Smoothing Control of Wind Farm Output by Using Kinetic Energy of Variable Speed Wind Power Generators

Science.gov (United States)

Sato, Daiki; Saitoh, Hiroumi

This paper proposes a new control method for reducing fluctuation of power system frequency through smoothing active power output of wind farm. The proposal is based on the modulation of rotaional kinetic energy of variable speed wind power generators through power converters between permanent magnet synchronous generators (PMSG) and transmission lines. In this paper, the proposed control is called Fluctuation Absorption by Flywheel Characteristics control (FAFC). The FAFC can be easily implemented by adding wind farm output signal to Maximum Power Point Tracking control signal through a feedback control loop. In order to verify the effectiveness of the FAFC control, a simulation study was carried out. In the study, it was assumed that the wind farm consisting of PMSG type wind power generator and induction machine type wind power generaotors is connected with a power sysem. The results of the study show that the FAFC control is a useful method for reducing the impacts of wind farm output fluctuation on system frequency without additional devices such as secondary battery.

Quantifying the Impact of Wind Turbine Wakes on Power Output at Offshore Wind Farms

DEFF Research Database (Denmark)

Barthelmie, Rebecca Jane; Pryor, Sara; Frandsen, Sten Tronæs

2010-01-01

There is an urgent need to develop and optimize tools for designing large wind farm arrays for deployment offshore. This research is focused on improving the understanding of, and modeling of, wind turbine wakes in order to make more accurate power output predictions for large offshore wind farms...

Coordinated frequency control from offshore wind power plants connected to multi terminal DC system considering wind speed variation

DEFF Research Database (Denmark)

Sakamuri, Jayachandra N.; Altin, Müfit; Hansen, Anca Daniela

2017-01-01

A coordinated fast primary frequency control scheme from offshore wind power plants (OWPPs) integrated to a three terminal high voltage DC (HVDC) system is proposed in this study. The impact of wind speed variation on the OWPP active power output and thus on the AC grid frequency and DC grid...... the active power support from OWPP with a ramp rate limiter and (iii) An alternative method for the wind turbine overloading considering rotor speed. The effectiveness of the proposed control scheme is demonstrated on a wind power plant integrated into a three terminal HVDC system developed in DIg......SILIENT PowerFactory. The results show that the proposed coordinated frequency control method performs effectively at different wind speeds and minimises the secondary effects on frequency and DC voltage....

Measuring power output intermittency and unsteady loading in a micro wind farm model

OpenAIRE

Bossuyt, Juliaan; Howland, Michael; Meneveau, Charles; Meyers, Johan

2016-01-01

In this study porous disc models are used as a turbine model for a wind-tunnel wind farm experiment, allowing the measurement of the power output, thrust force and spatially averaged incoming velocity for every turbine. The model's capabilities for studying the unsteady turbine loading, wind farm power output intermittency and spatio temporal correlations between wind turbines are demonstrated on an aligned wind farm, consisting of 100 wind turbine models.

Effects of wake effect and time delay on output characteristics of doubly fed induction generators in wind power plant%尾流效应和时滞对双馈机组风电场输出特性的影响

Institute of Scientific and Technical Information of China (English)

2013-01-01

　　由于双馈机组已成为国内主流机型且大型双馈机组风电场通常占地面积比较大，需要研究双馈风电机组间的尾流效应及时滞对双馈机组风电场的并网点输出特性的影响情况。通过搭建了30台2 MW双馈风电机组组成的风电场模型，对风速波动和电网故障下双馈机组风电场输出特性进行分析和比较。通过仿真表明，机组间的尾流效应导致双馈机组风电场的风能损失；风速时滞平缓了风电场输出功率。%Because doubly fed induction generator has become the mainstream type and a large wind power plant usually covers a larger area,the impacts of wake effects among wind turbines and time delay on output characteristics of wind power plant need to be studied. With a wind power plant model composed of thirty 2⁃MW double fed induction generator wind tur⁃bines,the output characteristic of wind power plant under the conditions of wind speed fluctuation and grid faults is analyzed and compared. The simulation results show that the wake effects among wind turbines can cause the wind energy loss of wind farm and the wind speed time delay will smooth the power output of wind farm;wake effects among wind turbines and wind speed time delays needs to be considered when the grid⁃connection stability of wind farms with double fed induction generator wind turbines is analyzed.

Using machine learning to predict wind turbine power output

International Nuclear Information System (INIS)

Clifton, A; Kilcher, L; Lundquist, J K; Fleming, P

2013-01-01

Wind turbine power output is known to be a strong function of wind speed, but is also affected by turbulence and shear. In this work, new aerostructural simulations of a generic 1.5 MW turbine are used to rank atmospheric influences on power output. Most significant is the hub height wind speed, followed by hub height turbulence intensity and then wind speed shear across the rotor disk. These simulation data are used to train regression trees that predict the turbine response for any combination of wind speed, turbulence intensity, and wind shear that might be expected at a turbine site. For a randomly selected atmospheric condition, the accuracy of the regression tree power predictions is three times higher than that from the traditional power curve methodology. The regression tree method can also be applied to turbine test data and used to predict turbine performance at a new site. No new data are required in comparison to the data that are usually collected for a wind resource assessment. Implementing the method requires turbine manufacturers to create a turbine regression tree model from test site data. Such an approach could significantly reduce bias in power predictions that arise because of the different turbulence and shear at the new site, compared to the test site. (letter)

Analysis of losses within SMES system for compensating output fluctuation of wind power farm

Energy Technology Data Exchange (ETDEWEB)

Park, S. I.; Kim, J. H.; Le, T. D.; Lee, D. H.; Kim, H. M. [Jeju National University, Jeju (Korea, Republic of); Yoon, Y. S. [Dept. of Electrical Engineering, Shin Ansan University, Ansan (Korea, Republic of); Yoon, K. Y. [Dept. of lectrical and Electronic Engineering, Yonsei University, Seoul (Korea, Republic of)

2014-12-15

Output fluctuation which is generated in wind power farm can hinder stability of total power system. The electric energy storage (EES) reduces unstable output, and superconducting magnetic energy storage (SMES) of various EESs has the proper performance for output compensation of wind power farm since it charges and discharges large scale power quickly with high efficiency. However, because of the change of current within SMES, the electromagnetic losses occur in the process of output compensation. In this paper, the thermal effect of the losses that occur in SMES system while compensating in wind power farm is analyzed. The output analysis of wind power farm is processed by numerical analysis, and the losses of SMES system is analyzed by 3D finite element analysis (FEA) simulation tool.

Analysis of losses within SMES system for compensating output fluctuation of wind power farm

International Nuclear Information System (INIS)

Park, S. I.; Kim, J. H.; Le, T. D.; Lee, D. H.; Kim, H. M.; Yoon, Y. S.; Yoon, K. Y.

2014-01-01

Output fluctuation which is generated in wind power farm can hinder stability of total power system. The electric energy storage (EES) reduces unstable output, and superconducting magnetic energy storage (SMES) of various EESs has the proper performance for output compensation of wind power farm since it charges and discharges large scale power quickly with high efficiency. However, because of the change of current within SMES, the electromagnetic losses occur in the process of output compensation. In this paper, the thermal effect of the losses that occur in SMES system while compensating in wind power farm is analyzed. The output analysis of wind power farm is processed by numerical analysis, and the losses of SMES system is analyzed by 3D finite element analysis (FEA) simulation tool.

Balancing Europe's wind power output through spatial deployment informed by weather regimes.

Science.gov (United States)

Grams, Christian M; Beerli, Remo; Pfenninger, Stefan; Staffell, Iain; Wernli, Heini

2017-08-01

As wind and solar power provide a growing share of Europe's electricity1, understanding and accommodating their variability on multiple timescales remains a critical problem. On weekly timescales, variability is related to long-lasting weather conditions, called weather regimes2-5, which can cause lulls with a loss of wind power across neighbouring countries6. Here we show that weather regimes provide a meteorological explanation for multi-day fluctuations in Europe's wind power and can help guide new deployment pathways which minimise this variability. Mean generation during different regimes currently ranges from 22 GW to 44 GW and is expected to triple by 2030 with current planning strategies. However, balancing future wind capacity across regions with contrasting inter-regime behaviour - specifically deploying in the Balkans instead of the North Sea - would almost eliminate these output variations, maintain mean generation, and increase fleet-wide minimum output. Solar photovoltaics could balance low-wind regimes locally, but only by expanding current capacity tenfold. New deployment strategies based on an understanding of continent-scale wind patterns and pan-European collaboration could enable a high share of wind energy whilst minimising the negative impacts of output variability.

Wind power plant

Energy Technology Data Exchange (ETDEWEB)

Weiss, G

1975-11-20

A wind power plant is proposed suitable for electicity generation or water pumping. This plant is to be self-adjusting to various wind velocities and to be kept in operation even during violent storms. For this purpose the mast, carrying the wind rotor and pivotable around a horizontal axis is tiltable and equipped with a wind blind. Further claims contain various configurations of the tilting base resp. the cut in of an elastic link, the attachment and design of the wind blind as well as the constructive arrangement of one or more dynamos.

Sliding Window Technique for Calculating System LOLP Contributions of Wind Power Plants

International Nuclear Information System (INIS)

Milligan, M. R.

2001-01-01

Conventional electric power generation models do not typically recognize the probabilistic nature of the power variations from wind plants. Most models allow for an accurate hourly representation of wind power output, but do not incorporate any probabilistic assessment of whether the given level of wind power will vary from its expected value. The technique presented in this paper uses this variation to calculate an effective forced-outage rate for wind power plants (EFORW). Depending on the type of wind regime undergoing evaluation, the length and diurnal characteristics of a sliding time window can be adjusted so that the EFORW is based on an appropriate time scale. The algorithm allows us to calculate the loss-of-load probability (LOLP) on an hourly basis, fully incorporating the variability of the wind resource into the calculation. This makes it possible to obtain a more accurate assessment of reliability of systems that include wind generation when system reliability is a concern

A model to predict the power output from wind farms

Energy Technology Data Exchange (ETDEWEB)

Landberg, L. [Riso National Lab., Roskilde (Denmark)

1997-12-31

This paper will describe a model that can predict the power output from wind farms. To give examples of input the model is applied to a wind farm in Texas. The predictions are generated from forecasts from the NGM model of NCEP. These predictions are made valid at individual sites (wind farms) by applying a matrix calculated by the sub-models of WASP (Wind Atlas Application and Analysis Program). The actual wind farm production is calculated using the Riso PARK model. Because of the preliminary nature of the results, they will not be given. However, similar results from Europe will be given.

Dynamic Modeling and Very Short-term Prediction of Wind Power Output Using Box-Cox Transformation

Science.gov (United States)

Urata, Kengo; Inoue, Masaki; Murayama, Dai; Adachi, Shuichi

2016-09-01

We propose a statistical modeling method of wind power output for very short-term prediction. The modeling method with a nonlinear model has cascade structure composed of two parts. One is a linear dynamic part that is driven by a Gaussian white noise and described by an autoregressive model. The other is a nonlinear static part that is driven by the output of the linear part. This nonlinear part is designed for output distribution matching: we shape the distribution of the model output to match with that of the wind power output. The constructed model is utilized for one-step ahead prediction of the wind power output. Furthermore, we study the relation between the prediction accuracy and the prediction horizon.

Reactive Power Pricing Model Considering the Randomness of Wind Power Output

Science.gov (United States)

Dai, Zhong; Wu, Zhou

2018-01-01

With the increase of wind power capacity integrated into grid, the influence of the randomness of wind power output on the reactive power distribution of grid is gradually highlighted. Meanwhile, the power market reform puts forward higher requirements for reasonable pricing of reactive power service. Based on it, the article combined the optimal power flow model considering wind power randomness with integrated cost allocation method to price reactive power. Meanwhile, considering the advantages and disadvantages of the present cost allocation method and marginal cost pricing, an integrated cost allocation method based on optimal power flow tracing is proposed. The model realized the optimal power flow distribution of reactive power with the minimal integrated cost and wind power integration, under the premise of guaranteeing the balance of reactive power pricing. Finally, through the analysis of multi-scenario calculation examples and the stochastic simulation of wind power outputs, the article compared the results of the model pricing and the marginal cost pricing, which proved that the model is accurate and effective.

Brief communication: On the influence of vertical wind shear on the combined power output of two model wind turbines in yaw

Directory of Open Access Journals (Sweden)

J. Schottler

2017-08-01

Full Text Available The effect of vertical wind shear on the total power output of two aligned model wind turbines as a function of yaw misalignment of the upstream turbine is studied experimentally. It is shown that asymmetries of the power output of the downstream turbine and the combined power of both with respect to the upstream turbine's yaw misalignment angle can be linked to the vertical wind shear of the inflow.

Validation of Power Output for the WIND Toolkit

Energy Technology Data Exchange (ETDEWEB)

King, J.; Clifton, A.; Hodge, B. M.

2014-09-01

Renewable energy integration studies require wind data sets of high quality with realistic representations of the variability, ramping characteristics, and forecast performance for current wind power plants. The Wind Integration National Data Set (WIND) Toolkit is meant to be an update for and expansion of the original data sets created for the weather years from 2004 through 2006 during the Western Wind and Solar Integration Study and the Eastern Wind Integration Study. The WIND Toolkit expands these data sets to include the entire continental United States, increasing the total number of sites represented, and it includes the weather years from 2007 through 2012. In addition, the WIND Toolkit has a finer resolution for both the temporal and geographic dimensions. Three separate data sets will be created: a meteorological data set, a wind power data set, and a forecast data set. This report describes the validation of the wind power data set.

Wind tunnel study of the power output spectrum in a micro wind farm

International Nuclear Information System (INIS)

Bossuyt, Juliaan; Meyers, Johan; Howland, Michael F.; Meneveau, Charles

2016-01-01

Instrumented small-scale porous disk models are used to study the spectrum of a surrogate for the power output in a micro wind farm with 100 models of wind turbines. The power spectra of individual porous disk models in the first row of the wind farm show the expected -5/3 power law at higher frequencies. Downstream models measure an increased variance due to wake effects. Conversely, the power spectrum of the sum of the power over the entire wind farm shows a peak at the turbine-to-turbine travel frequency between the model turbines, and a near -5/3 power law region at a much wider range of lower frequencies, confirming previous LES results. Comparison with the spectrum that would result when assuming that the signals are uncorrelated, highlights the strong effects of correlations and anti-correlations in the fluctuations at various frequencies. (paper)

Wind power plant

Energy Technology Data Exchange (ETDEWEB)

Kling, A

1977-01-13

The wind power plant described has at least one rotor which is coupled to an electricity generator. The systems are fixed to a suspended body so that it is possible to set up the wind power plant at greater height where one can expect stronger and more uniform winds. The anchoring on the ground or on a floating body is done by mooring cables which can simultaneously have the function of an electric cable. The whole system can be steered by fins. The rotor system itself consists of at least one pair of contrarotating, momentum balanced rotors.

Aggregated wind power plant models consisting of IEC wind turbine models

DEFF Research Database (Denmark)

Altin, Müfit; Göksu, Ömer; Hansen, Anca Daniela

2015-01-01

The common practice regarding the modelling of large generation components has been to make use of models representing the performance of the individual components with a required level of accuracy and details. Owing to the rapid increase of wind power plants comprising large number of wind...... turbines, parameters and models to represent each individual wind turbine in detail makes it necessary to develop aggregated wind power plant models considering the simulation time for power system stability studies. In this paper, aggregated wind power plant models consisting of the IEC 61400-27 variable...... speed wind turbine models (type 3 and type 4) with a power plant controller is presented. The performance of the detailed benchmark wind power plant model and the aggregated model are compared by means of simulations for the specified test cases. Consequently, the results are summarized and discussed...

Use of Bayesian networks classifiers for long-term mean wind turbine energy output estimation at a potential wind energy conversion site

Energy Technology Data Exchange (ETDEWEB)

Carta, Jose A. [Department of Mechanical Engineering, University of Las Palmas de Gran Canaria, Campus de Tafira s/n, 35017 Las Palmas de Gran Canaria, Canary Islands (Spain); Velazquez, Sergio [Department of Electronics and Automatics Engineering, University of Las Palmas de Gran Canaria, Campus de Tafira s/n, 35017 Las Palmas de Gran Canaria, Canary Islands (Spain); Matias, J.M. [Department of Statistics, University of Vigo, Lagoas Marcosende, 36200 Vigo (Spain)

2011-02-15

Due to the interannual variability of wind speed a feasibility analysis for the installation of a Wind Energy Conversion System at a particular site requires estimation of the long-term mean wind turbine energy output. A method is proposed in this paper which, based on probabilistic Bayesian networks (BNs), enables estimation of the long-term mean wind speed histogram for a site where few measurements of the wind resource are available. For this purpose, the proposed method allows the use of multiple reference stations with a long history of wind speed and wind direction measurements. That is to say, the model that is proposed in this paper is able to involve and make use of regional information about the wind resource. With the estimated long-term wind speed histogram and the power curve of a wind turbine it is possible to use the method of bins to determine the long-term mean energy output for that wind turbine. The intelligent system employed, the knowledgebase of which is a joint probability function of all the model variables, uses efficient calculation techniques for conditional probabilities to perform the reasoning. This enables automatic model learning and inference to be performed efficiently based on the available evidence. The proposed model is applied in this paper to wind speeds and wind directions recorded at four weather stations located in the Canary Islands (Spain). Ten years of mean hourly wind speed and direction data are available for these stations. One of the conclusions reached is that the BN with three reference stations gave fewer errors between the real and estimated long-term mean wind turbine energy output than when using two measure-correlate-predict algorithms which were evaluated and which use a linear regression between the candidate station and one reference station. (author)

Use of Bayesian networks classifiers for long-term mean wind turbine energy output estimation at a potential wind energy conversion site

International Nuclear Information System (INIS)

Carta, Jose A.; Velazquez, Sergio; Matias, J.M.

2011-01-01

Due to the interannual variability of wind speed a feasibility analysis for the installation of a Wind Energy Conversion System at a particular site requires estimation of the long-term mean wind turbine energy output. A method is proposed in this paper which, based on probabilistic Bayesian networks (BNs), enables estimation of the long-term mean wind speed histogram for a site where few measurements of the wind resource are available. For this purpose, the proposed method allows the use of multiple reference stations with a long history of wind speed and wind direction measurements. That is to say, the model that is proposed in this paper is able to involve and make use of regional information about the wind resource. With the estimated long-term wind speed histogram and the power curve of a wind turbine it is possible to use the method of bins to determine the long-term mean energy output for that wind turbine. The intelligent system employed, the knowledgebase of which is a joint probability function of all the model variables, uses efficient calculation techniques for conditional probabilities to perform the reasoning. This enables automatic model learning and inference to be performed efficiently based on the available evidence. The proposed model is applied in this paper to wind speeds and wind directions recorded at four weather stations located in the Canary Islands (Spain). Ten years of mean hourly wind speed and direction data are available for these stations. One of the conclusions reached is that the BN with three reference stations gave fewer errors between the real and estimated long-term mean wind turbine energy output than when using two measure-correlate-predict algorithms which were evaluated and which use a linear regression between the candidate station and one reference station.

Control Strategies for Smoothing of Output Power of Wind Energy Conversion Systems

Science.gov (United States)

Pratap, Alok; Urasaki, Naomitsu; Senju, Tomonobu

2013-10-01

This article presents a control method for output power smoothing of a wind energy conversion system (WECS) with a permanent magnet synchronous generator (PMSG) using the inertia of wind turbine and the pitch control. The WECS used in this article adopts an AC-DC-AC converter system. The generator-side converter controls the torque of the PMSG, while the grid-side inverter controls the DC-link and grid voltages. For the generator-side converter, the torque command is determined by using the fuzzy logic. The inputs of the fuzzy logic are the operating point of the rotational speed of the PMSG and the difference between the wind turbine torque and the generator torque. By means of the proposed method, the generator torque is smoothed, and the kinetic energy stored by the inertia of the wind turbine can be utilized to smooth the output power fluctuations of the PMSG. In addition, the wind turbines shaft stress is mitigated compared to a conventional maximum power point tracking control. Effectiveness of the proposed method is verified by the numerical simulations.

Mastering the power of wind

International Nuclear Information System (INIS)

Stiegel, J.

1999-01-01

In this paper the author deals with environmental aspects use of fossil fuels for the energy production. As a way for our planet to get back to a normal and ecologically balanced system the fossil fuels reduction and their replacement by renewable racecourses is recommended. Energetic potential of flowing sun, wind and tidal waves as power resources is discussed. The natural ecological resources are best utilised in the United States where the installed wind power output is 1600 MW. With 360 MW installed output in 1991 the Denmark took lead among European countries in utilising the wind power. The most dynamic power plant development among the European Union countries was recorded in Germany, where the installed power output of the wind power plants is 632 MW, i.e. i.e. 11.5 times higher compared to 55 MW in 1991. The economy of wind power in Germany and in Slovakia is compared. In Slovakia with annual 200 000 kWh power generation annually and the present kWh purchase price guarantee the rate of return of 10 million slovak crowns investment into a wind power plant project is in 100 years. Although the first wind power plants have already been built in the Zahorie, Kremnicke Bane, and Secovce regions, the wind exploitation status in Slovakia is still limping. According to professionals, the wind conditions in Slovakia are not ideal, but sufficient for a supplementary wind power plant system, that can be quite motivating especially for villages. Mount Chopok or mount Krizna are ideal sites to erect the three-blade tower with respect to wind speed. And also the anticipated Kremnicke vrchy site is worth considering. (author)

Induced Torques on Synchronous Generators from Operation of Wind Power Plant based on Full-Load Converter Interfaced Wind Turbines

DEFF Research Database (Denmark)

Knüppel, Thyge; Nielsen, Jørgen N.; Jensen, Kim H.

2011-01-01

It is expected that large wind power plants (WPP) contribute to stable and reliable operation of the electric power system. This includes participation with delivery of system services such as voltage and frequency support. With variable-speed WPPs this can be achieved by adding auxiliary...... be predicted with the presented method. The work is based on a nonlinear, dynamic model of the 3.6 MW Siemens Wind Power wind turbine....... controllers that control the active and reactive power output accordingly. While being designed for a given system service, any feedback control affects the closed-loop behavior of the overall system and thereby its small-signal stability properties. Eigenvalue analysis conveniently determines the stability...

Estimation of monthly wind power outputs of WECS with limited record period using artificial neural networks

International Nuclear Information System (INIS)

Tu, Yi-Long; Chang, Tsang-Jung; Chen, Cheng-Lung; Chang, Yu-Jung

2012-01-01

Highlights: ► ANN with short record training data is used to estimate power outputs in an existing station. ► The suitable numbers/parameters of input neurons for ANN are presented. ► Current wind speeds and previous power outputs are the most important input neurons. ► Choosing suitable input parameters is more important than choosing multiple parameters. - Abstract: For the brand new wind power industry, online recordings of wind power data are always in a relatively limited period. The aim of the study is to investigate the suitable numbers/parameters of input neurons for artificial neural networks under a short record of measured data. Measured wind speeds, wind directions (yaw angles) and power outputs with 10-min resolution at an existing wind power station, located at Jhongtun, Taiwan, are integrated to form three types of input neuron numbers and sixteen cases of input neurons. The first-10 days of each month in 2006 are used for data training to simulate the following 20-day power generation of the same month. The performance of various input neuron cases is evaluated. The simulated results show that using the first 10-day training data with adequate input neurons can estimate energy outputs well except the weak wind regime (May, June, and July). Among the input neuron parameters used, current wind speeds V(t) and previous power outputs P(t − 1) are the most important. Individually using one of them into input neurons can only provide satisfactory estimation. However, simultaneously using these two parameters into input neurons can give the best estimation. Thus, choosing suitable input parameters is more important than choosing multiple parameters.

Detecting, categorizing and forecasting large romps in wind farm power output using meteorological observations and WPPT

DEFF Research Database (Denmark)

Cutler, N.; Kay, M.; Jacka, K.

2007-01-01

The Wind Power Prediction Tool (WPPT) has been installed in Australia for the first time, to forecast the power output from the 65MW Roaring 40s Renewable Energy P/L Woolnorth Bluff Point wind form. This article analyses the general performance of WPPT as well as its performance during large romps...... (swings) in power output. In addition to this, detected large ramps are studied in detail and categorized. WPPT combines wind speed and direction forecasts from the Australian Bureau of Meteorology regional numerical weather prediction model, MesoLAPS, with real-time wind power observations to make hourly...... forecasts of the wind farm power output. The general performances of MesoLAPS and WPPTore evaluated over I year using the root mean square error (RMSE). The errors are significantly lower than for basic benchmark forecasts but higher than for many other WPPT installations, where the site conditions...

Wind Power Plant Control Optimisation with Incorporation of Wind Turbines and STATCOMs

DEFF Research Database (Denmark)

Petersen, Lennart; Kryezi, Fitim; Iov, Florin

2015-01-01

This paper addresses a detailed design and tuning of a wind power plant slope voltage control with reactive power contribution of wind turbines and STATCOMS. First, small-signal models of a single wind turbine and the whole wind power plant are developed, being appropriate for voltage control...... assessment. An exemplary wind power plant located in the United Kingdom and the corresponding grid code requirements are used as a base case. The final design and tuning process of the voltage controller results in a guidance, proposed for this particular control architecture. It provides qualitative...... outcomes regarding the impact of system delays, grid conditions and various operating conditions of the wind power plant, with and without incorporation of STATCOMS....

Dynamic Models for Wind Turbines and Wind Power Plants

Energy Technology Data Exchange (ETDEWEB)

Singh, M.; Santoso, S.

2011-10-01

The primary objective of this report was to develop universal manufacturer-independent wind turbine and wind power plant models that can be shared, used, and improved without any restrictions by project developers, manufacturers, and engineers. Manufacturer-specific models of wind turbines are favored for use in wind power interconnection studies. While they are detailed and accurate, their usages are limited to the terms of the non-disclosure agreement, thus stifling model sharing. The primary objective of the work proposed is to develop universal manufacturer-independent wind power plant models that can be shared, used, and improved without any restrictions by project developers, manufacturers, and engineers. Each of these models includes representations of general turbine aerodynamics, the mechanical drive-train, and the electrical characteristics of the generator and converter, as well as the control systems typically used. To determine how realistic model performance is, the performance of one of the models (doubly-fed induction generator model) has been validated using real-world wind power plant data. This work also documents selected applications of these models.

Data-driven wind plant control

NARCIS (Netherlands)

Gebraad, P.M.O.

2014-01-01

Each wind turbine in a cluster of wind turbines (a wind power plant) can influence the performance of other turbines through the wake that forms downstream of its rotor. The wake has a reduced wind velocity, since the turbine extracts energy from the flow, and the obstruction by the wind turbine

Comparison of Solar and Wind Power Output and Correlation with Real-Time Pricing

Science.gov (United States)

Hoepfl, Kathryn E.; Compaan, Alvin D.; Solocha, Andrew

2011-03-01

This study presents a method that can be used to determine the least volatile power output of a wind and solar hybrid energy system in which wind and solar systems have the same peak power. Hourly data for wind and PV systems in Northwest Ohio are used to show that a combination of both types of sustainable energy sources produces a more stable power output and would be more valuable to the grid than either individually. This method could be used to determine the ideal ratio in any part of the country and should help convince electric utility companies to bring more renewable generation online. This study also looks at real-time market pricing and how each system (solar, wind, and hybrid) correlates with 2009 hourly pricing from the Midwest Interconnect. KEH acknowledges support from the NSF-REU grant PHY-1004649 to the Univ. of Toledo and Garland Energy Systems/Ohio Department of Development.

Wind Plant Models in IEC 61400-27-2 and WECC - latest developments in international standards on wind turbine and wind plant modeling

DEFF Research Database (Denmark)

Fortmann, Jens; Miller, Nicholas; Kazachkov, Yuri

2015-01-01

This paper describes the latest developments in the standardization of wind plant and wind plant controller models. As a first step IEC TC88 WG 27 and WECC jointly developed generic wind turbine models which have been published by WECC in 2014 and IEC in 2015 as IEC 61400-27-1, which also include...

The Wind Integration National Dataset (WIND) toolkit (Presentation)

Energy Technology Data Exchange (ETDEWEB)

Caroline Draxl: NREL

2014-01-01

Regional wind integration studies require detailed wind power output data at many locations to perform simulations of how the power system will operate under high penetration scenarios. The wind datasets that serve as inputs into the study must realistically reflect the ramping characteristics, spatial and temporal correlations, and capacity factors of the simulated wind plants, as well as being time synchronized with available load profiles.As described in this presentation, the WIND Toolkit fulfills these requirements by providing a state-of-the-art national (US) wind resource, power production and forecast dataset.

Model for the techno-economic analysis of common work of wind power and CCGT power plant to offer constant level of power in the electricity market

Science.gov (United States)

Tomsic, Z.; Rajsl, I.; Filipovic, M.

2017-11-01

Wind power varies over time, mainly under the influence of meteorological fluctuations. The variations occur on all time scales. Understanding these variations and their predictability is of key importance for the integration and optimal utilization of wind in the power system. There are two major attributes of variable generation that notably impact the participation on power exchanges: Variability (the output of variable generation changes and resulting in fluctuations in the plant output on all time scales) and Uncertainty (the magnitude and timing of variable generation output is less predictable, wind power output has low levels of predictability). Because of these variability and uncertainty wind plants cannot participate to electricity market, especially to power exchanges. For this purpose, the paper presents techno-economic analysis of work of wind plants together with combined cycle gas turbine (CCGT) plant as support for offering continues power to electricity market. A model of wind farms and CCGT plant was developed in program PLEXOS based on real hourly input data and all characteristics of CCGT with especial analysis of techno-economic characteristics of different types of starts and stops of the plant. The Model analyzes the followings: costs of different start-stop characteristics (hot, warm, cold start-ups and shutdowns) and part load performance of CCGT. Besides the costs, the technical restrictions were considered such as start-up time depending on outage duration, minimum operation time, and minimum load or peaking capability. For calculation purposes, the following parameters are necessary to know in order to be able to economically evaluate changes in the start-up process: ramp up and down rate, time of start time reduction, fuel mass flow during start, electricity production during start, variable cost of start-up process, cost and charges for life time consumption for each start and start type, remuneration during start up time regarding

Output Power Control of Wind Turbine Generator by Pitch Angle Control using Minimum Variance Control

Science.gov (United States)

Senjyu, Tomonobu; Sakamoto, Ryosei; Urasaki, Naomitsu; Higa, Hiroki; Uezato, Katsumi; Funabashi, Toshihisa

In recent years, there have been problems such as exhaustion of fossil fuels, e. g., coal and oil, and environmental pollution resulting from consumption. Effective utilization of renewable energies such as wind energy is expected instead of the fossil fuel. Wind energy is not constant and windmill output is proportional to the cube of wind speed, which cause the generated power of wind turbine generators (WTGs) to fluctuate. In order to reduce fluctuating components, there is a method to control pitch angle of blades of the windmill. In this paper, output power leveling of wind turbine generator by pitch angle control using an adaptive control is proposed. A self-tuning regulator is used in adaptive control. The control input is determined by the minimum variance control. It is possible to compensate control input to alleviate generating power fluctuation with using proposed controller. The simulation results with using actual detailed model for wind power system show effectiveness of the proposed controller.

The effect of long-distance interconnection on wind power variability

International Nuclear Information System (INIS)

Fertig, Emily; Apt, Jay; Jaramillo, Paulina; Katzenstein, Warren

2012-01-01

We use time- and frequency-domain techniques to quantify the extent to which long-distance interconnection of wind plants in the United States would reduce the variability of wind power output. Previous work has shown that interconnection of just a few wind plants across moderate distances could greatly reduce the ratio of fast- to slow-ramping generators in the balancing portfolio. We find that interconnection of aggregate regional wind plants would not reduce this ratio further but would reduce variability at all frequencies examined. Further, interconnection of just a few wind plants reduces the average hourly change in power output, but interconnection across regions provides little further reduction. Interconnection also reduces the magnitude of low-probability step changes and doubles firm power output (capacity available at least 92% of the time) compared with a single region. First-order analysis indicates that balancing wind and providing firm power with local natural gas turbines would be more cost-effective than with transmission interconnection. For net load, increased wind capacity would require more balancing resources but in the same proportions by frequency as currently, justifying the practice of treating wind as negative load. (letter)

Vibrations of wind power plants; Schwingungen von Windenergieanlagen

Energy Technology Data Exchange (ETDEWEB)

NONE

2010-07-01

Within the meeting of the department vibration engineering of the Association of German Engineers (Duesseldorf, Federal Republic of Germany) between 3rd and 4th February, 2010 in Hanover (Federal Republic of Germany) the following lectures are presented: (1) Reduction of forced strengths generated by wagging and snaking of the rotor in the power strain of wind power plants (F. Mitsch); (2) Reduction of vibrations at wind power plants by means of active additional systems (S. Katz, S. Pankoke, N. Loix); (3) Reduction of vibrations by means of balancing and alignment (E. Becker, M. Kenzler); (4) Active absorber for reducing tonal emissions of vibration at wind power plants (R. Neugebauer, M. Linke, H. Kunze, M. Ulrich); (5) Control structures for damping torsion vibrations and peak loads in the power strain of wind power converters (C. Sourkounis); (6) Possibilities of a non-contact investigation of vibrations at wind power plants (R. Behrendt, E. Reimers, H. Wiegers); (7) Influences on the loadability of CMS statements (R. Wirth); (8) Recording modal structural properties with sensor grids and methods of operational modal analysis (A. Friedmann, D. Mayer, M. Koch, M. Kauba, T. Melz); (9) Early failure detection of damages of roller bearings in wind power gear units with variable speed (B. Hacke, G. Poll); (10) Condition monitoring in wind power plants - structure monitoring and life time monitoring of wind power plants (SCMS and LCMS) (H. Lange); (11) Development of a model-based structural health monitoring system for condition monitoring of rotor blades (C. Ebert, H. Friedmann, F.O. Henkel, B. Frankenstein, L. Schubert); (12) Efficient remote monitoring at wind power plants by means of an external diagnosis centre (G. Ceglarek); (13) Accurate turbine modelling at component and assembly level for durability and acoustic analysis (D. v. Werner, W. Hendricx); (14) Possibilities of the investigation of the dynamic behaviour of power strains in wind power plants by

Smoothing of Grid-connected Wind-Diesel Power Output Using Energy Capacitor System

Directory of Open Access Journals (Sweden)

Adel A. Elbaset

2014-06-01

Full Text Available This paper presents a small hybrid power system consists of two types of power generation; wind turbine and diesel generation, DG connected to power distribution system. The fluctuations like random nature of wind power, turbulent wind, and sudden changes in load demand create imbalances in power distribution that can affect the frequency and the voltage in the power system. So, addition of Energy capacitor System, ECS is useful for compensation of fluctuating power, since it is capable of controlling both active and reactive power simultaneously and can smooth the output power flow. Hence, this paper proposes herein a dynamic model and simulation of a grid connected wind/DG based-ECS with power flow controllers between load and generation. Moreover, the paper presents a study to analyze the leveling of output fluctuation of wind power with the installation of ECS. To control the power exchanged between the ECS system and the AC grid, a load Following Control, LFC based supervisor is proposed with the aim to minimize variations of the power generated by the diesel generator. The interesting performance of the proposed supervisor is shown with the help of simulations. The computer simulation program is confirmed on a realistic circuit model which implemented in the Simulink environment of Matlab and works as if on line.

Wind power plant system services

DEFF Research Database (Denmark)

Basit, Abdul; Altin, Müfit

Traditionally, conventional power plants have the task to support the power system, by supplying power balancing services. These services are required by the power system operators in order to secure a safe and reliable operation of the power system. However, as in the future the wind power...... is going more and more to replace conventional power plants, the sources of conventional reserve available to the system will be reduced and fewer conventional plants will be available on-line to share the regulation burden. The reliable operation of highly wind power integrated power system might...... then beat risk unless the wind power plants (WPPs) are able to support and participate in power balancing services. The objective of this PhD project is to develop and analyse control strategies which can increase the WPPs capability to provide system services, such as active power balancing control...

Understanding Dynamic Model Validation of a Wind Turbine Generator and a Wind Power Plant: Preprint

Energy Technology Data Exchange (ETDEWEB)

Muljadi, Eduard; Zhang, Ying Chen; Gevorgian, Vahan; Kosterev, Dmitry

2016-09-01

Regional reliability organizations require power plants to validate the dynamic models that represent them to ensure that power systems studies are performed to the best representation of the components installed. In the process of validating a wind power plant (WPP), one must be cognizant of the parameter settings of the wind turbine generators (WTGs) and the operational settings of the WPP. Validating the dynamic model of a WPP is required to be performed periodically. This is because the control parameters of the WTGs and the other supporting components within a WPP may be modified to comply with new grid codes or upgrades to the WTG controller with new capabilities developed by the turbine manufacturers or requested by the plant owners or operators. The diversity within a WPP affects the way we represent it in a model. Diversity within a WPP may be found in the way the WTGs are controlled, the wind resource, the layout of the WPP (electrical diversity), and the type of WTGs used. Each group of WTGs constitutes a significant portion of the output power of the WPP, and their unique and salient behaviors should be represented individually. The objective of this paper is to illustrate the process of dynamic model validations of WTGs and WPPs, the available data recorded that must be screened before it is used for the dynamic validations, and the assumptions made in the dynamic models of the WTG and WPP that must be understood. Without understanding the correct process, the validations may lead to the wrong representations of the WTG and WPP modeled.

