Modeling of the dynamics of wind to power conversion including high wind speed behavior

This paper proposes and validates an efficient, generic and computationally simple dynamic model for the conversion of the wind speed at hub height into the electrical power by a wind turbine. This proposed wind turbine model was developed as a first step to simulate wind power time series for power system studies. This paper focuses on describing and validating the single wind turbine model, and is therefore neither describing wind speed modeling nor aggregation of contributions from a whole wind farm or a power system area. The state‐of‐the‐art is to use static power curves for the purpose of power system studies, but the idea of the proposed wind turbine model is to include the main dynamic effects in order to have a better representation of the fluctuations in the output power and of the fast power ramping especially because of high wind speed shutdowns of the wind turbine. The high wind speed shutdowns and restarts are represented as on–off switching rules that govern the output of the wind turbine at extreme wind speed conditions. The model uses the concept of equivalent wind speed, estimated from the single point (hub height) wind speed using a second‐order dynamic filter that is derived from an admittance function. The equivalent wind speed is a representation of the averaging of the wind speeds over the wind turbine rotor plane and is used as input to the static power curve to get the output power. The proposed wind turbine model is validated for the whole operating range using measurements available from the DONG Energy offshore wind farm Horns Rev 2. Copyright © 2015 John Wiley & Sons, Ltd.     

Rotor dynamics correlation for maximum power and transient control of wind turbines

In this paper, a new rotor dynamics model is developed for transient power output from a horizontal axis wind turbine. In addition to the standard maximum kinetic energy of the wind, the model incorporates rotor velocity and rotational acceleration to enhance the control techniques that convert mechanical to electrical energy via shaft rotation. With current methods, the wind kinetic energy is generally the primary parameter that establishes maximum power output. By relating this wind energy to the rotor dynamics, electrical systems can have a more useful upper bound for the rotor control strategy. The new model predicts the rotor velocity for various turbine configurations, operating over a range of wind conditions. The predicted results show that the same power output is obtained as the standard kinetic energy approach, but with significant additional opportunity to better control the rotor dynamics. Copyright © 2009 John Wiley & Sons, Ltd.     

风电机组的型式认证和风电场认证--IEC风电机组认证标准介绍

本文介绍的型式认证和风电场认证是依据国际电工委员会IECWT01：2001标准风电机组合格测试与认证体系规则及程序。型式认证的步骤包括设计评估、生产评估、质量管理评估以及型式实验。风电场认证是在型式认证完成后进行，包括场地评估、基础设计评估、安装评估（可选）一旦型式认证和风电场认证的相关工作完成后将签发认证证书。     

风电与燃气轮机互补发电系统发电成本分析

在采用风电场与小型燃气轮机组成的互补系统发电特性参数的基础上,详细分析了互补系统发电成本的构成和各自的计算方法。采用新疆达坂城风电场的风速数据,基于互补系统的发电特性参数和风电场与燃气轮机电站的发电成本构成,应用改进过的等额支付折算法,在当前的技术条件和价格下,计算了风电场子系统和燃气轮机电站子系统各自的折旧成本、燃料成本和运行维护成本,得到了整滚发电系统发电成本的计算方法,为在新疆地区实现这种互补发电系统提供经济分析基础。     

Economic wind power

The development of a cheap rugged windmill—from the initial wind tunnel tests, through power output/capital investment optimisation exercises to the final design and running—is traced. It is suggested that further development along the lines indicated could well result in economic wind power.     

Alternative wind power : A next generation wind power technology?

Present day wind turbines (large blade Props on Pole or POPs) have continued to evolve to ever larger sizes requiring massive blades, gearboxes or large, complex customized generators. This continuous increase in size has subsequently increased the costs and complexity of manufacturing, transporting, constructing and maintaining these systems. In this article, Alfred L. Weisbrich, ENECO Texas LLC, USA discusses an alternative wind power technology design, the Wind Amplified Rotor Platform (WARP^TM) which uses many identical smaller vertically integrated modules as opposed to one large generator. The modular design can be easily and relatively inexpensively volume produced and implemented both in traditional electric utility scale wind farms as well as in marine based offshore wind farms sites.     

