应用于平抑风功率的燃氢燃气轮机储能系统控制策略研究

储能技术可用于提高风电并网能力,因此其储能系统及控制策略成为研究热点。提出将燃氢燃气轮机作为储能系统主要部分,低通滤波器结合模糊控制作为其平抑风功率的控制策略。通过设定储氢罐容量,对15台1.5 MW风机的历史风功率数据进行了处理。结果表明：低通滤波器结合模糊控制能有效平抑风功率至限制值,实现平抑指标,并得到储氢罐容量的设置限制;可实现储能时燃气轮机不工作,耗能时燃气轮机工作,当储氢罐容量为0.017 m³时,燃气轮机输出功率为0.1 MW。在将燃气轮机作为平抑风功率的储能系统时,需将燃气轮机的启停控制作为今后的研究重点。     

储能设备对孤立风力发电系统的影响

采用序贯蒙特卡罗法对含有储能设备的风/柴孤立发电系统进行充裕度评估。针对样例系统,在发电系统强迫停运率、储能设备容量以及峰值负荷取值不同的情况下,计算发电系统的充裕度指标;研究储能设备对孤立发电系统充裕度的影响,并对产生影响的原因进行分析。结果表明,加入储能设备可改善发电系统的充裕度,提高系统的供电可靠性水平,减少风力发电机组输出功率波动对系统的影响。分析方法和结果可为储能设备在风力发电系统中的应用和储能设备容量的选择等方面提供参考。     

世界促进风电产业发展最新动向

近年来可再生能源发电发展迅速,其中风力发电表现尤为突出.在一些风电先行国家的推动下,风电机组大型化取得长足进展,单机容量从亚兆瓦级迅速提升到兆瓦级,研制中的10MW级风电机组即将问世.机组的大型化提高了风电的经济性和竞争力.风机设备利用率将由目前的25％左右提高至2015年的28％,同时投资成本将大幅下降,按照GWEC的高增长方案预测,投资成本将由2009年的1350欧元/kW降至2030年的1093欧元/kW.鉴于风力发电的间歇性和随机性,蓄电技术成为大量引入可再生能源的有效手段,美欧日等都投入专项经费支持蓄电技术的研究开发.IEA最近在报告中指出,与热电联产组合的方式可大幅扩大可再生能源的利用,其重点在于热供应.智能电网将成为解决风电大规模接入和输送问题的根本途径,它将使电力系统整体利用效率大大提高,有利于抑制发电厂的化石燃料消费.我国在智能电网方面已取得了一定成果,但仍面临许多问题.各国政府的可再生能源电力收购政策促进了风电产业的发展,其中德国的风电收购政策值得我国借鉴.     

The spectrum of power from wind turbines

The power spectral density of the output of wind turbines provides information on the character of fluctuations in turbine output. Here both 1-second and 1-hour samples are used to estimate the power spectrum of several wind farms. The measured output power is found to follow a Kolmogorov spectrum over more than four orders of magnitude, from 30 s to 2.6 days. This result is in sharp contrast to the only previous study covering long time periods, published 50 years ago. The spectrum defines the character of fill-in power that must be provided to compensate for wind's fluctuations when wind is deployed at large scale. Installing enough linear ramp rate generation (such as a gas generator) to fill in fast fluctuations with amplitudes of 1% of the maximum fluctuation would oversize the fill-in generation capacity by a factor of two for slower fluctuations, greatly increasing capital costs. A wind system that incorporates batteries, fuel cells, supercapacitors, or other fast-ramp-rate energy storage systems would match fluctuations much better, and can provide an economic route for deployment of energy storage systems when renewable portfolio standards require large amounts of intermittent renewable generating sources.     

The role of energy storage in accessing remote wind resources in the Midwest

Replacing current generation with wind energy would help reduce the emissions associated with fossil fuel electricity generation. However, integrating wind into the electricity grid is not without cost. Wind power output is highly variable and average capacity factors from wind farms are often much lower than conventional generators. Further, the best wind resources with highest capacity factors are often located far away from load centers and accessing them therefore requires transmission investments. Energy storage capacity could be an alternative to some of the required transmission investment, thereby reducing capital costs for accessing remote wind farms. This work focuses on the trade-offs between energy storage and transmission. In a case study of a 200 MW wind farm in North Dakota to deliver power to Illinois, we estimate the size of transmission and energy storage capacity that yields the lowest average cost of generating and delivering electricity ($/MW h) from this farm. We find that transmission costs must be at least $600/MW-km and energy storage must cost at most $100/kW h in order for this application of energy storage to be economical.     