Wind Plant Collector System Fault Protection and Coordination

Energy Technology Data Exchange (ETDEWEB)

Bradt, M. [IEEE PES Wind Plant Collector System Design Working Group; Behnke, M. R. [IEEE PES Wind Plant Collector System Design Working Group; Bloethe, W.G. [IEEE PES Wind Plant Collector System Design Working Group; Brooks, C. [IEEE PES Wind Plant Collector System Design Working Group; Camm, E H [IEEE PES Wind Plant Collector System Design Working Group; Dilling, W. [IEEE PES Wind Plant Collector System Design Working Group; Goltz, B. [IEEE PES Wind Plant Collector System Design Working Group; Li, J. [IEEE PES Wind Plant Collector System Design Working Group; Niemira, J. [IEEE PES Wind Plant Collector System Design Working Group; Nuckles, K. [IEEE PES Wind Plant Collector System Design Working Group; Patino, J. [IEEE PES Wind Plant Collector System Design Working Group; Reza, M [IEEE PES Wind Plant Collector System Design Working Group; Richardson, B. [IEEE PES Wind Plant Collector System Design Working Group; Samaan, N. [IEEE PES Wind Plant Collector System Design Working Group; Schoene, Jens [IEEE PES Wind Plant Collector System Design Working Group; Smith, Travis M [ORNL; Snyder, Isabelle B [ORNL; Starke, Michael R [ORNL; Walling, R. [IEEE PES Wind Plant Collector System Design Working Group; Zahalka, G. [IEEE PES Wind Plant Collector System Design Working Group

2010-01-01

This paper presents a summary of the most important protection and coordination considerations for wind power plants. Short-circuit characteristics of both aggregate wind plant and individual wind turbine genera- tors, as well as general interconnection protection requirements are discussed. Many factors such as security, reliability, and safety are considered for proper conservative protection of the wind power plant and individual turbines.

Towards a Reactive Power Oscillation Damping Controller for Wind Power Plant Based on Full Converter Wind Turbines

DEFF Research Database (Denmark)

Knüppel, Thyge; Kumar, Sathess; Thuring, Patrik

2012-01-01

In this paper a power oscillation damping controller (POD) based on modulation of reactive power (Q POD) is analyzed where the modular and distributed characteristics of the wind power plant (WPP) are considered. For a Q POD it is essential that the phase of the modulated output is tightly...... contributes to a collective response. This ability is shown with a 150 wind turbine (WT) WPP with all WTs represented, and it is demonstrated that the WPP contributes to the inter-area damping. The work is based on a nonlinear, dynamic model of the 3.6 MW Siemens Wind Power WT....... controlled to achieve a positive damping contribution. It is investigated how a park level voltage, reactive power, and power factor control at different grid strengths interact with the Q POD in terms of a resulting phase shift. A WPP is modular and distributed and a WPP Q POD necessitate that each WT...

ROBUST CONTROL ALGORITHM FOR MULTIVARIABLE PLANTS WITH QUANTIZED OUTPUT

Directory of Open Access Journals (Sweden)

A. A. Margun

2017-01-01

Full Text Available The paper deals with robust output control algorithm for multivariable plants under disturbances. A plant is described by the system of linear differential equations with known relative degrees. Plant parameters are unknown but belong to the known closed bounded set. Plant state vector is unmeasured. Plant output is measured only via static quantizer. Control system algorithm is based on the high gain feedback method. Developed controller provides exponential convergence of tracking error to the bounded area. The area bounds depend on quantizer parameters and the value of external disturbances. Experimental approbation of the proposed control algorithm is performed with the use of Twin Rotor MIMO System laboratory bench. This bench is a helicopter like model with two degrees of freedom (pitch and yaw. DC motors are used as actuators. The output signals are measured via optical encoders. Mathematical model of laboratory bench is obtained. Proposed algorithm was compared with proportional - integral – differential controller in conditions of output quantization. Obtained results have confirmed the efficiency of proposed controller.

Hybrid wind-power-distillation plant

Directory of Open Access Journals (Sweden)

Ninić Neven

2012-01-01

Full Text Available This paper reports and elaborates on the idea of a solar distiller and an offshore wind power plant operating together. The subject under discussion is a single-stage solar distillation plant with vaporization, using adiabatic expansion in the gravitational field inside a wind power plant supporting column. This scheme divides investment costs for electric power and distillate production. In the region of the Adriatic Sea, all electric power produced could be “converted” to hydrogen using less than 10% of the distillate produced.

Optimal control of wind power plants

NARCIS (Netherlands)

Steinbuch, M.; Boer, de W.W.; Bosgra, O.H.; Peeters, S.A.W.M.; Ploeg, J.

1988-01-01

The control system design for a wind power plant is investigated. Both theoverall wind farm control and the individual wind turbine control effect thewind farm dynamic performance.For a wind turbine with a synchronous generator and rectifier/invertersystem a multivariable controller is designed.

Control design for a wind turbine-generator using output feedback

Science.gov (United States)

Javid, S. H.; Murdoch, A.; Winkelman, J. R.

1981-01-01

The modeling and approach to control design for a large horizontal axis wind turbine (WT) generator are presented. The control design is based on a suboptimal output regulator which allows coordinated control of WT blade pitch angle and field voltage for the purposes of regulating electrical power and terminal voltage. Results of detailed non-linear simulation tests of this controller are shown.

Statistical Modeling of Large Wind Plant System's Generation - A Case Study

International Nuclear Information System (INIS)

Sabolic, D.

2014-01-01

This paper presents simplistic, yet very accurate, descriptive statistical models of various static and dynamic parameters of energy output from a large system of wind plants operated by Bonneville Power Administration (BPA), USA. The system's size at the end of 2013 was 4515 MW of installed capacity. The 5-minute readings from the beginning of 2007 to the end of 2013, recorded and published by BPA, were used to derive a number of experimental distributions, which were then used to devise theoretic statistical models with merely one or two parameters. In spite of the simplicity, they reproduced experimental data with great accuracy, which was checked by rigorous tests of goodness-of-fit. Statistical distribution functions were obtained for the following wind generation-related quantities: total generation as percentage of total installed capacity; change in total generation power in 5, 10, 15, 20, 25, 30, 45, and 60 minutes as percentage of total installed capacity; duration of intervals with total generated power, expressed as percentage of total installed capacity, lower than certain pre-specified level. Limitation of total installed wind plant capacity, when it is determined by regulation demand from wind plants, is discussed, too. The models presented here can be utilized in analyses related to power system economics/policy, which is also briefly discussed in the paper. (author).

Wind power plant in grid operation

International Nuclear Information System (INIS)

Heier, S.

1993-01-01

There are new prospects for electrical energy supply in coastal regions and on islands if one succeeds in integrating the available wind energy, dependent on the weather, into existing and to be developed supply structures. Apart from the supply of energy, effects on the grid and on the electrical consumer are gaining in importance. For wind power plants, the operating behaviour is appreciably determined by the electro-technical concept. The mechanical/electrical energy conversion with the corresponding grid connection and plant control play an important part here. Results of measurements and computer simulation make the differences in the behaviour of wind power plants clear. (orig.) [de

CFD Study on Aerodynamic Power Output Changes with Inter-Turbine Spacing Variation for a 6 MW Offshore Wind Farm

Directory of Open Access Journals (Sweden)

Nak Joon Choi

2014-11-01

Full Text Available This study examined the aerodynamic power output change of wind turbines with inter-turbine spacing variation for a 6 MW wind farm composed of three sets of 2 MW wind turbines using computational fluid dynamics (CFD. The wind farm layout design is becoming increasingly important as the use of wind energy is steadily increasing. Among the many wind farm layout design parameters, the inter-turbine spacing is a key factor in the initial investment cost, annual energy production and maintenance cost. The inter-turbine spacing should be determined to maximize the annual energy production and minimize the wake effect, turbulence effect and fatigue load during the service lifetime of wind turbines. Therefore, some compromise between the aerodynamic power output of wind turbines and the inter-turbine spacing is needed. An actuator disc model with the addition of a momentum source was not used, and instead, a full 3-dimensional model with a tower and nacelle was used for CFD analysis because of its great technical significance. The CFD analysis results, such as the aerodynamic power output, axial direction wind speed change, pressure drop across the rotor of wind turbine, and wind speed deficit due to the wake effect with inter-turbine spacing variation, were studied. The results of this study can be applied effectively to wind farm layout design and evaluation.

Review: Wind impacts on plant growth, mechanics and damage.

Science.gov (United States)

Gardiner, Barry; Berry, Peter; Moulia, Bruno

2016-04-01

Land plants have adapted to survive under a range of wind climates and this involve changes in chemical composition, physical structure and morphology at all scales from the cell to the whole plant. Under strong winds plants can re-orientate themselves, reconfigure their canopies, or shed needles, leaves and branches in order to reduce the drag. If the wind is too strong the plants oscillate until the roots or stem fail. The mechanisms of root and stem failure are very similar in different plants although the exact details of the failure may be different. Cereals and other herbaceous crops can often recover after wind damage and even woody plants can partially recovery if there is sufficient access to water and nutrients. Wind damage can have major economic impacts on crops, forests and urban trees. This can be reduced by management that is sensitive to the local site and climatic conditions and accounts for the ability of plants to acclimate to their local wind climate. Wind is also a major disturbance in many plant ecosystems and can play a crucial role in plant regeneration and the change of successional stage. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

Wind power scenario generation through state-space specifications for uncertainty analysis of wind power plants

International Nuclear Information System (INIS)

Díaz, Guzmán; Gómez-Aleixandre, Javier; Coto, José

2016-01-01

Highlights: • State space representations for simulating wind power plant output are proposed. • The representation of wind speed in state space allows structural analysis. • The joint model incorporates the temporal and spatial dependence structure. • The models are easily integrable into a backward/forward sweep algorithm. • Results evidence the remarkable differences between joint and marginal models. - Abstract: This paper proposes the use of state space models to generate scenarios for the analysis of wind power plant (WPP) generation capabilities. The proposal is rooted on the advantages that state space models present for dealing with stochastic processes; mainly their structural definition and the use of Kalman filter to naturally tackle some involved operations. The specification proposed in this paper comprises a structured representation of individual Box–Jenkins models, with indications about further improvements that can be easily performed. These marginal models are combined to form a joint model in which the dependence structure is easily handled. Indications about the procedure to calibrate and check the model, as well as a validation of its statistical appropriateness, are provided. Application of the proposed state space models provides insight on the need to properly specify the structural dependence between wind speeds. In this paper the joint and marginal models are smoothly integrated into a backward–forward sweep algorithm to determine the performance indicators (voltages and powers) of a WPP through simulation. As a result, visibly heavy tails emerge in the generated power probability distribution through the use of the joint model—incorporating a detailed description of the dependence structure—in contrast with the normally distributed power yielded by the margin-based model.

Wind Turbine and Wind Power Plant Modelling Aspects for Power System Stability Studies

DEFF Research Database (Denmark)

Altin, Müfit; Hansen, Anca Daniela; Göksu, Ömer

2014-01-01

Large amount of wind power installations introduce modeling challenges for power system operators at both the planning and operational stages of power systems. Depending on the scope of the study, the modeling details of the wind turbine or the wind power plant are required to be different. A wind...... turbine model which is developed for the short-term voltage stability studies can be inaccurate and sufficient for the frequency stability studies. Accordingly, a complete and detailed wind power plant model for every kind of study is not feasible in terms of the computational time and also...... and wind power plants are reviewed for power system stability studies. Important remarks of the models are presented by means of simulations to emphasize the impact of these modelling details on the power system....

Integrated monitoring of wind plant systems

Science.gov (United States)

Whelan, Matthew J.; Janoyan, Kerop D.; Qiu, Tong

2008-03-01

Wind power is a renewable source of energy that is quickly gaining acceptance by many. Advanced sensor technologies have currently focused solely on improving wind turbine rotor aerodynamics and increasing of the efficiency of the blade design and concentration. Alternatively, potential improvements in wind plant efficiency may be realized through reduction of reactionary losses of kinetic energy to the structural and substructural systems supporting the turbine mechanics. Investigation of the complete dynamic structural response of the wind plant is proposed using a large-scale, high-rate wireless sensor network. The wireless network enables sensors to be placed across the sizable structure, including the rotating blades, without consideration of cabling issues and the economic burden associated with large spools of measurement cables. A large array of multi-axis accelerometers is utilized to evaluate the modal properties of the system as well as individual members and would enable long-term structural condition monitoring of the wind turbine as well. Additionally, environmental parameters, including wind speed, temperature, and humidity, are wirelessly collected for correlation. Such a wireless system could be integrated with electrical monitoring sensors and actuators and incorporated into a remote multi-turbine centralized plant monitoring and control system.

Life cycle analysis of photovoltaic cell and wind power plants

International Nuclear Information System (INIS)

Uchiyama, Yohji

1997-01-01

The paper presents life cycle analyses of net energy and CO 2 emissions on photovoltaic cell and wind power generation plants. Energy requirements associated with a plant are estimated for producing materials, manufacturing equipment, constructing facilities, acid operating plants. Energy ratio and net supplied energy are calculated by the process energy analysis that examines the entire energy inventory of input and output during life time of a plant. Life cycle CO 2 emission can also be calculated from the energy requirements obtained by the net energy analysis. The emission also includes greenhouse effect equivalent to CO 2 emission of methane gas leakage at a mining as well as CO 2 emissions from fossil fuel combustion during generating electricity, natural gas treatment at an extracting well and cement production in industry. The commercially available and future-commercial technologies are dealt with in the study. Regarding PV technologies, two different kinds of installation are investigated; roof-top typed installation of residential houses and ground installation of electric utilities. (author)

Gridded Calibration of Ensemble Wind Vector Forecasts Using Ensemble Model Output Statistics

Science.gov (United States)

Lazarus, S. M.; Holman, B. P.; Splitt, M. E.

2017-12-01

A computationally efficient method is developed that performs gridded post processing of ensemble wind vector forecasts. An expansive set of idealized WRF model simulations are generated to provide physically consistent high resolution winds over a coastal domain characterized by an intricate land / water mask. Ensemble model output statistics (EMOS) is used to calibrate the ensemble wind vector forecasts at observation locations. The local EMOS predictive parameters (mean and variance) are then spread throughout the grid utilizing flow-dependent statistical relationships extracted from the downscaled WRF winds. Using data withdrawal and 28 east central Florida stations, the method is applied to one year of 24 h wind forecasts from the Global Ensemble Forecast System (GEFS). Compared to the raw GEFS, the approach improves both the deterministic and probabilistic forecast skill. Analysis of multivariate rank histograms indicate the post processed forecasts are calibrated. Two downscaling case studies are presented, a quiescent easterly flow event and a frontal passage. Strengths and weaknesses of the approach are presented and discussed.

Dynamic Frequency Response of Wind Power Plants

DEFF Research Database (Denmark)

Altin, Müfit

according to their grid codes. In these scenarios particularly with high wind power penetration cases, conventional power plants (CPPs) such as old thermal power plants are planned to be replaced with wind power plants (WPPs). Consequently, the power system stability will be affected and the control...... to maintain sustainable and reliable operation of the power system for these targets, transmission system operators (TSOs) have revised the grid code requirements. Also, the TSOs are planning the future development of the power system with various wind penetration scenarios to integrate more wind power...... capability of WPPs would be investigated. The objective of this project is to analyze and identify the power system requirements for the synchronizing power support and inertial response control of WPPs in high wind power penetration scenarios. The dynamic frequency response of WPPs is realized...

Wind Farm Active Power Dispatch for Output Power Maximizing Based on a Wind Turbine Control Strategy for Load Minimizing

DEFF Research Database (Denmark)

Zhang, Baohua; Hu, Weihao; Hou, Peng

2015-01-01

Inclusion of the wake effect in the wind farm control design (WF) can increase the total captured power by wind turbines (WTs), which is usually implemented by derating upwind WTs. However, derating the WT without a proper control strategy will increase the structural loads, caused by operation...... in stall mode. Therefore, the WT control strategy for derating operation should be considered in the attempt at maximizing the total captured power while reducing structural loads. Moreover, electrical power loss on the transmission system inside a WF is also not negligible for maximizing the total output...... power of the WF. In this paper, an optimal active power dispatch strategy based on a WT derating strategy and considering the transmission loss is proposed for maximizing the total output power. The active power reference of each WT is chosen as the optimization variable. A partial swarm optimizing...

IEA Wind Task 37: Systems Modeling Framework and Ontology for Wind Turbines and Plants

Energy Technology Data Exchange (ETDEWEB)

Dykes, Katherine L [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Zahle, Frederik [Technical University of Denmark; Merz, Karl [SINTEF Energy Research; McWilliam, Mike [Technical University of Denmark; Bortolotti, Pietro [Technical University Munich

2017-08-14

This presentation will provide an overview of progress to date in the development of a system modeling framework and ontology for wind turbines and plants as part of the larger IEA Wind Task 37 on wind energy systems engineering. The goals of the effort are to create a set of guidelines for a common conceptual architecture for wind turbines and plants so that practitioners can more easily share descriptions of wind turbines and plants across multiple parties and reduce the effort for translating descriptions between models; integrate different models together and collaborate on model development; and translate models among different levels of fidelity in the system.

Financing wind plants, taking leasing into special account

International Nuclear Information System (INIS)

Veltrup, M.

1993-01-01

Leasing cannot be managed without a special sort of external financing of wind power plants. Specifically for wind energy, it was found from an investigation of less than a year that an intended erection of a wind power plant should be carried out in the months of September or October, so that the autumn and winter months rich in energy can be used. For the erection of small wind power plants, it was found that taking advantage of the Investment Cost Grant is more sensible than the Operating Cost Grant. (orig./HW) [de

Inclusion of routine wind and turbulence forecasts in the Savannah River Plant's emergency response capabilities

International Nuclear Information System (INIS)

Pendergast, M.M.; Gilhousen, D.B.

1980-01-01

The Savannah River Plant's emergency response computer system was improved by the implementation of automatic forecasts of wind and turbulence for periods up to 30 hours. The forecasts include wind direction, wind speed, and horizontal and vertical turbulence intensity at 10, 91, and 243 m above ground for the SRP area, and were obtained by using the Model Output Statistics (MOS) technique. A technique was developed and tested to use the 30-hour MOS forecasts of wind and turbulence issued twice daily from the National Weather Service at Suitland, Maryland, into SRP's emergency response program. The technique for combining MOS forecasts, persistence, and adjusted-MOS forecast is used to generate good forecasts any time of day. Wind speed and turbulence forecasts have been shown to produce smaller root mean square errors (RMSE) than forecasts of persistence for time periods over about two hours. For wind direction, the adjusted-MOS forecasts produce smaller RMSE than persistence for times greater than four hours

Design and analysis of a hybrid renewable energy plant with solar and wind power

International Nuclear Information System (INIS)

Kabalci, Ersan

2013-01-01

Highlights: • A distributed generation system is developed with separate solar plant and wind turbine. • The solar plant is controlled with MPPT infrastructure of Perturb and Observe algorithm. • Power generation of source sites are converted to DC with PI controlled buck converters and collected on a DC busbar. • Harvested DC power is converted to AC with a full bridge inverter and SPWM control is performed in inverter. • The total harmonic distortion (THD) ratio of the generated 3-phase line is obtained in the limit of standards. - Abstract: A hybrid renewable energy plant that is based on solar and wind energy conversion systems is designed and analysed in this paper. Each separate energy conversion system is controlled either using regular PI controller or extended PI controller with an auxiliary controller containing Perturb and Observe algorithm. The solar plant model is constituted by connecting 170 W photovoltaic (PV) panels serially and energy conversion is performed with maximum power point tracking (MPPT) algorithm that controls the modulator of buck converter. The MPPT algorithm utilized in the control step of converter is developed using Perturb and Observe (P and O) that is extended with PI controller. The wind energy plant is designed with a permanent magnet synchronous generator (PMSG), and the AC–DC conversion stage is constituted with an uncontrolled full-bridge rectifier. All the converter outputs are connected to a busbar over interphase transformers (IPTs). The DC bus-bar voltage is supplied to a full bridge inverter to generate three-phase AC voltages at the output of inverter. The three-phase inverter is controlled with sinusoidal pulse width modulation (SPWM) scheme, which is developed with phase shifted carrier signals. The total harmonic distortion (THD) ratios are obtained at proper values according to international standards such as IEC61000 and IEEE 519-1992. Measurement results and obtained three phase voltage are analysed

Vibrations of wind power plants 2011; Schwingungen von Windenergieanlagen 2011

Energy Technology Data Exchange (ETDEWEB)

NONE

2011-07-01

Within the 2nd meeting of the VDI Wissensforum GmbH (Duesseldorf, Federal Republic of Germany) at 8th to 9th February, 2011 in Bremen (Federal Republic of Germany) the following lectures were held: (1) Are test bench measurements of wind gears comparable to field studies (T. Jacob); (2) Investigation of the dynamic behaviour of the drive train of wind power plants (T. Gellermann); (3) Noise source identification at wind power plants by means of microphone arrays with a special geometry (H. Kreidl); (4) Condition monitoring of rotor blades at wind power plants for the detection of damages at rotor blades, icy conditions and dynamic loads (P. Volkmer); (5) Analysis of the scale of damages at rolling bearings in wind power plants - In-depth methods of diagnosis and application of the diagnosis of rolling bearings at wind power plants according to the regulation VDI 3832 (D. Franke); (6) Investigation of acoustic emissions at wind power plants according to the regulation IEC 61400-11 and FGW - Presentation of a new integrated solution for the measuring technique (R. Schlombs); (7) Condition monitoring systems for wind power plants: State of the art and outlook for future developments from the view of the certification (K. Steingroever); (8) Refined vibration diagnostic methods for the condition monitoring at gears of wind power plants (R. Wirth); (9) Damage and self-healing of OWEA foundations (G. Gudehus); (10) Measurement of dynamic movements and condition monitoring at the fundaments of wind power plants beginning with the allocation of damage images till to the strengthening of fundaments (J. Nix); (11) Prediction of damages on wind power plant (P. Bangert); (12) Influence of a indirect converter on the operating characteristic of a power conversion system of wind power plants with a permanent magnet synchronous generator (C. Sourkounis); (13) Determination of realistic load assumptions for the pitch system and specification of a control strategy of a wind power

Effects of Wind on Virtual Plants in Animation

Directory of Open Access Journals (Sweden)

Tina L. M. Derzaph

2013-01-01

Full Text Available This paper presents the Growth-Flow method for animating the effect of wind on the motion and growth of virtual plant branches and leaves. The method incorporates changes to the growth rate when a plant is exposed to winds with speeds higher than a threshold. In particular, growth rate is reduced in branch elongation, increased in the branch radius, reduced in leaf length, and increased in leaf thickness. In addition, when a plant is exposed to wind for long time periods, the branch growth angle is changed to align more closely with the wind vector. The Growth-Flow method incorporates all these effects on growth and motion due to wind in one algorithm.

Local and regional effects of large scale atmospheric circulation patterns on winter wind power output in Western Europe

Science.gov (United States)

Zubiate, Laura; McDermott, Frank; Sweeney, Conor; O'Malley, Mark

2014-05-01

Recent studies (Brayshaw, 2009, Garcia-Bustamante, 2010, Garcia-Bustamante, 2013) have drawn attention to the sensitivity of wind speed distributions and likely wind energy power output in Western Europe to changes in low-frequency, large scale atmospheric circulation patterns such as the North Atlantic Oscillation (NAO). Wind speed variations and directional shifts as a function of the NAO state can be larger or smaller depending on the North Atlantic region that is considered. Wind speeds in Ireland and the UK for example are approximately 20 % higher during NAO + phases, and up to 30 % lower during NAO - phases relative to the long-term (30 year) climatological means. By contrast, in southern Europe, wind speeds are 15 % lower than average during NAO + phases and 15 % higher than average during NAO - phases. Crucially however, some regions such as Brittany in N.W. France have been identified in which there is negligible variability in wind speeds as a function of the NAO phase, as observed in the ERA-Interim 0.5 degree gridded reanalysis database. However, the magnitude of these effects on wind conditions is temporally and spatially non-stationary. As described by Comas-Bru and McDermott (2013) for temperature and precipitation, such non-stationarity is caused by the influence of two other patterns, the East Atlantic pattern, (EA), and the Scandinavian pattern, (SCA), which modulate the position of the NAO dipole. This phenomenon has also implications for wind speeds and directions, which has been assessed using the ERA-Interim reanalysis dataset and the indices obtained from the PC analysis of sea level pressure over the Atlantic region. In order to study the implications for power production, the interaction of the NAO and the other teleconnection patterns with local topography was also analysed, as well as how these interactions ultimately translate into wind power output. The objective is to have a better defined relationship between wind speed and power

VAr reserve concept applied to a wind power plant

DEFF Research Database (Denmark)

Martinez, Jorge; Kjær, Philip C.; Rodriguez, Pedro

2011-01-01

to wind power plants. This paper proposes two different VAr reserve control strategies for a wind power plant. The amount of dynamic VAr available most of the operation time, makes the wind power plant (WPP) a good candidate to include a VAr reserve management system. Two different ways of implementing...... a VAr management system are proposed and analyzed. Such a reactive power reserve may be provided by the wind power plant since the amount of reactive power installed for most active power working points exceeds the demand required by the grid operator. Basically, this overrated reactive power capacity...... is a consequence of sizing wind turbine facilities for maximum active power level. The reactive power losses, due to active power transportation inside the plant (normally two transformers), and P-Q wind turbine characteristics define the P-Q reserve chart. By utilizing the intrinsic overrated reactive power...

Limiting conditions for nuclear power plant competitiveness vs. fossil and wind plants

International Nuclear Information System (INIS)

Feretic, Danilo; Cavlina, Nikola

2010-01-01

The aim of this paper is to compare potential energy options for future electricity generation. The paper considers comparison of discounted total cost of electricity generated by nuclear power plant and by combined natural gas and wind plants, having in total equal electricity generation. Large uncertainty in the future fuel costs makes planning of optimal power generating mix very difficult to justify. Probabilistic method is used in the analysis which allows inclusion of uncertainties in future electricity generating cost prediction. Additionally, an informative functional relation between nuclear plant investment cost, natural gas price and wind plant efficiency, that determines competitive power generation between considered options, is also shown. Limiting conditions for nuclear power plant competitiveness vs. fossil and wind plants are presented. (authors)

A quantitative approach to wind farm diversification and reliability

Energy Technology Data Exchange (ETDEWEB)

Degeilh, Yannick; Singh, Chanan [Department of Electrical and Computer Engineering, Texas A and M University, College Station, TX 77843 (United States)

2011-02-15

This paper proposes a general planning method to minimize the variance of aggregated wind farm power output by optimally distributing a predetermined number of wind turbines over a preselected number of potential wind farming sites. The objective is to facilitate high wind power penetration through the search for steadier overall power output. Another optimization formulation that takes into account the correlations between wind power outputs and load is also presented. Three years of wind data from the recent NREL/3TIER study in the western US provides the statistics for evaluating each site upon their mean power output, variance and correlation with each other so that the best allocations can be determined. The reliability study reported in this paper investigates the impact of wind power output variance reduction on a power system composed of a virtual wind power plant and a load modeled from the 1996 IEEE RTS. Some traditional reliability indices such as the LOLP are calculated and it is eventually shown that configurations featuring minimal global power output variances generally prove the most reliable provided the sites are not significantly correlated with the modeled load. Consequently, the choice of uncorrelated/negatively correlated sites is favored. (author)

A quantitative approach to wind farm diversification and reliability

International Nuclear Information System (INIS)

Degeilh, Yannick; Singh, Chanan

2011-01-01

This paper proposes a general planning method to minimize the variance of aggregated wind farm power output by optimally distributing a predetermined number of wind turbines over a preselected number of potential wind farming sites. The objective is to facilitate high wind power penetration through the search for steadier overall power output. Another optimization formulation that takes into account the correlations between wind power outputs and load is also presented. Three years of wind data from the recent NREL/3TIER study in the western US provides the statistics for evaluating each site upon their mean power output, variance and correlation with each other so that the best allocations can be determined. The reliability study reported in this paper investigates the impact of wind power output variance reduction on a power system composed of a virtual wind power plant and a load modeled from the 1996 IEEE RTS. Some traditional reliability indices such as the LOLP are calculated and it is eventually shown that configurations featuring minimal global power output variances generally prove the most reliable provided the sites are not significantly correlated with the modeled load. Consequently, the choice of uncorrelated/negatively correlated sites is favored. (author)

Advancements in Wind Integration Study Data Modeling: The Wind Integration National Dataset (WIND) Toolkit; Preprint

Energy Technology Data Exchange (ETDEWEB)

Draxl, C.; Hodge, B. M.; Orwig, K.; Jones, W.; Searight, K.; Getman, D.; Harrold, S.; McCaa, J.; Cline, J.; Clark, C.

2013-10-01

Regional wind integration studies in the United States require detailed wind power output data at many locations to perform simulations of how the power system will operate under high-penetration scenarios. The wind data sets that serve as inputs into the study must realistically reflect the ramping characteristics, spatial and temporal correlations, and capacity factors of the simulated wind plants, as well as be time synchronized with available load profiles. The Wind Integration National Dataset (WIND) Toolkit described in this paper fulfills these requirements. A wind resource dataset, wind power production time series, and simulated forecasts from a numerical weather prediction model run on a nationwide 2-km grid at 5-min resolution will be made publicly available for more than 110,000 onshore and offshore wind power production sites.

Study of Interdependence of Wind Generation Output and Potential PV Generation in the Area of ENERGA-OPERATOR SA

Directory of Open Access Journals (Sweden)

Michał Bajor

2016-09-01

Full Text Available This paper presents the results of an analysis of the interdependence of wind generation output and photovoltaic generation potential in the ENERGA-OPERATOR SA grid. The first study of the interdependence of these two types of renewable sources’ generation outputs was carried out by the Gdańsk Branch of the Institute of Power Engineering in cooperation with ENERGA-OPERATOR in 2012. An important conclusion of the study was the need to repeat the analysis for a larger set of input data as the study covered the period of one year only, and for obvious reasons a limited number of wind farms. The present study’s inputs included a period of four years and more wind farms, due to the continuous connecting of new facilities to the grid. Thus, the results are characterized by a much higher level of credibility, and allow drawing mor correct conclusions regarding the analysed interdependence. The research on the interdependence of the annual wind generation output and potential generation from photovoltaic sources indicates that both generation types are characterized by mutual spatio-temporal dependency. In the study the relationship was quantified by evaluation of the maximum actual wind generation output in specific areas in the case of high PV generation output in a given area and vice versa. The results may allow for appropriate (i.e. substantiating the modelled operating conditions of the system in relation to reality consideration of both types of sources in various types of system analyses of their impact on the grid performance, such as interconnection studies for new sources and distribution grid development planning.

Wind Power: Building and Connecting Large Wind Power Plants; Vindkraft: bygga och ansluta stoerre vindkraftverk

Energy Technology Data Exchange (ETDEWEB)

2007-09-15

This brochure is written for those who want to build a large wind power plant (1 MW or more) or wind power parks. It describes the process from idea to completed plant. A review of environmental impacts of wind power is also included

A neural network approach to local downscaling of GCM output for assessing wind power implications of climate change

International Nuclear Information System (INIS)

Sailor, D.J.; Hu, T.; Li, X.; Rosen, J.N.

2000-01-01

A methodology is presented for downscaling General Circulation Model (GCM) output to predict surface wind speeds at scales of interest in the wind power industry under expected future climatic conditions. The approach involves a combination of Neural Network tools and traditional weather forecasting techniques. A Neural Network transfer function is developed to relate local wind speed observations to large scale GCM predictions of atmospheric properties under current climatic conditions. By assuming the invariability of this transfer function under conditions of doubled atmospheric carbon dioxide, the resulting transfer function is then applied to GCM output for a transient run of the National Center for Atmospheric Research coupled ocean-atmosphere GCM. This methodology is applied to three test sites in regions relevant to the wind power industry - one in Texas and two in California. Changes in daily mean wind speeds at each location are presented and discussed with respect to potential implications for wind power generation. (author)

Wind data for wind driven plant. [site selection for optimal performance

Science.gov (United States)

Stodhart, A. H.

1973-01-01

Simple, averaged wind velocity data provide information on energy availability, facilitate generator site selection and enable appropriate operating ranges to be established for windpowered plants. They also provide a basis for the prediction of extreme wind speeds.

Wind Plant Performance Prediction (WP3) Project

Energy Technology Data Exchange (ETDEWEB)

Craig, Anna [National Renewable Energy Laboratory (NREL), Golden, CO (United States)

2018-01-26

The methods for analysis of operational wind plant data are highly variable across the wind industry, leading to high uncertainties in the validation and bias-correction of preconstruction energy estimation methods. Lack of credibility in the preconstruction energy estimates leads to significant impacts on project financing and therefore the final levelized cost of energy for the plant. In this work, the variation in the evaluation of a wind plant's operational energy production as a result of variations in the processing methods applied to the operational data is examined. Preliminary results indicate that selection of the filters applied to the data and the filter parameters can have significant impacts in the final computed assessment metrics.

Implementation of a Model Output Statistics based on meteorological variable screening for short‐term wind power forecast

DEFF Research Database (Denmark)

Ranaboldo, Matteo; Giebel, Gregor; Codina, Bernat

2013-01-01

A combination of physical and statistical treatments to post‐process numerical weather predictions (NWP) outputs is needed for successful short‐term wind power forecasts. One of the most promising and effective approaches for statistical treatment is the Model Output Statistics (MOS) technique....... The proposed MOS performed well in both wind farms, and its forecasts compare positively with an actual operative model in use at Risø DTU and other MOS types, showing minimum BIAS and improving NWP power forecast of around 15% in terms of root mean square error. Further improvements could be obtained...

Harmonics in a Wind Power Plant: Preprint

Energy Technology Data Exchange (ETDEWEB)

Preciado, V.; Madrigal, M.; Muljadi, E.; Gevorgian, V.

2015-04-02

Wind power generation has been growing at a very fast pace for the past decade, and its influence and impact on the electric power grid is significant. As in a conventional power plant, a wind power plant (WPP) must ensure that the quality of the power being delivered to the grid is excellent. At the same time, the wind turbine should be able to operate immune to small disturbances coming from the grid. Harmonics are one of the more common power quality issues presented by large WPPs because of the high switching frequency of the power converters and the possible nonlinear behavior from electric machines (generator, transformer, reactors) within a power plant. This paper presents a summary of the most important issues related to harmonics in WPPs and discusses practical experiences with actual Type 1 and Type 3 wind turbines in two WPPs.

FACTS Devices for Large Wind Power Plants

DEFF Research Database (Denmark)

Adamczyk, Andrzej Grzegorz; Teodorescu, Remus; Rodriguez, Pedro

2010-01-01

Growing number of wind turbines is changing electricity generation profile all over the world. However, high wind energy penetration affects power system safety and stability. For this reason transmission system operators (TSO) impose more stringent connection requirements on the wind power plant...

Influence of the level of fit of a density probability function to wind-speed data on the WECS mean power output estimation

International Nuclear Information System (INIS)

Carta, Jose A.; Ramirez, Penelope; Velazquez, Sergio

2008-01-01

Static methods which are based on statistical techniques to estimate the mean power output of a WECS (wind energy conversion system) have been widely employed in the scientific literature related to wind energy. In the static method which we use in this paper, for a given wind regime probability distribution function and a known WECS power curve, the mean power output of a WECS is obtained by resolving the integral, usually using numerical evaluation techniques, of the product of these two functions. In this paper an analysis is made of the influence of the level of fit between an empirical probability density function of a sample of wind speeds and the probability density function of the adjusted theoretical model on the relative error ε made in the estimation of the mean annual power output of a WECS. The mean power output calculated through the use of a quasi-dynamic or chronological method, that is to say using time-series of wind speed data and the power versus wind speed characteristic of the wind turbine, serves as the reference. The suitability of the distributions is judged from the adjusted R 2 statistic (R a 2 ). Hourly mean wind speeds recorded at 16 weather stations located in the Canarian Archipelago, an extensive catalogue of wind-speed probability models and two wind turbines of 330 and 800 kW rated power are used in this paper. Among the general conclusions obtained, the following can be pointed out: (a) that the R a 2 statistic might be useful as an initial gross indicator of the relative error made in the mean annual power output estimation of a WECS when a probabilistic method is employed; (b) the relative errors tend to decrease, in accordance with a trend line defined by a second-order polynomial, as R a 2 increases

Hurricane Resilient Wind Plant Concept Study Final Report

Energy Technology Data Exchange (ETDEWEB)

Dibra, Besart [Keystone Engineering Inc., Vonore, TN (United States); Finucane, Zachary [Keystone Engineering Inc., Vonore, TN (United States); Foley, Benjamin [Keystone Engineering Inc., Vonore, TN (United States); Hall, Rudy [Keystone Engineering Inc., Vonore, TN (United States); Damiani, Rick [National Renewable Energy Lab. (NREL), Golden, CO (United States); Maples, Benjamin [National Renewable Energy Lab. (NREL), Golden, CO (United States); Parker, Zachary [National Renewable Energy Lab. (NREL), Golden, CO (United States); Robertson, Amy [National Renewable Energy Lab. (NREL), Golden, CO (United States); Scott, George [National Renewable Energy Lab. (NREL), Golden, CO (United States); Stehly, Tyler [National Renewable Energy Lab. (NREL), Golden, CO (United States); Wendt, Fabian [National Renewable Energy Lab. (NREL), Golden, CO (United States); Andersen, Mads Boel Overgaard [Siemens Wind Power A/S, Brande (Denmark); Standish, Kevin [Siemens Wind Power A/S, Brande (Denmark); Lee, Ken [Wetzel Engineering Inc., Round Rock, TX (United States); Raina, Amool [Wetzel Engineering Inc., Round Rock, TX (United States); Wetzel, Kyle [Wetzel Engineering Inc., Round Rock, TX (United States); Musial, Walter [National Renewable Energy Lab. (NREL), Golden, CO (United States); Schreck, Scott [National Renewable Energy Lab. (NREL), Golden, CO (United States)

2016-10-01

Hurricanes occur over much of the U.S. Atlantic and Gulf coasts, from Long Island to the U.S.-Mexico border, encompassing much of the nation's primary offshore wind resource. Category 5 hurricanes have made landfall as far north as North Carolina, with Category 3 hurricanes reaching New York with some frequency. Along the US West coast, typhoons strike with similar frequency and severity. At present, offshore wind turbine design practices do not fully consider the severe operating conditions imposed by hurricanes. Although universally applied to most turbine designs, International Electrotechnical Commission (IEC) standards do not sufficiently address the duration, directionality, magnitude, or character of hurricanes. To assess advanced design features that could mitigate hurricane loading in various ways, this Hurricane-Resilient Wind Plant Concept Study considered a concept design study of a 500-megawatt (MW) wind power plant consisting of 10-MW wind turbines deployed in 25-meter (m) water depths in the Western Gulf of Mexico. This location was selected because hurricane frequency and severity provided a unique set of design challenges that would enable assessment of hurricane risk and projection of cost of energy (COE) changes, all in response to specific U.S. Department of Energy (DOE) objectives. Notably, the concept study pursued a holistic approach that incorporated multiple advanced system elements at the wind turbine and wind power plant levels to meet objectives for system performance and reduced COE. Principal turbine system elements included a 10-MW rotor with structurally efficient, low-solidity blades; a lightweight, permanent-magnet, direct-drive generator, and an innovative fixed substructure. At the wind power plant level, turbines were arrayed in a large-scale wind power plant in a manner aimed at balancing energy production against capital, installation, and operation and maintenance (O&M) costs to achieve significant overall reductions in

Wind tower with vertical rotors

Energy Technology Data Exchange (ETDEWEB)

Dietz, A

1978-08-03

The invention concerns a wind tower with vertical rotors. A characteristic is that the useful output of the rotors is increased by the wind pressure, which is guided to the rotors at the central opening and over the whole height of the structure by duct slots in the inner cells. These duct slots start behind the front nose of the inner cell and lead via the transverse axis of the pillar at an angle into the space between the inner cells and the cell body. This measure appreciably increases the useful output of the rotors, as the rotors do not have to provide any displacement work from their output, but receive additional thrust. The wind pressure pressing from inside the rotor and accelerating from the outside produces a better outflow of the wind from the power plant pillar with only small tendency to turbulence, which appreciably improves the effect of the adjustable turbulence smoothers, which are situated below the rotors over the whole height.