第三讲风力发电用的发电机及风力发电系统

风能是我国目前开发利用比较成熟的一种新能源,风电事业正在我国蓬勃发展.为了帮助读者了解风力发电知识,我们请长期从事风力发电研究工作的中国科学院电工研究所倪受元研究员撰写了<风力发电>讲座,以飨读者.     

Hydrogen energy storage systems to improve wind power plant efficiency considering electricity tariff dynamics

One of the limitations of the efficiency of renewable energy sources is the stochastic nature of generation; consequently, it is necessary to use high-capacity energy storage systems such as hydrogen storage for its integration into existing power networks. At the same time, electricity market tariffs for large enterprises change during the day. Therefore, it can be assumed that storing energy during cheaper hours and usage in more expensive hours allows increasing the efficiency of renewable energy sources. Evaluation of the economic efficiency of an energy storage system requires simulation with a step of at least 1 h for several years since the use of averaged production volume and averaged electricity tariffs will not allow obtaining an adequate to the task accuracy. A simulation model and software have been implemented to perform simulations and calculate the economic efficiency of a wind turbine with and without a hydrogen storage device. The methodology has been approved on three-year real data of wind speeds and electricity tariffs in the Novosibirsk region and Krasnodar Territory (Russian Federation).     

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.     

风电系统的无功功率与电网电压稳定

论述了风电容量在占局部电网相当比例时,风电机组的无功功率调整与电网电压之间的关系,对于定速和变速风电机组的运行特性做了分析,提出了在需要做无功功率调整时风电机组应能满足的特殊要求。     

分散式风力发电机组的电压控制

风电的分散式开发不同于大规模开发和分布式开发,由于分散风电靠近负荷中心,直接接入配电网,且不加装无功补偿调节装置SVC,配网中较大的电压波动给分散风电的并网运行带来影响。文章讨论了配网对分散风电的电压控制特点和要求,结合风电机组无功控制能力,并推导出满足配网电压调节要求的风电机组无功控制范围和对机组设备的要求。     

风 风能 风力发电——21世纪新型清洁能源

一风的一般属性１风的形成风是人们非常熟悉的一种自然现象，人人都能感觉到它的存在。春风和煦，给万物带来生机；夏风吹拂，使人心旷神怡；秋风送爽，带来丰收的喜悦；冬风呼啸，迎来漫天飞雪。那么风是怎样形成的呢？众所周知，人类生活的地球表面被大气所包围，来自太阳的辐射不断传送到地球表面，因太阳辐射受热情况不同，地球表面各处的气温不同。在影响气压高低的因素中，气温起着最重要的作用。温度高的地区空气受热上升，气压减小；温度低的地方，空气下降，气压增大，于是产生了气压差。和水往低处流一样，空气也从气压高处向气压…     

风电高速发展中存在的若干问题

20世纪80年代,我国引入首台并网型风电机组,之后较长的一段时间增长缓慢,风电场处于试验阶段.自2003年起,风电发展逐渐加速,装机规模逐年翻番.2007年底,全国风电装机容量590万kW.单一机型在5年内由百瓦级经过千瓦级发展到目前的兆瓦级机组,单一风电场的规模从几十兆瓦迅速发展到几百兆瓦,风电场送出电压等级从过去的35kV为主体迅速发展为以220kV为主体.国内内资企业风机产能从2005年15万kW、2006年55万kW,发展到2007年的180万kW.风电产业发展速度十分迅猛.     

The wind power of Mexico

The high price of fossil fuels and the environmental damage they cause have encouraged the development of renewable energy resources, especially wind power. This work discusses the potential of wind power in Mexico, using data collected every 10 min between 2000 and 2008 at 133 automatic weather stations around the country. The wind speed, the number of hours of wind useful for generating electricity and the potential electrical power that could be generated were estimated for each year via the modelling of a wind turbine employing a logistic curve. A linear correlation of 90.3% was seen between the mean annual wind speed and the mean annual number of hours of useful wind. Maps were constructed of the country showing mean annual wind speeds, useful hours of wind, and the electrical power that could be generated. The results show that Mexico has great wind power potential with practically the entire country enjoying more than 1700 h of useful wind per year and the potential to generate over 2000 kW of electrical power per year per wind turbine installed (except for the Chiapas's State). Indeed, with the exception of six states, over 5000 kW per year could be generated by each turbine.     