一种新型双电池风力发电储能系统及控制策略

提出一种新型双电池风电储能系统,它能以较低的运行成本将风电功率波动维持在规定的范围内;风电场可在每个调度时段内输出恒定功率,使风电稳定地并入电网。当调度功率低于实际风电功率时,起充电作用的电池处于工作状态,当调度功率高于实际风电功率时,起放电作用的电池处于工作状态;当其中一个电池充满电或深度放电时,2组电池的充、放电状态切换。为了延长电池使用寿命,对调度功率进行优化,以确保2组电池都在完整充、放电循环下运行,此双电池储能系统可显著降低系统运行成本。利用一台具有真实风电功率数据的3 MW风电机组进行仿真分析,验证了所提系统及控制策略的有效性。     

海上石油平台风燃互补发电孤立小电网稳定性研究及应用

"渤海海上风力发电示范工程"于2007年初批准正式立项,建设国内第一台海上风力发电机组,容量为1.5MW。由于风能具有间歇性和随机性的特点,为了实现绥中36-1CEP平台孤立电网与风电机组互补发电,并且保证该电网的平稳运行,进行了海上平台孤立小电网的稳定性研究。海上石油平台电网允许的正常频率波动范围为±0.25Hz,频率偏差报警为±0.5Hz,电网频率将随着透平发电机组输出有功功率的变化而波动。当风力发电机组在额定输出有功功率跳闸退出电网时,对电网频率的影响最大;当风力发电机组在额定风速启动并网时,对电网频率的影响较大。在特定的风燃互补孤立小电网中,采用电网负荷频率调节方程,可以计算风力发电机组容量与电网总负荷之比和频率波动的关系。海上平台风燃互补发电孤立小电网稳定运行的条件为风力发电机组的容量与平台电网总容量的比值小于10%。在满足风力发电机组引起平台电网最大频率波动范围为±0.25Hz的条件下,额定有功功率为1.5MW的风力发电机组,可并入最低总有功功率为15MW的电网。将稳定性研究结论应用于渤海风力发电示范项目,保证了示范工程的顺利进行,实现了国内第一台海上风力发电机组与生产平台并网发电的稳定运行。     

Forecast study of the supply curve of solar and wind technologies in Argentina,Brazil, Chile and Mexico

This paper forecasts the supply curve of non-conventional renewable technologies such as wind and solar generating stations in Argentina, Brazil, Chile and Mexico using technological and economic parameters. It also estimates the additional investment costs in solar and wind generation for reaching the renewable energy target in each of these countries. To assess the power supply profile from 1 axis tracking PV and horizontal axis wind turbine (three blade) stations, two different scenarios are developed for 2014 and 2025. Scenario 1 estimates the PV and wind annual electricity yield by using polycrystalline silicon (cSi poly) as semiconductor material for PV cells and a Vestas 90–3.0 MW turbine for the wind for 2014.Scenario 2 assumes a more efficient technology, such as CPV. In fact, the model employs 45% efficiency triple junction cells using ∼3500 m2 for each 1 MW installed capacity in 2025. Moreover, this scenario also assumes a more powerful type of turbine, i.e. Vestas 112–3.075 MW. The biggest potential for wind power is found to be in Argentina, followed by Brazil, Mexico and Chile. In addition, a 550 MW installed capacity CPV power station, using triple junction cells could generate up to 4 TWh in Chile in 2025.     

A new semi-empirical wind turbine capacity factor for maximizing annual electricity and hydrogen production

The capacity factor is an important wind turbine parameter which is ratio of average output electrical power to rated electrical power of the wind turbine. Another main factor, the AEP, the annual energy production, can be determined using wind characteristics and wind turbine performance. Lower rated power may lead to higher capacity factor but will reduce the AEP. Therefore, it is important to consider simultaneously both the capacity factor and the AEP in design or selecting a wind turbine. In this work, a new semi-empirical secondary capacity factor is introduced for determining a rated wind speed at which yearly energy and hydrogen production obtain a maximum value. This capacity factor is expressed as ratio of the AEP for wind turbine to yearly wind energy delivered by mean wind speed at the rotor swept area. The methodology is demonstrated using the empirical efficiency curve of Vestas-80 2 MW turbine and the Weibull probability density function. Simultaneous use of the primary and the secondary capacity factors are discussed for maximizing electrical energy and hence hydrogen production for different wind classes and economic feasibility are scrutinized in several wind stations in Kuwait.     