Noise from wind power plants

International Nuclear Information System (INIS)

Ljunggren, S.

2001-12-01

First, the generation of noise at wind power plants and the character of the sound is described. The propagation of the sound and its dependence on the structure of the ground and on wind and temperature is treated next. Models for calculation of the noise emission are reviewed and examples of applications are given. Different means for reducing the disturbances are described

Introducing WISDEM:An Integrated System Modeling for Wind Turbines and Plant (Presentation)

Energy Technology Data Exchange (ETDEWEB)

Dykes, K.; Graf, P.; Scott, G.; Ning, A.; King, R.; Guo, Y.; Parsons, T.; Damiani, R.; Felker, F.; Veers, P.

2015-01-01

The National Wind Technology Center wind energy systems engineering initiative has developed an analysis platform to leverage its research capabilities toward integrating wind energy engineering and cost models across wind plants. This Wind-Plant Integrated System Design & Engineering Model (WISDEM) platform captures the important interactions between various subsystems to achieve a better National Wind Technology Center wind energy systems engineering initiative has developed an analysis platform to leverage its research capabilities toward integrating wind energy engineering and cost models across wind plants. This Wind-Plant Integrated System Design & Engineering Model (WISDEM) platform captures the important interactions between various subsystems to achieve a better understanding of how to improve system-level performance and achieve system-level cost reductions. This work illustrates a few case studies with WISDEM that focus on the design and analysis of wind turbines and plants at different system levels.

Methodology for Assessment of Inertial Response from Wind Power Plants

DEFF Research Database (Denmark)

Altin, Müfit; Teodorescu, Remus; Bak-Jensen, Birgitte

2012-01-01

High wind power penetration levels result in additional requirements from wind power in order to improve frequency stability. Replacement of conventional power plants with wind power plants reduces the power system inertia due to the wind turbine technology. Consequently, the rate of change...... of frequency and the maximum frequency deviation increase after a disturbance such as generation loss, load increase, etc. Having no inherent inertial response, wind power plants need additional control concepts in order to provide an additional active power following a disturbance. Several control concepts...... have been implemented in the literature, but the assessment of these control concepts with respect to power system requirements has not been specified. In this paper, a methodology to assess the inertial response from wind power plants is proposed. Accordingly, the proposed methodology is applied...

A new self-scheduling strategy for integrated operation of wind and pumped-storage power plants in power markets

International Nuclear Information System (INIS)

Varkani, Ali Karimi; Daraeepour, Ali; Monsef, Hassan

2011-01-01

Highlights: → A strategy for integrated operation of wind and pumped-storage plants is proposed. → Participation of both plants in energy and ancillary service markets is modeled. → The uncertainty of wind production is modeled by a novel probabilistic function. → The proposed strategy is tested on a real case in the Spanish electricity market. -- Abstract: Competitive structure of power markets causes various challenges for wind resources to participate in these markets. Indeed, production uncertainty is the main cause of their low income. Thus, they are usually supported by system operators, which is in contrast with the competitive paradigm of power markets. In this paper, a new strategy for increasing the profits of wind resources is proposed. In the suggested strategy, a Generation Company (GenCo), who owns both wind and pumped-storage plants, self-schedules the integrated operation of them regarding the uncertainty of wind power generation. For presenting an integrated self-schedule and obtaining a real added value of the strategy, participation of the GenCo in energy and ancillary service markets is modeled. The self-scheduling strategy is based on stochastic programming techniques. Outputs of the problem include generation offers in day-ahead energy market and ancillary service markets, including spinning and regulation reserve markets. A Neural Network (NN) based technique is used for modeling the uncertainty of wind power production. The proposed strategy is tested on a real wind farm in mainland, Spain. Moreover, added value of the strategy is presented in different conditions of the market.

Wind/Hybrid Electricity Applications

Energy Technology Data Exchange (ETDEWEB)

McDaniel, Lori [Iowa Department of Natural Resources, Des Moines, IA (United States)

2001-03-01

Wind energy is widely recognized as the most efficient and cost effective form of new renewable energy available in the Midwest. New utility-scale wind farms (arrays of large turbines in high wind areas producing sufficient energy to serve thousands of homes) rival the cost of building new conventional forms of combustion energy plants, gas, diesel and coal power plants. Wind energy is not subject to the inflationary cost of fossil fuels. Wind energy can also be very attractive to residential and commercial electric customers in high wind areas who would like to be more self-sufficient for their energy needs. And wind energy is friendly to the environment at a time when there is increasing concern about pollution and climate change. However, wind energy is an intermittent source of power. Most wind turbines start producing small amounts of electricity at about 8-10 mph (4 meters per second) of wind speed. The turbine does not reach its rated output until the wind reaches about 26-28 mph (12 m/s). So what do you do for power when the output of the wind turbine is not sufficient to meet the demand for energy? This paper will discuss wind hybrid technology options that mix wind with other power sources and storage devices to help solve this problem. This will be done on a variety of scales on the impact of wind energy on the utility system as a whole, and on the commercial and small-scale residential applications. The average cost and cost-benefit of each application along with references to manufacturers will be given. Emerging technologies that promise to shape the future of renewable energy will be explored as well.

Wind Power Plant Grounding, Overvoltage Protection, and Insulation Coordination

Energy Technology Data Exchange (ETDEWEB)

Camm, E H [IEEE PES Wind Plant Collector System Design Working Group; Behnke, M. R. [IEEE PES Wind Plant Collector System Design Working Group; Bolado, O. [IEEE PES Wind Plant Collector System Design Working Group; Bollen, M. [IEEE PES Wind Plant Collector System Design Working Group; Bradt, M. [IEEE PES Wind Plant Collector System Design Working Group; Brooks, C. [IEEE PES Wind Plant Collector System Design Working Group; Dilling, W. [IEEE PES Wind Plant Collector System Design Working Group; Edds, M. [IEEE PES Wind Plant Collector System Design Working Group; Hejdak, W. J. [IEEE PES Wind Plant Collector System Design Working Group; Houseman, D. [IEEE PES Wind Plant Collector System Design Working Group; Klein, S. [IEEE PES Wind Plant Collector System Design Working Group; Li, Fangxing [ORNL; Li, J. [IEEE PES Wind Plant Collector System Design Working Group; Maibach, P. [IEEE PES Wind Plant Collector System Design Working Group; Nicolai, T. [IEEE PES Wind Plant Collector System Design Working Group; Pasupulati, S. V. [IEEE PES Wind Plant Collector System Design Working Group; Patino, J. [IEEE PES Wind Plant Collector System Design Working Group; Samaan, N. [IEEE PES Wind Plant Collector System Design Working Group; Saylors, S. [IEEE PES Wind Plant Collector System Design Working Group; Siebert, T. [IEEE PES Wind Plant Collector System Design Working Group; Smith, Travis M [ORNL; Starke, Michael R [ORNL; Walling, R. [IEEE PES Wind Plant Collector System Design Working Group

2009-01-01

Proper insulation coordination is critical to achieving expected life from wind plant equipment. The collector systems of large wind plants require the application of surge arresters to protect the equipment insulation from transient overvoltages. The application of surge arresters is constrained by maximum operating and temporary overvoltage levels. This paper provides a tutorial description of the process of selecting and applying surge arresters to wind plant medium voltage collector systems, with emphasis on the peculiar properties of this application.

Operating of Small Wind Power Plants with Induction Generators

OpenAIRE

Jakub Nevrala; Stanislav Misak

2008-01-01

This paper describes different systems of small wind power plants with induction generators used in the Czech Republic. Problems of wind power plants running with induction generators are solved within partial target of the research project MSM 6198910007. For small wind power plants is used induction motor as a generator. Parameters of the name plate of motor must be resolved for generator running on measuring base. These generators are running as a separately working generators or generator...

Distributed Low-Complexity Controller for Wind Power Plant in Derated Operation

DEFF Research Database (Denmark)

Biegel, Benjamin; Madjidian, Daria; Spudic, Vedrana

2013-01-01

We consider a wind power plant of megawatt wind turbines operating in derated mode. When operating in this mode, the wind power plant controller is free to distribute power set-points to the individual turbines, as long as the total power demand is met. In this work, we design a controller...... that exploits this freedom to reduce the fatigue on the turbines in the wind power plant. We show that the controller can be designed in a decentralized manner, such that each wind turbine is equipped with a local low-complexity controller relying only on few measurements and little communication. As a basis...... for the controller design, a linear wind turbine model is constructed and verified in an operational wind power plant of megawatt turbines. Due to limitations of the wind power plant available for tests, it is not possible to implement the developed controller; instead the final distributed controller is evaluated...

Wind Power Plants Fundamentals, Design, Construction and Operation

CERN Document Server

Twele, Jochen

2012-01-01

Wind power plants teaches the physical foundations of usage of Wind Power. It includes the areas like Construction of Wind Power Plants, Design, Development of Production Series, Control, and discusses the dynamic forces acting on the systems as well as the power conversion and its connection to the distribution system. The book is written for graduate students, practitioners and inquisitive readers of any kind. It is based on lectures held at several universities. Its German version it already is the standard text book for courses on Wind Energy Engineering but serves also as reference for practising engineers.

Design and Tuning of Wind Power Plant Voltage Controller with Embedded Application of Wind Turbines and STATCOMs

DEFF Research Database (Denmark)

Petersen, Lennart; Kryezi, Fitim; Iov, Florin

2017-01-01

This study addresses a detailed design and tuning of a wind power plant voltage control with reactive power contribution of wind turbines and static synchronous compensators (STATCOMs). First, small-signal models of a single wind turbine and STATCOM are derived by using the state-space approach....... A complete phasor model of the entire wind power plant is constructed, being appropriate for voltage control assessment. An exemplary wind power plant located in the United Kingdom and the corresponding grid code requirements are used as a base case. The final design and tuning process of the voltage...... controller results in a guidance, proposed for this particular control architecture. It provides qualitative outcomes regarding the parametrisation of each individual control loop and how to adjust the voltage controller depending on different grid stiffnesses of the wind power plant connection...

Influence of the level of fit of a density probability function to wind-speed data on the WECS mean power output estimation

Energy Technology Data Exchange (ETDEWEB)

Carta, Jose A. [Department of Mechanical Engineering, University of Las Palmas de Gran Canaria, Campus de Tafira s/n, 35017 Las Palmas de Gran Canaria, Canary Islands (Spain); Ramirez, Penelope; Velazquez, Sergio [Department of Renewable Energies, Technological Institute of the Canary Islands, Pozo Izquierdo Beach s/n, 35119 Santa Lucia, Gran Canaria, Canary Islands (Spain)

2008-10-15

Static methods which are based on statistical techniques to estimate the mean power output of a WECS (wind energy conversion system) have been widely employed in the scientific literature related to wind energy. In the static method which we use in this paper, for a given wind regime probability distribution function and a known WECS power curve, the mean power output of a WECS is obtained by resolving the integral, usually using numerical evaluation techniques, of the product of these two functions. In this paper an analysis is made of the influence of the level of fit between an empirical probability density function of a sample of wind speeds and the probability density function of the adjusted theoretical model on the relative error {epsilon} made in the estimation of the mean annual power output of a WECS. The mean power output calculated through the use of a quasi-dynamic or chronological method, that is to say using time-series of wind speed data and the power versus wind speed characteristic of the wind turbine, serves as the reference. The suitability of the distributions is judged from the adjusted R{sup 2} statistic (R{sub a}{sup 2}). Hourly mean wind speeds recorded at 16 weather stations located in the Canarian Archipelago, an extensive catalogue of wind-speed probability models and two wind turbines of 330 and 800 kW rated power are used in this paper. Among the general conclusions obtained, the following can be pointed out: (a) that the R{sub a}{sup 2} statistic might be useful as an initial gross indicator of the relative error made in the mean annual power output estimation of a WECS when a probabilistic method is employed; (b) the relative errors tend to decrease, in accordance with a trend line defined by a second-order polynomial, as R{sub a}{sup 2} increases. (author)

Analysis of an inverter-supplied multi-winding transformer with a full-wave rectifier at the output

International Nuclear Information System (INIS)

Klopcic, Beno; Dolinar, Drago; Stumberger, Gorazd

2008-01-01

This paper deals with the magnetic analysis of an inverter-supplied multi-winding transformer frequently used in resistance spot welding applications. The basic structure of the analyzed system consists of an inverter, a single-phase transformer with two secondary windings and a full-wave rectifier mounted at the output of the transformer, which assure a very short rise time of the welding current. The disturbing current spikes often appear in the transformer's primary in the steady-state operation, which can activate the over-current protection switch-off of the system. The results of numerical analysis performed on the nonlinear model of the discussed system have shown that very strong magnetic saturation of the transformer's iron core, caused by the interaction among the different ohmic resistances of secondary windings and different characteristics of the output rectifier diodes, provokes unwanted current spikes. Magnetic saturation could be efficiently eliminated using very simple passive method proposed in this paper. All findings are confirmed by systematic analysis numerically and experimentally

Innovative Offshore Wind Plant Design Study

Energy Technology Data Exchange (ETDEWEB)

Hurley, William L. [Glosten Associates, Inc., Seattle, WA (United States); Nordstrom, Charles J. [Glosten Associates, Inc., Seattle, WA (United States); Morrison, Brent J. [Glosten Associates, Inc., Seattle, WA (United States)

2013-12-18

Technological advancements in the Glosten PelaStar floating wind turbine system have led to projected cost of energy (COE) reductions from today’s best-in-class offshore wind systems. The PelaStar system is projected to deliver a COE that is 35% lower than that delivered by the current offshore wind plants. Several technology developments have been achieved that directly target significant cost of energy reductions. These include: Application of state-of-the-art steel construction materials and methods, including fatigue-resistant welding techniques and technologies, to reduce hull steel weight; Advancements in synthetic fiber tendon design for the mooring system, which are made possible by laboratory analysis of full-scale sub-rope specimens; Investigations into selected anchor technologies to improve anchor installation methods; Refinement of the installation method, specifically through development of the PelaStar Support Barge design. Together, these technology developments drive down the capital cost and operating cost of offshore wind plants and enable access to superb wind resources in deep water locations. These technology developments also reduce the uncertainty of the PelaStar system costs, which increases confidence in the projected COE reductions.

Possible Power Estimation of Down-Regulated Offshore Wind Power Plants

DEFF Research Database (Denmark)

Gögmen, Tuhfe

The penetration of offshore wind power is continuously increasing in the Northern European grids. To assure safety in the operation of the power system, wind power plants are required to provide ancillary services, including reserve power attained through down-regulating the wind farm from its...... power plant. The developed procedure, the PossPOW algorithm, can also be used in the wind farm control as it yields a real-time wind farm power curve. The modern wind turbines have a possible power signal at the turbine level and the current state of the art is to aggregate those signals to achieve...... the wind farm scale production capacity. However the summation of these individual signals is simply an over-estimation for the wind power plant, due to reduced wake losses during curtailment. The determination of the possible power with the PossPOW algorithm works as follows: firstly the second...

Optimisation of VSC-HVDC Transmission for Wind Power Plants

DEFF Research Database (Denmark)

Silva, Rodrigo Da

Connection of Wind Power Plants (WPP), typically oshore, using VSCHVDC transmission is an emerging solution with many benefits compared to the traditional AC solution, especially concerning the impact on control architecture of the wind farms and the grid. The VSC-HVDC solution is likely to meet...... more stringent grid codes than a conventional AC transmission connection. The purpose of this project is to analyse how HVDC solution, considering the voltage-source converter based technology, for grid connection of large wind power plants can be designed and optimised. By optimisation, the project...... the robust control technique is applied is compared with the classical proportional-integral (PI) performance, by means of time domain simulation in a point-to-point HVDC connection. The three main parameters in the discussion are the wind power delivered from the offshore wind power plant, the variation...

Final Report on the Creation of the Wind Integration National Dataset (WIND) Toolkit and API: October 1, 2013 - September 30, 2015

Energy Technology Data Exchange (ETDEWEB)

Hodge, Bri-Mathias [National Renewable Energy Lab. (NREL), Golden, CO (United States)

2016-04-08

The primary objective of this work was to create a state-of-the-art national wind resource data set and to provide detailed wind plant output data for specific sites based on that data set. Corresponding retrospective wind forecasts were also included at all selected locations. The combined information from these activities was used to create the Wind Integration National Dataset (WIND), and an extraction tool was developed to allow web-based data access.

Wind-power plant

Energy Technology Data Exchange (ETDEWEB)

Kling, A

1976-08-26

The invention is concerned with a wind-power plant whose rotor axis is pivoted in the supporting structure and swingable around an axis of tilt, forming an angle with the rotor axis and the vertical axis, and allowing precession of the rotor. On changes of wind direction an electric positioning device is moving the rotor axis into the new direction in such a way that no precession forces are exerted on the supporting structure and this one may very easily be held. Instead of one rotor, also a type with two coaxial, co-planar countercurrent rotors may be used. Each of the two countercurrent rotors is carrying a number of magnetic poles, distributed all over the circumference, acting together with the magnetic poles of the other rotor. At least the poles of one rotor have electric line windings being connected by leads with a collector so that the two rotors form the two parts of a power generator being each rotatable with respect to the other ('stator' and 'rotor').

Using High-Fidelity Computational Fluid Dynamics to Help Design a Wind Turbine Wake

DEFF Research Database (Denmark)

Churchfield, Matthew J.; Wang, Qi; Scholbrock, A.

2016-01-01

Wind Farm Technology facility operated by Sandia National Laboratories in Lubbock, Texas. Prior simulation studies have shown that wake deflection may be used for wind-plant control that maximizes plant power output. In this study, simulations are performed to characterize wake deflection and general...

Power quality control of an autonomous wind-diesel power system based on hybrid intelligent controller.

Science.gov (United States)

Ko, Hee-Sang; Lee, Kwang Y; Kang, Min-Jae; Kim, Ho-Chan

2008-12-01

Wind power generation is gaining popularity as the power industry in the world is moving toward more liberalized trade of energy along with public concerns of more environmentally friendly mode of electricity generation. The weakness of wind power generation is its dependence on nature-the power output varies in quite a wide range due to the change of wind speed, which is difficult to model and predict. The excess fluctuation of power output and voltages can influence negatively the quality of electricity in the distribution system connected to the wind power generation plant. In this paper, the authors propose an intelligent adaptive system to control the output of a wind power generation plant to maintain the quality of electricity in the distribution system. The target wind generator is a cost-effective induction generator, while the plant is equipped with a small capacity energy storage based on conventional batteries, heater load for co-generation and braking, and a voltage smoothing device such as a static Var compensator (SVC). Fuzzy logic controller provides a flexible controller covering a wide range of energy/voltage compensation. A neural network inverse model is designed to provide compensating control amount for a system. The system can be optimized to cope with the fluctuating market-based electricity price conditions to lower the cost of electricity consumption or to maximize the power sales opportunities from the wind generation plant.

Offshore Wind Power Plant Technology Catalogue - Components of wind power plants, AC collection systems and HVDC systems

DEFF Research Database (Denmark)

Das, Kaushik; Antonios Cutululis, Nicolaos

2017-01-01

Traditionally, Offshore Wind Power Plants (OWPPs) are connected through many com-ponents as shown in the figure 1. An OWPP consists of controllable, variable speed Wind Turbines (WTs). These WTs are connected through Medium Voltage (MV) sub-marine cables typically at voltage level of upto 33-66 k...... for the cables as well reduce the power losses through them....

Short-Term Output Variations in Wind Farms--Implications for Ancillary Services in the United States: Preprint

Energy Technology Data Exchange (ETDEWEB)

Cadogan, J. [U.S. Department of Energy (US); Milligan, M. [National Renewable Energy Laboratory (US); Wan, Y. [National Renewable Energy Laboratory (US); Kirby, B. [Oak Ridge National Laboratory (US)

2001-09-21

With the advent of competition in the electric power marketplace, this paper reviews changes that affect wind and other renewable energy technologies, and discusses the role of federal and state policies in the recent wind installations in the United States. In particular, it reviews the implications of ancillary service requirements on a wind farm and presents initial operating results of monitoring one Midwest wind farm. Under federal energy policy, each generator must purchase, or otherwise provide for, ancillary services, such as dispatch, regulation, operation reserve, voltage regulation, and scheduling required to move power to load. As a renewable technology that depends on the forces of nature, short-term output variations are inherently greater for a wind farm than for a gas-fired combined cycle or a supercritical coal-fired unit.

Wind Plant Power Optimization and Control under Uncertainty

Science.gov (United States)

Jha, Pankaj; Ulker, Demet; Hutchings, Kyle; Oxley, Gregory

2017-11-01

The development of optimized cooperative wind plant control involves the coordinated operation of individual turbines co-located within a wind plant to improve the overall power production. This is typically achieved by manipulating the trajectory and intensity of wake interactions between nearby turbines, thereby reducing wake losses. However, there are various types of uncertainties involved, such as turbulent inflow and microscale and turbine model input parameters. In a recent NREL-Envision collaboration, a controller that performs wake steering was designed and implemented for the Longyuan Rudong offshore wind plant in Jiangsu, China. The Rudong site contains 25 Envision EN136-4 MW turbines, of which a subset was selected for the field test campaign consisting of the front two rows for the northeasterly wind direction. In the first row, a turbine was selected as the reference turbine, providing comparison power data, while another was selected as the controlled turbine. This controlled turbine wakes three different turbines in the second row depending on the wind direction. A yaw misalignment strategy was designed using Envision's GWCFD, a multi-fidelity plant-scale CFD tool based on SOWFA with a generalized actuator disc (GAD) turbine model, which, in turn, was used to tune NREL's FLORIS model used for wake steering and yaw control optimization. The presentation will account for some associated uncertainties, such as those in atmospheric turbulence and wake profile.

Vestas Power Plant Solutions Integrating Wind, Solar PV and Energy Storage

DEFF Research Database (Denmark)

Petersen, Lennart; Hesselbæk, Bo; Martinez, Antonio

2018-01-01

This paper addresses a value proposition and feasible system topologies for hybrid power plant solutions integrating wind, solar PV and energy storage and moreover provides insights into Vestas hybrid power plant projects. Seen from the perspective of a wind power plant developer, these hybrid...... solutions provide a number of benefits that could potentially reduce the Levelized Cost of Energy and enable entrance to new markets for wind power and facilitate the transition to a more sustainable energy mix. First, various system topologies are described in order to distinguish the generic concepts...... for the electrical infrastructure of hybrid power plants. Subsequently, the benefits of combining wind and solar PV power as well as the advantages of combining variable renewable energy sources with energy storage are elaborated. Finally, the world’s first utility-scale hybrid power plant combining wind, solar PV...

Modelling and Simulation of VSC-HVDC Connection for Wind Power Plants

DEFF Research Database (Denmark)

Chaudhary, Sanjay Kumar; Teodorescu, Remus; Rodriguez, Pedro

2009-01-01

This paper describes the modelling and simulation of offshore wind power plants (WPP) connected to the onshore power system grid by VSC based HVDC transmission. Offshore wind power plant is modelled with several wind turbine generators connected to two separate collector buses with their own plant...... wind turbines. Simulation of power ramping up and down as well as steady state operation has been demonstrated. As an additional case, the primary reserve control logic has been implemented and simulated in PSCAD model....

An Assessment of Wind Plant Complex Flows Using Advanced Doppler Radar Measurements

Science.gov (United States)

Gunter, W. S.; Schroeder, J.; Hirth, B.; Duncan, J.; Guynes, J.

2015-12-01

As installed wind energy capacity continues to steadily increase, the need for comprehensive measurements of wind plant complex flows to further reduce the cost of wind energy has been well advertised by the industry as a whole. Such measurements serve diverse perspectives including resource assessment, turbine inflow and power curve validation, wake and wind plant layout model verification, operations and maintenance, and the development of future advanced wind plant control schemes. While various measurement devices have been matured for wind energy applications (e.g. meteorological towers, LIDAR, SODAR), this presentation will focus on the use of advanced Doppler radar systems to observe the complex wind flows within and surrounding wind plants. Advanced Doppler radars can provide the combined advantage of a large analysis footprint (tens of square kilometers) with rapid data analysis updates (a few seconds to one minute) using both single- and dual-Doppler data collection methods. This presentation demonstrates the utility of measurements collected by the Texas Tech University Ka-band (TTUKa) radars to identify complex wind flows occurring within and nearby operational wind plants, and provide reliable forecasts of wind speeds and directions at given locations (i.e. turbine or instrumented tower sites) 45+ seconds in advance. Radar-derived wind maps reveal commonly observed features such as turbine wakes and turbine-to-turbine interaction, high momentum wind speed channels between turbine wakes, turbine array edge effects, transient boundary layer flow structures (such as wind streaks, frontal boundaries, etc.), and the impact of local terrain. Operational turbine or instrumented tower data are merged with the radar analysis to link the observed complex flow features to turbine and wind plant performance.

Wind Power Plant Prediction by Using Neural Networks: Preprint

Energy Technology Data Exchange (ETDEWEB)

Liu, Z.; Gao, W.; Wan, Y. H.; Muljadi, E.

2012-08-01

This paper introduces a method of short-term wind power prediction for a wind power plant by training neural networks based on historical data of wind speed and wind direction. The model proposed is shown to achieve a high accuracy with respect to the measured data.

Voltage Control in Wind Power Plants with Doubly Fed Generators

DEFF Research Database (Denmark)

Garcia, Jorge Martinez

In this work, the process of designing a wind power plant composed of; doubly fed induction generators, a static compensator unit, mechanically switched capacitors and on-load tap changer, for voltage control is shown. The selected control structure is based on a decentralized system, since...... supplied by the doubly fed induction generator wind turbines is overcome by installing a reactive power compensator, i.e. a static compensator unit, which is coordinated with the plant control by a specific dispatcher. This dispatcher is set according to the result of the wind power plant load flow....... To release the operation of the converters during steady-state disturbances, mechanically switched capacitors are installed in the wind power plant, which due to their characteristics, they are appropriate for permanent disturbances compensation. The mechanically switched capacitors are controlled to allow...

Wind Power Plant Voltage Control Optimization with Embedded Application of Wind Turbines and Statcom

DEFF Research Database (Denmark)

Wu, Qiuwei; Solanas, Jose Ignacio Busca; Zhao, Haoran

2017-01-01

Increasing wind power penetration and the size of wind power plants (WPPs) brings challenges to the operation and control of power systems. Most of WPPs are located far from load centers and the short circuit ratio at the point of common coupling (PCC) is low. The fluctuations of wind power...

Power Oscillation Damping from VSC-HVDC Connected Offshore Wind Power Plants

DEFF Research Database (Denmark)

Zeni, Lorenzo; Eriksson, Robert; Goumalatsos, Spyridon

2016-01-01

The implementation of power oscillation damping service on offshore wind power plants connected to onshore grids by voltage-source-converter-based high voltage direct current transmission is discussed. Novel design guidelines for damping controllers on voltage-source converters and wind power plant...... regarding real wind power plants are discussed: 1) robustness against control/communication delays; 2) limitations due to mechanical resonances in wind turbine generators; 3) actual capability of wind power plants to provide damping without curtailing production; and 4) power-ramp rate limiters....... controllers are derived, using phasor diagrams and a test network model and are then verified on a generic power system model. The effect of voltage regulators is analyzed, which is important for selecting the most robust damping strategy. Furthermore, other often disregarded practical implementation aspects...

IEA Wind Task 37 System Modeling Framework and Ontology for Wind Turbines and Plants

NARCIS (Netherlands)

Dykes, K; Sanchez Perez Moreno, S.; Zahle, Frederik; Ning, A; McWilliam, M.; Zaayer, M B

2017-01-01

This presentation will provide an overview of progress to date in the development of a system modeling framework and ontology for wind turbines and plants as part of the larger IEA Wind Task 37 on wind energy systems engineering. The goals of the effort are to create a set of guidelines for a common

Wind power plant for electricity generation

Energy Technology Data Exchange (ETDEWEB)

Landsiedel, E

1978-11-09

The invention concerns a wind power plant which rotates on a vertical axis and is suitable for the generation of electricity. This wind power machine with a vertical axis can be mounted at any height, so that it can catch the wind on the vertical axis of rotation. Further, it does not have to be turned into the direction of the wind and fixed. The purpose of the invention is to obtain equal load on the structure due to the vertical axis. The purpose of the invention is fulfilled by having the wind vanes fixed above one another from the bottom to the top in 6 different directions. The particular advantage of the invention lies in the fact that the auxiliary blades can bring the other blades to the operating position in good time, due to their particular method of fixing.

Low-power wind plants

International Nuclear Information System (INIS)

Kovalenko, V.I.; Shevchenko, Yu.V.; Shikhajlov, N.A.; Kokhanevich, V.P.; Tanan, G.L.

1993-01-01

Design peculiarities, as well as the prospects of development and introduction of the low-power (from 0.5 up to 4 kW) wind power plants (WPP) are considered. The variants of WPP with vertical and horizontal rotation axis are described. The data characterizing cost and structure of expenditures on WPP manufacture and operation are given

Wind farm balance of plant costs

International Nuclear Information System (INIS)

Craig, L.; Liebmann, C.

1992-01-01

The study consisted of a detailed investigation of the infrastructure required for the construction and operation of a windfarm in the UK. Costing of the equipment and installation was carried out for three UK sites, with different physical characteristics. A literature survey was carried out to determine current practice in the siting of turbines within windfarms in Europe and the USA. Wind turbines were then laid out on the sites selected for study. Requirements and costs for roads, foundations and site buildings, site electrical system and grid connection, the supervisory control and data acquisition system were discussed and evaluated. A comparison between the balance of plant costs for the 33-metre MS-3 400 kW wind turbine and the 50-metre LS-2 1 MW wind turbine was made for each area of study. Overall balance of plant costs was reviewed, with an investigation of the cost components which are most sensitive to variations. The balance of plant costs averaged over the three sites were 13.0 p/kWh/annum for the MS3 windfarms and 10.6 p/kWh/annum for the LS-2 windfarms. Maps of the sites under investigation, design drawings and tables of costs are included to give supporting information to the text. (author)

Operating of Small Wind Power Plants with Induction Generators

Directory of Open Access Journals (Sweden)

Jakub Nevrala

2008-01-01

Full Text Available This paper describes different systems of small wind power plants with induction generators used in the Czech Republic. Problems of wind power plants running with induction generators are solved within partial target of the research project MSM 6198910007. For small wind power plants is used induction motor as a generator. Parameters of the name plate of motor must be resolved for generator running on measuring base. These generators are running as a separately working generators or generators connected to the power grid. Methods of control these systems as a separately working, directly connecting to power grid, control by frequency converter and wiring by synchronous cascade are confronted on the measuring base too.

WEP. A wind energy planning system

International Nuclear Information System (INIS)

Larsen, H.V.

1991-11-01

The report describes the Wind Energy Planning system (WEP). It is intended as a decision support system to be used in the economic evaluation of wind energy projects. Such projects could be minor projects with only a single wind turbine or large wind farm projects consisting of several wind turbine plants. In the WEP system, a wind turbine is described by data on initial investment, possible later reinvestments, O and M costs, expected yearly production, life time, and capacity factor. The raising of loans are modelled, too. Depending on which output report is created, the value of the wind generated electricity is calculated in two different ways: either the electricity is assumed to be sold at a price (time series) given by the user, or the alternative conventional power production is modelled by its specific investment, O and M costs, life time, effectivity, fuel mix, and time series for fuel prices. Using these data, capacity credit and saved fuel and O and M costs are calculated. Due to the flexible data structure of the model, the user can easily create a scenario that models a large scale introduction of wind power. In such a scenario the gradual build up through several years of the wind power capacity can be modelled. The report describes in detail the menu structure, the input facilities, the output reports, and the organization of data. Also included is an example with full input documentation and output reports. (au)

Utilization and storage problems in wind power plants

Energy Technology Data Exchange (ETDEWEB)

Molly, J P

1977-01-01

The energy yield of a power plant consisting of wind energy converter and storer is considerably influenced by the choice of specific characteristic values of both components. Boundary conditions of the optimization process are site, consumer behavior and a minimum demand of supply safety. If the costs of the power plant components are known, then one may determine the cheapest wind power plant taking account of the boundary conditions. The preconditions and way of calculation for optimum rotary number, the best specific rotor disk power and the necessary storage capacity for a certain supply safety are given.

Land Use Requirements of Modern Wind Power Plants in the United States

Energy Technology Data Exchange (ETDEWEB)

Denholm, P.; Hand, M.; Jackson, M.; Ong, S.

2009-08-01

This report provides data and analysis of the land use associated with modern, large wind power plants (defined as greater than 20 megawatts (MW) and constructed after 2000). The analysis discusses standard land-use metrics as established in the life-cycle assessment literature, and then discusses their applicability to wind power plants. The report identifies two major 'classes' of wind plant land use: 1) direct impact (i.e., disturbed land due to physical infrastructure development), and 2) total area (i.e., land associated with the complete wind plant project). The analysis also provides data for each of these classes, derived from project applications, environmental impact statements, and other sources. It attempts to identify relationships among land use, wind plant configuration, and geography. The analysts evaluated 172 existing or proposed projects, which represents more than 26 GW of capacity. In addition to providing land-use data and summary statistics, they identify several limitations to the existing wind project area data sets, and suggest additional analysis that could aid in evaluating actual land use and impacts associated with deployment of wind energy.

Output power analyses for the thermodynamic cycles of thermal power plants

International Nuclear Information System (INIS)

Sun Chen; Cheng Xue-Tao; Liang Xin-Gang

2014-01-01

Thermal power plant is one of the important thermodynamic devices, which is very common in all kinds of power generation systems. In this paper, we use a new concept, entransy loss, as well as exergy destruction, to analyze the single reheating Rankine cycle unit and the single stage steam extraction regenerative Rankine cycle unit in power plants. This is the first time that the concept of entransy loss is applied to the analysis of the power plant Rankine cycles with reheating and steam extraction regeneration. In order to obtain the maximum output power, the operating conditions under variant vapor mass flow rates are optimized numerically, as well as the combustion temperatures and the off-design flow rates of the flue gas. The relationship between the output power and the exergy destruction rate and that between the output power and the entransy loss rate are discussed. It is found that both the minimum exergy destruction rate and the maximum entransy loss rate lead to the maximum output power when the combustion temperature and heat capacity flow rate of the flue gas are prescribed. Unlike the minimum exergy destruction rate, the maximum entransy loss rate is related to the maximum output power when the highest temperature and heat capacity flow rate of the flue gas are not prescribed. (general)

Modelling the economics of combined wind/hydro/diesel power systems

International Nuclear Information System (INIS)

Sinha, A.

1993-01-01

A model that stimulates the performance and economics of a combined wind/hydro/diesel plant with pumped storage has been developed. It is applied to a hypothetical site to demonstrate how a subset of the cheapest configuration of plant sizes may be identified, illustrating in particular the trade-off between the hydro storage capacity and the wind turbine penetration. It seems that, with the wind and water regimes employed, pumped storage is unlikely to have significant benefits, but may be beneficial in areas without natural inflow, in which case the reservoir is used as a store for excess wind output. (author)

Summary of wind data from nuclear power plant sites. [USA

Energy Technology Data Exchange (ETDEWEB)

Verholek, M. G.

1977-03-01

A summary of wind data from nuclear power plant sites is presented. National Weather Service archives are an immediately obvious source of wind data, but additional data sources are also available. Utility companies proposing to build nuclear power plants are required to establish on-site meteorological monitoring programs that include towers for collecting wind and temperature data for use in environmental impact assessments. These data are available for more than one hundred planned or operating nuclear power plant sites. A list of the sites, by state, is provided in Appendix A, while Appendix B contains an alphabetical list of the sites. This site wind data provides a valuable addition to the existing NWS data sets, and significantly enlarges the multilevel data presently available. The wind data published through the NRC is assembled and assessed here in order to provide a supplement to existing data sets.

Damping of Low Frequency Power System Oscillations with Wind Power Plants

DEFF Research Database (Denmark)

Adamczyk, Andrzej Grzegorz

of wind power plants on power system low frequency oscillations and identify methods and limitations for potential contribution to the damping of such oscillations. Consequently, the first part of the studies focuses on how the increased penetration of wind power into power systems affects their natural...... oscillatory performance. To do so, at first a generic test grid displaying a complex inter-area oscillation pattern is introduced. After the evaluation of the test grid oscillatory profile for various wind power penetration scenarios, it is concluded that full-converter based wind power plant dynamics do......-synchronous power source. The main body of the work is devoted to the damping control design for wind power plants with focus on the impact of such control on the plant operation. It can be expected that the referred impact is directly proportional to the control effort, which for power processing devices should...

Modeling of the wind power plant using software DIgSILENT Power factory

International Nuclear Information System (INIS)

Mladenovski, Ljubisha; Iliev, Atanas; Fushtikj, Vangel

2004-01-01

This paper presents a method for creating a model of the wind power plant NORDEX N-60 in the DIgSILENT Power factory software. At the beginning, the characteristics of the wind power plant and the used software are shortly described. The next step is modeling the part of the power system where the wind power plant will be connected to the grid The modeling of the turbine part and the generator part of the wind power plant is made with blocks, which are part of the machine block of the composite model. Finally, the results obtained from performed practically oriented simulations are presented in graphical form. Design of the model of the wind power plant NORDEX N-60 was performed at the Faculty of Electrical Engineering, at the University of Rostock, Germany, as a part of the DYSIMAC project. (Author)

Energy output estimation for a small wind turbine positioned on a rooftop in the urban environment with and without a duct

Energy Technology Data Exchange (ETDEWEB)

Beller, C.