风力发电前景广阔

被称为“蓝天白煤”的风力资源,是一种取之不尽,又不会产生任何污染的可再生能源。人类早在远古时代便开始利用风力,但直到１９世纪末丹麦才建成全球第一个风力发电装置。由于风力发电与火电、核电、水电等其它发电方式相比有诸多优点,所以,本世纪８０年代以来,世界风电装机容量迅猛增长。１９８１年为１５兆瓦,１９９２年已达２６５２兆瓦,１３%的年增长率使风力发电成为世界上增长速度最快的发电方式之一,目前仍保持着快速发展的势头。１９９９年１０月５日,欧洲风能协会在布鲁塞尔发表了一项国际能源研究报告。报告称,风力发电到２０２０…     

Simulation of hourly wind speed and array wind power

Statistical summaries of wind speed are sufficient to compute many characteristics of turbine-generated power, such as the mean, variance and reliability of various power levels. However, a wind speed time series is necessary to produce a sequence of power values as used for investigating load matching and storage requirements. Since a long historical record of wind speed may not be available at a wind turbine candidate site, it is desirable to be able to generate a simulated numerical sequence of hourly wind speed values. Two such approximate procedures are developed in this paper. One procedure generates sequential wind speed values at a site based on the Weibull parameters of hourly wind speed and the lag-one autocorrelation of hourly wind speed values. Comparison with historical data at a site is made. The second procedure generates sequential hourly wind power values for a regional array of wind turbines. It utilizes the typical site wind characteristics, the spatial and lag-one cross correlation and autocorrelation of hourly wind speed values and an equivalent linearized relationship between array average wind speed and array power. Comparison with results for six different wind turbines in three different regional arrays indicates good agreement for wind power histograms, autocorrelation function and mean persistence.     

Analysing wind power ramp events and improving very short-term wind power predictions by including wind speed observations

Though wind power predictions have been consistently improved in the last decade, persistent reasons for remaining uncertainties are sudden large changes in wind speed, so-called ramps. Here, we analyse the occurrence of ramp events in a wind farm in Eastern Germany and the performance of a wind power prediction tool in forecasting these events for forecasting horizons of 15 and 30 min. Results on the seasonality of ramp events and their diurnal cycle are presented for multiple ramp definition thresholds. Ramps were found to be most frequent in March and April and least frequent in November and December. For the analysis, the wind power prediction tool is fed by different wind velocity forecast products, for example, numerical weather prediction (NWP) model and measurement data. It is shown that including observational wind speed data for very short-term wind power forecasts improves the performance of the power prediction tool compared to the NWP reference, both in terms of ramp detection and in decreasing the mean absolute error between predicted and generated wind power. This improvement is enhanced during ramp events, highlighting the importance of wind observations for very short-term wind power prediction.     

第六讲 风力发电的现状和展望

风能是我国目前开发利用比较成熟的一种新能源,风电事业正在我国蓬勃发展。为了帮助读者了解风力发电知识,我们请长期从事风力发电研究工作的中国科学院电工研究所倪受元研究员撰写了《风力发电》讲座以飨读者。———编者     

考虑平衡风电出力偏差的风电-抽水蓄能联合运行模式研究

风电出力的实际值与预期值的偏差较大会对电网的安全稳定运行带来冲击,从而制约风电大规模并网。为解决这一问题,文章提出在电力市场环境下通过风电-抽水蓄能联合运行的方式来弥补风电出力偏差。在研究独立运行模式的基础上建立联合运行模型,研究两种模式下抽水蓄能电站的经济效益以及联合运行模式的综合效益。算例分析验证了风电-抽水蓄能联合运行模式在技术上与经济上的可行性,联合运行模式虽然在一定程度上减少了抽水蓄能电站的电量收益,但实际综合效益比独立运行模式的经济效益有大幅度提高。