不同情形下电网对风电的接纳能力,文章从系统调峰的角度,以电热负荷平衡约束、机组出力约束为条件建立风电弃风评估模型。  [结果]  对京津唐电网弃风情况的模拟结果表明,常规电源调峰越深、联络线外送深度越小,系统接纳风电出力的空间越大;而过快的风电装机容量增长速度和较高的热电机组供热比率,会抑制风电出力,从而导致弃风。  [结论]  因此,可通过激励系统中常规电源积极主动进行调峰、控制联络线外送峰谷差和热电机组出力范围来提高系统接纳风电的能力;而根据未来规划水平,选取某一比例的风电装机容量增长速度,即可确定最佳的风电并网规模,控制弃风电量在一定水平内。     

基于枚举法的地区电网接纳风电能力评估

为准确评估地区电网的最大接纳风电容量,提出一种基于电网调峰能力约束、静态安全约束和暂态稳定约束的风电接纳评估体系。首先利用随机生产模拟技术评估风电并网后对系统备用容量的需求,进而修正传统调峰能力约束下接纳风电容量的评估;然后利用DIg SILENT平台的枚举法对各接入点可能出现的接入容量组合进行潮流计算,实现了全局搜索寻优。通过设置常见的大扰动工况进行机电暂态仿真验证,最终得到满足暂态稳定约束,即整个地区电网的最大接纳风电容量。     

大规模风电接入对宁夏电网调峰的影响研究

宁夏风电装机增长迅速,随着大规模风电的上网发电,风电有功出力的随机性、间歇性对电力系统调峰的影响日益增大.文章分析了宁夏电网网架结构、负荷以及电源特性.结合宁夏电网2012年实测数据,直观显示了宁夏电网风电出力在不同时段的波动特性,分析了大规模风电接入对宁夏电网调峰能力的影响.文章还评估了宁夏电网2013年典型运行方式下风电接纳水平.结合上述研究结果,文章提出了改善大规模风电接入后宁夏电网调峰能力的方法.     

风电接入对安庆地区电网的影响

为研究风电接入对安庆电网的影响,根据风功率的转换特性及双馈感应电机的运行特性,建立了风电场的风功率模型及双馈感应电机的动态模型,利用中国版BPA软件分析了风电接入系统后对电网静态电压稳定性、网损、短路电流及电网暂态稳定性的影响。结果表明,风电接入后电网电压满足正常运行要求,有利于网损的减小,但增大了短路点的短路电流;此外,由于风电容量较小,风电接入对电网暂态稳定性影响不大。可见,风电接入后安庆电网能安全经济运行。     

Large scale wind power integration in China: Analysis from a policy perspective

Between 2006 and 2010 the installed capacity of wind power in China has doubled and by 2010 China's cumulative installed capacity of wind power ranked the first in the world, surpassing the United States. However, the rapid expansion of installed capacity has not been matched by grid connection, and this deficiency has aroused the concern of both policy makers and scholars. Unlike most of the current studies which focus on technical strategies in China's wind power industry, this paper analyzes the problem from a policy perspective. The paper analyzes the four challenges that large scale wind power integration in China faces: the uncoordinated development between wind power capacity and power grids; the lack of suitable technical codes for wind power integration; the unclear nature of the grid companies’ responsibility for grid connection; and the inadequate economic incentives for grid enterprises. To address these problems, the paper recommends that the government: formulates policies to better coordinate the development of wind power and the planning and construction of power grids; establishes grid codes that reflect in particular the requirements to be met by users of power transmission and distribution networks; and integrates administrative intervention and economic incentive policies to stimulate the grid enterprises’ enthusiasm to absorb wind power generation.     