2011-05-15

Nowadays, wind turbines in general, but also urban wind turbines attained acceptance to a certain extend. Conceptual designs and some examples in reality exist, where small-scale wind turbines have been implemented close to buildings or even integrated in the building structure. This work is aiming to estimate how much energy a wind turbine could produce in the built environment, depending on its integration and configuration. On the basis of measurements taken on the rooftop of H.C. Orsted Institut in Copenhagen, which is located in an urban area, a comparison of fictive free standing turbines with ducted turbines of the same type was carried out. First, a prevailing wind energy direction was detected with rough mean velocity and frequency calculations. Next, a duct was aligned with the direction, where the highest energy potential was found. Further calculations were conducted with more detailed wind velocity distributions, depending on the wind direction sectors. The duct's wind velocity amplification capability was set to 14%, while a total opening angle of 30. was assumed to be accessible from both sides. With the simplifying assumptions and the uncertainties at the location of measurement, the free standing turbines had an energy potential of 300kWh/m2/a for the horizontal axis wind turbine (HAWT) and for the vertical axis wind turbine (VAWT) 180kWh/m2/a. For the ducted turbines an energy output of 180kWh/m2/a was found for the HAWT configuration, while the VAWT configuration reached an output of 110kWh/m2/a. The available wind had an energy potential of 730kWh/m2/a. Evaluating these results it seems a free standing turbine is preferable, when only considering the power output, whereas the ducted version comprises properties, which are important considering the requirements needed in the inhabited area such as safety and noise issues. (Author)

Guideline for the erection of wind power plants

International Nuclear Information System (INIS)

Behnke, R.; Kampet, T.

1990-01-01

This guideline for the erection of a proper wind power plant is to give hints on some important stations on the way from the idea up to perfect operation of the plant. This guideline, however, does not substitute the professional knowledge of a consulting company or firm neutral to manufacturing. Such firms are listed in an attached list of addresses at the end. When establishing this guideline possible problems which occur in the utilization of wind energy have been considered. These items which in some cases seem to be very problematic should not prevent anybody to trust in the application of wind energy wherever it is economically justified or ecologically useful. (orig./BWI) [de

Coordinated voltage control for multiple wind plants in Eastern Wyoming. Analysis, field experience and validation

Energy Technology Data Exchange (ETDEWEB)

Miller, Nicholas; MacDowell, Jason; Chmiel, Gary; Konopinski, Ryan; Gautam, Durga [GE Energy, Schenectady, NY (United States); Laughter, Grant; Hagen, Dave [PacifiCorp., Salt Lake City, UT (United States)

2012-07-01

At high levels of wind power penetration, multiple wind plants may be the predominant generation resource over large geographic areas. Thus, not only do wind plants need to provide a high level of functionality, they must coordinate properly with each other. This paper describes the analysis and field testing of wind plant voltage controllers designed to improve system voltage performance through passive coordination. The described wind power plant controls can coordinate the real and reactive power response of multiple wind turbines and thereby make the plant function as a single ''grid friendly'' power generation source. For this application, involving seven large wind plants with predominantly GE wind turbines in Eastern Wyoming, the voltage portion of the controllers were configured and tuned to allow the collective reactive power response of multiple wind plants in the region to work well together. This paper presents the results of the initial configuration and tuning study, and the results of the subsequent field tuning and testing of the modified controls. The paper also presents some comparisons of the measured field performance with the stability simulation models, which show that the available wind plant models provide accurate, high fidelity results for actual operating conditions of commercial wind power plants. (orig.)

Wind Plant Preconstruction Energy Estimates. Current Practice and Opportunities

Energy Technology Data Exchange (ETDEWEB)

Clifton, Andrew [National Renewable Energy Lab. (NREL), Golden, CO (United States); Smith, Aaron [National Renewable Energy Lab. (NREL), Golden, CO (United States); Fields, Michael [National Renewable Energy Lab. (NREL), Golden, CO (United States)

2016-04-19

Understanding the amount of energy that will be harvested by a wind power plant each year and the variability of that energy is essential to assessing and potentially improving the financial viability of that power plant. The preconstruction energy estimate process predicts the amount of energy--with uncertainty estimates--that a wind power plant will deliver to the point of revenue. This report describes the preconstruction energy estimate process from a technical perspective and seeks to provide insight into the financial implications associated with each step.

Voltage Feedback based Harmonic Compensation for an Offshore Wind Power Plant

DEFF Research Database (Denmark)

Chaudhary, Sanjay K.; Lascu, Cristian; Teodorescu, Remus

2016-01-01

When an offshore wind power plant is connected to the grid, there is a risk of amplification of certain harmonics and appearance resonances at the point of connection due to the interaction between the grid network and the wind power plant network. Hence, the plant developer is obliged to maintain...

A Comparative Study of CFD Models of a Real Wind Turbine in Solar Chimney Power Plants

Directory of Open Access Journals (Sweden)

Ehsan Gholamalizadeh

2017-10-01

Full Text Available A solar chimney power plant consists of four main parts, a solar collector, a chimney, an energy storage layer, and a wind turbine. So far, several investigations on the performance of the solar chimney power plant have been conducted. Among them, different approaches have been applied to model the turbine inside the system. In particular, a real wind turbine coupled to the system was simulated using computational fluid dynamics (CFD in three investigations. Gholamalizadeh et al. simulated a wind turbine with the same blade profile as the Manzanares SCPP’s turbine (FX W-151-A blade profile, while a CLARK Y blade profile was modelled by Guo et al. and Ming et al. In this study, simulations of the Manzanares prototype were carried out using the CFD model developed by Gholamalizadeh et al. Then, results obtained by modelling different turbine blade profiles at different turbine rotational speeds were compared. The results showed that a turbine with the CLARK Y blade profile significantly overestimates the value of the pressure drop across the Manzanares prototype turbine as compared to the FX W-151-A blade profile. In addition, modelling of both blade profiles led to very similar trends in changes in turbine efficiency and power output with respect to rotational speed.

Options to Improve the Quality of Wind Generation Output Forecasting with the Use of Available Information as Explanatory Variables

Directory of Open Access Journals (Sweden)

Rafał Magulski

2015-06-01

Full Text Available Development of wind generation, besides its positive aspects related to the use of renewable energy, is a challenge from the point of view of power systems’ operational security and economy. The uncertain and variable nature of wind generation sources entails the need for the for the TSO to provide adequate reserves of power, necessary to maintain the grid’s stable operation, and the actors involved in the trading of energy from these sources incur additional of balancing unplanned output deviations. The paper presents the results of analyses concerning the options to forecast a selected wind farm’s output exercised by means of different methods of prediction, using a different range of measurement and forecasting data available on the farm and its surroundings. The analyses focused on the evaluation of forecast errors, and selection of input data for forecasting models and assessment of their impact on prediction quality improvement.

Real-Time Wavelet-Based Coordinated Control of Hybrid Energy Storage Systems for Denoising and Flattening Wind Power Output

Directory of Open Access Journals (Sweden)

Tran Thai Trung

2014-10-01

Full Text Available Since the penetration level of wind energy is continuously increasing, the negative impact caused by the fluctuation of wind power output needs to be carefully managed. This paper proposes a novel real-time coordinated control algorithm based on a wavelet transform to mitigate both short-term and long-term fluctuations by using a hybrid energy storage system (HESS. The short-term fluctuation is eliminated by using an electric double-layer capacitor (EDLC, while the wind-HESS system output is kept constant during each 10-min period by a Ni-MH battery (NB. State-of-charge (SOC control strategies for both EDLC and NB are proposed to maintain the SOC level of storage within safe operating limits. A ramp rate limitation (RRL requirement is also considered in the proposed algorithm. The effectiveness of the proposed algorithm has been tested by using real time simulation. The simulation model of the wind-HESS system is developed in the real-time digital simulator (RTDS/RSCAD environment. The proposed algorithm is also implemented as a user defined model of the RSCAD. The simulation results demonstrate that the HESS with the proposed control algorithm can indeed assist in dealing with the variation of wind power generation. Moreover, the proposed method shows better performance in smoothing out the fluctuation and managing the SOC of battery and EDLC than the simple moving average (SMA based method.

Symmetrical and Unsymmetrical Fault Currents of a Wind Power Plant: Preprint

Energy Technology Data Exchange (ETDEWEB)

Gevorgian, V.; Singh, M.; Muljadi, E.

2011-12-01

This paper investigates the short-circuit behavior of a wind power plant for different types of wind turbines. Both symmetrical faults and unsymmetrical faults are investigated. The size of wind power plants (WPPs) keeps getting bigger and bigger. The number of wind plants in the U.S. has increased very rapidly in the past 10 years. It is projected that in the U.S., the total wind power generation will reach 330 GW by 2030. As the importance of WPPs increases, planning engi-neers must perform impact studies used to evaluate short-circuit current (SCC) contribution of the plant into the transmission network under different fault conditions. This information is needed to size the circuit breakers, to establish the proper sys-tem protection, and to choose the transient suppressor in the circuits within the WPP. This task can be challenging to protec-tion engineers due to the topology differences between different types of wind turbine generators (WTGs) and the conventional generating units. This paper investigates the short-circuit behavior of a WPP for different types of wind turbines. Both symmetrical faults and unsymmetrical faults are investigated. Three different soft-ware packages are utilized to develop this paper. Time domain simulations and steady-state calculations are used to perform the analysis.

Solar wind power electric plant on Vis (Croatia)

International Nuclear Information System (INIS)

1998-01-01

A project of a solar photovoltaic electric power plant presented by the Republic of Croatia at the meeting of the E.P.I.A. Mission for photovoltaic technology of the Mediterranean countries, aroused a great interest of the representatives of the invited countries. However, the interest within Croatia in the project has disappeared although E.P.I.A. offered a financing of two thirds of costs. There are attempts to construct 1800 kw wind-driven generators at the same location not taking into consideration a possibility of building a hybrid solar-wind-power electric plant. The chance that the solar part is completely of domestic origin is not accepted but the preference is given to the building of imported wind-driven generators. (orig.)

Repowering of wind farms - A case study

Energy Technology Data Exchange (ETDEWEB)

Nivedh, B.S. [Quality Engineering and Software Technologies, Bangalore (India); Devi, R.P.K. [College of Engineering. Power Systems Engineering, Guindy (India); Sreevalsan, E. [Gamesa Wind Turbines India Private Limited, Chennai (India)

2012-07-01

The main objective of the study is to devise a method for assessing the repowering potential and to improve the energy output from the wind farms and also to understand the impact on the power quality due to repowering. With repowering, the first-generation wind turbines can be replaced with modern multi-megawatt wind turbines. To carry-out the study an old wind farm located at Kayathar, Tamilnadu is selected. The wind farm was commissioned in 1990's with a capacity of 7.35MW, which consists of 36 Wind Turbines each with the capacity of 200kW and 225kW. The present annual energy generation of the wind farm is 7350MWhr with the plant load factor of 11.41%. The intent of this study is to predict the annual energy output of the wind farm after the repowering using WAsP (Wind Atlas Analysis Application Program). Further this study analyses the power quality issues of the various Wind Turbines. In addition, the main feeder, in which the wind farm which is taken for the study also modeled and the impact on power quality due to repowering also studied. Simulations were carried out using MATLAB. The results are analyzed to understand the significance of repowering to overcome the energy crisis of the nation since the best locations for wind in India are occupied by old wind turbines. The following are the observations and conclusions from the above study. Plant load factor (PLF) increased to 24 %, Energy yield increased to more than 4 times and the capacity of the wind farm became double. And in the view of power quality, comparing to the existing Feeder, Repowered Feeder having less reactive power consumption, voltage variations and flickers except the harmonic distortion. (Author)

First Aspect of Conventional Power System Assessment for High Wind Power Plants Penetration

Directory of Open Access Journals (Sweden)

A Merzic

2012-11-01

Full Text Available Most power systems in underdeveloped and developing countries are based on conventional power plants, mainly "slow-response" thermal power plants and a certain number of hydro power plants; characterized by inflexible generating portfolios and traditionally designed to meet own electricity needs. Taking into account operational capabilities of conventional power systems, their development planning will face problems with integration of notable amounts of installed capacities in wind power plants (WPP. This is what highlights the purpose of this work and in that sense, here, possible variations of simulated output power from WPP in the 10 minute and hourly time interval, which need to be balanced, are investigated, presented and discussed. Comparative calculations for the amount of installed power in WPP that can be integrated into a certain power system, according to available secondary balancing power amounts, in case of concentrated and dispersed future WPP are given. The stated has been done using a part of the power system of Bosnia and Herzegovina. In the considered example, by planned geographically distributed WPP construction, even up to cca. 74% more in installed power of WPP can be integrated into the power system than in case of geographically concentrated WPP construction, for the same available amount of (secondary balancing power. These calculations have shown a significant benefit of planned, geographically distributed WPP construction, as an important recommendation for the development planning of conventional power systems, with limited balancing options. Keywords: balancing reserves,  geographical dispersion, output power  variations

Efficient Approach for Harmonic Resonance Identification of Large Wind Power Plants

DEFF Research Database (Denmark)

Ebrahimzadeh, Esmaeil; Blaabjerg, Frede; Wang, Xiongfei

2016-01-01

Unlike conventional power systems where the resonance frequencies are mainly determined by the passive components parameters, large Wind Power Plants (WPPs) may introduce additional harmonic resonances because of the interactions of the wideband control systems of power converters with each other...... and with passive components. This paper presents an efficient approach for identification of harmonic resonances in large WPPs containing power electronic converters, cable, transformer, capacitor banks, shunt reactors, etc. The proposed approach introduces a large WPP as a Multi-Input Multi-Output (MIMO) control...... system by considering the linearized models of the inner control loops of grid-side converters. Therefore, the resonance frequencies of the WPP resulting from passive components and the control loop interactions are identified based on the determinant of the transfer function matrix of the introduced...

Two-Stage Robust Security-Constrained Unit Commitment with Optimizable Interval of Uncertain Wind Power Output

Directory of Open Access Journals (Sweden)

Dayan Sun

2017-01-01

Full Text Available Because wind power spillage is barely considered, the existing robust unit commitment cannot accurately analyze the impacts of wind power accommodation on on/off schedules and spinning reserve requirements of conventional generators and cannot consider the network security limits. In this regard, a novel double-level robust security-constrained unit commitment formulation with optimizable interval of uncertain wind power output is firstly proposed in this paper to obtain allowable interval solutions for wind power generation and provide the optimal schedules for conventional generators to cope with the uncertainty in wind power generation. The proposed double-level model is difficult to be solved because of the invalid dual transform in solution process caused by the coupling relation between the discrete and continuous variables. Therefore, a two-stage iterative solution method based on Benders Decomposition is also presented. The proposed double-level model is transformed into a single-level and two-stage robust interval unit commitment model by eliminating the coupling relation, and then this two-stage model can be solved by Benders Decomposition iteratively. Simulation studies on a modified IEEE 26-generator reliability test system connected to a wind farm are conducted to verify the effectiveness and advantages of the proposed model and solution method.

Multiple regression approach to predict turbine-generator output for Chinshan nuclear power plant

International Nuclear Information System (INIS)

Chan, Yea-Kuang; Tsai, Yu-Ching

2017-01-01

The objective of this study is to develop a turbine cycle model using the multiple regression approach to estimate the turbine-generator output for the Chinshan Nuclear Power Plant (NPP). The plant operating data was verified using a linear regression model with a corresponding 95% confidence interval for the operating data. In this study, the key parameters were selected as inputs for the multiple regression based turbine cycle model. The proposed model was used to estimate the turbine-generator output. The effectiveness of the proposed turbine cycle model was demonstrated by using plant operating data obtained from the Chinshan NPP Unit 2. The results show that this multiple regression based turbine cycle model can be used to accurately estimate the turbine-generator output. In addition, this study also provides an alternative approach with simple and easy features to evaluate the thermal performance for nuclear power plants.

Multiple regression approach to predict turbine-generator output for Chinshan nuclear power plant

Energy Technology Data Exchange (ETDEWEB)

Chan, Yea-Kuang; Tsai, Yu-Ching [Institute of Nuclear Energy Research, Taoyuan City, Taiwan (China). Nuclear Engineering Division

2017-03-15

The objective of this study is to develop a turbine cycle model using the multiple regression approach to estimate the turbine-generator output for the Chinshan Nuclear Power Plant (NPP). The plant operating data was verified using a linear regression model with a corresponding 95% confidence interval for the operating data. In this study, the key parameters were selected as inputs for the multiple regression based turbine cycle model. The proposed model was used to estimate the turbine-generator output. The effectiveness of the proposed turbine cycle model was demonstrated by using plant operating data obtained from the Chinshan NPP Unit 2. The results show that this multiple regression based turbine cycle model can be used to accurately estimate the turbine-generator output. In addition, this study also provides an alternative approach with simple and easy features to evaluate the thermal performance for nuclear power plants.

Hybrid biomass-wind power plant for reliable energy generation

International Nuclear Information System (INIS)

Perez-Navarro, A.; Alfonso, D.; Alvarez, C.; Ibanez, F.; Sanchez, C.; Segura, I.

2010-01-01

Massive implementation of renewable energy resources is a key element to reduce CO 2 emissions associated to electricity generation. Wind resources can provide an important alternative to conventional electricity generation mainly based on fossil fuels. However, wind generators are greatly affected by the restrictive operating rules of electricity markets because, as wind is naturally variable, wind generators may have serious difficulties on submitting accurate generation schedules on a day ahead basis, and on complying with scheduled obligations in real-time operation. In this paper, an innovative system combining a biomass gasification power plant, a gas storage system and stand-by generators to stabilize a generic 40 MW wind park is proposed and evaluated with real data. The wind park power production model is based on real data about power production of a Spanish wind park and a probabilistic approach to quantify fluctuations and so, power compensation needs. The hybrid wind-biomass system is analysed to obtain main hybrid system design parameters. This hybrid system can mitigate wind prediction errors and so provide a predictable source of electricity. An entire year cycle of hourly power compensations needs has been simulated deducing storage capacity, extra power needs of the biomass power plant and stand-by generation capacity to assure power compensation during critical peak hours with acceptable reliability. (author)

Smooth feeding-in of wind energy via hydrogen

International Nuclear Information System (INIS)

Lehmann, J.; Sponholz, C.; Luschtinetz, O.U.T.; Miege, A.; Sandlass, H.

2006-01-01

For the northern part of Germany the harvest of wind energy became characteristic. 1,018 GW have been installed by 2004. A higher electricity production with re-powered wind parks on shore and new off shore parks is planned. The estimated production could reach 50 GW by 2020. On the other hand, more than 20 30 % discontinuous electricity related to the demand could bring instabilities of the net. Unfortunately the demand in North-Germany is a relatively small one and the net is weak. There are three possibilities to protect the net: 1. Reconstruction of the net, especially net extension 2. Improvement of the prognosis of wind and electricity consumption as well 3. A net management, which shuts up wind parks during less demand periods Point 2 and 3 are related with the stand by of back-up power, power delivered by conventional power stations or storage power stations (for example storage by water pumping). The proposal is as follows: Wind parks should be connected with a loop from electrolysis, gas storage and reconversion of hydrogen into electricity. In this way a park will be able to feed electricity into the net according to the actual demand and controlled by the demand. Going into detail a wind farm can run according to four scenarios. The first one is the conventional wind park, which causes the problems mentioned above. The electrical energy output follows the natural wind yield and the grid has to be adapted to the wind power feed-in. One solution for a temporal decoupling of wind yield and electricity output is a combination of windmills with a storage loop as shown in scenario II and IV. The system of scenario II de-couples the fluctuating input (wind) and the constant output (electricity). The advantage of this system is that the electrical output is constant and independent of the actual wind speed. For this reason this wind park acts as a constant power plant within the grid. Scenario Ill, the grid adapted feed-in, extends the former scenario with a

Probabilistic Harmonic Modeling of Wind Power Plants

DEFF Research Database (Denmark)

Guest, Emerson; Jensen, Kim H.; Rasmussen, Tonny Wederberg

2017-01-01

A probabilistic sequence domain (SD) harmonic model of a grid-connected voltage-source converter is used to estimate harmonic emissions in a wind power plant (WPP) comprised of Type-IV wind turbines. The SD representation naturally partitioned converter generated voltage harmonics into those...... with deterministic phase and those with probabilistic phase. A case study performed on a string of ten 3MW, Type-IV wind turbines implemented in PSCAD was used to verify the probabilistic SD harmonic model. The probabilistic SD harmonic model can be employed in the planning phase of WPP projects to assess harmonic...

POSSPOW: Possible Power of Offshore Wind Power Plants

DEFF Research Database (Denmark)

Giebel, Gregor; Göçmen, Tuhfe; Sørensen, Poul Ejnar

2013-01-01

Introduction In recent years, the very large offshore wind farms were designed as wind power plants, including possibilities to contribute to the stability of the grid by offering grid services (also called ancillary services). One of those services is reserve power, which is achieved by down......-regulating the wind farm from its maximum possible power. The power can be ramped up quite quickly, but the influence of wakes makes it difficult to assess the exact amount of down-regulation available to sell. Currently, Transmission System Operators (TSOs) have no real way to determine exactly the possible power...... will be verified on some of the large offshore wind farms owned by Vattenfall, and possibly in a DONG Energy wind farm too. Dedicated experiments to the wind flow in large offshore wind farms are planned. Main body of abstract Modern wind turbines have a SCADA signal called possible power. In normal operation...

Forecasting winds over nuclear power plants statistics

International Nuclear Information System (INIS)

Marais, Ch.

1997-01-01

In the event of an accident at nuclear power plant, it is essential to forecast the wind velocity at the level where the efflux occurs (about 100 m). At present meteorologists refine the wind forecast from the coarse grid of numerical weather prediction (NWP) models. The purpose of this study is to improve the forecasts by developing a statistical adaptation method which corrects the NWP forecasts by using statistical comparisons between wind forecasts and observations. The Multiple Linear Regression method is used here to forecast the 100 m wind at 12 and 24 hours range for three Electricite de France (EDF) sites. It turns out that this approach gives better forecasts than the NWP model alone and is worthy of operational use. (author)

Quantifying the Benefits of Combining Offshore Wind and Wave Energy

Science.gov (United States)

Stoutenburg, E.; Jacobson, M. Z.

2009-12-01

For many locations the offshore wind resource and the wave energy resource are collocated, which suggests a natural synergy if both technologies are combined into one offshore marine renewable energy plant. Initial meteorological assessments of the western coast of the United States suggest only a weak correlation in power levels of wind and wave energy at any given hour associated with the large ocean basin wave dynamics and storm systems of the North Pacific. This finding indicates that combining the two power sources could reduce the variability in electric power output from a combined wind and wave offshore plant. A combined plant is modeled with offshore wind turbines and Pelamis wave energy converters with wind and wave data from meteorological buoys operated by the US National Buoy Data Center off the coast of California, Oregon, and Washington. This study will present results of quantifying the benefits of combining wind and wave energy for the electrical power system to facilitate increased renewable energy penetration to support reductions in greenhouse gas emissions, and air and water pollution associated with conventional fossil fuel power plants.

Dependability of wind energy generators with short-term energy storage.

Science.gov (United States)

Sørensen, B

1976-11-26

Power fluctuations and power duration curves for wind energy generators, including energy storage facilities of a certain capacity, are compared to those of typical nuclear reactors. A storage system capable of delivering the yearly average power output for about 10 hours already makes the dependability of the wind energy system comparable to that of a typical nuclear plant.

Overplanting in offshore wind power plants in different regulatory regimes

DEFF Research Database (Denmark)

Wolter, Christoph; Klinge Jacobsen, Henrik; Rogdakis, Georgios

2016-01-01

framework results more favourable to overplanting. The results indicate that current conceivable offshore wind power plants in the UK can increase their economic value by around 30 mio AC when optimising their capacity setup. In Denmark, current regulations are not suitable for overplanting causing loss...... of value when optimising the capacity design of wind power plants.......Offshore wind power’s journey towards being competitive with other generation technologies relies on technical innovation and maturation, but also on further optimisation of proven and mature solutions. Capacity optimisation or so-called overplanting is one example of optimisation, which...

Grid Integration Issues for Large Scale Wind Power Plants (WPPs)

DEFF Research Database (Denmark)

Wu, Qiuwei; Xu, Zhao; Østergaard, Jacob

2010-01-01

transmission system operators (TSOs) over the world have come up the grid codes to request the wind power plants (WPPs) to have more or less the same operating capability as the conventional power plants. The grid codes requirements from other TSOs are under development. This paper covers the steady state......The penetration level of wind power into the power system over the world have been increasing very fast in the last few years and is still keeping the fast growth rate. It is just a matter of time that the wind power will be comparable to the conventional power generation. Therefore, many...

Using H∞ to design robust POD controllers for wind power plants

DEFF Research Database (Denmark)

Mehmedalic, Jasmin; Knüppel, Thyge; Østergaard, Jacob

2012-01-01

Large wind power plants (WPPs) can help to improve small signal stability by increasing the damping of electromechanical modes of oscillation. This can be done by adding a power system oscillation damping (POD) controller to the wind power plants, similar to power system stabilizer (PSS......) controllers on conventional generation. Here two different design methods are evaluated for their suitability in producing a robust power system oscillation damping controller for wind power plants with full-load converter wind turbine generators (WTGs). Controllers are designed using classic PSS design and H......∞ methods and the designed controllers evaluated on both performance and robustness. It is found that the choice of control signal has a large influence on the robustness of the controllers, and the best performance and robustness is found when the converter active power command is used as control signal...

Multi-objective stochastic scheduling optimization model for connecting a virtual power plant to wind-photovoltaic-electric vehicles considering uncertainties and demand response

International Nuclear Information System (INIS)

Ju, Liwei; Li, Huanhuan; Zhao, Junwei; Chen, Kangting; Tan, Qingkun; Tan, Zhongfu

2016-01-01

Highlights: • Our research focuses on virtual power plant. • Electric vehicle group and demand response are integrated into virtual power plant. • Stochastic chance constraint planning is applied to overcome uncertainties. • A multi-objective stochastic scheduling model is proposed for virtual power plant. • A three-stage hybrid intelligent solution algorithm is proposed for solving the model. - Abstract: A stochastic chance-constrained planning method is applied to build a multi-objective optimization model for virtual power plant scheduling. Firstly, the implementation cost of demand response is calculated using the system income difference. Secondly, a wind power plant, photovoltaic power, an electric vehicle group and a conventional power plant are aggregated into a virtual power plant. A stochastic scheduling model is proposed for the virtual power plant, considering uncertainties under three objective functions. Thirdly, a three-stage hybrid intelligent solution algorithm is proposed, featuring the particle swarm optimization algorithm, the entropy weight method and the fuzzy satisfaction theory. Finally, the Yunnan distributed power demonstration project in China is utilized for example analysis. Simulation results demonstrate that when considering uncertainties, the system will reduce the grid connection of the wind power plant and photovoltaic power to decrease the power shortage punishment cost. The average reduction of the system power shortage punishment cost and the operation revenue of virtual power plant are 61.5% and 1.76%, respectively, while the average increase of the system abandoned energy cost is 40.4%. The output of the virtual power plant exhibits a reverse distribution with the confidence degree of the uncertainty variable. The proposed algorithm rapidly calculates a global optimal set. The electric vehicle group could provide spinning reserve to ensure stability of the output of the virtual power plant. Demand response could

Provision of enhanced ancillary services from wind power plants - Examples and challenges

DEFF Research Database (Denmark)

Hansen, Anca Daniela; Altin, Müfit; Iov, Florin

2016-01-01

Emphasis in this article is on the power system impact of wind power plants capability to provide enhanced ancillary services, i.e. temporary frequency response (TFR) and power oscillation damping (POD). The main objective of the article is to analyze and justify the challenges in the use of TFR...... and POD from wind power plants (WPPs). The study is conducted with an aggregated wind power plant model which is integrated into a generic power system model, specifically designed to assess the targeted ancillary services in a relatively simple, but still relevant environment. Various case studies...... with different wind power penetration levels are considered. The study shows that WPPs can provide additional control features such as TFR and POD to enhance the stability of power systems with large share of wind power. Nevertheless, the results illustrate that the power system stability can be potentially...

Variable Frequency Operations of an Offshore Wind Power Plant with HVDC-VSC: Preprint

Energy Technology Data Exchange (ETDEWEB)

Gevorgian, V.; Singh, M.; Muljadi, E.

2011-12-01

In this paper, a constant Volt/Hz operation applied to the Type 1 wind turbine generator. Various control aspects of Type 1 generators at the plant level and at the turbine level will be investigated. Based on DOE study, wind power generation may reach 330 GW by 2030 at the level of penetration of 20% of the total energy production. From this amount of wind power, 54 GW of wind power will be generated at offshore wind power plants. The deployment of offshore wind power plants requires power transmission from the plant to the load center inland. Since this power transmission requires submarine cable, there is a need to use High-Voltage Direct Current (HVDC) transmission. Otherwise, if the power is transmitted via alternating current, the reactive power generated by the cable capacitance may cause an excessive over voltage in the middle of the transmission distance which requires unnecessary oversized cable voltage breakdown capability. The use of HVDC is usually required for transmission distance longer than 50 kilometers of submarine cables to be economical. The use of HVDC brings another advantage; it is capable of operating at variable frequency. The inland substation will be operated to 60 Hz synched with the grid, the offshore substation can be operated at variable frequency, thus allowing the wind power plant to be operated at constant Volt/Hz. In this paper, a constant Volt/Hz operation applied to the Type 1 wind turbine generator. Various control aspects of Type 1 generators at the plant level and at the turbine level will be investigated.

Wind power plants the fuel savers

International Nuclear Information System (INIS)

Akbar, M.

2006-01-01

Wind is a converted from of solar energy. The Sun's radiation heats different parts of the earth at variable rates as the earth surfaces absorb or reflect at different rates. This in turn causes portions of the atmosphere to warm at varying levels. The hot air rises reducing atmospheric pressure at the earth's surface beneath, the cooler air rushes to replace it and in the process creates a momentum called wind. Air possesses mass and when it sets into motion, it contains the energy of that motion, called the Kinetic Energy. A part of the Kinetic Energy of the wind can be converted into other forms of energy i.e. mechanical force or electric power that can be used to perform work. The cost of electric energy from the wind system has dropped from the initial cost of 30 to 40 Cents per kWh to about 5 to 7 Cents/k Wh during the past 20 years. The costs are continually declining as the technology is advanced, the unit size is increased and larger plants are built. Wind power is now a viable, robust and fast growing industry. The cost of wind energy is expected to drop to 2 to 3 Cents / kWh during the next 5 to 10 years. Due to sky-rocketing prices of the fossil fuels, the competitive position of power generation technologies is rapidly changing. Wind energy is likely to emerge as the cheapest source of electric power generation in the global market in the near future. The current assessment of the global wind resources indicate that the wind energy potential is more than double the world's electricity needs. (author)

Application of Spatial Models in Making Location Decisions of Wind Power Plant in Poland

Science.gov (United States)

Płuciennik, Monika; Hełdak, Maria; Szczepański, Jakub; Patrzałek, Ciechosław

2017-10-01

In this paper,we explore the process of making decisions on the location of wind power plants in Poland in connection with a gradually increasing consumption of energy from renewable sources and the increase of impact problems of such facilities. The location of new wind power plants attracts much attention, and both positive and negative publicity. Visualisations can be of assistance when choosing the most advantageous location for a plant, as three-dimensional variants of the facility to be constructed can be prepared. This work involves terrestrial laser scanning of an existing wind power plant and 3D modelling followed by. The model could be subsequently used in visualisation of real terrain, with special purpose in local land development plan. This paper shows a spatial model of a wind power plant as a new element of a capital investment process in Poland. Next, we incorporate the model into an undeveloped site, intended for building a wind farm, subject to the requirements for location of power plants.

A Chronological Reliability Model to Assess Operating Reserve Allocation to Wind Power Plants: Preprint

International Nuclear Information System (INIS)

Milligan, M. R.

2001-01-01

As the use of wind power plants increases worldwide, it is important to understand the effect these power sources have on the operations of the grid. This paper focuses on the operating reserve impact of wind power plants. Many probabilistic methods have been applied to power system analysis, and some of these are the basis of reliability analysis. This paper builds on a probabilistic technique to allocate the operating reserve burden among power plants in the grid. The method was originally posed by Strbac and Kirschen[1] and uses an allocation that prorates the reserve burden based on expected energy not delivered. Extending this method to include wind power plants allows the reserve burden to be allocated among different plants using the same method, yet incorporates information about the intermittent nature of wind power plants

Comparison of two voltage control strategies for a wind power plant

DEFF Research Database (Denmark)

Martinez, Jorge; Kjær, Philip C.; Rodriguez, Pedro

2011-01-01

plants. This paper addresses the analysis of two different voltage control strategies for a wind power plant, i.e. decentralized and centralized voltage control schemes. The analysis has been performed using the equivalent and simplified transfer functions of the system. Using this representation......Larger percentages of wind power penetration translate to more demanding requirements from grid codes. Recently, voltage support at the point of connection has been introduced by several grid codes from around the world, thus, making it important to analyze this control when applied to wind power......, it is possible to investigate the influence of the plant control gain, short circuit ratio, and time delays on the system stability, as well as the fulfillment of the design requirements. The implemented plant voltage control is based on a slope voltage controller, which calculates the references to be sent...

Measuring nuclear power plant output by neutrino detection

International Nuclear Information System (INIS)

Korovkin, V.A.; Kodanev, S.A.; Panashchenko, N.S.; Sokolov, D.A.; Solov'yanov, O.M.; Tverdovskii, N.D.; Yarichin, A.D.; Ketov, S.N.; Kopeikin, V.I.; Machulin, I.N.; Mikaelyan, L.A.; Sinev, V.V.

1989-01-01

Neutrino emission from a reactor is inseparably linked with the fission process of heavy nuclei: each fission contributes a specific amount to the overall power output and gives rise to neutrinos which are emitted by the fission fragments created. Using a detector to record the neutrino flux gives a curve for the number of nuclei undergoing fission and the reactor power output. The question of whether it is practically possible to make use of neutrino emission from reactors was first posed in the mid-70s in connection with preparations for neutrino research at the Roven nuclear power plant (RAES) and in 1986 at an IAEA symposium on the topic of guarantees. Since 1982, research has been carried on at RAES on the fundamental properties and interactions of neutrinos. Based on this research and in parallel with it, in 1983 specialists from the Kurchatov Nuclear Power Institute and RAES jointly conducted an experiment which demonstrated in principle the possibility of remotely measuring reactor power output using the neutrino emission. This experiment had extremely limited statistics and is of interest today as the first demonstration of practical usage of neutrino emission from a reactor. At present the statistics for detecting neutrino events have increased tenfold and experience in lengthy measurements has been accumulated. This allows better analysis for the possibilities of the method. This paper reviews neutrino detection, theoretical bases of the method, determining the fission scale values for converting a number of neutrinos into power output, and measuring the power output

Output power maximization of low-power wind energy conversion systems revisited: Possible control solutions

Energy Technology Data Exchange (ETDEWEB)

Vlad, Ciprian; Munteanu, Iulian; Bratcu, Antoneta Iuliana; Ceanga, Emil [' ' Dunarea de Jos' ' University of Galati, 47, Domneasca, 800008-Galati (Romania)

2010-02-15

This paper discusses the problem of output power maximization for low-power wind energy conversion systems operated in partial load. These systems are generally based on multi-polar permanent-magnet synchronous generators, who exhibit significant efficiency variations over the operating range. Unlike the high-power systems, whose mechanical-to-electrical conversion efficiency is high and practically does not modify the global optimum, the low-power systems global conversion efficiency is affected by the generator behavior and the electrical power optimization is no longer equivalent with the mechanical power optimization. The system efficiency has been analyzed by using both the maxima locus of the mechanical power versus the rotational speed characteristics, and the maxima locus of the electrical power delivered versus the rotational speed characteristics. The experimental investigation has been carried out by using a torque-controlled generator taken from a real-world wind turbine coupled to a physically simulated wind turbine rotor. The experimental results indeed show that the steady-state performance of the conversion system is strongly determined by the generator behavior. Some control solutions aiming at maximizing the energy efficiency are envisaged and thoroughly compared through experimental results. (author)

Output power maximization of low-power wind energy conversion systems revisited: Possible control solutions

International Nuclear Information System (INIS)

Vlad, Ciprian; Munteanu, Iulian; Bratcu, Antoneta Iuliana; Ceanga, Emil

2010-01-01

This paper discusses the problem of output power maximization for low-power wind energy conversion systems operated in partial load. These systems are generally based on multi-polar permanent-magnet synchronous generators, who exhibit significant efficiency variations over the operating range. Unlike the high-power systems, whose mechanical-to-electrical conversion efficiency is high and practically does not modify the global optimum, the low-power systems global conversion efficiency is affected by the generator behavior and the electrical power optimization is no longer equivalent with the mechanical power optimization. The system efficiency has been analyzed by using both the maxima locus of the mechanical power versus the rotational speed characteristics, and the maxima locus of the electrical power delivered versus the rotational speed characteristics. The experimental investigation has been carried out by using a torque-controlled generator taken from a real-world wind turbine coupled to a physically simulated wind turbine rotor. The experimental results indeed show that the steady-state performance of the conversion system is strongly determined by the generator behavior. Some control solutions aiming at maximizing the energy efficiency are envisaged and thoroughly compared through experimental results.

A Statistical Method for Aggregated Wind Power Plants to Provide Secondary Frequency Control

DEFF Research Database (Denmark)

Hu, Junjie; Ziras, Charalampos; Bindner, Henrik W.