Wind electric power in the world and perspectives of its development in India

The global market for wind power is expanding faster than any other source of renewable energy. From just 4,800 MW in 1995 raise to fifteen-fold to reach 73,904 MW at the end of 2006. Top five wind electric power generating countries at the end of 2006 were Germany, Spain, United States of America (USA), India and Denmark. Since 1980s, when the first commercial wind turbine was deployed, their capacity, efficiency and visual design have all improved a lot. A modern wind turbine annually produces 180 times more electricity at less than half the cost per unit (kWh) than its equivalent twenty years ago. The largest turbines being manufactured now are of rated power of 5 MW capacity and a rotor diameter of 126 m. Modern turbines are modular and quick to install, whilst wind farms vary in size from a few MW to several hundred MW. Keeping these factors in view, an attempt has been made in this paper to present current advances in wind turbine generator technology. Wind energy scenario in the world in general and in India in particular have been presented. Further the cost components of wind turbine electric generation system have been included.     

Inhibition of wind power fluctuations of battery energy storage system adaptive control strategy design

为了增加电池储能系统针对大规模风电并网对电网系统的友好性,降低风电功率波动对电网的不利影响,本文提出以电池荷电状态和风电功率为反馈量,改变平抑时间常数和电池储能系统充放电目标功率为目标的平抑风电功率波动的自适应控制策略。经仿真验证,上述策略能有效避免电池的荷电状态大幅波动,延长电池使用寿命,从而减小电池储能系统的安装容量,最大限度地发挥电池储能系统的作用。     

A probabilistic method for calculating the usefulness of a store with finite energy capacity for smoothing electricity generation from wind and solar power

This paper describes a novel method of modelling an energy store used to match the power output from a wind turbine and a solar PV array to a varying electrical load. The model estimates the fraction of time that an energy store spends full or empty. It can also estimate the power curtailed when the store is full and the unsatisfied demand when the store is empty. The new modelling method has been validated against time–stepping methods and shows generally good agreement over a wide range of store power ratings, store efficiencies, wind turbine capacities and solar PV capacities.Example results are presented for a system with 1 MW of wind power capacity, 2 MW of photovoltaic capacity, an energy store of 75% efficiency and a range of loads from 0 to 3 MW average.     

On the fluctuating power generation of large wind energy converters,with and without storage facilities

The power fluctuations and time duration patterns of large, hypothetical wind energy generators are analysed, using meteorological data for Denmark. It is found that the fluctuations, relative to a load which varies through the year in a manner similar to the actual load, are no greater than the fluctuations relative to a constant load (base-load application). The addition of a hypothetical short-term storage, capable of delivering the average power for 10–20 hr, makes the wind energy system as dependable as one large nuclear power plant, being capable of delivering the average power for about 70 per cent of the time. For full coverage by a wind energy system, an additional long-term storage facility must be added. It is found that for the wind energy conditions of the Danish site considered, a storage holding 40–60 days of average load and with a recovery percentage of 50, will be needed. Due to the energy losses in the storage systems, the installed capacity must be augmented by about 35 per cent. A few remarks are made about the prospects for developing suitable storage facilities, and about the cost of total wind energy systems relative to other means of producing electricity.     

Fault analysis of wind turbine generators in India

Wind energy has become a techno-economically viable source of energy and is considered as a preferable renewable energy resources option in the power sector in India. If the current pace of development is maintained for at least a few decades, India would soon possess the highest windfarm installation in the world and a significant portion of the country's energy needs could be met through wind power. The available wind energy resource can be utilised to the greater extent by optimally siting the windfarms, by appropriate machine selection and by proper maintenance. An attempt has been made to evaluate the performance of wind turbine generators for the largest demonstration windfarm (10 MW) in Asia. This windfarm is situated at Lamba, Gujarat State with 50 wind turbine machines of 200 kW capacity. The technical availability, real availability, capacity factor and maximum down time of the wind turbine generators have been calculated and plotted over the year. About 30 fault conditions have been identified and analysed by pareto diagram.     