风电功率预测技术的应用现状及运行建议

针对我国风电开发中遇到的风电接入困难、电网调度困难等问题,对国内外解决此类问题的风电功率预测技术进行了详细的阐述。指出我国急需开发风电功率预测系统,并根据我们的风电功率预测研究经验提出了我国风电功率预测宜采用风电企业和电网共同实施的运行模式。希望对我国的风电功率预测发展起到一定的促进作用。     

Development strategies for wind power industry in Jiangsu Province,China: Based on the evaluation of resource capacity

Jiangsu Province is one of the planned strategic areas for wind power development in China, but its current development of wind power industry is not so outstanding. Since, Jiangsu would encounter little market resistance, this paper focuses on the evaluation of resource capacity for wind power development in Jiangsu Province, including the wind energy capacity, land resources capacity and power grid capacity, in order to find their supportive or restrictive effects on the development of wind power industry. The results show that the wind energy resource in Jiangsu Province are sufficient to meet the needs of the development of wind farms; the extensive mudflat in the coastal areas also provides ideal site conditions for wind farms; but the power grid capacity is insufficient for the wind power development in Jiangsu. Therefore, from the aspect of enhancing the capacity of power grid for carrying wind power and from the other aspect of combining the non-grid-connected utilization and the large-scale storage of wind power, this paper suggests some strategies to overcome the constraints of grid capacity and promoting the wind power development in Jiangsu Province.     

Demonstrating the effect of vertical and directional shear for resource mapping of wind power

The use of wind energy is growing around the world, and its growth is set to continue into the foreseeable future. Estimates of the wind speed and power are helpful to assess the potential of new sites for development and to facilitate electric grid integration studies. In the present paper, wind speed and power resource mapping analyses are performed. These resource mappings are produced on a 13 km, hourly model grid over the entire continental USA for the years of 2006–2014. The effects of the rotor equivalent wind speed (REWS) along with directional shear are investigated. The total dataset (wind speed and power) contains ≈152,000 model grid points, with each location containing ≈78,000 hourly time steps. The resource mapping and dataset are created from analysis fields, which are output from an advanced weather assimilation model. Two different methods were used to estimate the wind speed over the rotor swept area (with rotor diameter of 100 m). First, using a single wind speed at hub height (80 m) and, second, the REWS with directional shear. The demonstration study shows that in most locations the incorporation of the REWS reduces the average available wind power. In addition, the REWS technique estimates more wind power production at night and less production in the day compared with the hub height technique; potentially critical for siting new wind turbines and plants. However, the wind power estimate differences are dependent on seasonality, diurnal cycle and geographic location. More research is warranted into these effects to determine the level at which these features are observed at actual wind plants.© 2015 The Authors. Wind Energy published by John Wiley & Sons, Ltd.     

大规模风电场对电力系统稳定性影响的研究

风电机组由于其自身特点,风电机组与传统发电机组有不同的稳态和暂态特性,大规模风力发电接入电网后,电网的电压稳定性、暂态稳定性及频率稳定性都会发生变化。主要针对基于普通异步感应电机和基于双馈式感应电机风电机组的风电场对电网稳定性影响进行深入研究,使得对风电场接入电网后,给电网稳定性带来的问题有更全面、更深入的认识,有利于我国风力发电快速、健康发展。     

Current situation and development of wind power in China

The current development of wind power in China was presented in this paper. Many regions such as Xinjiang Uygur Autonomous Region, Inner Mongolia Autonomous Region and southeast coastal region, etc. in China have abundant wind energy resource. At the same time, the utilization of wind power in China has been developing quickly and its prospect is promising in spite of many some obstacles. With the implementation of the Renewable Energy Law, some previous obstacles have been or are being eliminated. Much investment and many enterprises start to enter this field. In spite of this, there still exist some financial and technological obstacles. One of the technological obstacles is the stability of local power grid owing to the increasing proportion of the wind power capacity. Because the centralized development mode of wind power was adopted, the quick fluctuation of wind speed will influence the voltage and frequency stability of local power grid. In addition, large wind farm has little dispatching ability because of the uncontrollability, randomness and fluctuation of natural incoming wind. To erase these obstacles, a novel hybrid power system combining wind farm and small gas turbine power plants is discussed.     

风电场并网对电力系统稳定性影响

稳定性是影响大电网区域互联的关键性因素。随着风电场规模的不断扩大,其接入电网会对电力系统的稳定性带来一定影响。介绍了风力发电系统建模方法及风力发电机模型,分析了风电场并网对电力系统无功电压、潮流分布、电能质量、系统短路容量、调峰调频等方面的影响,并对电力发电技术发展新动向作了展望。