2017-01-01

curtailment for aggregated wind power plants providing secondary frequency control (SFC) to the power system. By using historical SFC signals and wind speed data, we calculate metrics for the reserve provision error as a function of the scheduled wind power. We show that wind curtailment can be significantly......The increasing penetration of wind power brings significant challenges to power system operators due to the wind’s inherent uncertainty and variability. Traditionally, power plants and more recently demand response have been used to balance the power system. However, the use of wind power...... as a balancing-power source has also been investigated, especially for wind power dominated power systems such as Denmark. The main drawback is that wind power must be curtailed by setting a lower operating point, in order to offer upward regulation. We propose a statistical approach to reduce wind power...

Coordination Control of a Novel Wind Farm Configuration Including a Hydrogen Storage System and a Gas Turbine

Directory of Open Access Journals (Sweden)

Shihua Xuan

2016-07-01

Full Text Available This paper proposes a novel configuration that combines wind turbines, an electrolyzer, and a gas turbine with the corresponding generator. A control strategy for this configuration is also proposed. The purpose of this configuration and its control strategy is to make the wind farm work like a conventional power plant from a grid’s point of view. The final proposed configuration works properly with the proposed control strategy, the three times per revolution (3p oscillation frequency is removed and the output power fluctuations caused by wind fluctuation are compensated. The final power output of the proposed configuration is constant like that of a conventional power plant, and it can change according to the different requirements of the transmission system operator.

Wind and Photovoltaic Large-Scale Regional Models for hourly production evaluation

DEFF Research Database (Denmark)

Marinelli, Mattia; Maule, Petr; Hahmann, Andrea N.

2015-01-01

This work presents two large-scale regional models used for the evaluation of normalized power output from wind turbines and photovoltaic power plants on a European regional scale. The models give an estimate of renewable production on a regional scale with 1 h resolution, starting from a mesosca...... of the transmission system, especially regarding the cross-border power flows. The tuning of these regional models is done using historical meteorological data acquired on a per-country basis and using publicly available data of installed capacity.......This work presents two large-scale regional models used for the evaluation of normalized power output from wind turbines and photovoltaic power plants on a European regional scale. The models give an estimate of renewable production on a regional scale with 1 h resolution, starting from a mesoscale...

Minimisation of Generation Variability of a Group of Wind Plants

Directory of Open Access Journals (Sweden)

Dubravko Sabolić

2017-09-01

Full Text Available Minimisation of variability of energy delivered from a group of wind plants into the power system using portfolio theory approach was studied. One of the assumptions of that theory is Gaussian distribution of the sample, which is not satisfied in case of wind generation. Therefore, optimisation of a “portfolio” of plants with different goal functions was studied. It was supposed that a decision on distribution of a fixed amount of generation capacity to be installed among a set of geographical locations with known wind statistics is to be made with minimised variability of generation as a goal. In that way the statistical cancellation of variability would be used in the best possible manner. This article is a brief report on results of such an investigation. An example of nine locations in Croatia was used. These locations’ wind statistics are known from historic generation data.

Robust ℋ∞ Dynamic Output Feedback Control Synthesis with Pole Placement Constraints for Offshore Wind Turbine Systems

Directory of Open Access Journals (Sweden)

Tore Bakka

2012-01-01

Full Text Available The problem of robust ℋ∞ dynamic output feedback control design with pole placement constraints is studied for a linear parameter-varying model of a floating wind turbine. A nonlinear model is obtained and linearized using the FAST software developed for wind turbines. The main contributions of this paper are threefold. Firstly, a family of linear models are represented based on an affine parameter-varying model structure for a wind turbine system. Secondly, the bounded parameter-varying parameters are removed using upper bounded inequalities in the control design process. Thirdly, the control problem is formulated in terms of linear matrix inequalities (LMIs. The simulation results show a comparison between controller design based on a constant linear model and a controller design for the linear parameter-varying model. The results show the effectiveness of our proposed design technique.

Power system stabilising features from wind power plants augmented with energy storage

DEFF Research Database (Denmark)

Tarnowski, Germán C.; Kjær, Philip C; Lærke, Rasmus

2014-01-01

This paper describes a wind power plant augmented with energy storage, configured to provide ancillary services (primary reserve, inertial response, power oscillation damping) for enhancement of power system stability. Energy storage can complement wind power plants thus reducing the need for any...... overload or curtailment to allow active power modulation. A 12MW + 1.6MW augmented plant is used for demonstration of representative performance of the particular ancillary service control algorithms...

Power Flow Simulations of a More Renewable California Grid Utilizing Wind and Solar Insolation Forecasting

Science.gov (United States)

Hart, E. K.; Jacobson, M. Z.; Dvorak, M. J.

2008-12-01

Time series power flow analyses of the California electricity grid are performed with extensive addition of intermittent renewable power. The study focuses on the effects of replacing non-renewable and imported (out-of-state) electricity with wind and solar power on the reliability of the transmission grid. Simulations are performed for specific days chosen throughout the year to capture seasonal fluctuations in load, wind, and insolation. Wind farm expansions and new wind farms are proposed based on regional wind resources and time-dependent wind power output is calculated using a meteorological model and the power curves of specific wind turbines. Solar power is incorporated both as centralized and distributed generation. Concentrating solar thermal plants are modeled using local insolation data and the efficiencies of pre-existing plants. Distributed generation from rooftop PV systems is included using regional insolation data, efficiencies of common PV systems, and census data. The additional power output of these technologies offsets power from large natural gas plants and is balanced for the purposes of load matching largely with hydroelectric power and by curtailment when necessary. A quantitative analysis of the effects of this significant shift in the electricity portfolio of the state of California on power availability and transmission line congestion, using a transmission load-flow model, is presented. A sensitivity analysis is also performed to determine the effects of forecasting errors in wind and insolation on load-matching and transmission line congestion.

Harmonic Resonances in Wind Power Plants

DEFF Research Database (Denmark)

Fernandez, Francisco Daniel Freijedo; Chaudhary, Sanjay; Teodorescu, Remus

2015-01-01

This work reviews the state-of-the-art in the field of harmonic resonance problems in Wind Power Plants (WPPs). Firstly, a generic WPP is modeled according to the equivalent circuits of its passive and active components. Main focus is put on modeling active components, i.e. the ones based on power...... converters. Subsequently, pros and cons of frequency and time domain analysis methods are outlined. The next sections are devoted to mitigation methods implemented in the power electronics converters. From the wind turbine perspective, different techniques to enhance the robustness of the controller...... are analyzed. Subsequently, the suitability for active damping of harmonics using STATCOM devices is assessed, with focus both on control techniques and power converter technologies....

Greenhouse gas emissions from operating reserves used to backup large-scale wind power.

Science.gov (United States)

Fripp, Matthias

2011-11-01

Wind farms provide electricity with no direct emissions. However, their output cannot be forecasted perfectly, even a short time ahead. Consequently, power systems with large amounts of wind power may need to keep extra fossil-fired generators turned on and ready to provide power if wind farm output drops unexpectedly. In this work, I introduce a new model for estimating the uncertainty in short-term wind power forecasts, and how this uncertainty varies as wind power is aggregated over larger regions. I then use this model to estimate the reserve requirements in order to compensate for wind forecast errors to a 99.999% level of reliability, and an upper limit on the amount of carbon dioxide that would be emitted if natural gas power plants are used for this purpose. I find that for regions larger than 500 km across, operating reserves will undo 6% or less of the greenhouse gas emission savings that would otherwise be expected from wind power.

Hope for water, wind, and warmth

Energy Technology Data Exchange (ETDEWEB)

Heuseler, H

1974-01-01

Geothermal energy finds its primary applications in the generation of electricity and the heating of homes and office buildings. The largest operational geothermal power plants are those of the Geysers, USA, and Larderello, Italy. The total output of electricity from geothermal sources in 1974 was 10 GW, a small figure compared to the total production of 600 GW. Promising geothermal areas have been discovered along the western edge of the Americas, in eastern Africa, Japan, the Philippines, and in West Germany. Estimates of future development of geothermal energy indicate that 150 GW should be available by 1985, and 500 GW by the year 2000. Small scale wind power plants are in operation in the USA and in Europe. It is estimated that by the turn of the century, the total output from wind sources could be equal to the annual electricity consumption of the USA. Another energy source with significant potential is that associated with ocean tides and currents. A 240 MW tidal power plant is operational at the Rance estuary in France and a second is under construction in the USSR. A system is also under consideration in Brazil. Theoretically, this resource could provide about 5.0 GW/yr. Several systems for the generation of power using ocean thermal gradients are also under study.

Uncertainty Quantification of the Real-Time Reserves for Offshore Wind Power Plants

DEFF Research Database (Denmark)

Göçmen, Tuhfe; Giebel, Gregor; Réthoré, Pierre-Elouan

In order to retain the system stability, the wind power plants are required to provide ancillary services. One of those services is reserve power. Here in this study, we focus on the real-time reserves which can be traded in the balancing markets and are currently used for compensation under...... mandatory downregulation stated by the transmission system operators (TSOs). The PossPOW project (Possible Power of down-regulated Offshore Wind power plants) developed a real-time power curve of available power for offshore wind farms for use during down-regulation. The follow-up Concert project......(control and uncertainties in real-time power curves of offshore wind power plants) aims to quantify and finally reduce the uncertainty in reserve power, bringing the PossPOW algorithm and the state of the art forecasting methods together. The experiments designed to test the available power estimated by the Poss...

The viability of balancing wind generation with large scale energy storage

International Nuclear Information System (INIS)

Nyamdash, Batsaikhan; Denny, Eleanor; O'Malley, Mark

2010-01-01

This paper studies the impact of combining wind generation and dedicated large scale energy storage on the conventional thermal plant mix and the CO 2 emissions of a power system. Different strategies are proposed here in order to explore the best operational strategy for the wind and storage system in terms of its effect on the net load. Furthermore, the economic viability of combining wind and large scale storage is studied. The empirical application, using data for the Irish power system, shows that combined wind and storage reduces the participation of mid-merit plants and increases the participation of base-load plants. Moreover, storage negates some of the CO 2 emissions reduction of the wind generation. It was also found that the wind and storage output can significantly reduce the variability of the net load under certain operational strategies and the optimal strategy depends on the installed wind capacity. However, in the absence of any supporting mechanism none of the storage devices were economically viable when they were combined with the wind generation on the Irish power system. - Research Highlights: → Energy storage would displace the peaking and mid-merit plants generations by the base-load plants generations. Energy storage may negate the CO 2 emissions reduction that is due to the increased wind generations. →Energy storage reduces the variation of the net load. →Under certain market conditions, merchant type energy storage is not viable.

Localization of wind power plants: the aspects of environment and safety

Energy Technology Data Exchange (ETDEWEB)

1982-08-25

The appraisement of the anticipated effects of the wind power on the environment is presented. The following factors are observed: the safety of the plants, noise, infrasound, disturbance of lights and television as well as the effects on nature and birds. Large land based plants with horisontal axis are studied. The risk for a person to be hit by a piece of blade is calculated to 1 x 10 /sup -7/ per million hours. A piece of ice can be thrown up to 250 m in the direction of wind at its highest velocity. The mechanism of nnoise is not well known. The elimination of the disturbance of telecommunication can be attained. Other effects are difficult to quantify and could possibly be manipulated. The distance between human activities and a wind power plant is recommended to be 250 m.

Development of wind power plants in the end of 20th century

International Nuclear Information System (INIS)

Levterov, B.

2003-01-01

I brief review of the use of wind energy worldwide and in Bulgaria is made. Data for operating wind power plants in the world (45 countries are considered) and their electricity production are presented. The situation in Bulgaria in the field of wind energy is also described

Impact of wind power plant reactive current injection during asymmetrical grid faults

DEFF Research Database (Denmark)

Göksu, Ömer; Teodorescu, Remus; Bak, Claus Leth

2013-01-01

As more renewable energy sources, especially more wind turbines (WTs) are installed in the power system; grid codes for wind power integration are being generated to sustain stable power system operation with non-synchronous generation. Common to most of the grid codes, wind power plants (WPPs...... faults, is investigated, which was not considered in the wind power impact studies before....

How Many Model Evaluations Are Required To Predict The AEP Of A Wind Power Plant?

International Nuclear Information System (INIS)

Murcia, J P; Réthoré, P E; Natarajan, A; Sørensen, J D

2015-01-01

Wind farm flow models have advanced considerably with the use of large eddy simulations (LES) and Reynolds averaged Navier-Stokes (RANS) computations. The main limitation of these techniques is their high computational time requirements; which makes their use for wind farm annual energy production (AEP) predictions expensive. The objective of the present paper is to minimize the number of model evaluations required to capture the wind power plant's AEP using stationary wind farm flow models. Polynomial chaos techniques are proposed based on arbitrary Weibull distributed wind speed and Von Misses distributed wind direction. The correlation between wind direction and wind speed are captured by defining Weibull-parameters as functions of wind direction. In order to evaluate the accuracy of these methods the expectation and variance of the wind farm power distributions are compared against the traditional binning method with trapezoidal and Simpson's integration rules.The wind farm flow model used in this study is the semi-empirical wake model developed by Larsen [1]. Three test cases are studied: a single turbine, a simple and a real offshore wind power plant. A reduced number of model evaluations for a general wind power plant is proposed based on the convergence of the present method for each case. (paper)

Butinge Wind Power Plant - Pre-engineering

Energy Technology Data Exchange (ETDEWEB)

Mollestad, Knut A.

1997-03-01

A preliminary study has been done for a wind farm at Butinge in Lithuania consisting of six 600 kW wind turbines. The location of the wind farm is planned near the border with Latvia and near the coast of the Baltic Sea. The preliminary study has through a relatively detailed technical examination of the project, primarily aimed at gathering basic data for budget estimation and cost calculations. Other relevant aspects of the project are also considered. These include an examination of the basis for the project, an analysis of wind conditions, consideration of the various environmental conditions, discussion about the form of organisation and division of responsibility, as well as an examination of the operational and maintenance framework. Based on wind measurements taken at IFE (Institute for Energy Technology), the annual mean wind is estimated to be 7.3 m/s at 45 m height (equivalent to the hub height for the proposed wind turbines). A production calculation has also been done, which shows that the total energy production of the entire wind farm is expected to 9.47 GWh per year. This is equivalent to a use time of 2630 hours respective to a load factor of 30%. The total cost is estimated at 30.2 mill NOK, and the energy price (including operational costs) delivered from the ''power plant wall'', based on this figure and the production estimate, is calculated at 0,32 NOK/kWh. This is based on a lifetime of 20 years for the facility and a 6.5% required rate of return. In addition, there is outlined a possible financial solution based on various price-scenarios and support arrangements. With an equity capital of 8% and 28% external support, the project meets the current energy price in Lithuania (3,4 US cents/kWh). Without support the sales price of the produced energy is increased by approx. 50%. (author)

Coordinated voltage control in offshore HVDC connected cluster of wind power plants

DEFF Research Database (Denmark)

Sakamuri, Jayachandra Naidu; Rather, Zakir Hussain; Rimez, Johan

This paper presents a coordinated voltage control scheme (CVCS) for a cluster of offshore wind power plants connected to a voltage-source converter-based high-voltage direct current system. The primary control point of the proposed voltage control scheme is the introduced Pilot bus, which is having...... by dispatching reactive power references to each wind turbine (WT) in the wind power plant cluster based on their available reactive power margin and network sensitivity-based participation factors, which are derived from the dV/dQ sensitivity of a WT bus w.r.t. the Pilot bus. This method leads...

Modelling and Simulation of VSC-HVDC Connection for Offshore Wind Power Plants

DEFF Research Database (Denmark)

Chaudhary, Sanjay Kumar; Teodorescu, Remus; Rodriguez, Pedro

2010-01-01

Several large offshore wind power plants (WPP) are planned in the seas around Europe. VSC-HVDC is a suitable means of integrating such large and distant offshore WPP which need long submarine cable transmission to the onshore grid. Recent trend is to use large wind turbine generators with full...... scale converters to achieve an optimal operation over a wide speed range. The offshore grid then becomes very much different from the conventional power system grid, in the sense that it is connected to power electronic converters only. A model of the wind power plant with VSC-HVDC connection...

Draft South African wind energy technology platform: preliminary wind energy research and development framework

CSIR Research Space (South Africa)

Szewczuk, S

2011-08-01

Full Text Available The South African Wind Energy Technology Programme (SAWEP) Phase 1 aims to achieve two key strategic outputs that will guide South Africa on wind energy development. One of these outputs is the Wind Atlas for South Africa (WASA) which will play a...

Energy Output Estimation for a Small Wind Turbine Positioned on a Rooftop in the Urban Environment with and without a Duct

DEFF Research Database (Denmark)

Beller, Christina

, the free standing turbines had an energy potential of 300kWh/m2/a for the horizontal axis wind turbine (HAWT) and for the vertical axis wind turbine (VAWT) 180kWh/m2/a. For the ducted turbines an energy output of 180kWh/m2/a was found for the HAWT configuration, while the VAWT configuration reached......Nowadays, wind turbines in general, but also urban wind turbines attained acceptance to a certain extend. Conceptual designs and some examples in reality exist, where small-scale wind turbines have been implemented close to buildings or even integrated in the building structure. This work is aiming...... to estimate how much energy a wind turbine could produce in the built environment, depending on its integration and configuration. On the basis of measurements taken on the rooftop of H.C. Ørsted Institut in Copenhagen, which is located in an urban area, a comparison of fictive free standing turbines...

Coordinated Power Dispatch of a PMSG based Wind Farm for Output Power Maximizing Considering the Wake Effect and Losses

DEFF Research Database (Denmark)

Zhang, Baohua; Hu, Weihao; Hou, Peng

2016-01-01

The energy loss in a wind farm (WF) caused by wake interaction between wind turbines (WTs) is quite high, which can be reduced by proper active power dispatch. The electrical loss inside a WF by improper active power and reactive power dispatch is also considerable. In this paper, a coordinated...... active power and reactive power dispatch strategy is proposed for a Permanent magnet synchronous generator (PMSG) based WF, in order to maximize the total output power by reducing the wake effect and losses inside the devices of the WF, including the copper loss and iron loss of PMSGs, losses inside...

Air emissions due to wind and solar power.

Science.gov (United States)

Katzenstein, Warren; Apt, Jay

2009-01-15

Renewables portfolio standards (RPS) encourage large-scale deployment of wind and solar electric power. Their power output varies rapidly, even when several sites are added together. In many locations, natural gas generators are the lowest cost resource available to compensate for this variability, and must ramp up and down quickly to keep the grid stable, affecting their emissions of NOx and CO2. We model a wind or solar photovoltaic plus gas system using measured 1-min time-resolved emissions and heat rate data from two types of natural gas generators, and power data from four wind plants and one solar plant. Over a wide range of renewable penetration, we find CO2 emissions achieve approximately 80% of the emissions reductions expected if the power fluctuations caused no additional emissions. Using steam injection, gas generators achieve only 30-50% of expected NOx emissions reductions, and with dry control NOx emissions increase substantially. We quantify the interaction between state RPSs and NOx constraints, finding that states with substantial RPSs could see significant upward pressure on NOx permit prices, if the gas turbines we modeled are representative of the plants used to mitigate wind and solar power variability.

How Many Model Evaluations Are Required To Predict The AEP Of A Wind Power Plant?

DEFF Research Database (Denmark)

Murcia Leon, Juan Pablo; Réthoré, Pierre-Elouan; Natarajan, Anand

2015-01-01

(AEP) predictions expensive. The objective of the present paper is to minimize the number of model evaluations required to capture the wind power plant's AEP using stationary wind farm flow models. Polynomial chaos techniques are proposed based on arbitrary Weibull distributed wind speed and Von Misses...... distributed wind direction. The correlation between wind direction and wind speed are captured by defining Weibull-parameters as functions of wind direction. In order to evaluate the accuracy of these methods the expectation and variance of the wind farm power distributions are compared against...... the traditional binning method with trapezoidal and Simpson's integration rules. The wind farm flow model used in this study is the semi-empirical wake model developed by Larsen [1]. Three test cases are studied: a single turbine, a simple and a real offshore wind power plant. A reduced number of model...

Harmonic Active Filtering and Impedance-based Stability Analysis in Offshore Wind Power Plants

DEFF Research Database (Denmark)

Dhua, Debasish; Yang, Guangya; Zhang, Zhe

2017-01-01

installation and provides effectively similar functionality as passive filters. This work is focused on harmonic propagation studies in wind power plants, power quality evaluation at the point of connection and harmonic mitigation by active filtering. Finally, an impedance-based stability analysis......Nowadays, to eliminate harmonics injected by the wind turbines in offshore wind power plants there is a need to install passive filters. Moreover, the passive filters are not adaptive to harmonic profile changes due to topology changes, grid loading etc. Therefore, active filters in wind turbines...... are proposed as a flexible harmonic mitigation measure. The motivation of this study is to explore the possibility of embedding active filtering in wind turbine grid-side converters without having to change the system electrical infrastructure. The active filtering method can prevent additional equipment...

Empirical investigation of wind farm blockage effects in Horn Rev 1 offshore wind farm

DEFF Research Database (Denmark)

Mitraszewski, Karol; Hansen, Kurt Schaldemose; Nygaard, Nicolai

We present an empirical study of wind farm blockage effects based on Horns Rev 1 SCADA data. The mean inflow non-uniformities in wind speed are analyzed by calculating the mean power outputs of turbines located along the outer edges of the farm for different wind directions, wind speeds and stabi......We present an empirical study of wind farm blockage effects based on Horns Rev 1 SCADA data. The mean inflow non-uniformities in wind speed are analyzed by calculating the mean power outputs of turbines located along the outer edges of the farm for different wind directions, wind speeds...

Pumping station design for a pumped-storage wind-hydro power plant

International Nuclear Information System (INIS)

Anagnostopoulos, John S.; Papantonis, Dimitris E.

2007-01-01

This work presents a numerical study of the optimum sizing and design of a pumping station unit in a hybrid wind-hydro plant. The standard design that consists of a number of identical pumps operating in parallel is examined in comparison with two other configurations, using one variable-speed pump or an additional set of smaller jockey pumps. The aim is to reduce the amount of the wind generated energy that cannot be transformed to hydraulic energy due to power operation limits of the pumps and the resulting step-wise operation of the pumping station. The plant operation for a period of one year is simulated by a comprehensive evaluation algorithm, which also performs a detailed economic analysis of the plant using dynamic evaluation methods. A preliminary study of the entire plant sizing is carried out at first using an optimization tool based on evolutionary algorithms. The performance of the three examined pumping station units is then computed and analyzed in a comparative study. The results reveal that the use of a variable-speed pump constitutes the most effective and profitable solution, and its superiority is more pronounced for less dispersed wind power potential

Economic Operation of Power Systems with Significant Wind Power Penetration

DEFF Research Database (Denmark)

Farashbashi-Astaneh, Seyed-Mostafa

This dissertation addresses economic operation of power systems with high penetration of wind power. Several studies are presented to address the economic operation of power systems with high penetration of variable wind power. The main concern in such power systems is high variability...... and unpredictability. Unlike conventional power plants, the output power of a wind farm is not controllable. This brings additional complexity to operation and planning of wind dominant power systems. The key solution in face of wind power uncertainty is to enhance power system flexibility. The enhanced flexibility......, cooperative wind-storage operation is studied. Lithium-Ion battery units are chosen as storage units. A novel formulation is proposed to investigate optimal operation of a storage unit considering power system balancing conditions and wind power imbalances. An optimization framework is presented to increase...

A simulation-based Data Envelopment Analysis (DEA model to evaluate wind plants locations

Directory of Open Access Journals (Sweden)

Hossein Sameie

2015-04-01

Full Text Available As the world is getting overpopulated and over polluted the human being is seeking to utilize new sources of energy that are cleaner, cheaper, and more accessible. Wind is one of these clean energy sources that is accessible everywhere on the planet earth. This source of energy cannot be stored for later use; therefore, environmental circumstances and geographical location of wind plants are crucial matters. This study proposes a model to decide on the optimum location for a wind farm among the demand area. To tackle the uncertainty related to the geographical position of the nominated location such as wind speed; altitude; mean temperature; and humidity; a simulation method is applied on the problem. Other factors such as the time that a plant is out of service and demand fluctuations also have been considered in the simulation phase. Moreover, a probability distribution function is calculated for the turbine power. Then Data Envelopment Analysis (DEA performs the selection between all the nominated locations for wind farm. The proposed model takes into account several important elements of the problems. Elements such as land cost; average power received from the wind blowing; demand point population etc. are considered at the same time to select the optimum location of wind plants. Finally, the model is applied on a real case in order to demonstrate its reliability and applicability.

The importance of flexible power plant operation for Jiangsu's wind integration

DEFF Research Database (Denmark)

Hong, Lixuan; Lund, Henrik; Möller, Bernd

2012-01-01

This paper presents the influence of different regulation strategies on wind energy integration into the existing energy system of Jiangsu. The ability of wind integration is defined in terms of the ability to avoid excess electricity production, to conserve primary energy consumption and to redu...... regulations of Jiangsu’s energy system are compared and analyzed in the range of a wind input from 0% to 42% of the total electricity demand. It is concluded that operating power plants in a flexible way facilitates the promotion of more intermittent wind integration....

A survey on wind power ramp forecasting.

Energy Technology Data Exchange (ETDEWEB)

Ferreira, C.; Gama, J.; Matias, L.; Botterud, A.; Wang, J. (Decision and Information Sciences); (INESC Porto)

2011-02-23

The increasing use of wind power as a source of electricity poses new challenges with regard to both power production and load balance in the electricity grid. This new source of energy is volatile and highly variable. The only way to integrate such power into the grid is to develop reliable and accurate wind power forecasting systems. Electricity generated from wind power can be highly variable at several different timescales: sub-hourly, hourly, daily, and seasonally. Wind energy, like other electricity sources, must be scheduled. Although wind power forecasting methods are used, the ability to predict wind plant output remains relatively low for short-term operation. Because instantaneous electrical generation and consumption must remain in balance to maintain grid stability, wind power's variability can present substantial challenges when large amounts of wind power are incorporated into a grid system. A critical issue is ramp events, which are sudden and large changes (increases or decreases) in wind power. This report presents an overview of current ramp definitions and state-of-the-art approaches in ramp event forecasting.

Grid-connected wind and photovoltaic system

Science.gov (United States)

Devabakthuni, Sindhuja

The objective of this thesis is to design a grid connected wind and photovoltaic system. A new model of converter control was designed which maintains the voltage of the bus to grid as constant when combined system of solar and wind is connected to AC bus. The model is designed to track maximum power at each point irrespective of changes in irradiance, temperature and wind speed which affects the power supplied to grid. Solar power from the sun is not constant as it is affected by changes in irradiances and temperature. Even the wind power is affected by wind speed. A MPPT controller was designed for both systems. A boost converter is designed which uses the pulses from MPPT controller to boost the output. Wind system consists of wind turbine block from the MATLAB with a pitch angle controller to maintain optimum pitch angle. The output from wind turbine is connected to a permanent magnet synchronous generator. The unregulated DC output from the photovoltaic system is directly given to boost converter. The AC output from the wind system is given to an uncontrolled rectifier to get a unregulated DC output. The unregulated DC output goes to the boost converter. A voltage source inverter was designed which converts the rectified DC output from the boost converter to AC power. The inverter is designed to maintain constant AC bus voltage irrespective of the disturbances in the power supply. Photovoltaic and wind systems are individually designed for 5KW each in MATLAB-Simulink environment. In this thesis, the models were subjected to changes in irradiance, temperature and wind speed and the results were interpreted. The model was successful in tracking maximum at every instant and the AC bus voltage was maintained constant throughout the simulation.

Numerical forecast test on local wind fields at Qinshan Nuclear Power Plant

International Nuclear Information System (INIS)

Chen Xiaoqiu

2005-01-01

Non-hydrostatic, full compressible atmospheric dynamics model is applied to perform numerical forecast test on local wind fields at Qinshan nuclear power plant, and prognostic data are compared with observed data for wind fields. The results show that the prognostic of wind speeds is better than that of wind directions as compared with observed results. As the whole, the results of prognostic wind field are consistent with meteorological observation data, 54% of wind speeds are within a factor of 1.5, about 61% of the deviation of wind direction within the 1.5 azimuth (≤33.75 degrees) in the first six hours. (authors)

Cowley Ridge wind plant experiences best production year ever

International Nuclear Information System (INIS)

Anon.

2000-01-01

The Cowley Ridge wind plant in southern Alberta in its fifth year of operation generated 63,380 MWh of electricity, exceeding its annual goal by about 15 per cent. December was one of the highest production months ever. During December the plant operated an an average of 62 per cent capacity throughout the month. The annual average is 35 per cent of capacity

Business case uncertainty of power plants in future energy systems with wind power

International Nuclear Information System (INIS)

Brouwer, Anne Sjoerd; Broek, Machteld van den; Özdemir, Özge; Koutstaal, Paul; Faaij, André

2016-01-01

The European power sector is transforming due to climate policies and an increased deployment of intermittent RES. The sector will require thermal power plants for the decades to come, but their business cases are (negatively) affected by this transformation. This study presents a novel tool to quantify the effect of policy, price and project-related uncertainties on power plant business cases. This tool can support policymakers in stimulating necessary investments in new thermal generation capacity. We find that these investments are currently unsound (power plants recoup on average –12% to 59% of their initial investment). Future climate policy, i.e. the CO_2 price, has a very strong impact on business cases (affects the profitability by 5–40%-points). The impact of the deployment of wind power is average (2–8%-point difference between 10% and 21% wind penetration). Variations in annual wind power production barely affect the profitability (variation of ±1%-point). To stimulate new investments, policymakers should first decrease the uncertainty in business cases caused by policy. Durable climate policy is especially important. Also, policies to increase the profits of thermal power plants should be carefully considered and implemented. This combined approach will reduce the revenue gap that needs to be bridged by supportive policies. - Highlights: • The operation of thermal power plants is affected by CO_2 prices and wind power. • A new tool quantifies the effect of their uncertainty on power plant profitability. • New power plants are unprofitable and show a large spread in expected profits. • Uncertain future climate policy is a key factor in all business cases (±56% change). • Increasing wind power penetration (10–21%) decreases profitability by 14%.

Effects of distributing wind energy generation over Europe

Energy Technology Data Exchange (ETDEWEB)

Giebel, G [Risoe National Lab., Wind Energy and Atmospheric Physics Dept., Roskilde (Denmark)

1999-03-01

Using data from 60 meteorological stations distributed all over Europe in conjunction with the National Grid Model (NGM) from the Rutherford Appleton Laboratory, the effects of the large-scale distribution of wind energy generation are studied. In some regions of Europe, wind energy already covers a significant proportion of the electricity demand. But the intermittence of the wind resource is always a limiting factor when penetration levels are high. Studies for single countries have shown that distributing the generation over a large area reduces the variability of the output and hence makes wind energy more appealing to utilities, since the stability requirement of the network are easier to fulfil. The data are analysed in terms of absolute highs and lows, temporal and spatial correlations. To assess the financial benefits, the NGM is used to evaluate the match of electricity demand and generation as well as the possibel savings of fossil fuel in an electricity grid incorporating various capacities of wind energy generation. To assess the value of wind energy on a trans-national scale, the European plant mix is modelled, and the NGM is used to simulate the scheduling of these plants in the presence of different penetrations of wind energy. (au) EU-JOULE-3. 11 refs.

Maintenance of wind power plants 2011. Abstracts; Instandhaltung von Windenergieanlagen 2011. Vortraege

Energy Technology Data Exchange (ETDEWEB)

NONE

2011-07-01

Within this meeting of the VGB Powertech e.V. (Essen, Federal Republic of Germany) at 23rd to 24th April, 2011 in Hamburg (Federal Republic of Germany) the following lectures were held: (1) Wind Energy in 2020 - Requirements of the Operators (Christoph Kraft); (2) Legal Issues of Maintenance Contracts (Christian Kessel); (3) Service by Whom and to Which Extent - Impact to Project Insurance (Dieter Schimana, Ralf Skowronnek); (4) Maintenance-appropriate Documentation in Conventional Power Plants (Ralf Goers); (5) Fire Protection - Experiences of an Operator (Alfred Kriener); (6) How Fire Fighting in Wind Power Plants Works (Axel Woerner); (7) Comprehensive Fire Protections Systems - a Safety Philosophy to protect Wind Turbines and Substations (Thomas Blum); (8) Online Wear Monitoring (Edwin Becker); (9) Vibration Monitoring on Wind Turbines - Experiences and Results (Michael Wika); (10) SKF Blade Monitoring System (Joerg Lange); (11) Independent, and All-round Carefree with Full Service Concepts (Ulrich Schomakers); (12) Proactive Maintenance Concepts (Axel Schweighardt); (13) Centralized Lubrication for Modern Wind Power Plants (Michael Slembeck); (14) Requirements to inspections and maintenance of WTG from the operators point of view (Konrad Iffarth); (15) O and M-conception for the Offshore-windfarm EnBW Baltic I (Michael Boll); (16) DONG Energy Approach to Offshore O and M (Soeren Dale Padersen); (17) Productivity focused Operations of Offshore Wind Farms (Florian Wuertz); (18) New Momac Offshore Access System (MOTS) - Results of the First Sea Trails (Stefan Leske).

Research on large-scale wind farm modeling

Science.gov (United States)

Ma, Longfei; Zhang, Baoqun; Gong, Cheng; Jiao, Ran; Shi, Rui; Chi, Zhongjun; Ding, Yifeng

2017-01-01

Due to intermittent and adulatory properties of wind energy, when large-scale wind farm connected to the grid, it will have much impact on the power system, which is different from traditional power plants. Therefore it is necessary to establish an effective wind farm model to simulate and analyze the influence wind farms have on the grid as well as the transient characteristics of the wind turbines when the grid is at fault. However we must first establish an effective WTGs model. As the doubly-fed VSCF wind turbine has become the mainstream wind turbine model currently, this article first investigates the research progress of doubly-fed VSCF wind turbine, and then describes the detailed building process of the model. After that investigating the common wind farm modeling methods and pointing out the problems encountered. As WAMS is widely used in the power system, which makes online parameter identification of the wind farm model based on off-output characteristics of wind farm be possible, with a focus on interpretation of the new idea of identification-based modeling of large wind farms, which can be realized by two concrete methods.

Europe's largest solar thermal power plant. [200 kw thermal output supplemented by two 10-kw windmills

Energy Technology Data Exchange (ETDEWEB)

Bossel, U

1976-03-01

An overview is given over the solar heating plant which has recently been commissioned in the Camargue (France). This is the largest plant in Europe, with a mean heat output of about 200 kW, for the production of thermal energy from solar energy. The plant consists of 108 parabolic collectors (200 sq. metres) and 48 flat collectors (110 sq. metres). Two windmills with outputs of 10 kW each complete the system. The heat energy produced by the solar collectors is given up to 3 different stores, which in turn are connected to various consumers.

Design and Analysis of a Slope Voltage Control for a DFIG Wind Power Plant

DEFF Research Database (Denmark)

Martínez, J.; Kjær, P. C.; Rodriguez, Pedro

2012-01-01

This paper addresses a detailed design of a wind power plant and turbine slope voltage control in the presence of communication delays for a wide short-circuit ratio range operation. The implemented voltage control scheme is based upon the secondary voltage control concept, which offers fast...... of connection with the grid. The performance has been tested using PSCAD/EMTDC program. The plant layout used in the simulations is based on an installed wind power plant, composed of 23 doubly fed generator wind turbines. The resulting performance is evaluated using a compilation of grid code voltage control...... response to grid disturbances, despite the communication delays, i.e., this concept is based on a primary voltage control, located in the wind turbine, which follows an external voltage reference sent by a central controller, called secondary voltage control, which is controlling the voltage at the point...

Harmonics in Offshore Wind Power Plants Employing Power Electronic Devices in the Transmission System

DEFF Research Database (Denmark)

Glasdam, Jakob Bærholm

Introduction The trend in power generation is to partly replace conventional power plants with renewable energy sources. Offshore wind power has been selected to take up a significant proportion of the renewable energy production. The grid codes have been updated to accommodate the rising share...... of wind power. The onshore as well as offshore wind power plants (OWPPs) therefore have to meet the same stringent requirement as the conventional power plants. This can be accommodated by employment of flexible alternating current transmission system (FACTS) devices, such as the static compensator...... gives rise to a number of challenges to the wind power industry with regard to construction, installation as well as transmission of the generated energy. The STATCOM and the voltage-sourced converter high-voltage direct current (VSC-HVDC) are attractive solutions for grid connection of remotely located...

Design of a wind turbine-generator system considering the conformability to wind velocity fluctuations

Energy Technology Data Exchange (ETDEWEB)

Wakui, Tetsuya; Hashizume, Takumi; Outa, Eisuke

1999-07-01

The conformability of the rated power output of the wind turbine-generator system and of the wind turbine type to wind velocity fluctuations are investigated with a simulation model. The authors examine three types of wind turbines: the Darrieus-Savonius hybrid, the Darrieus proper and the Propeller. These systems are mainly operated at a constant tip speed ratio, which refers to a maximum power coefficient points. As a computed result of the net extracting power, the Darrieus turbine proper has little conformability to wind velocity fluctuations because of its output characteristics. As for the other turbines, large-scale systems do not always have an advantage over small-scale systems as the effect of its dynamic characteristics. Furthermore, it is confirmed that the net extracting power of the Propeller turbine, under wind direction fluctuation, is much reduced when compared with the hybrid wind turbine. Thus, the authors conclude that the appropriate rated power output of the system exists with relation to the wind turbine type for each wind condition.

Horizontal and vertical wind power plant. Stromerzeugungsanlage durch Windkraft in waagerechter und senkrechter Konstruktion

Energy Technology Data Exchange (ETDEWEB)

Brodersen, K

1976-10-05

Wind power machines and associated generating equipment are exposed to the effects of the weather, which causes high maintenance and repair costs. The construction of the wind blades causes turbulence, which has an adverse effect of the efficiency of this plant. The purpose of the invention is therefore to make the construction of the generating equipment such that the protection of the unit and the armature against effects from the weather and greater efficiency are achieved with low plant, maintenance and repair costs. According to the invention, the problem is solved by having the wall of the central room, for pressure and guidance, reinforced at the top, where the guides also provide security against the tilting torque and ensure protection of the unit and armature against effects from the weather. In order to avoid turbulence on the wind blades, a seamless joint between the wind blades and the wind guide surface is provided above the centre of rotation, whereby the stability and free length of the wind blades are increased. The whole plant can be fabricated in a factory and can be transported to the site by helicopters.