浮式风电制氢装置设计研究

对浮式风电制氢装置工程化进行了研究,并基于8～10 MW的浮式风电平台,设计了3 MW独立式风电制氢装置,制定了利用风机发电提供的能源,提取海水进行纯化和电解水制氢的技术路线,提出了关键设备的技术要求,并进行了系统的布置及初步的安全性和经济性分析。结果表明,由于经济性差,海工应用还不成熟,目前海上浮式制氢的工程化还需要一个过程,进行工程试验是大规模工程化的前提。     

Assessing the economic wind power potential in Austria

In the European Union, electricity production from wind energy is projected to increase by approximately 16% until 2020. The Austrian energy plan aims at increasing the currently installed wind power capacity from approximately 1 GW to 3 GW until 2020 including an additional capacity of 700 MW until 2015. The aim of this analysis is to assess economically viable wind turbine sites under current feed-in tariffs considering constraints imposed by infrastructure, the natural environment and ecological preservation zones in Austria. We analyze whether the policy target of installing an additional wind power capacity of 700 MW until 2015 is attainable under current legislation and developed a GIS based decision system for wind turbine site selection.Results show that the current feed-in tariff of 9.7 ct kW h⁻¹ may trigger an additional installation of 3544 MW. The current feed-in tariff can therefore be considered too high as wind power deployment would exceed the target by far. Our results indicate that the targets may be attained more cost-effectively by applying a lower feed-in tariff of 9.1 ct kW h⁻¹. Thus, windfall profits at favorable sites and deadweight losses of policy intervention can be minimized while still guaranteeing the deployment of additional wind power capacities.     

Evaluation of wind energy potential and electricity generation on the coast of Mediterranean Sea in Egypt

Wind data from 10 coastal meteorological stations along the Mediterranean Sea in Egypt have been used for statistical analysis to determine the wind characteristics. It was found that three stations show annual mean wind speed greater than 5.0 m/s. In order to identify the Weibull parameters for all stations two different methods were applied.The methodical analysis for all stations was done for the corrected monthly and annual mean wind power at a height of 10 m, over roughness class 0 (water). The recommended correlation equation was also stated for Mediterranean Sea zone in Egypt. Also the wind power densities for heights of 30–50 m were calculated for all stations. Three of them are the best locations, namely: Sidi Barrani, Mersa Matruh, and El Dabaa, where these contiguous stations have great abundantly wind energy density.A technical assessment has been made of the electricity generation using WASP program for two commercial turbines (300 kW and 1 MW) considering at the three promising sites. The wind turbine of capacity 1 MW was found to produce an energy output per year of 2718 MW h at El Dabaa station, and the production costs was found 2€ cent/kW h.     

风电与燃气轮机发电互补系统结构与容量配比的研究

对在我国新疆地区采用风力发电与燃气轮机发电组成的互补发电系统的结构和在一定风能资源条件下两种发电系统的容量配比进行了研究。论文首先针对实测的新疆达坂城风电场的风速数据,采用整体风电场功率输出模型,得到了风电场的输出与分布。根据实际的风电场输出负荷,设计了互补中燃气轮机的几种方案。针对燃气轮机的部分负荷运行特点,设计了不同方案的互补运行规则。最后根据不同运行规则,计算了互补系统的整体特性,得到了在一定条件下风电与燃气轮机发电较合适的容量配比。     

Wind power smoothing using fuzzy logic pitch controller and energy capacitor system for improvement Micro-Grid performance in islanding mode

The need of reducing CO₂ emissions in electricity generation field for solving global warming problems has led to increase interest in Micro-Grid (MG) especially the one with renewable sources such as solar and wind generations. Wind speed fluctuations cause high fluctuations in output power of wind turbine which cause fluctuations in fr and voltages of the MG in the islanding mode and originate stability problems. In this study, a new fuzzy logic pitch controller and an energy storage ultra capacitor are proposed and developed to smooth the output power of wind turbine and enhance MG's performance in islanding mode. These two proposed controllers are compared with the conventional PI pitch controller, which is usually used to control wind generation system when the wind speed exceeds a rated value. Obtained results proved that our two proposed strategies are effective for the MG performance improvement during islanding mode. All models and controllers are developed using Matlab^® Simulink^® environment.     

基于时频分析的改进小波包风电功率波动平抑方法

针对传统小波包风电波动平抑方法存在的过度平抑问题,提出一种基于时频分析的改进小波包平抑方法。首先,找出功率最大变化范围超过波动标准的时刻对集合,利用小波包对风电功率进行小波分解得到各频段分量;然后,从高频到低频依次对各频段分量在时刻对集合上进行局部削峰填谷,直到风电功率满足波动标准,从而得到平抑后的风电并网功率和储能功率指令;最后,对波动平抑效果进行评价。算例仿真表明该方法在满足风电波动标准的基础上,减小了储能功率指令的累积功率和充放电切换次数,有利于降低储能配置成本、延长储能寿命。