Overview of FACTS devices for wind power plants directly connected to the transmission network

DEFF Research Database (Denmark)

Adamczyk, Andrzej Grzegorz; Teodorescu, Remus; Rodriguez, Pedro

2010-01-01

Growing number of wind turbines is changing electricity generation profile all over the world. This brings challenges for power system operation, which was designed and developed around conventional power plants with directly coupled synchronous generators. In result, safety and stability...... of the electrical network with high wind energy penetration might be compromised. For this reason transmission system operators (TSO) impose more stringent connection requirements on the wind power plant (WPP) owners. On the other hand flexible AC transmission systems (FACTS) devices offer enhancement of grid...... research in FACTS applicability for WPPs is summarized. Examples of few existing FACTS applications for wind farms are given....

A 3 MW wind power plant at Maglarp in Sweden

International Nuclear Information System (INIS)

Koc, B.

1991-01-01

The wind power plant at Maglarp, in a frequented region of Sweden, is described. Its technical parameters are given and its environmental impacts are dealt with. The whiz of the rotor blades is heard at a distance of 500 to 1000 m; the author refers to the whiz as pleasant. Not a single bird has been found killed by the facility. Interference with the TV signal can at times be observed in the town; this is more marked with metal rotor blades than with blades made of reinforced plastic. A wing of the wind power plant concentrates on its surface an energy of about 20 kW per square meter. (M.D.)

Using hydropower to complement wind energy: a hybrid system to provide firm power

Energy Technology Data Exchange (ETDEWEB)

Jaramillo, O.A.; Borja, M.A.; Huacuz, J.M. [Instituto de Investigaciones Electricas, Morelos (Mexico). Energias No Convencionales

2004-09-01

This paper presents a theoretical study of how wind power can be complemented by hydropower. A conceptual framework is provided for a hybrid power station that produces constant power output without the intermittent fluctuations inherent when using wind power. Two hypothetical facilities are considered as case studies. One of them is a hydropower plant located on the ''Presidente Benito Juarez'' dam in Jalapa del Marques, Oaxaca, Mexico. The other hypothetical facility is a wind farm located near ''La Venta's', an area in Juchitan, Oaxaca, Mexico. The wind-hydro-power system is a combined wind and hydro power plant in a region that is rich in both resources. The model shows that the hybrid plant could provide close to 20 MW of firm power to the electrical distribution system. On a techno-economic basis, we obtain the levelized production cost of the hybrid system. Taking into account two different discount rates of 7% and 10%, figures for levelized production cost are developed. (author)

Power system integration of VSC-HVDC connected offshore wind power plants

DEFF Research Database (Denmark)

Zeni, Lorenzo; Kjær, Philip Carne

This report presents an overview of challenges and solutions for the integration into the power system of offshore wind power plants (WPPs) connected to onshore grids through a voltage-source converter based high voltage direct current (VSC-HVDC) transmission system. Aspects that are touched upon...... of the network in the vicinity of the HVDC station and (iii) limiting characteristics of WPPs such as inherent control and communication delays, presence of mechanical resonances at the same frequency as POD and active power ramp-rate limitations. Clustering of wind power plants The proof of concept...... introduction to justify the study, describe the state-of-art and formulate the project’s objectives, the report is essentially divided into three parts, as follows. Control principles of offshore AC networks The control of offshore AC networks relies purely on power electronics, especially if Type 4 wind...

77 FR 485 - Wind Plant Performance-Public Meeting on Modeling and Testing Needs for Complex Air Flow...

Science.gov (United States)

2012-01-05

... DEPARTMENT OF ENERGY Office of Energy Efficiency and Renewable Energy Wind Plant Performance... and on-shore utility-scale wind power plants. DOE is requesting this information to support the development of cost-effective wind power deployment. DATES: The meeting will be held Tuesday, January 17, 2012...

Electrical Structure of Future Off-shore Wind Power Plant with a High Voltage Direct Current Power Transmission

DEFF Research Database (Denmark)

Sharma, Ranjan

The increasing demand of electric power and the growing consciousness towards the changing climate has led to a rapid development of renewable energy in the recent years. Among all, wind energy has been the fastest growing energy source in the last decade. But the growing size of wind power plants......, better wind conditions at off-shore and the general demand to put them out of sight have all contributed to the installation of large wind power plants in off-shore condition. However, moving wind power plants far out in the off-shore comes with many associated problems. One of the main challenges...... is the transmission of power over long distance. Historically, the power transmission from off-shore wind power plants has been done via HVAC submarine cables. This provides a simple solution, but AC cables cannot be arbitrarily long. It is shown in the report that major issues with HVAC cable transmission system...

Decision 2010-021 : TransAlta Wind Ardenville wind plant and substation : application no. 1604970, proceeding ID 260

International Nuclear Information System (INIS)

2010-01-01

TransAlta Wind, a wholly owned subsidiary of TransAlta Corporation, filed an application in April 2009 to construct and operate the Ardenville wind farm and substation in Alberta. The wind farm consists of 23 wind turbines, each rated at 3 MW, for a total installed capacity of 69 MW. The wind farm would be connected to the Alberta Interconnected Electric System at the substation. TransAlta anticipates that a new 138-kV transmission line will be required and has contacted the transmission facilities for the future applications. The Alberta Utilities Commission issued a notice to all interested parties and landholders within 2 km of the proposed wind farm. Two residents raised concerns regarding the use of fossil fuels and alternative fuels, ecological impacts and aesthetic impacts of wind farms and land values. Upon review of information, the Commission was satisfied that approval of the application was in the public interest and that the wind farm complies with all regulatory requirements, including sound levels. Pursuant to sections 11, 14 and 15 of the Hydro and Electric Energy Act, the Commission approved the application and granted approval to TransAlta Wind to construct and operate the Ardenville wind power plant and substation.

Large-scale integration of wind power into power systems as well as on transmission networks for offshore wind power plants. Proceedings

Energy Technology Data Exchange (ETDEWEB)

Betancourt, Uta; Ackermann, Thomas (eds.)

2013-11-01

This proceedings contains contributions to the followings main topics: Grid integration experiences; Flexibility and economics of integration; Voltage control issues; Offshore wind power plants; Forecasting; Grid code issues; HVDC connection issues; Frequency control issues; National grid's perspective; Power system balancing; Power system issues; New grid and generators issues; Flexibility with storage and demand side management; AC connected offshore wind power plants; Economic and market issues; Modelling issues; Offshore grid issues.

Technical Description Lillgrund Wind Power Plant. Lillgrund Pilot Project

Energy Technology Data Exchange (ETDEWEB)

Jeppsson, Joakim; Larsen, Poul Erik; Larsson, Aake [Vattenfall Vindkraft AB, Stockholm (Sweden)

2008-09-15

Lillgrund offshore wind power plant comprises 48 wind turbines, each rated at 2.3 MW, bringing the total wind farm capacity to 110 MW. The Lillgrund offshore wind power plant is located in a shallow area of Oeresund, 7 km off the coast of Sweden and 7 km south from the Oeresund Bridge connecting Sweden and Denmark. An average wind speed of around 8,5 m/s at hub height, combined with a relatively low water depth of 4 to 8 meters makes it economically feasible to build here. Vattenfall Vindkraft AB is the owner and operator of Lillgrund offshore wind power plant. Lillgrund is a Swedish pilot project supported by the Swedish Energy Agency. The bidding process was completed during 2005 and the offshore power plant was constructed in the period 2006 to 2007. The wind farm was constructed on time and has now been successfully operational since December 2007. There is, however, always potential for improvement and the aim of this report has been to determine and highlight these areas. It is worth noting out that only the electrical system and the foundations are tailor made at offshore wind power plants. The wind turbines are more or less standard products with none or very limited possibilities for project specific design changes. Geotechnical investigations are expensive and it can be difficult to balance the risks as well as the benefits of this expense in the early phases of a large infrastructure project. As a whole, the geotechnical surveys at Lillgrund proved to be useful. They identified potential issues, such as the fact that extra excavation was required for two of the foundations. It also revealed the location of a small number of boulders that would have to be removed. Vattenfall requested a complete study of the electrical system for Lillgrund to be delivered with the bids. That request was not met. Instead Siemens Wind Power began a complete electrical system study after being awarded the Contract. The electrical system study was completed during the

Wind plant capacity credit variations: A comparison of results using multiyear actual and simulated wind-speed data

Energy Technology Data Exchange (ETDEWEB)

Milligan, M.R. [National Renewable Energy Lab., Golden, CO (United States)

1997-12-31

Although it is widely recognized that variations in annual wind energy capture can be significant, it is not clear how significant this effect is on accurately calculating the capacity credit of a wind plant. An important question is raised concerning whether one year of wind data is representative of long-term patterns. This paper calculates the range of capacity credit measures based on 13 years of actual wind-speed data. The results are compared to those obtained with synthetic data sets that are based on one year of data. Although the use of synthetic data sets is a considerable improvement over single-estimate techniques, this paper finds that the actual inter-annual variation in capacity credit is still understated by the synthetic data technique.

Wind Turbine Providing Grid Support

DEFF Research Database (Denmark)

2011-01-01

changing the operation of the wind turbine to a more efficient working point.; When the rotational speed of the rotor reaches a minimum value, the wind turbine enters a recovery period to re-accelerate the rotor to the nominal rotational speed while further contributing to the stability of the electrical......A variable speed wind turbine is arranged to provide additional electrical power to counteract non-periodic disturbances in an electrical grid. A controller monitors events indicating a need to increase the electrical output power from the wind turbine to the electrical grid. The controller...... is arranged to control the wind turbine as follows: after an indicating event has been detected, the wind turbine enters an overproduction period in which the electrical output power is increased, wherein the additional electrical output power is taken from kinetic energy stored in the rotor and without...

China Wind Power Outlook 2010

International Nuclear Information System (INIS)

Junfeng, Li; Pengfei, Shi; Hu, Gao

2010-10-01

China's wind power can reach 230 GW of installed capacity by 2020, which is equal to 13 times the current capacity of the Three Gorges Dam; its annual electricity output of 464.9 TWh could replace 200 coal fire power plants. In 2009, China led the world in newly installed wind-energy devices, reaching a capacity of 13.8 GW (10,129 turbines) - a rate of one new turbine every hour. In terms of overall capacity, China ranks second, at 25.8 GW. The report projects that by 2020, China's total wind power capacity will reach at least 150GW, possibly up to 230GW, which, if realized, could cut 410 million tons of CO2 emission, or 150 million tons of coal consumption. Compared to multinationals, many Chinese companies are young and lack a strong basis for research and development. Despite a renewable energy policy requiring grid companies to purchase all electricity from wind farms, access to wind power for the grid is frequently lagging behind an unstable, out-dated grid infrastructure. There is also the problem of a lack of incentives and penalties for grid companies, and slow progress in more wind energy technologies.

Adaptive output-based command shaping for sway control of a 3D overhead crane with payload hoisting and wind disturbance

Science.gov (United States)

Abdullahi, Auwalu M.; Mohamed, Z.; Selamat, H.; Pota, Hemanshu R.; Zainal Abidin, M. S.; Ismail, F. S.; Haruna, A.

2018-01-01

Payload hoisting and wind disturbance during crane operations are among the challenging factors that affect a payload sway and thus, affect the crane's performance. This paper proposes a new online adaptive output-based command shaping (AOCS) technique for an effective payload sway reduction of an overhead crane under the influence of those effects. This technique enhances the previously developed output-based command shaping (OCS) which was effective only for a fixed system and without external disturbances. Unlike the conventional input shaping design technique which requires the system's natural frequency and damping ratio, the proposed technique is designed by using the output signal and thus, an online adaptive algorithm can be formulated. To test the effectiveness of the AOCS, experiments are carried out using a laboratory overhead crane with a payload hoisting in the presence of wind, and with different payloads. The superiority of the method is confirmed by 82% and 29% reductions in the overall sway and the maximum transient sway respectively, when compared to the OCS, and two robust input shapers namely Zero Vibration Derivative-Derivative and Extra-Insensitive shapers. Furthermore, the method demonstrates a uniform crane's performance under all conditions. It is envisaged that the proposed method can be very useful in designing an effective controller for a crane system with an unknown payload and under the influence of external disturbances.

Mortality of radio collared willow ptarmigan in Smoela wind-power plant

Energy Technology Data Exchange (ETDEWEB)

Pedersen, Hans Chr.; Broeseth, Henrik; Nilsen, Erlend B.; Sandercock, Brett K.; Bevanger, Kjetil

2011-07-01

Full text: In the project Pre- and post-construction studies of conflicts between birds and wind turbines in coastal Norway (BirdWind), Smoela willow ptarmigan (Lagopus lagopus variegatus) has been one of the species studied. This sub-species represent gallinaceous birds, known to be bad flyers susceptible to collide with artificial structures, e.g. power lines. However, the possible impact of a wind-power plant on survival and behaviour in a willow ptarmigan population was unknown. The objectives of the study were therefore rather wide; to study direct and indirect effects of wind turbines on willow ptarmigan behaviour, habitat selection, reproduction and survival in areas where wind-power plants are established. To collect data on habitat selection, movements, collision risks, avoidance behaviour, survival and general population dynamic parameters, willow ptarmigan were radio-tagged in 2008-2010, using traditional VHF-transmitters (Holohill) with mortality switch, necklace mount, 12 g, lasting for approximately 24 months. Due to low population density and only occasional snow cover, a method using strong lights, dipnet and car was used to catch birds. In total, 34 willow ptarmigan were caught (19 males and 15 females). All birds were caught inside the wind-power plant area (WPA). The birds were radio-tracked at irregular intervals and almost all birds, when found, was located within the WPA. All carcasses of dead birds were examined. When possible, cause of death was determined as; predation (raptor), collision, unknown, other. In total, 28 of the radio-tagged birds have died since January 2008. A Kaplan-Meier analysis of cumulative survival rates, show an exceptionally low survival (<30%). Unlike other willow ptarmigan populations most of the mortality takes place during winter, from December throughout March. Although a thorough analysis of mortality causes has yet not been carried out, a majority of the birds have probably been killed by avian predators and to

On the equivalence of the solar wind coupling parameter ε and the magnetospheric energy output parameter UT during intense geomagnetic storms

International Nuclear Information System (INIS)

Gonzalez, W.D.; Gonzalez, A.L.C.; Tsurutani, B.T.

1990-01-01

For intervals with intense geomagnetic activity it is shown that the solar wind coupling parameter ε and the magnetospheric output parameter U T are equivalent and that ranges of values of ε can be set up in terms of values of the ring current-time constant τ. (author)

Active current control in wind power plants during grid faults

DEFF Research Database (Denmark)

Martinez, Jorge; Kjær, Phillip C.; Rodriguez, Pedro

2010-01-01

Modern wind power plants are required and designed to ride through faults in electrical networks, subject to fault clearing. Wind turbine fault current contribution is required from most countries with a high amount of wind power penetration. In order to comply with such grid code requirements......, wind turbines usually have solutions that enable the turbines to control the generation of reactive power during faults. This paper addresses the importance of using an optimal injection of active current during faults in order to fulfil these grid codes. This is of relevant importance for severe...... faults, causing low voltages at the point of common coupling. As a consequence, a new wind turbine current controller for operation during faults is proposed. It is shown that to achieve the maximum transfer of reactive current at the point of common coupling, a strategy for optimal setting of the active...

Introduction Of Wavestar Wave Energy Converters At The Danish Offshore Wind Power Plant Horns Rev 2

DEFF Research Database (Denmark)

Marquis, L.; Kramer, Morten; Kringelum, J.

is to be connected to a wind turbine at the DONG Energy owned wind power plant Horns Rev 2 placed off the western coast of Denmark. The plant delivers its energy production to a transformer station owned by Energinet.dk. Energinet.dk has the obligation to ensure that power is transmitted to the Danish consumers...... with this combination. This can increase the value of the produced power from future wind/wave plants. Further potential synergies of combining wind and wave energy in the same area include increased energy production from the available area and sharing of infrastructure costs as well as O&M facilities. In a future....... If Executed the project will be the first one in the world where wind and wave power are combined at full scale. The goal of the project is to evaluate the opportunities of combining wind and wave energy production on a commercial scale and to demonstrate the reduction of energy fluctuations...

The “Weather Intelligence for Renewable Energies” Benchmarking Exercise on Short-Term Forecasting of Wind and Solar Power Generation

DEFF Research Database (Denmark)

Sperati, Simone; Alessandrini, Stefano; Pinson, Pierre

2015-01-01

the power output of two wind farms and two photovoltaic power plants, in order to compare the merits of forecasts based on different modeling approaches and input data. It was thus possible to obtain a better knowledge of the state of the art in both wind and solar power forecasting, with an overview...

Application of the Aero-Hydro-Elastic Model, HAWC2-WAMIT, to Offshore Data from Floating Power Plants Hybrid Wind- and Wave-Energy Test Platform, P37

DEFF Research Database (Denmark)

Bellew, Sarah; Yde, Anders; Verelst, David Robert

2014-01-01

numerical models, which can combine the aerodynamic, hydrodynamic, structural exibility and mooring components. Very little oshore data exists, however, in order to validate these numerical models. Floating Power Plant are the developers of a oating, hybrid wind- and wave-energy device. The device uses...... the pitching wave energy devices, not only to increase and smooth the power output from the platform, but also to take the energy from the waves in a controlled manner, resulting in a stable platform for the wind turbine and a safe harbour for O&M. They are currently developing the nal design for their rst...... full-scale prototype, the P80, which has a width of 80 m. As part of the development, Floating Power Plant have completed 4 oshore test-phases (totalling over 2 years oshore operation) on a 37 m wide scaled test device, the P37. This paper focuses on the comparison of one of the leading numerical...

Performance of Generating Plant: Managing the Changes. Part 3: Renewable energy plant: reports on wind, photovoltaics and biomas energies

Energy Technology Data Exchange (ETDEWEB)

Manoha, Bruno; Cohen, Martin [Electricite de France (France)

2008-05-15

The WEC Committee on the Performance of Generating Plant (PGP) has been collecting and analysing power plant performance statistics worldwide for more than 30 years and has produced regular reports, which include examples of advanced techniques and methods for improving power plant performance through benchmarking. A series of reports from the various working groups was issued in 2008. This reference presents the results of Working Group 3 (WG3). WG3 will promote the introduction of performance indicators for renewable energy generating plant (wind, geothermal, solar and biomass) developed by the Committee. It will also assess selected transitional technology issues and environmental factors related to non-conventional technologies. The WG3 report includes sections on Wind Energy Today, Photovoltaics Energy Today, Biomass Electricity Today and appendices.

Applying micro scales of horizontal axis wind turbines for operation in low wind speed regions

International Nuclear Information System (INIS)

Pourrajabian, Abolfazl; Ebrahimi, Reza; Mirzaei, Masoud

2014-01-01

Highlights: • Three micro-turbines with output power less than 1 kW were designed for operation in low wind speed regions. • In addition to the output power, starting time was considered as a key parameter during the design. • The effects of generator resistive torque and number of blades on the performance of the turbines were investigated. - Abstract: Utilizing the micro scales of wind turbines could noticeably supply the demand for the electricity in low wind speed regions. Aerodynamic design and optimization of the blade, as a main part of a wind turbine, were addressed in the study. Three micro scales of horizontal axis wind turbines with output power of 0.5, 0.75 and 1 kW were considered and the geometric optimization of the blades in terms of the two involved parameters, chord and twist, was undertaken. In order to improve the performance of the turbines at low wind speeds, starting time was included in an objective function in addition to the output power – the main and desirable goal of the wind turbine blade design. A purpose-built genetic algorithm was employed to maximize both the output power and the starting performance which were calculated by the blade-element momentum theory. The results emphasize that the larger values of the chord and twist at the root part of the blades are indispensable for the better performance when the wind speed is low. However, the noticeable value of the generator resistive torque could largely delay the starting of the micro-turbines especially for the considered smaller size, 0.5 kW, where the starting aerodynamic torque could not overcome the generator resistive torque. For that size, an increase in the number of blades improved both the starting performance and also output power

Experimental investigation on the wake interference among wind turbines sited in atmospheric boundary layer winds

Institute of Scientific and Technical Information of China (English)

W. Tian; A. Ozbay; X. D. Wang; H.Hu

2017-01-01

We examined experimentally the effects of incom-ing surface wind on the turbine wake and the wake interfer-ence among upstream and downstream wind turbines sited in atmospheric boundary layer (ABL) winds. The experi-ment was conducted in a large-scale ABL wind tunnel with scaled wind turbine models mounted in different incom-ing surface winds simulating the ABL winds over typical offshore/onshore wind farms. Power outputs and dynamic loadings acting on the turbine models and the wake flow char-acteristics behind the turbine models were quantified. The results revealed that the incoming surface winds significantly affect the turbine wake characteristics and wake interference between the upstream and downstream turbines. The velocity deficits in the turbine wakes recover faster in the incoming surface winds with relatively high turbulence levels. Varia-tions of the power outputs and dynamic wind loadings acting on the downstream turbines sited in the wakes of upstream turbines are correlated well with the turbine wakes charac-teristics. At the same downstream locations, the downstream turbines have higher power outputs and experience greater static and fatigue loadings in the inflow with relatively high turbulence level, suggesting a smaller effect of wake inter-ference for the turbines sited in onshore wind farms.

Impact of Wind Power Plants with Full Converter Wind Turbines on Power System Small-Signal Stability

DEFF Research Database (Denmark)

Knüppel, Thyge; Nygaard Nielsen, Jørgen; Dixon, Andrew

Wind power is being developed in power systems all around the world, and already today wind power covers more than 20 % of the electricity consumption in some countries. As the size of each wind power plant (WPP) increases and as the levels of penetration reaches certain magnitudes, the inclusion...... of the dynamic properties of the WPPs in the power system stability studies become important. The work presented in this report deal with the impact of WPPs based on full converter wind turbines (WTs) on the power system small-signal rotor angle stability. During small disturbances in the power system, the rotor...... speed of the synchronous machines will eventually return to its steady state if the power system is small-signal stable. The dynamic properties of a WPP are fundamentally dierent from those of a synchronous machine, and the interaction of WPPs with the synchronous machines in power system oscillations...

Application of data mining methods for power forecast of wind power plants

Energy Technology Data Exchange (ETDEWEB)

Arnoldt, Alexander; Koenig, Stefan; Bretschneider, Peter [Fraunhofer Institute for Optronics, System Technology, and Image Exploitation - Application Centre System Technology (IOSB-AST), Ilmenau (Germany). Energy Systems Group; Mikut, Ralf [Karlsruhe Institute of Technology (KIT), Eggenstein-Leopoldshafen (DE). Inst. for Applied Computer Science (IAI)

2010-07-01

Since the last decade power systems underlie a drastic change due to increased exploitation of renewable energy resources (RES) such as wind and photovoltaic power plants. A result of this process is a significant increase of fluctuating generation in low, middle and high voltage grids. Consequently, impacts on short and middle term capacity planning of power plants occur and must be handled to avoid imbalances between generation and demand at any time. Therefore, forecasts of wind and photovoltaic generation play a very important role. Quality improvements potentially ease planning and lead to cost reductions. This work investigated the dependencies of input parameters. The optimal parameter selection was achieved through application of data mining methods. Finally, the wind power prediction was demonstrated with Artificial Neural Networks and Physical Models. (orig.)

Behavior of a nuclear power plant ventilation stack for wind loads

International Nuclear Information System (INIS)

Venkatachalapathy, V.

2012-01-01

This paper describes behavior of self supporting tall reinforced concrete (RC) ventilation stack of a nuclear power plant (NPP) for wind loads. Since the static and equivalent dynamic wind loads are inter-dependant on overall size of the stack, proper sizing of the stack geometry is important for reducing wind loads. The present study investigated the influence of engineered backfill soil on lateral response of ventilation stack. Ignoring backfill soil stiffness up to ground height does not allow to predict actual critical wind velocity causing across wind oscillation. The results show that proposed modification in the stack geometry modeled using 2D beam-spring elements is economical than that of single tapered geometry. Shaft diameter reduced in the proposed geometry indicates that there is a scope for overall space savings in the NPP layout. (author)

Implications of environmental regulation and coal plant retirements in systems with large scale penetration of wind power

International Nuclear Information System (INIS)

Rahmani, Mohsen; Jaramillo, Paulina; Hug, Gabriela

2016-01-01

Over the last decade there have been a growing number of federal and state regulations aimed at controlling air emissions at power plants and/or increasing the penetration of renewable resources in the grid. Environmental Protection Agency regulations will likely lead to the retrofit, retirement, or replacement of coal-fired power plants while the state Renewable Portfolio Standards will continue to drive large-scale deployment of renewable energy sources, primarily wind. Combined, these changes in the generation fleet could have profound implications for the operations of the power system. In this paper, we aim to better understand the interaction between coal plant retirements and increased levels of wind power. We extensively analyze the operations of the PJM electricity system under a broad set of scenarios that include varying levels of wind penetration and coal plant retirements. Not surprisingly, we find that without transmission upgrades, retirement of coal-fired power plants will likely result in considerable transmission congestion and higher energy prices. Increased wind penetration, with high geographic diversity, could mitigate some of the negative effects of coal plant retirement and lead to a significant reduction in air emissions, but wind forecast error might impose operational constraints on the system at times of peak load. - Highlights: •Retirement of coal plants may increase transmission congestion and LMP prices. •EPA rules might lead to significant reductions in emission of air pollutants. •Wind geographical diversity may reduce transmission constraints and air emissions. •At times of high peak load, wind may not reduce system stress caused by retirement. •RPS policies can support and mitigate negative impacts of EPA regulations.

Input-output model of regional environmental and economic impacts of nuclear power plants

International Nuclear Information System (INIS)

Johnson, M.H.; Bennett, J.T.

1979-01-01

The costs of delayed licensing of nuclear power plants calls for a more-comprehensive method of quantifying the economic and environmental impacts on a region. A traditional input-output (I-O) analysis approach is extended to assess the effects of changes in output, income, employment, pollution, water consumption, and the costs and revenues of local government disaggregated among 23 industry sectors during the construction and operating phases. Unlike earlier studies, this model uses nonlinear environmental interactions and specifies environmental feedbacks to the economic sector. 20 references

LCA of electricity systems with high wind power penetration

DEFF Research Database (Denmark)

Turconi, Roberto; O' Dwyer, C. O.; Flynn, D.

Electricity systems are shifting from being based on fossil fuels towards renewable sources to enhance energy security and mitigate climate change. However, by introducing high shares of variable renewables - such as wind and solar - dispatchable power plants are required to vary their output...... to fulfill the remaining electrical demand, potentially increasing their environmental impacts [1,2]. In this study the environmental impacts of potential short-term future electricity systems in Ireland with high shares of wind power (35-50% of total installed capacity) were evaluated using life cycle...... considered: while not outweighing the benefits from increasing wind energy, cycling emissions are not negligible and should thus be systematically included (i.e. by using emission factors per unit of fuel input rather than per unit of power generated). Cycling emissions increased with the installed wind...

Optimal operation of a pumped-storage hydro plant that compensates the imbalances of a wind power producer

OpenAIRE

Duque, Álvaro Jaramillo; Castronuovo, Edgardo D.; Sánchez, Ismael; Usaola, Julio

2011-01-01

The participation of wind energy in electricity markets requires providing a forecast for future energy production of a wind generator, whose value will be its scheduled energy. Deviations from this schedule because of prediction errors could imply the payment of imbalance costs. In order to decrease these costs, a joint operation between a wind farm and a hydro-pump plant is proposed; the hydro-pump plant changes its production to compensate wind power prediction errors. In order to optimize...

Development of a Wind Plant Large-Eddy Simulation with Measurement-Driven Atmospheric Inflow

Energy Technology Data Exchange (ETDEWEB)

Quon, Eliot W.; Churchfield, Matthew J.; Cheung, Lawrence; Kern, Stefan

2017-01-09

This paper details the development of an aeroelastic wind plant model with large-eddy simulation (LES). The chosen LES solver is the Simulator for Wind Farm Applications (SOWFA) based on the OpenFOAM framework, coupled to NREL's comprehensive aeroelastic analysis tool, FAST. An atmospheric boundary layer (ABL) precursor simulation was constructed based on assessments of meteorological tower, lidar, and radar data over a 3-hour window. This precursor was tuned to the specific atmospheric conditions that occurred both prior to and during the measurement campaign, enabling capture of a night-to-day transition in the turbulent ABL. In the absence of height-varying temperature measurements, spatially averaged radar data were sufficient to characterize the atmospheric stability of the wind plant in terms of the shear profile, and near-ground temperature sensors provided a reasonable estimate of the ground heating rate describing the morning transition. A full aeroelastic simulation was then performed for a subset of turbines within the wind plant, driven by the precursor. Analysis of two turbines within the array, one directly waked by the other, demonstrated good agreement with measured time-averaged loads.

Wind Power Development and Energy Storage under China’s Electricity Market Reform—A Case Study of Fujian Province

Directory of Open Access Journals (Sweden)

Dunguo Mou

2018-01-01

Full Text Available This paper, based on the Fujian provincial 500 kV grid and part of the 220 kV grid and the key power plants, including hydro, coal, nuclear, gas, wind and pumping and storage hydro powers (PSHP connected to the grid, constructs an independent electricity market model. Using data that are very close to reality about coal fired power production costs, along with data about power plants’ technical constraints, this paper studies the effect of wind power on Fujian’s provincial electricity market. Firstly, the paper analyzes the relationship between wind speed and wind power output and the effects of short-term power output fluctuation on frequency modulation and voltage regulation. Secondly, under supposition of the production costs following quadratic functions, the paper analyzes the effects of changes in wind power output on the electricity supply costs under optimal power flow. Thirdly, using the bidding model in the Australian Electricity Market Operator for reference and supposing that, in a competitive market, coal fired power plants can bid 6 price bands according to their capacity, the paper analyzes effects of wind power on electricity prices under optimal power flow, the stabilizing effects of PSHP and the minimum PSHP capacity needed to stabilize the electricity market. Finally, using a daily load curve, this paper simulates the electricity prices’ fluctuation under optimal power flow and PSHP’s stabilizing effect. The results show that, although PSHP has a large external social welfare effect, it can hardly make a profit. In the end, this paper puts forward some policy suggestions for Fujian province’s wind and nuclear power development, PSHP construction and electricity market development.

Application of Portfolio Theory to Minimization of Generation Variability in a System with Wind plants

International Nuclear Information System (INIS)

Sabolic, D.

2016-01-01

This paper evaluates validity of modern portfolio theory (MPT) for planning of installation of new wind plants with the lowest possible generation variability for given expected yearly generation. Suppose a Planner had historic meteorological data on wind speeds at a finite number of locations over longer time periods, and that they were technically convertible to time series of forecasted generation powers per megawatt of installed capacity. Suppose further that she intended to upgrade existing system with certain fixed amount of new wind plant capacity. Then she would be able to allocate shares in that total capacity to the available locations in a way that suits her policy goals regarding relation between total expected annual generation and total variability of generation best. Minimization of variability is a legitimate policy goal because it increases total costs of energy supply, so that leaving generation to vary more than technically necessary is economically inefficient. This article focuses on applicability of portfolio theory to such a problem. In the presented research, measured 15-minute data of wind generation in existing Croatian wind plants were used.(author).

Challenges, problems and possible solutions in wind generator systems from the aspect of forecast, planning and delivery of wind energy

International Nuclear Information System (INIS)

Giovski, Nikola

2014-01-01

The fundamental difficulties of integrating wind energy into the power system arise from its large temporal variability and limited predictability. That's why the integration of wind power presents major challenge for today's operating and planning practices of the power system operators. Accurate predictions of the possible wind power output, in time intervals relevant for creating schedules for production and exchange capacity, allows to system operators and dispatching personnel more efficient power system management. Despite the challenges and problems that arise due to integration of wind power into power systems, which need to be solved or reduced, wind power has its advantages that should be utilized. The effective integration of wind power plants into the transmission grid should allow them to represent the backbone of future energy systems. Modern wind generators represent production units that have the ability to participate in the management of energy systems e.g. in the regulation of frequency, voltage and other network operating requirements. This paper provides a brief overview of global experiences with the challenges, problems and possible solutions that appear in wind generator systems from the aspect of forecasting, planning and delivery of wind energy. (author)

An approach to evaluating alternatives for wind power plant locations

Directory of Open Access Journals (Sweden)

Rehman, Ateekh Ur

2016-12-01

Full Text Available Multi-criteria decision approaches are preferred for achieving multi-dimensional sustainable renewable energy goals. A more critical issue faced by the wind power industry is the selection of a location to tap prospective energy, which needs to be evaluated on multiple measures. In this paper, the aim is to assess and rank alternative wind power plant locations in Saudi Arabia. The approach presented here takes multiple criteria into consideration, such as wind speed, wind availability, site advantages, terrain details, risk and uncertainty, technology used, third party support, projected demand, types of customers, and government policies. A comparative analysis of feasible alternatives that satisfy all multi- criteria objectives is carried out. The results obtained are subjected to sensitivity analysis. Concepts such as ‘threshold values’ and ‘attribute weights’ make the approach more sensitive.

Wind Turbine Test. Wind Matic WM 17S

DEFF Research Database (Denmark)

Friis Pedersen, Troels

The report describes standard measurements performed on a Wind-Matic WM 17S, 75 kW wind turbine. The measurements carried out and reported here comprises the power output, system efficiency, energy production, transmission efficiency, rotor power, rotor efficiency, air-brakes efficiency, structural...

Wind Turbine Test Wind Matic WM 15S

DEFF Research Database (Denmark)

Friis Pedersen, Troels

The report describes standard measurements performed on a Wind-Matic WM 15S, 55 kW wind turbine. The measurements carried out and reported here comprises the power output, system efficiency, energy production, transmission efficiency, rotor power, rotor efficiency, air-brakes efficiency, dynamical...

Conceptual evaluation of hybrid energy system comprising wind-biomass-nuclear plants for load balancing and for production of renewable synthetic transport fuels

International Nuclear Information System (INIS)

Carlsson, Johan; Purvins, Arturs; Papaioannou, Ioulia T.; Shropshire, David; Cherry, Robert S.

2014-01-01

Future energy systems will increasingly need to integrate variable renewable energy in order to reduce greenhouse gas emissions from power production. Addressing this trend the present paper studies how a hybrid energy systems comprising aggregated wind farms, a biomass processing plant, and a nuclear cogeneration plant could support high renewable energy penetration. The hybrid energy system operates so that its electrical output tends to meet demand. This is achieved mainly through altering the heat-to-power ratio of the nuclear reactor and by using excess electricity for hydrogen production through electrolysis. Hybrid energy systems with biomass treatment processes, i.e. drying, torrefaction, pyrolysis and synthetic fuel production were evaluated. It was shown that the studied hybrid energy system comprising a 1 GWe wind farm and a 347 MWe nuclear reactor could closely follow the power demand profile with a standard deviation of 34 MWe. In addition, on average 600 m"3 of bio-gasoline and 750 m"3 bio-diesel are produced daily. The reduction of greenhouse gas emissions of up to 4.4 MtCO_2eq annually compared to power generation and transport using conventional fossil fuel sources. (author)

Wind lens technology and its application to wind and water turbine and beyond

Directory of Open Access Journals (Sweden)

Ohya Yuji

2017-01-01

Full Text Available Wind lens is a new type of wind power system consisting of a simple brimmed ring structure that surrounds the rotor causing greater wind to pass through the turbine. As a consequence, the turbine's efficiency of capturing energy from the wind gets dramatically increased. A Wind lens turbine can generate 2–5 times the power of an existing wind turbine given at the same rotor diameter and incoming wind speed. This fluid dynamical effect is also effective in the water. We have developed 1–3 kW Wind lens turbines and a 100 kW Wind lens turbine. In addition to the enhanced output power, Wind lens turbine is quiet. The technology is now used in an offshore experiment with a hexagonal float 18 meters in diameter set off the coast of Hakata Bay in Fukuoka City. Moreover, we are now pursuing larger size Wind lens turbines through multi-rotor design consisting of multiple Wind lens turbines in a same vertical plane to embody larger total power output.

Output power control of two coupled wind generators

Directory of Open Access Journals (Sweden)

A Boukhelifa

2016-09-01

Full Text Available In this paper we are interested to the power control of two wind generators coupled to the network through power converters. Every energy chain conversion is composed of a wind turbine, a gearbox, a Double Fed Induction Generator (DFIG, two PWM converters and a DC bus. The power exchange and the DC voltage are controlled by the use of proportional integral correctors. For our study, initially we have modeled all the components of the one system energy conversion, and then we have simulated its behavior using Matlab/Simulink. In another part of this paper we present the analysis of the interaction and the powerflow between the two aerogenerators following a disturbance due to wind speed on every turbine. Also we have considered a connection fault to the DC bus. In each case the assessment of power brought into play is checked. Simulation tests are established.

Aspects of Wind Power Plant Collector Network Layout and Control Architecture

DEFF Research Database (Denmark)

Altin, Müfit; Teodorescu, Remus; Bak-Jensen, Birgitte

2010-01-01

ecent developments in wind turbine technology go towards the installation of larger Wind Power Plants (WPPs) both onshore and offshore. As wind power penetration level increases, power system operators are challenged by the penetration impacts to maintain reliability and stability of power system....... Therefore, connection topology and control concepts of large WPPs should be carefully investigated to improve the overall performance of both the WPP and the power systems. This paper aims to present a general overview of the design considerations for the electrical layout of WPPs and the WPP control...... strategy for optimum power generation while fulfilling the power system operators requirements....

A desalination plant with solar and wind energy

International Nuclear Information System (INIS)

Chen, H; Ye, Z; Gao, W

2013-01-01

The shortage of freshwater resources has become a worldwide problem. China has a water shortage, although the total amount of water resources is the sixth in the world, the per capita water capacity is the 121th (a quarter of the world's per capita water capacity), and the United Nations considers China one of the poorest 13 countries in the world in terms of water. In order to increase the supply of fresh water, a realistic way is to make full use of China's long and narrow coastline for seawater desalination. This paper discusses a sea water desalination device, the device adopts distillation, uses the greenhouse effect principle and wind power heating principle, and the two-type start is used to solve the problem of vertical axis wind turbine self-starting. Thrust bearings are used to ensure the stability of the device, and to ensure absorbtion of wind energy and solar energy, and to collect evaporation of water to achieve desalination. The device can absorb solar and wind energy instead of input energy, so it can be used in ship, island and many kinds of environment. Due to the comprehensive utilization of wind power and solar power, the efficiency of the device is more than other passive sea water desalting plants, the initial investment and maintenance cost is lower than active sea water desalting plant. The main part of the device cannot only be used in offshore work, but can also be used in deep sea floating work, so the device can utilise deep sea energy. In order to prove the practicability of the device, the author has carried out theory of water production calculations. According to the principle of conservation of energy, the device ais bsorbing solar and wind power, except loose lost part which is used for water temperature rise and phase transition. Assume the inflow water temperature is 20 °C, outflow water temperature is 70 °C, the energy utilization is 60%, we can know that the water production quantity is 8 kg/ m 2 per hour. Comparing

Low-Carbon Economic Dispatching for Power Grid Integrated with Carbon Capture Power Plants and Wind Power System

Directory of Open Access Journals (Sweden)

Sheng Siqing

2015-01-01

Full Text Available Carbon emission characteristics of all kinds of power units are analyzed against the background of the low carbon economy. This paper introduces carbon trading in the dispatching model, gives full consideration to the benefit or cost of carbon emission and introduces carbon emission in the dispatching model as a decision variable so as to achieve the unity of the economy and the environmental protection of the dispatching model. A low carbon economic dispatching model is established based on multiple objectives, such as the lowest thermal power generation cost, the lowest carbon trading cost and the lowest carbon capture power plant operation cost. Load equalization, output constraint of power unit, ramping constraint, spinning reserve constraint and carbon capture efficiency constraint should be taken into account in terms of constraint conditions. The model is solved by the particle swarm optimization based on dynamic exchange and density distance. The fact that the introduction of carbon trading can effectively reduce the level of carbon emission and increase the acceptance level of wind power is highlighted through the comparison of the results of three models’ computational examples. With the carbon trading mechanism, carbon capture power plants with new technologies are able to give full play to the advantage of reducing carbon emission and wind curtailment so as to promote the development of the energy conservation and emission reduction technology and reduce the total cost of the dispatching system.

Operation and sizing of energy storage for wind power plants in a market system

International Nuclear Information System (INIS)

Korpaas, M.; Holen, A.T.

2003-01-01

This paper presents a method for the scheduling and operation of energy storage for wind power plants in electricity markets. A dynamic programming algorithm is employed to determine the optimal energy exchange with the market for a specified scheduling period, taking into account transmission constraints. During operation, the energy storage is used to smooth variations in wind power production in order to follow the scheduling plan. The method is suitable for any type of energy storage and is also useful for other intermittent energy resources than wind. An application of the method to a case study is also presented, where the impact of energy storage sizing and wind forecasting accuracy on system operation and economics are emphasized. Simulation results show that energy storage makes it possible for owners of wind power plants to take advantage of variations in the spot price, by thus increasing the value of wind power in electricity markets. With present price estimates, energy storage devices such as reversible fuel cells are likely to be a more expensive alternative than grid expansions for the siting of wind farms in weak networks. However, for areas where grid expansions lead to unwanted interference with the local environment, energy storage should be considered as a reasonable way to increase the penetration of wind power. (author)

Opportunity study and a business plan for a wind power plant

International Nuclear Information System (INIS)

Nikolov, Marjan; Naumov, Risto

2006-01-01

This paper provides illustration of opportunity study and a business plan for utilizing the wind renewable resource for electricity production in Macedonia. The study is prepared under UNIDO recommendations for feasibility studies (see [1]) and following the IAS, by Marjan Nikolov and Risto Naumov. This is a project simulation for a small wind farm comprising 3 power plant units. We use price list from 'Proven Engineering Products Ltd' UK.

Optimal and Modular Configuration of Wind Integrated Hybrid Power Plants for Off-Grid Systems

DEFF Research Database (Denmark)

Petersen, Lennart; Iov, Florin; Tarnowski, German Claudio

2018-01-01

This paper focusses on the system configuration of offgrid hybrid power plants including wind power generation. First, a modular and scalable system topology is proposed. Secondly, an optimal sizing algorithm is developed in order to determine the installed capacities of wind turbines, PV system......, battery energy storage system and generator sets. The novelty of this work lies in a robust sizing algorithm with respect to the required resolution of resource data in order to account for intra-hour power variations. Moreover, the involvement of the electrical infrastructure enables a precise estimation...... of power losses within the hybrid power plant as well as the consideration of both active and reactive power load demand for optimally sizing the plant components. The main outcome of this study is a methodology to determine feasible system configurations of modular and scalable wind integrated hybrid...

Harmonic Mitigation Methods in Large Offshore Wind Power Plants

DEFF Research Database (Denmark)

Kocewiak, Łukasz Hubert; Chaudhary, Sanjay; Hesselbæk, Bo

2013-01-01

Various sources of harmonic problems in large wind power plants (WPPs) and optimized harmonic mitigation methods are presented in this paper. The harmonic problems such as sources of harmonic emission and amplification as well as harmonic stability are identified. Also modern preventive...... and remedial harmonic mitigation methods in terms of passive and active filtering are described. It is shown that WPP components such as long HVAC cables and park transformers can introduce significant low-frequency resonances which can affect wind turbine control system operation and overall WPP stability...... as well as amplification of harmonic distortion. It is underlined that there is a potential in terms of active filtering in modern grid-side converters in e.g. wind turbines, STATCOMs or HVDC stations utilized in modern large WPPs. It is also emphasized that the grid-side converter controller should...

DFIG-based offshore wind power plant connected to a single VSC-HVDC operated at variable frequency: Energy yield assessment

International Nuclear Information System (INIS)

De-Prada-Gil, Mikel; Díaz-González, Francisco; Gomis-Bellmunt, Oriol; Sumper, Andreas

2015-01-01

The existence of HVDC (High Voltage Direct Current) transmission systems for remote offshore wind power plants allows devising novel wind plant concepts, which do not need to be synchronized with the main AC grid. This paper proposes an OWPP (offshore wind power plant) design based on variable speed wind turbines driven by DFIGs (doubly fed induction generators) with reduced power electronic converters connected to a single VSC-HVDC converter which operates at variable frequency and voltage within the collection grid. It is aimed to evaluate the influence of the power converter size and wind speed variability within the WPP on energy yield efficiency, as well as to develop a coordinated control between the VSC-HVDC converter and the individual back-to-back reduced power converters of each DFIG-based wind turbine in order to provide control capability for the wind power plant at a reduced cost. To maximise wind power generation by the OWPP, an optimum electrical frequency search algorithm for the VSC-HVDC converter is proposed. Both central wind power plant control level and local wind turbine control level are presented and the performance of the system is validated by means of simulations using MATLAB/Simulink ® . - Highlights: • Influence of converter size and wind speed variability on energy capture efficiency. • Coordinated control between a VSC-HVDC and DFIG WTs with reduced power converters. • Static and dynamic analysis of the performance of the implemented control scheme. • Optimal variable frequency operation to maximize WPP generation at a reduced cost

Transients in VSC-HVDC connected offshore wind power plant

DEFF Research Database (Denmark)

El-Khatib, Walid Ziad; Schwartzberg, D.; Arana Aristi, I.

2015-01-01

The focus of this paper is transient phenomena in VSC-HVDC connected offshore wind power plants (WPPs). With the help of a case study modelled in PSCAD simulation software, energisation events are analysed in the time domain. A comparison with more well-known results obtained at energisation of AC...

China Wind Power Outlook 2010

Energy Technology Data Exchange (ETDEWEB)

Junfeng, Li; Pengfei, Shi; Hu, Gao [Chinese Renewable Energy Industries Association CREIA, Beijing (China)

2010-10-15

China's wind power can reach 230 GW of installed capacity by 2020, which is equal to 13 times the current capacity of the Three Gorges Dam; its annual electricity output of 464.9 TWh could replace 200 coal fire power plants. In 2009, China led the world in newly installed wind-energy devices, reaching a capacity of 13.8 GW (10,129 turbines) - a rate of one new turbine every hour. In terms of overall capacity, China ranks second, at 25.8 GW. The report projects that by 2020, China's total wind power capacity will reach at least 150GW, possibly up to 230GW, which, if realized, could cut 410 million tons of CO2 emission, or 150 million tons of coal consumption. Compared to multinationals, many Chinese companies are young and lack a strong basis for research and development. Despite a renewable energy policy requiring grid companies to purchase all electricity from wind farms, access to wind power for the grid is frequently lagging behind an unstable, out-dated grid infrastructure. There is also the problem of a lack of incentives and penalties for grid companies, and slow progress in more wind energy technologies.

Coordinated control of wind power plants in offshore HVDC grids

DEFF Research Database (Denmark)

Sakamuri, Jayachandra N.

2017-01-01

power between different countries, and different synchronous areas. It is very likely that they will then be combined with offshore wind power plant (OWPP) connections in the North Sea, transforming it in a multi terminal DC (MTDC) grid and, therefore, in a fully meshed offshore DC grid in near future......During the recent years, there has been a significant penetration of offshore wind power into the power system and this trend is expected to continue in the future. The North Sea in Europe has higher potential for offshore wind power; therefore, the North Seas Countries' Offshore Grid initiative....... However, increased penetration of offshore wind power into the power system poses several challenges to its security. This thesis deals with two main research challenges, (1) Develop, and analyze the coordinated control strategies for AC voltage and reactive power control in the cluster of OWPPs connected...

Experimental results of wind powered pumping plant with electrical transmission

International Nuclear Information System (INIS)

Falchetta, M.; Prischich, D.; Benedetti, A.; Cara, G.

1992-01-01

A demonstrative application of deep well pumping system employing a wind powered pumping plant with an electric transmission was set-up and tested for two years at the test field of the Casaccia center of ENEA (Italian Agency for Energy, New Technologies and the Environment), near Rome. The tests permitted the evaluation of the practical performance, advantages and drawbacks of a wind pumping plant of this type, in order to permit a design optimization and a proper choice of components and of control strategies for future commercial applications. The main point of investigation was the evaluation of the effectiveness of a control scheme based on a 'permanent link' between electric generator and electric motor, avoiding any electronics and switching components, and leading to a very robust and reliable means of transferring energy to the pump at variable speed, and at low cost

Pumped storage in systems with very high wind penetration

International Nuclear Information System (INIS)

Tuohy, A.; O'Malley, M.

2011-01-01

This paper examines the operation of the Irish power system with very high levels of wind energy, with and without pumped storage. A unit commitment model which accounts for the uncertainty in wind power is used. It is shown that as wind penetration increases, the optimal operation of storage depends on wind output as well as load. The main benefit from storage is shown to be a decrease in wind curtailment. The economics of the system are examined to find the level at which storage justifies its capital costs and inefficiencies. It is shown that the uncertainty of wind makes the option of storage more attractive. The size of the energy store has an impact on results. At lower levels of installed wind (up to approximately 50% of energy from wind in Ireland), the reduction in curtailment is insufficient to justify building storage. At greater levels of wind, storage reduces curtailment sufficiently to justify the additional capital costs. It can be seen that if storage replaces OCGTs in the plant mix instead of CCGTs, then the level at which it justifies itself is lower. Storage increases the level of carbon emissions at wind penetration below 60%. - Research highlights: → Examines operation of pumped storage unit in a system with levels of wind from 34%-68% of energy. → High capital cost of storage is not justified until system has high (approx. 45%) wind penetration. → Results are driven by the amount of wind curtailment avoided and plant mix of system. → Other flexible options (e.g. interconnection) offer many of the same benefits as storage.

BUeV recommendations for supervision of onshore wind energy plants; BUeV-Empfehlungen fuer die Ueberwachung von Windenergieanlagen

Energy Technology Data Exchange (ETDEWEB)

Jaeppelt, Ulrich [WTM Engineers, Beratende Ingenieure im Bauwesen, Hamburg (Germany); Harte, Reinhard [Bergische Univ. Wuppertal (Germany). Lehr- und Forschungsgebiet Statik und Dynamik der Tragwerke

2012-08-15

In the last two decades, the sector of wind energy plants has grown rapidly and therefore enabled also a dynamic development of relevant technologies. Initiated by revision of the Renewable Energy Law as well as by the expiration of the approved life of first generation plants, the replacement of ancient wind energy plants has gained increasing significance. Increasing rotor diameters and tower heights lead additionally to new demands on structural engineers, checking engineers and supervisors. In the attached text recommendations of the Bau-Ueberwachungsverein BUeV regarding site supervision and periodic inspections of onshore wind energy plants are presented. (orig.)

Solar-wind system powers mountain clean-up

Energy Technology Data Exchange (ETDEWEB)

NONE

2001-03-01

By using a hybrid solar-wind system, the Japanese have tackled the problem of human excrement left by tourists in mountain lodges and in natural parks by installing flush toilets and wastewater treatment plants. The solar array (4.9 kW{sub p}) consists of 76 panels of single-crystal photovoltaic cells each with an output of 64 Wp. The wind turbines (total capacity 2.1 kW) operate whatever the wind strength or direction. Storage batteries prevent any dip in power which would result from low ambient temperatures. The system can still function at temperatures as low as minus 25{sup o}C. Between November and April when the lodge is closed, the waste is decomposed biologically. A block diagram shows the elements of the system, and details of cost are given. The system won the 1999 New Energy Award.

Coupling a Mesoscale Numerical Weather Prediction Model with Large-Eddy Simulation for Realistic Wind Plant Aerodynamics Simulations (Poster)

Energy Technology Data Exchange (ETDEWEB)

Draxl, C.; Churchfield, M.; Mirocha, J.; Lee, S.; Lundquist, J.; Michalakes, J.; Moriarty, P.; Purkayastha, A.; Sprague, M.; Vanderwende, B.

2014-06-01

Wind plant aerodynamics are influenced by a combination of microscale and mesoscale phenomena. Incorporating mesoscale atmospheric forcing (e.g., diurnal cycles and frontal passages) into wind plant simulations can lead to a more accurate representation of microscale flows, aerodynamics, and wind turbine/plant performance. Our goal is to couple a numerical weather prediction model that can represent mesoscale flow [specifically the Weather Research and Forecasting model] with a microscale LES model (OpenFOAM) that can predict microscale turbulence and wake losses.

An index guiding temporal planting policies for wind erosion reduction

NARCIS (Netherlands)

Zhao, C.X.; Zheng, D.W.; Stigter, C.J.; He, W.Q.; Tuo, D.B.; Zhao, P.

2006-01-01

Vegetation cover has spatial as well as temporal characteristics, but the latter are often neglected. Temporal cover characteristics were explored to recommend planting policies for returning arable land into land better protected from serious wind erosion during late autumn, winter, and

Life cycle cost analysis of wind power considering stochastic uncertainties

International Nuclear Information System (INIS)

Li, Chiao-Ting; Peng, Huei; Sun, Jing

2014-01-01

This paper presents a long-term cost analysis of wind power and compares its competitiveness to non-renewable generating technologies. The analysis considers several important attributes related to wind intermittency that are sometimes ignored in traditional generation planning or LCOE (levelized cost of energy) studies, including the need for more nameplate capacity due to intermittency, hourly fluctuations in wind outputs and cost for reserves. The competitiveness of wind power is assessed by evaluating four scenarios: 1) adding natural gas generating capacity to the power grid; 2) adding coal generating capacity to the power grid; 3) adding wind capacity to the power grid; and, 4) adding wind capacity and energy storage to the power grid where an energy storage device is used to cover wind intermittency. A case study in the state of Michigan is presented to demonstrate the use of the proposed methodology, in which a time horizon from 2010 to 2040 is considered. The results show that wind energy will still be more expensive than natural gas power plants in the next three decades, but will be cheaper than coal capacities if wind intermittency is mitigated. Furthermore, if the costs of carbon emissions and environmental externalities are considered, wind generation will be a competitive option for grid capacity expansion. - Highlights: • The competitiveness of wind power is analyzed via life cycle cost analysis. • Wind intermittency and reserve costs are explicitly considered in the analysis. • Results show that wind is still more expensive than natural gas power plants. • Wind can be cheaper than coal capacities if wind intermittency is mitigated. • Wind will be competitive if costs of carbon emissions are considered

Using wind plant data to increase reliability.

Energy Technology Data Exchange (ETDEWEB)

Peters, Valerie A. (Sandia National Laboratories, Livermore, CA); Ogilvie, Alistair B.; McKenney, Bridget L.

2011-01-01

Operators interested in improving reliability should begin with a focus on the performance of the wind plant as a whole. To then understand the factors which drive individual turbine performance, which together comprise the plant performance, it is necessary to track a number of key indicators. Analysis of these key indicators can reveal the type, frequency, and cause of failures and will also identify their contributions to overall plant performance. The ideal approach to using data to drive good decisions includes first determining which critical decisions can be based on data. When those required decisions are understood, then the analysis required to inform those decisions can be identified, and finally the data to be collected in support of those analyses can be determined. Once equipped with high-quality data and analysis capabilities, the key steps to data-based decision making for reliability improvements are to isolate possible improvements, select the improvements with largest return on investment (ROI), implement the selected improvements, and finally to track their impact.

Impact of Negative Sequence Current Injection by Wind Power Plants

DEFF Research Database (Denmark)

Chaudhary, Sanjay; Göksu, Ömer; Teodorescu, Remus

2013-01-01

This paper presents an analysis of the impact from negative sequence current injection by wind power plants in power systems under steady-state and short-term unbalanced conditions, including faults. The separate positive and negative sequence current control capability of the grid-side converters...... of full scale converter type wind turbines may be utilized to alter voltage imbalance at the point of connection and further into the grid, in turn changing the resultant negative sequence current flow in the grid. The effects of such control actions have been analyzed and discussed through theoretical...

Releasable Kinetic Energy-Based Inertial Control of a DFIG Wind Power Plant

DEFF Research Database (Denmark)

Lee, Jinsik; Muljadi, Eduard; Sørensen, Poul Ejnar

2016-01-01

Wind turbine generators (WTGs) in a wind power plant (WPP) contain different levels of releasable kinetic energy (KE) because of the wake effects. This paper proposes a releasable KE-based inertial control scheme for a doubly fed induction generator (DFIG) WPP that differentiates the contributions....... The proposed scheme adjusts the two loop gains in a DFIG controller depending on its rotor speed so that a DFIG operating at a higher rotor speed releases more KE. The performance of the proposed scheme was investigated under various wind conditions. The results clearly indicate that the proposed scheme...

Power fluctuation and power loss of wind turbines due to wind shear and tower shadow

Institute of Scientific and Technical Information of China (English)

Binrong WEN; Sha WEI; Kexiang WEI; Wenxian YANG; Zhike PENG; Fulei CHU

2017-01-01

The magnitude and stability of power output are two key indices of wind turbines.This study investigates the effects of wind shear and tower shadow on power output in terms of power fluctuation and power loss to estimate the capacity and quality of the power generated by a wind turbine.First,wind speed models,particularly the wind shear model and the tower shadow model,are described in detail.The widely accepted tower shadow model is modified in view of the cone-shaped towers of modem large-scale wind turbines.Power fluctuation and power loss due to wind shear and tower shadow are analyzed by performing theoretical calculations and case analysis within the framework of a modified version of blade element momentum theory.Results indicate that power fluctuation is mainly caused by tower shadow,whereas power loss is primarily induced by wind shear.Under steady wind conditions,power loss can be divided into wind farm loss and rotor loss.Wind farm loss is constant at 3α(3α-1)R2/(8H2).By contrast,rotor loss is strongly influenced by the wind turbine control strategies and wind speed.That is,when the wind speed is measured in a region where a variable-speed controller works,the rotor loss stabilizes around zero,but when the wind speed is measured in a region where the blade pitch controller works,the rotor loss increases as the wind speed intensifies.The results of this study can serve as a reference for accurate power estimation and strategy development to mitigate the fluctuations in aerodynamic loads and power output due to wind shear and tower shadow.

Wind turbine power tracking using an improved multimodel quadratic approach.

Science.gov (United States)

Khezami, Nadhira; Benhadj Braiek, Naceur; Guillaud, Xavier

2010-07-01

In this paper, an improved multimodel optimal quadratic control structure for variable speed, pitch regulated wind turbines (operating at high wind speeds) is proposed in order to integrate high levels of wind power to actively provide a primary reserve for frequency control. On the basis of the nonlinear model of the studied plant, and taking into account the wind speed fluctuations, and the electrical power variation, a multimodel linear description is derived for the wind turbine, and is used for the synthesis of an optimal control law involving a state feedback, an integral action and an output reference model. This new control structure allows a rapid transition of the wind turbine generated power between different desired set values. This electrical power tracking is ensured with a high-performance behavior for all other state variables: turbine and generator rotational speeds and mechanical shaft torque; and smooth and adequate evolution of the control variables. 2010 ISA. Published by Elsevier Ltd. All rights reserved.

Development of a Wind Plant Large-Eddy Simulation with Measurement-Driven Atmospheric Inflow: Preprint

Energy Technology Data Exchange (ETDEWEB)

Quon, Eliot; Churchfield, Matthew; Cheung, Lawrence; Kern, Stefan

2017-02-01

This paper details the development of an aeroelastic wind plant model with large-eddy simulation (LES). The chosen LES solver is the Simulator for Wind Farm Applications (SOWFA) based on the OpenFOAM framework, coupled to NREL's comprehensive aeroelastic analysis tool, FAST. An atmospheric boundary layer (ABL) precursor simulation was constructed based on assessments of meteorological tower, lidar, and radar data over a 3-hour window. This precursor was tuned to the specific atmospheric conditions that occurred both prior to and during the measurement campaign, enabling capture of a night-to-day transition in the turbulent ABL. In the absence of height-varying temperature measurements, spatially averaged radar data were sufficient to characterize the atmospheric stability of the wind plant in terms of the shear profile, and near-ground temperature sensors provided a reasonable estimate of the ground heating rate describing the morning transition. A full aeroelastic simulation was then performed for a subset of turbines within the wind plant, driven by the precursor. Analysis of two turbines within the array, one directly waked by the other, demonstrated good agreement with measured time-averaged loads.

9{sup th} international workshop on large-scale integration of wind power into power systems as well as on transmission networks for offshore wind power plants. Proceedings

Energy Technology Data Exchange (ETDEWEB)

Betancourt, Uta; Ackermann, Thomas (eds.)

2010-07-01

Within the 9th International Workshop on large-scale integration of wind power into power systems as well as on transmission networks for offshore wind power plants at 18th to 19th October, 2010 in Quebec (Canada), lectures and poster papers were presented to the following themes: (1) Keynote session and panel; (2) European grid integration studies; (3) Modeling; (4) Wind forecasting; (5) North American grid integration studies; (6) Voltage stability and control; (7) Grid codes and impact studies; (8) Canadian University research (WESNet); (9) Operation and dispatch; (9) Offshore wind power plants; (10) Frequency Control; (11) Methodologies to estimate wind power impacts on power systems, summaries from IEAWIND collaboration; (12) HVDC; (13) Grid codes and system impact studies; (14) Modeling and validation; (15) Regulations, markets and offshore wind energy; (16) Integration issues; (17) Wind turbine control system; (18) Energy management and IT solutions.

Reactive power control of wind farm using facts devices

International Nuclear Information System (INIS)

Ashfaq, S.; Arif, A.; Shakeel, A.; Mahmood, T.

2014-01-01

Wind energy is an attainable option to complement other types of pollution-free green generation Grid connections of renewable energy resources are vital if they are to be effectively exploited, but grid connection brings problems of voltage fluctuation and harmonic distortion. FACTs devices are one of the power electronics revolutions to improve voltage profile, system stability, and reactive power control and to reduce transmission losses. The studied system here is a variable speed wind generation system based on Induction Generator (IG) with integration of different FACTs controllers in the wind farm. To harness the wind power efficiently the most reliable and expensive system in the present era is grid connected doubly fed induction generator. Induction generator with FACTs devices is a suitable economical replacement. The suggested scheme is implemented in MATLAB Simulink with real time parameters of GHARO wind power plant in Sind, and corresponding results and output waveforms proves the potential strength of proposed methodology. (author)

Optimization-based reactive power control in HVDC-connected wind power plants

OpenAIRE

Schönleber, Kevin; Collados Rodríguez, Carlos; Teixeira Pinto, Rodrigo; Ratés Palau, Sergi; Gomis Bellmunt, Oriol

2017-01-01

One application of high–voltage dc (HVdc) systems is the connection of remotely located offshore wind power plants (WPPs). In these systems, the offshore WPP grid and the synchronous main grid operate in decoupled mode, and the onshore HVdc converter fulfills the grid code requirements of the main grid. Thus, the offshore grid can be operated independently during normal conditions by the offshore HVdc converter and the connected wind turbines. In general, it is well known that optimized react...

Wind power error estimation in resource assessments.

Directory of Open Access Journals (Sweden)

Osvaldo Rodríguez

Full Text Available Estimating the power output is one of the elements that determine the techno-economic feasibility of a renewable project. At present, there is a need to develop reliable methods that achieve this goal, thereby contributing to wind power penetration. In this study, we propose a method for wind power error estimation based on the wind speed measurement error, probability density function, and wind turbine power curves. This method uses the actual wind speed data without prior statistical treatment based on 28 wind turbine power curves, which were fitted by Lagrange's method, to calculate the estimate wind power output and the corresponding error propagation. We found that wind speed percentage errors of 10% were propagated into the power output estimates, thereby yielding an error of 5%. The proposed error propagation complements the traditional power resource assessments. The wind power estimation error also allows us to estimate intervals for the power production leveled cost or the investment time return. The implementation of this method increases the reliability of techno-economic resource assessment studies.

Wind power error estimation in resource assessments.

Science.gov (United States)

Rodríguez, Osvaldo; Del Río, Jesús A; Jaramillo, Oscar A; Martínez, Manuel

2015-01-01

Estimating the power output is one of the elements that determine the techno-economic feasibility of a renewable project. At present, there is a need to develop reliable methods that achieve this goal, thereby contributing to wind power penetration. In this study, we propose a method for wind power error estimation based on the wind speed measurement error, probability density function, and wind turbine power curves. This method uses the actual wind speed data without prior statistical treatment based on 28 wind turbine power curves, which were fitted by Lagrange's method, to calculate the estimate wind power output and the corresponding error propagation. We found that wind speed percentage errors of 10% were propagated into the power output estimates, thereby yielding an error of 5%. The proposed error propagation complements the traditional power resource assessments. The wind power estimation error also allows us to estimate intervals for the power production leveled cost or the investment time return. The implementation of this method increases the reliability of techno-economic resource assessment studies.

Did accelerated depreciation result in lower generation efficiencies for wind plants in India: An empirical analysis

International Nuclear Information System (INIS)

Shrimali, Gireesh; Pusarla, Shreya; Trivedi, Saurabh

2017-01-01

India ranks fifth in wind energy installations in the world; with an installed wind capacity is 22 GW at the end of 2014. This has been made possible by a combination of federal financial incentives and state-level feed in tariffs. The federal policies are accelerated depreciation, which allows for higher depreciations in earlier years; and generation based incentive, which provides a premium for each unit of generation. Accelerated depreciation appears to be more effective from deployment and cost perspectives; whereas, generation based incentive is said to be more effective in incentivizing generation. In this paper, using multivariable linear regressions on a sample of approximately 40 wind plants, while controlling for wind regime and wind turbine technology, we investigate the incremental impact of generation based incentive compared to accelerated depreciation. We find that generation based incentive results in at least 3 percentage points higher plant load factors than accelerated depreciation. This indicates that, if higher generation is the goal of renewable policies, generation based incentive should be preferred to accelerated depreciation. This would be similar to the move from investment tax credit to production tax credit in the U.S. - Highlights: • We examine generation effectiveness of federal renewable policies in India. • We examine accelerated depreciation and generation based incentives. • We use a cross-sectional regression analysis on a sample of approx. 40 wind plants. • Generation based incentive results in 3 percentage points higher plant load factor.

Self-Powered Wind Sensor System for Detecting Wind Speed and Direction Based on a Triboelectric Nanogenerator.

Science.gov (United States)

Wang, Jiyu; Ding, Wenbo; Pan, Lun; Wu, Changsheng; Yu, Hua; Yang, Lijun; Liao, Ruijin; Wang, Zhong Lin

2018-04-24

The development of the Internet of Things has brought new challenges to the corresponding distributed sensor systems. Self-powered sensors that can perceive and respond to environmental stimuli without an external power supply are highly desirable. In this paper, a self-powered wind sensor system based on an anemometer triboelectric nanogenerator (a-TENG, free-standing mode) and a wind vane triboelectric nanogenerator (v-TENG, single-electrode mode) is proposed for simultaneously detecting wind speed and direction. A soft friction mode is adopted instead of a typical rigid friction for largely enhancing the output performance of the TENG. The design parameters including size, unit central angle, and applied materials are optimized to enhance sensitivity, resolution, and wide measurement scale. The optimized a-TENG could deliver an open-circuit voltage of 88 V and short-circuit current of 6.3 μA, corresponding to a maximum power output of 0.47 mW (wind speed of 6.0 m/s), which is capable of driving electronics for data transmission and storage. The current peak value of the a-TENG signal is used for analyzing wind speed for less energy consumption. Moreover, the output characteristics of a v-TENG are further explored, with six actual operation situations, and the v-TENG delivers fast response to the incoming wind and accurately outputs the wind direction data. As a wind sensor system, wind speed ranging from 2.7 to 8.0 m/s can be well detected (consistent with a commercial sensor) and eight regular directions can be monitored. Therefore, the fabricated wind sensor system has great potential in wireless environmental monitoring applications.

Wind power development in the United States: Effects of policies and electricity transmission congestion

Science.gov (United States)

Hitaj, Claudia

In this dissertation, I analyze the drivers of wind power development in the United States as well as the relationship between renewable power plant location and transmission congestion and emissions levels. I first examine the role of government renewable energy incentives and access to the electricity grid on investment in wind power plants across counties from 1998-2007. The results indicate that the federal production tax credit, state-level sales tax credit and production incentives play an important role in promoting wind power. In addition, higher wind power penetration levels can be achieved by bringing more parts of the electricity transmission grid under independent system operator regulation. I conclude that state and federal government policies play a significant role in wind power development both by providing financial support and by improving physical and procedural access to the electricity grid. Second, I examine the effect of renewable power plant location on electricity transmission congestion levels and system-wide emissions levels in a theoretical model and a simulation study. A new renewable plant takes the effect of congestion on its own output into account, but ignores the effect of its marginal contribution to congestion on output from existing plants, which results in curtailment of renewable power. Though pricing congestion removes the externality and reduces curtailment, I find that in the absence of a price on emissions, pricing congestion may in some cases actually increase system-wide emissions. The final part of my dissertation deals with an econometric issue that emerged from the empirical analysis of the drivers of wind power. I study the effect of the degree of censoring on random-effects Tobit estimates in finite sample with a particular focus on severe censoring, when the percentage of uncensored observations reaches 1 to 5 percent. The results show that the Tobit model performs well even at 5 percent uncensored observations

Wind Power Plant Voltage Stability Evaluation: Preprint

Energy Technology Data Exchange (ETDEWEB)

Muljadi, E.; Zhang, Y. C.

2014-09-01

Voltage stability refers to the ability of a power system to maintain steady voltages at all buses in the system after being subjected to a disturbance from a given initial operating condition. Voltage stability depends on a power system's ability to maintain and/or restore equilibrium between load demand and supply. Instability that may result occurs in the form of a progressive fall or rise of voltages of some buses. Possible outcomes of voltage instability are the loss of load in an area or tripped transmission lines and other elements by their protective systems, which may lead to cascading outages. The loss of synchronism of some generators may result from these outages or from operating conditions that violate a synchronous generator's field current limit, or in the case of variable speed wind turbine generator, the current limits of power switches. This paper investigates the impact of wind power plants on power system voltage stability by using synchrophasor measurements.

On the Use of Coupled Wind, Wave, and Current Fields in the Simulation of Loads on Bottom-Supported Offshore Wind Turbines during Hurricanes: March 2012 - September 2015

Energy Technology Data Exchange (ETDEWEB)

Kim, Eungsoo [Univ. of Texas, Austin, TX (United States); Manuel, Lance [Univ. of Texas, Austin, TX (United States); Curcic, Milan [Univ. of Miami, Coral Gables, FL (United States); Chen, Shuyi S. [Univ. of Miami, Coral Gables, FL (United States); Phillips, Caleb [National Renewable Energy Lab. (NREL), Golden, CO (United States); Veers, Paul [National Renewable Energy Lab. (NREL), Golden, CO (United States)

2016-06-01

In the United States, potential offshore wind plant sites have been identified along the Atlantic seaboard and in the Gulf of Mexico. It is imperative that we define external conditions associated with hurricanes and severe winter storms and consider load cases for which wind turbines may need to be designed. We selected two hurricanes, Ike (2008) and Sandy (2012), and investigated the effect these tropical storms would have on bottom-supported offshore wind turbines that were hypothetically in or close to their path as they made landfall. For realistic turbine loads assessment, it is important that the coupled influences of the changing wind, wave, and current fields are simulated throughout the evolution of the hurricanes. We employed a coupled model--specifically, the University of Miami Coupled Model (UMCM)--that integrates atmospheric, wave, and ocean components to produce needed wind, wave, and current data. The wind data are used to generate appropriate vertical wind profiles and full wind velocity fields including turbulence; the current field over the water column is obtained by interpolated discrete output current data; and short-crested irregular second-order waves are simulated using output directional wave spectra from the coupled model. We studied two monopile-supported offshore wind turbines sited in 20 meters of water in the Gulf of Mexico to estimate loads during Hurricane Ike, and a jacket space-frame platform-supported offshore wind turbine sited in 50 meters of water in the mid-Atlantic region to estimate loads during Hurricane Sandy. In this report we discuss in detail how the simulated hurricane wind, wave, and current output data are used in turbine loads studies. In addition, important characteristics of the external conditions are studied, including the relative importance of swell versus wind seas, aerodynamic versus hydrodynamic forces, current velocity effects, yaw control options for the turbine, hydrodynamic drag versus inertia forces

Documentation, User Support, and Verification of Wind Turbine and Plant Models

Energy Technology Data Exchange (ETDEWEB)

Robert Zavadil; Vadim Zheglov; Yuriy Kazachkov; Bo Gong; Juan Sanchez; Jun Li

2012-09-18

As part of the Utility Wind Energy Integration Group (UWIG) and EnerNex's Wind Turbine Modeling Project, EnerNex has received ARRA (federal stimulus) funding through the Department of Energy (DOE) to further the progress of wind turbine and wind plant models. Despite the large existing and planned wind generation deployment, industry-standard models for wind generation have not been formally adopted. Models commonly provided for interconnection studies are not adequate for use in general transmission planning studies, where public, non-proprietary, documented and validated models are needed. NERC MOD (North American Electric Reliability Corporation) reliability standards require that power flow and dynamics models be provided, in accordance with regional requirements and procedures. The goal of this project is to accelerate the appropriate use of generic wind turbine models for transmission network analysis by: (1) Defining proposed enhancements to the generic wind turbine model structures that would allow representation of more advanced; (2) Comparative testing of the generic models against more detailed (and sometimes proprietary) versions developed by turbine vendors; (3) Developing recommended parameters for the generic models to best mimic the performance of specific commercial wind turbines; (4) Documenting results of the comparative simulations in an application guide for users; (5) Conducting technology transfer activities in regional workshops for dissemination of knowledge and information gained, and to engage electric power and wind industry personnel in the project while underway; (6) Designing of a "living" homepage to establish an online resource for transmission planners.

Modeling energy production of solar thermal systems and wind turbines for installation at corn ethanol plants

Science.gov (United States)

Ehrke, Elizabeth

Nearly every aspect of human existence relies on energy in some way. Most of this energy is currently derived from fossil fuel resources. Increasing energy demands coupled with environmental and national security concerns have facilitated the move towards renewable energy sources. Biofuels like corn ethanol are one of the ways the U.S. has significantly reduced petroleum consumption. However, the large energy requirement of corn ethanol limits the net benefit of the fuel. Using renewable energy sources to produce ethanol can greatly improve its economic and environmental benefits. The main purpose of this study was to model the useful energy received from a solar thermal array and a wind turbine at various locations to determine the feasibility of applying these technologies at ethanol plants around the country. The model calculates thermal energy received from a solar collector array and electricity generated by a wind turbine utilizing various input data to characterize the equipment. Project cost and energy rate inputs are used to evaluate the profitability of the solar array or wind turbine. The current state of the wind and solar markets were examined to give an accurate representation of the economics of each industry. Eighteen ethanol plant locations were evaluated for the viability of a solar thermal array and/or wind turbine. All ethanol plant locations have long payback periods for solar thermal arrays, but high natural gas prices significantly reduce this timeframe. Government incentives will be necessary for the economic feasibility of solar thermal arrays. Wind turbines can be very profitable for ethanol plants in the Midwest due to large wind resources. The profitability of wind power is sensitive to regional energy prices. However, government incentives for wind power do not significantly change the economic feasibility of a wind turbine. This model can be used by current or future ethanol facilities to investigate or begin the planning process for a

Sensitivity Analysis of Wind Plant Performance to Key Turbine Design Parameters: A Systems Engineering Approach; Preprint

Energy Technology Data Exchange (ETDEWEB)

Dykes, K.; Ning, A.; King, R.; Graf, P.; Scott, G.; Veers, P.

2014-02-01

This paper introduces the development of a new software framework for research, design, and development of wind energy systems which is meant to 1) represent a full wind plant including all physical and nonphysical assets and associated costs up to the point of grid interconnection, 2) allow use of interchangeable models of varying fidelity for different aspects of the system, and 3) support system level multidisciplinary analyses and optimizations. This paper describes the design of the overall software capability and applies it to a global sensitivity analysis of wind turbine and plant performance and cost. The analysis was performed using three different model configurations involving different levels of fidelity, which illustrate how increasing fidelity can preserve important system interactions that build up to overall system performance and cost. Analyses were performed for a reference wind plant based on the National Renewable Energy Laboratory's 5-MW reference turbine at a mid-Atlantic offshore location within the United States.

Wind resource estimation and siting of wind turbines

DEFF Research Database (Denmark)

Lundtang Petersen, Erik; Mortensen, N.G.; Landberg, L.

1994-01-01

Detailed knowledge of the characteristics of the natural wind is necessary for the design, planning and operational aspect of wind energy systems. Here, we shall only be concerned with those meteorological aspects of wind energy planning that are termed wind resource estimation. The estimation...... of the wind resource ranges from the overall estimation of the mean energy content of the wind over a large area - called regional assessment - to the prediction of the average yearly energy production of a specific wind turbine at a specific location - called siting. A regional assessment will most often...... lead to a so-called wind atlas. A precise prediction of the wind speed at a given site is essential because for aerodynamic reasons the power output of a wind turbine is proportional to the third power of the wind speed, hence even small errors in prediction of wind speed may result in large deviations...

A Continuing Education Short Course and Engineering Curriculum to Accelerate Workforce Development in Wind Power Plant Design, Construction, and Operations

Energy Technology Data Exchange (ETDEWEB)

Tinjum, James [Univ. of Wisconsin, Madison, WI (United States)

2012-11-29

Significant advances in wind turbine technology and wind turbine power plant capabilities are appearing in the U.S. Sites that only 10 years ago might have been overlooked are being considered for build out. However, the development of a skilled workforce in the engineering fields and construction trades lags the potential market, especially if the industry is expected to site, design, construct, and operate sufficient wind power plant sites to meet the potential for 20% wind energy by 2030. A select few firms have penetrated the engineer-procure-construction (EPC) market of wind power plant construction. Competition and know-how in this market is vital to achieve cost-effective, design-construct solutions. The industry must produce or retrain engineers, contractors, and technicians to meet ambitious goals. Currently, few universities offer undergraduate or graduate classes that teach the basics in designing, building, and maintaining wind power plants that are safe, efficient, and productive.

Type IV Wind Turbine Model

DEFF Research Database (Denmark)

Hansen, Anca Daniela; Margaris, Ioannis D.

. In the project, this wind turbine model will be further incorporated in a wind power plant model together with the implementation in the wind power control level of the new control functionalities (inertial response, synchronising power and power system damping). For this purpose an aggregate wind power plant......This document is created as part of the EaseWind project. The goal of this project is to develop and investigate new control features for primary response provided by wind power plants. New control features as inertial response, synchronising power and power system damping are of interest to EaseWind...... project to be incorporated in the wind power plant level. This document describes the Type 4 wind turbine simulation model, implemented in the EaseWind project. The implemented wind turbine model is one of the initial necessary steps toward integrating new control services in the wind power plant level...

Wind-Climate Estimation Based on Mesoscale and Microscale Modeling: Statistical-Dynamical Downscaling for Wind Energy Applications

DEFF Research Database (Denmark)

Badger, Jake; Frank, Helmut; Hahmann, Andrea N.

2014-01-01

This paper demonstrates that a statistical dynamical method can be used to accurately estimate the wind climate at a wind farm site. In particular, postprocessing of mesoscale model output allows an efficient calculation of the local wind climate required for wind resource estimation at a wind...

Concept for inland wind power plants and wind parks - an example from North-Rhine Westphalia; Rahmenkonzept fuer Windkraftanlagen und -parks im Binnenland - ein Beipiel aus Nordrhein-Westfalen

Energy Technology Data Exchange (ETDEWEB)

Kleinschmidt, V. [UVP-Forschungsstelle, Fachgebiet Landschaftsoekologie und Landschaftsplanung, Fachbereich Raumplanung, Dortmund Univ. (Germany); Schauerte-Lueke, N. [UVP-Forschungsstelle, Fachgebiet Landschaftsoekologie und Landschaftsplanung, Fachbereich Raumplanung, Dortmund Univ. (Germany); Bergmann, R. [PRO TERRA TEAM Dienstleistungs- und Forschungsgesellschaft fuer Umwelttechnologien GmbH und Co. KG, Dortmund (Germany)

1994-12-31

Because of the increasing number of wind energy plants, environmental protection gets into a conflict of aims. On the one hand the change of the `Stromeinspeisungsgesetz` (law arranging the insertion of privately produced electricity into the public system) and the improved support for wind energy plants is to appreciate for the reasons of a reduction of CO{sub 2} and other harmful substances. But on the other hand wind energy plants have negative environmental effects onto the sites they are built on, as for example disturbances of the birds their breeding nest and feeding habitat, injury or death following collision with a blade or tower or simply disturbances of the landscape view. To avoid possible conflicts and increase the acceptance of wind energy plants, for the district of Soest a concept on a strategic level was developed, in which sites were determined as optimal, restrictional or excluding the construction of wind energy plants. This concept may not only help to avoid conflicts but may also play an active part in the promotion of wind energy plants by defining the sites suitable for wind energy plants and making them public. All in all the procedure of approval was simplified and therefore accelerated with the invention of this concept. (orig.) [Deutsch] Durch die zunehmende Anzahl von Windkraftanlagen geraet der Umweltschutz in einen Zielkonflikt. Einerseits ist die Aenderung des Stromeinspeisungsgesetzes und die verbesserte Foerderung fuer Windkraftanlagen aus Gruenden der CO{sub 2} und Schadstoffemissionseinsparungen sehr zu begruessen. Andererseits haben die Windkraftanlagen direkt an den Aufstellungsorten negative Auswirkungen auf die Umwelt, wie zum Beispiel Stoerung der Voegel in Nahrungs- und Bruthabitaten, Vogelschlag oder Beeintraechtigung des Landschaftsbildes. Um moegliche Konflikte weitgehend zu vermeiden und die Akzeptanz fuer Windkraftanlagen zu erhoehen, wurde fuer den Kreis Soest ein Rahmenkonzept erarbeitet, in dem Gunst-, Restriktions

Energy Storage Opportunities and Capabilities in a Type 3 Wind Turbine Generator: Preprint

Energy Technology Data Exchange (ETDEWEB)

Muljadi, Eduard; Gevorgian, Vahan; Hoke, Andy

2016-09-01

Wind power plants and other renewable power plants with power electronic interfaces are capable of delivering frequency response (both governor and/or inertial response) to the grid by a control action; thus, the reduction of available online inertia as conventional power plants are retired can be compensated by designing renewable power plant controls to include frequency response. The source of energy to be delivered as inertial response is determined by the type of generation and control strategy chosen. The cost of energy storage is expected to drop over time, and global research activities on energy storage are very active, funded both by the private industry and governments. Different industry sectors (e.g., transportation, energy) are the major drivers of the recent storage research and development. This work investigates the opportunities and capabilities of deploying energy storage in renewable power plants. In particular, we focus on wind power plants with doubly-fed induction generators, or Type 3 wind turbine generator (WTGs). We find that the total output power of a system with Type 3 WTGs with energy storage can deliver a power boost during inertial response that is up to 45% higher than one without energy storage without affecting the torque limit, thus enabling an effective delivery of ancillary services to the grid.

Optimal wind energy penetration in power systems: An approach based on spatial distribution of wind speed

International Nuclear Information System (INIS)

Zolfaghari, Saeed; Riahy, Gholam H.; Abedi, Mehrdad; Golshannavaz, Sajjad

2016-01-01

Highlights: • Chronological wind speeds at distinct locations of the wind farm are not the same. • Spatial distribution of wind speed affects wind farm’s output power expectation. • Neglecting wind speed’s spatial doubt leads to mistake in wind energy penetration. • Scenario-based method can be used for effective wind capacity penetration level. - Abstract: Contributing in power system expansions, the present study establishes an efficient scheme for optimal integration of wind energy resources. The proposed approach highly concerns the spatial distribution of wind speed at different points of a wind farm. In mathematical statements, a suitable probability distribution function (PDF) is well-designed for representing such uncertainties. In such conditions, it is likely to have dissimilar output powers for individual and identical wind turbines. Thus, the overall aggregated PDF of a wind farm remarkably influences the critical parameters including the expected power and energy, capacity factor, and the reliability metrics such as loss of load expectation (LOLE) and expected energy not supplied (EENS). Furthermore, the proposed approach is deployed for optimal allocation of wind energy in bulk power systems. Hence, two typical test systems are numerically analyzed to interrogate the performance of the proposed approach. The conducted survey discloses an over/underestimation of harvestable wind energy in the case of overlooking spatial distributions. Thus, inaccurate amounts of wind farm’s capacity factor, output power, energy and reliability indices might be estimated. Meanwhile, the number of wind turbines may be misjudged to be installed. However, the proposed approach yields in a fair judgment regarding the overall performance of the wind farm. Consequently, a reliable penetration level of wind energy to the power system is assured. Extra discussions are provided to deeply assess the promising merits of the founded approach.

Development of large scale wind energy conservation system. Development of control techniques for assembly-type wind power generating systems; Ogata furyoku hatsuden system no kaihatsu. Shugogata furyoku hatsuden system no seigyo gijutsu no kaihatsu

Energy Technology Data Exchange (ETDEWEB)

Takita, M [New Energy and Industrial Technology Development Organization, Tokyo (Japan)

1994-12-01

Described herein are the results of the FY1994 research program for development of control techniques for assembly-type wind power generating systems. The study on optimum system configuration produces 50 to 100kW wind power units for screening small-size wind power plant types, and, at the same time, surveys performance of commercial units and experiences of 9 makers capable of producing the above units. As a result, 3 MICON`s units (output: 100kW, active YAW control, monopole tower, maximum wind speed: 60m/s) are selected. The study on optimum operational techniques integrates 2 medium-size power units into a power line, showing a service factor of 30.2% on the annual average, monthly varying in a range from 11.8 to 45.0%. These units, installed in Miyako Island, were attacked by 3 typhoons of wind velocity of 25m/s or higher in 1994, and the only damage recorded is that of the anemoscope/anemometer. It is found that No.1 unit is located at a better geographical point than the No.2 unit, to produce a higher output. 3 figs., 3 tabs.

Maximum wind power plant generation by reducing the wake effect

International Nuclear Information System (INIS)

De-Prada-Gil, Mikel; Alías, César Guillén; Gomis-Bellmunt, Oriol; Sumper, Andreas

2015-01-01

Highlights: • To analyze the benefit of applying a new control strategy to maximise energy yield. • To operate some wind turbines at non-optimum points for reducing wake effects. • Single, partial and multiple wakes for any wind direction are taken into account. • Thrust coefficient is computed according to Blade Element Momentum (BEM) theory. - Abstract: This paper analyses, from a steady state point of view, the potential benefit of a Wind Power Plant (WPP) control strategy whose main objective is to maximise its total energy yield over its lifetime by taking into consideration that the wake effect within the WPP varies depending on the operation of each wind turbine. Unlike the conventional approach in which each wind turbine operation is optimised individually to maximise its own energy capture, the proposed control strategy aims to optimise the whole system by operating some wind turbines at sub-optimum points, so that the wake effect within the WPP is reduced and therefore the total power generation is maximised. The methodology used to assess the performance of both control approaches is presented and applied to two particular study cases. It contains a comprehensive wake model considering single, partial and multiple wake effects among turbines. The study also takes into account the Blade Element Momentum (BEM) theory to accurately compute both power and thrust coefficient of each wind turbine. The results suggest a good potential of the proposed concept, since an increase in the annual energy captured by the WPP from 1.86% up to 6.24% may be achieved (depending on the wind rose at the WPP location) by operating some specific wind turbines slightly away from their optimum point and reducing thus the wake effect

Wind energy economics

International Nuclear Information System (INIS)

Milborrow, D.J.

1995-01-01

The economics of wind energy have improved rapidly in the past few years, with improvements in machine performance and increases in size both contributing to reduce costs. These trends are examined and future costs assessed. As bank loan periods for wind projects are shorter than for thermal plant, the effect on the price of wind energy is discussed. It is argued that wind energy has a higher value than that of centralised plant, since it is fed into the low voltage distribution network and it follows that the price of wind energy is converging with its value. The paper also includes a brief review of the capacity credit of wind plant and an assessment of the cost penalties which are incurred due to the need to hold extra plant on part load. These penalties are shown to be small. (author)

Observability of wind power

International Nuclear Information System (INIS)

Gonot, J.P.; Fraisse, J.L.

2009-01-01

The total installed capacity of wind power grows from a few hundred MW at the beginning of 2005 to 3400 MW at the end of 2008. With such a trend, a total capacity of 7000 MW could be reached by 2010. The natural variability of wind power and the difficulty of its predictability require a change in the traditional way of managing supply/demand balance, day-ahead margins and the control of electrical flows. As a consequence, RTE operators should be informed quickly and reliably of the real time output power of wind farms and of its evolvement some hours or days ahead to ensure the reliability of the French electrical power system. French specificities are that wind farms are largely spread over the territory, that 95 % of wind farms have an output power below 10 MW and that they are connected to the distribution network. In this context, new tools were necessary to acquire as soon as possible data concerning wind power. In two years long, RTE set up an observatory of wind production 'IPES system' enable to get an access to the technical characteristics of the whole wind farms, to observe in real time 75 % of the wind generation and to implement a forecast model related to wind generation. (authors)

Wind energy power plants (wind farms) review and analysis

Energy Technology Data Exchange (ETDEWEB)

Newbold, K B; McKeary, M [McMaster Univ., Hamilton, ON (Canada). McMaster Inst. of Environment and Health

2010-07-01

Global wind power capacity has increased by an average cumulative rate of over 30 percent over the past 10 years. Although wind energy emits no air pollutants and facilities can often share spaces with other activities, public opposition to wind power development is an ongoing cause of concern. Development at the local level in Ontario has been met with fierce opposition on the basis of health concerns, aesthetic values, potential environmental impacts, and economic risks. This report was prepared for the Town of Wasaga Beach, and examined some of the controversy surrounding wind power developments through a review of evidence found in the scientific literature. The impacts of wind power developments related to noise, shadow flicker, avian mortality, bats, and real estate values were evaluated. The study included details of interviews conducted with individuals from Ontario localities where wind farms were located. 77 refs., 1 tab., 1 fig., 2 appendices.

Indirect solar wind geothermal: Alternative energy sources 4, volume 4

Science.gov (United States)

Veziroglu, T. N.

The utilities are obliged to provide electricity in a reliable and cost effective manner. Some unique problems posed by large scale wind turbines as an electricity source have to be considered. A value model is presented which is based upon the fuel displacement capability and the capacity displacement capability of wind turbines. The amount of fossil fuels which is saved by wind turbines depends on the forecasted wind power output, the actual power output fluctuations of the wind turbines and on system operation. The highly controversial capacity credit of wind turbines is discussed under the aspect of system reliability. It is shown that calculations of the capacity credit should be based upon detailed investigations with regard to the time dependence of the hourly wind power output.

Coordinated Voltage Control Scheme for VSC-HVDC Connected Wind Power Plants

DEFF Research Database (Denmark)

Guo, Yifei; Gao, Houlei; Wu, Qiuwei

2017-01-01

This paper proposes a coordinated voltage control scheme based on model predictive control (MPC) for voltage source converter‐based high voltage direct current (VSC‐HVDC) connected wind power plants (WPPs). In the proposed scheme, voltage regulation capabilities of VSC and WTGs are fully utilized...... and optimally coordinated. Two control modes, namely operation optimization mode and corrective mode, are designed to coordinate voltage control and economic operation of the system. In the first mode, the control objective includes the bus voltages, power losses and dynamic Var reserves of wind turbine...

Ancillary Frequency Control of Direct Drive Full-Scale Converter Based Wind Power Plants

DEFF Research Database (Denmark)

Hu, Weihao; Su, Chi; Fang, Jiakun

2013-01-01

This paper presents a simulation model of a wind power plant based on a MW-level variable speed wind turbine with a full-scale back-to-back power converter developed in the simulation tool of DIgSILENT Power Factory. Three different kinds of ancillary frequency control strategies, namely inertia...... control strategies are effective means for providing ancillary frequency control of variable speed wind turbines with full-scale back-to-back power converters....... emulation, primary frequency control and secondary frequency control, are proposed in order to improve the frequency stability of power systems. The modified IEEE 39-bus test system with a large-scale wind power penetration is chosen as the studied power system. Simulation results show that the proposed...

Wind power integration : From individual wind turbine to wind park as a power plant

NARCIS (Netherlands)

Zhou, Y.

2009-01-01

As power capacities of single wind turbine, single wind park and total wind power installation are continuously increasing, the wind power begins to challenge the safety operation of the power system. This thesis focuses on the grid integration aspects such as the dynamic behaviours of wind power

Evaluation of wind farm efficiency and wind turbine wakes at the Nysted offshore wind farm

DEFF Research Database (Denmark)

Barthelmie, Rebecca Jane; Jensen, L.E.

2010-01-01

Here, we quantify relationships between wind farm efficiency and wind speed, direction, turbulence and atmospheric stability using power output from the large offshore wind farm at Nysted in Denmark. Wake losses are, as expected, most strongly related to wind speed variations through the turbine...... thrust coefficient; with direction, atmospheric stability and turbulence as important second order effects. While the wind farm efficiency is highly dependent on the distribution of wind speeds and wind direction, it is shown that the impact of turbine spacing on wake losses and turbine efficiency can...... be quantified, albeit with relatively large uncertainty due to stochastic effects in the data. There is evidence of the ‘deep array effect’ in that wake losses in the centre of the wind farm are under-estimated by the wind farm model WAsP, although overall efficiency of the wind farm is well predicted due...

Smart — STATCOM control strategy implementation in wind power plants

DEFF Research Database (Denmark)

Sintamarean, Nicolae Christian; Cantarellas, Antoni Mir; Miranda, H.

2012-01-01

High penetration of wind energy into the grid may introduce stability and power quality problems due to the fluctuating nature of the wind and the increasing complexity of the power system. By implementing advanced functionalities in power converters, it is possible to improve the performance...... of the wind farm and also to provide grid support, as it is required by the grid codes. One of the main compliance difficulties that can be found in such power plants are related to reactive power compensation and to keep the harmonics content between the allowed limits, even if the power of the WPP...... converters is increasing. This paper deals with an advanced control strategy design of a three-level converter performing STATCOM and Active Filter functionalities. The proposed system is called Smart-STATCOM since it has the capability of self-controlling reactive power and harmonic voltages at the same...

NWTC Researchers Field-Test Advanced Control Turbine Systems to Increase Performance, Decrease Structural Loading of Wind Turbines and Plants

Energy Technology Data Exchange (ETDEWEB)

2015-08-01

Researchers at the National Renewable Energy Laboratory's (NREL's) National Wind Technology Center (NWTC) are studying component controls, including new advanced actuators and sensors, for both conventional turbines as well as wind plants. This research will help develop innovative control strategies that reduce aerodynamic structural loads and improve performance. Structural loads can cause damage that increase maintenance costs and shorten the life of a turbine or wind plant.

Stochastic Prediction of Wind Generating Resources Using the Enhanced Ensemble Model for Jeju Island’s Wind Farms in South Korea

Directory of Open Access Journals (Sweden)

Deockho Kim

2017-05-01

Full Text Available Due to the intermittency of wind power generation, it is very hard to manage its system operation and planning. In order to incorporate higher wind power penetrations into power systems that maintain secure and economic power system operation, an accurate and efficient estimation of wind power outputs is needed. In this paper, we propose the stochastic prediction of wind generating resources using an enhanced ensemble model for Jeju Island’s wind farms in South Korea. When selecting the potential sites of wind farms, wind speed data at points of interest are not always available. We apply the Kriging method, which is one of spatial interpolation, to estimate wind speed at potential sites. We also consider a wind profile power law to correct wind speed along the turbine height and terrain characteristics. After that, we used estimated wind speed data to calculate wind power output and select the best wind farm sites using a Weibull distribution. Probability density function (PDF or cumulative density function (CDF is used to estimate the probability of wind speed. The wind speed data is classified along the manufacturer’s power curve data. Therefore, the probability of wind speed is also given in accordance with classified values. The average wind power output is estimated in the form of a confidence interval. The empirical data of meteorological towers from Jeju Island in Korea is used to interpolate the wind speed data spatially at potential sites. Finally, we propose the best wind farm site among the four potential wind farm sites.

Wind rotor power station BONI-ShHV

International Nuclear Information System (INIS)

Bolotov, A.V.

1999-01-01

Wind rotor power station (WRPS) BONI-ShHV has following advantages : the increase of installation stability by rise of wind velocity and rotation speed of rotor due to gyroscopic effect; the absence noise and vibration; the safety for birds and animals; ability of compact installation and creation of series of wind power dams with higher capacity; the simplicity and fast assembling and putting into operation. The price of 1 k W of installing capacity is lower about 2.5-3 times compare to usual WRPS due to simple kinematic scheme. WRPS has high specific output of electrical energy due to use of low and long existing wind velocity and due to short storms, giving greater power. It has ability to be replayed when average annual wind velocity is above 5.5 m/s in comparison with propeller WRPS, which are never repaying. WRPS BONI-ShHV are made on the plants of Republic of Kazakhstan, and tested in wind velocity range up 45 m/s, have experience of 3 years of operation, showing their reliability and effectiveness. The repayment period of individual WRPS BONI-0.5/6 ShHV is from 10 month to 1 year depending on average annual velocity

Optimizing transmission from distant wind farms

International Nuclear Information System (INIS)

Pattanariyankool, Sompop; Lave, Lester B.

2010-01-01

We explore the optimal size of the transmission line from distant wind farms, modeling the tradeoff between transmission cost and benefit from delivered wind power. We also examine the benefit of connecting a second wind farm, requiring additional transmission, in order to increase output smoothness. Since a wind farm has a low capacity factor, the transmission line would not be heavily loaded, on average; depending on the time profile of generation, for wind farms with capacity factor of 29-34%, profit is maximized for a line that is about 3/4 of the nameplate capacity of the wind farm. Although wind generation is inexpensive at a good site, transmitting wind power over 1600 km (about the distance from Wyoming to Los Angeles) doubles the delivered cost of power. As the price for power rises, the optimal capacity of transmission increases. Connecting wind farms lowers delivered cost when the wind farms are close, despite the high correlation of output over time. Imposing a penalty for failing to deliver minimum contracted supply leads to connecting more distant wind farms.

Improving Wind Farm Dispatchability Using Model Predictive Control for Optimal Operation of Grid-Scale Energy Storage

Directory of Open Access Journals (Sweden)

Douglas Halamay

2014-09-01

Full Text Available This paper demonstrates the use of model-based predictive control for energy storage systems to improve the dispatchability of wind power plants. Large-scale wind penetration increases the variability of power flow on the grid, thus increasing reserve requirements. Large energy storage systems collocated with wind farms can improve dispatchability of the wind plant by storing energy during generation over-the-schedule and sourcing energy during generation under-the-schedule, essentially providing on-site reserves. Model predictive control (MPC provides a natural framework for this application. By utilizing an accurate energy storage system model, control actions can be planned in the context of system power and state-of-charge limitations. MPC also enables the inclusion of predicted wind farm performance over a near-term horizon that allows control actions to be planned in anticipation of fast changes, such as wind ramps. This paper demonstrates that model-based predictive control can improve system performance compared with a standard non-predictive, non-model-based control approach. It is also demonstrated that secondary objectives, such as reducing the rate of change of the wind plant output (i.e., ramps, can be considered and successfully implemented within the MPC framework. Specifically, it is shown that scheduling error can be reduced by 81%, reserve requirements can be improved by up to 37%, and the number of ramp events can be reduced by 74%.

Detailed Equivalent VSC-HVDC Modelling for Time Domain Harmonic Stability Studies in Wind Power Plants

DEFF Research Database (Denmark)

Glasdam, Jakob Bærholm; Bak, Claus Leth; Kocewiak, Lukasz Hubert

2018-01-01

system with 201 voltage levels, without loss of accuracy compared to conventional modelling of the converter. Harmonic stability is a core concern for both existing and future offshore wind power plants (OWPPs). A harmonic stability study will be undertaken with focus on the number of wind turbine...

On maintenance management of wind and nuclear power plants

International Nuclear Information System (INIS)

Nilsson, Julia

2009-11-01

Electrical production in Sweden today is mainly from nuclear and hydro power. However, there is large increase in renewable energy like wind power and the installed new capacity goals are large. Several electrical production sources are important for the sustainability of the energy system. Maintenance is an approach for keeping a system sustainable. The importance of structured maintenance for reliable electrical production systems triggers the development of qualitative and quantitative maintenance management methods. Examples of these methods are Reliability-Centered Maintenance (RCM) which is a structured qualitative approach that focuses on reliability when planning maintenance, and Reliability Centered Asset Management (RCAM) which is a development of RCM into a quantitative approach with the aim to relate preventive maintenance to total maintenance cost and system reliability. This thesis presents models, as applications of RCAM, based on the methods of Life Cycle Cost (LCC) and mathematical optimization, applied to wind and nuclear power plants. Both deterministic and stochastic approaches have been used and the proposed models are based on the Total Cost model, which summarizes costs for maintenance and production loss, and the Aircraft model, which is an opportunistic maintenance optimization model. Opportunistic maintenance is preventive maintenance performed at opportunities. The wind power applications in this study show on different ways to cover costs of condition monitoring systems (CMS) and further on economic benefits of these when uncertainties of times to failure are included in the model. The nuclear power applications show on that the optimization model is dependent on the discount rate and that a high discount rate gives more motivation for opportunistic replacements. When put into a stochastic framework and compared to other maintenance strategies it is shown that an extended opportunistic maintenance optimization model has a good overall

Frequency Activated Fast Power Reserve for Wind Power Plant Delivered from Stored Kinetic Energy in the Wind Turbine Inertia

DEFF Research Database (Denmark)

Knüppel, Thyge; Thuring, P.; Kumar, S

2011-01-01

is proposed that delivers a short-term power reserve from the kinetic energy in the wind turbine (WT) inertia, while considering the inherent characteristics of a wind power plant. The aim is to contribute with a fast power reserve to stabilize the frequency drop during large and sudden production deficits......With increased penetration of converter interfaced generation, synchronous generators may start to be displaced to keep the overall power balance. As a consequence the resulting inertia in the system may decrease and make the power system more exposed to frequency excursions. Here, a control...

Modelling of offshore wind turbine wakes with the wind farm program FLaP

DEFF Research Database (Denmark)

Lange, B.; Waldl, H.P.; Guerrero, A.G.

2003-01-01

The wind farm layout program FLaP estimates the wind speed at any point in a wind farm and the power output of the turbines. The ambient flow conditions and the properties of the turbines and the farm are used as input. The core of the program is an axisymmetric wake model describing the wake...

Increase net plant output through selective operation of the heat-rejection system

International Nuclear Information System (INIS)

Ostrowski, E.T.; Queenan, P.T.

1987-01-01

Depending on unit load and ambient meteorological conditions, a net increase of 800 to 5500 kW in plant output is possible for many generating units through optimized operation of the major motor-driven equipment in the heat-rejection system - the circulating water pumps and mechanical-draft cooling tower fans. This can be realised when the resulting decrease in auxiliary-power demand is greater than the decrease in gross electric generation caused by operating fewer pumps and/or fans. No capital expenditures are incurred and only operating procedures are involved so that the performance gains are achieved at no cost. The paper considers the application of this technique to nuclear power plants, pump optimization and the superimposition of fan and cooling tower performance curves

Enhanced Dynamic Voltage Stability Support by VSC-HVDC for Offshore Wind Applications using Trajectory Sensitivity Analysis

DEFF Research Database (Denmark)

Liu, Hongzhi; Chen, Zhe; Liu, Leo

2013-01-01

The integration of large-scale wind power plants changes the structure, configuration and operation of conventional power systems and brings challenges to the security and stability of power systems. Dynamic voltage stability of power systems with high wind penetration is one of the critical issues....... In this paper, VSC-HVDC transmission system is used to integrate a large-scale wind power plant into the onshore power grid. For different voltage support strategies of VSC-HVDC, a trajectory sensitivity analysisbased approach is proposed to find the minimum onshore VSC capacity with which the VSC-HVDC can...... provide enough support for the improvement of system voltage stability after a disturbance. Sensitivities of reactive power output of VSC to its capacity increase are calculated instead of the sensitivities of bus voltage magnitude towards the reactive power injection variation of VSC. Simulation results...

Variability in large-scale wind power generation: Variability in large-scale wind power generation

Energy Technology Data Exchange (ETDEWEB)

Kiviluoma, Juha [VTT Technical Research Centre of Finland, Espoo Finland; Holttinen, Hannele [VTT Technical Research Centre of Finland, Espoo Finland; Weir, David [Energy Department, Norwegian Water Resources and Energy Directorate, Oslo Norway; Scharff, Richard [KTH Royal Institute of Technology, Electric Power Systems, Stockholm Sweden; Söder, Lennart [Royal Institute of Technology, Electric Power Systems, Stockholm Sweden; Menemenlis, Nickie [Institut de recherche Hydro-Québec, Montreal Canada; Cutululis, Nicolaos A. [DTU, Wind Energy, Roskilde Denmark; Danti Lopez, Irene [Electricity Research Centre, University College Dublin, Dublin Ireland; Lannoye, Eamonn [Electric Power Research Institute, Palo Alto California USA; Estanqueiro, Ana [LNEG, Laboratorio Nacional de Energia e Geologia, UESEO, Lisbon Spain; Gomez-Lazaro, Emilio [Renewable Energy Research Institute and DIEEAC/EDII-AB, Castilla-La Mancha University, Albacete Spain; Zhang, Qin [State Grid Corporation of China, Beijing China; Bai, Jianhua [State Grid Energy Research Institute Beijing, Beijing China; Wan, Yih-Huei [National Renewable Energy Laboratory, Transmission and Grid Integration Group, Golden Colorado USA; Milligan, Michael [National Renewable Energy Laboratory, Transmission and Grid Integration Group, Golden Colorado USA

2015-10-25

The paper demonstrates the characteristics of wind power variability and net load variability in multiple power systems based on real data from multiple years. Demonstrated characteristics include probability distribution for different ramp durations, seasonal and diurnal variability and low net load events. The comparison shows regions with low variability (Sweden, Spain and Germany), medium variability (Portugal, Ireland, Finland and Denmark) and regions with higher variability (Quebec, Bonneville Power Administration and Electric Reliability Council of Texas in North America; Gansu, Jilin and Liaoning in China; and Norway and offshore wind power in Denmark). For regions with low variability, the maximum 1 h wind ramps are below 10% of nominal capacity, and for regions with high variability, they may be close to 30%. Wind power variability is mainly explained by the extent of geographical spread, but also higher capacity factor causes higher variability. It was also shown how wind power ramps are autocorrelated and dependent on the operating output level. When wind power was concentrated in smaller area, there were outliers with high changes in wind output, which were not present in large areas with well-dispersed wind power.

Reactive power interconnection requirements for PV and wind plants : recommendations to NERC.

Energy Technology Data Exchange (ETDEWEB)

McDowell, Jason (General Electric, Schenectady, NY); Walling, Reigh (General Electric, Schenectady, NY); Peter, William (SunPower, Richmond, CA); Von Engeln, Edi (NV Energy, Reno, NV); Seymour, Eric (AEI, Fort Collins, CO); Nelson, Robert (Siemens Wind Turbines, Orlando, FL); Casey, Leo (Satcon, Boston, MA); Ellis, Abraham; Barker, Chris. (SunPower, Richmond, CA)

2012-02-01

Voltage on the North American bulk system is normally regulated by synchronous generators, which typically are provided with voltage schedules by transmission system operators. In the past, variable generation plants were considered very small relative to conventional generating units, and were characteristically either induction generator (wind) or line-commutated inverters (photovoltaic) that have no inherent voltage regulation capability. However, the growing level of penetration of non-traditional renewable generation - especially wind and solar - has led to the need for renewable generation to contribute more significantly to power system voltage control and reactive power capacity. Modern wind-turbine generators, and increasingly PV inverters as well, have considerable dynamic reactive power capability, which can be further enhanced with other reactive support equipment at the plant level to meet interconnection requirements. This report contains a set of recommendations to the North-America Electricity Reliability Corporation (NERC) as part of Task 1-3 (interconnection requirements) of the Integration of Variable Generation Task Force (IVGTF) work plan. The report discusses reactive capability of different generator technologies, reviews existing reactive power standards, and provides specific recommendations to improve existing interconnection standards.

Multi input-output fuzzy logic smart controller for a residential hybrid solar-wind-storage energy system

International Nuclear Information System (INIS)

Derrouazin, A.; Aillerie, M.; Mekkakia-Maaza, N.; Charles, J.-P.

2017-01-01

Highlights: • We present a fuzzy smart controller for hybrid renewable and conventional energy system. • The rules are based on human intelligence and implemented in the smart controller. • Efficient tracking capability of the proposed controller is proofed in this paper by an example. • Excess produced renewable energy is converted to hydrogen for household use . • Considerable electric grid energy saving is highlighted in the proposed controller system. - Abstract: This study concerns the conception and development of an efficient multi input-output fuzzy logic smart controller, to manage the energy flux of a sustainable hybrid power system, based on renewable power sources, integrating solar panels and a wind turbine associated with storage, applied to a typical residential habitat. In the suggested topology, the energy surplus is redirected to an electrolysis system to produce hydrogen suitable for household utilities. To assume a constant access to electricity in case of consumption peak, connection to the grid is also considered as an exceptional rescue resource. The objective of the presented controller is to exploit instantaneously the produced renewable electric energy and insure savings of electric grid energy. The proposed multi input-output fuzzy logic smart controller has been achieved and verified, outcome switches command signals are discussed and the renewable energy system integration ratio is highlighted.

Control and operation of wind turbine converters during faults in an offshore wind power plant grid with VSC-HVDC connection

DEFF Research Database (Denmark)

Chaudhary, Sanjay; Teodorescu, Remus; Rodriguez, Pedro

2011-01-01

Voltage source converter (VSC) based high voltage dc (HVDC) transmission is an attractive technique for large offshore wind power plants, especially when long cable transmission is required for connection to the onshore grid. New multi-MW wind turbines are likely to be equipped with full scale...... converters to meet the stringent grid code requirements. In such a scenario, the offshore grid is terminated to the power electronic converters on all the ends. This paper presents a control scheme for the synchronization and control of the grid side converters (GSC) of the wind turbine generators (WTG......). Current limit control enables the GSC to sustain the fault currents during short circuits in the offshore wind collector system grid. However, power transmission is affected, and the fault has to be isolated. It can be resynchronized after the fault has been cleared and the breaker reclosed. Healthy WTG...

Control of Full-Scale Converter based Wind Power Plants for damping of low frequency system oscillations

DEFF Research Database (Denmark)

Adamczyk, Andrzej Grzegorz; Teodorescu, Remus; Rodriguez, Pedro

2011-01-01

Damping of low frequency power oscillations is one of essential aspects of maintaining power system stability. In literature can be found publications on damping capability of Doubly Fed Induction Generator based wind turbines. This paper extends discussion on Wind Power Plant damping capability...

Variability of the Wind Turbine Power Curve

Directory of Open Access Journals (Sweden)

Mahesh M. Bandi

2016-09-01

Full Text Available Wind turbine power curves are calibrated by turbine manufacturers under requirements stipulated by the International Electrotechnical Commission to provide a functional mapping between the mean wind speed v ¯ and the mean turbine power output P ¯ . Wind plant operators employ these power curves to estimate or forecast wind power generation under given wind conditions. However, it is general knowledge that wide variability exists in these mean calibration values. We first analyse how the standard deviation in wind speed σ v affects the mean P ¯ and the standard deviation σ P of wind power. We find that the magnitude of wind power fluctuations scales as the square of the mean wind speed. Using data from three planetary locations, we find that the wind speed standard deviation σ v systematically varies with mean wind speed v ¯ , and in some instances, follows a scaling of the form σ v = C × v ¯ α ; C being a constant and α a fractional power. We show that, when applicable, this scaling form provides a minimal parameter description of the power curve in terms of v ¯ alone. Wind data from different locations establishes that (in instances when this scaling exists the exponent α varies with location, owing to the influence of local environmental conditions on wind speed variability. Since manufacturer-calibrated power curves cannot account for variability influenced by local conditions, this variability translates to forecast uncertainty in power generation. We close with a proposal for operators to perform post-installation recalibration of their turbine power curves to account for the influence of local environmental factors on wind speed variability in order to reduce the uncertainty of wind power forecasts. Understanding the relationship between wind’s speed and its variability is likely to lead to lower costs for the integration of wind power into the electric grid.

An optimization approach for wind turbine commitment and dispatch in a wind park

Energy Technology Data Exchange (ETDEWEB)

Moyano, Carlos F. [School of Engineering Systems, Faculty of Built Environment and Engineering, Queensland University of Technology, GPO Box 2434, Brisbane, QLD 4001 (Australia); Pecas Lopes, Joao A. [Instituto de Engenharia de Sistemas e Computadores do Porto (Portugal); Faculdade de Engenharia da Universidade do Porto, Campus da FEUP, Rua Dr. Roberto Frias, 378 4200-465 Porto (Portugal)

2009-01-15

This paper describes an operational optimization strategy to be adopted at the wind park control level, that enables defining the commitment of wind turbines and their active and reactive power outputs following requests from Wind Park Dispatch Centers, assuming that individual wind turbines short-term wind speed forecasts are known and are expressed as power availability. This operational strategy was also developed with a concern on the minimization of the connection/disconnection changes of the individual wind generators, for a given time horizon. When identifying the active/reactive dispatching policies, wind generators loading capabilities are also taken in account. This optimization tool is especially suited to manage large wind parks. (author)

Harmonic Stability and Resonance Analysis in Large PMSG-Based Wind Power Plants

DEFF Research Database (Denmark)

Ebrahimzadeh, Esmaeil; Blaabjerg, Frede; Wang, Xiongfei

2018-01-01

Compared to the conventional power systems, large Wind Power Plants (WPPs) present a more challenging system where the interactions between the passive elements and the wideband control systems of power converters may result in harmonic instability and new resonance frequencies. Most of researches...... system and the resonance frequencies are identified based on the element amplitudes of the MIMO matrix. An active damping controller is used to set the poles of the WPP in a desired location in order to mitigate the harmonic instability problems. Multiple case studies are provided to depict that Wind...

Output-Feedback Model Predictive Control of a Pasteurization Pilot Plant based on an LPV model

Science.gov (United States)

Karimi Pour, Fatemeh; Ocampo-Martinez, Carlos; Puig, Vicenç

2017-01-01

This paper presents a model predictive control (MPC) of a pasteurization pilot plant based on an LPV model. Since not all the states are measured, an observer is also designed, which allows implementing an output-feedback MPC scheme. However, the model of the plant is not completely observable when augmented with the disturbance models. In order to solve this problem, the following strategies are used: (i) the whole system is decoupled into two subsystems, (ii) an inner state-feedback controller is implemented into the MPC control scheme. A real-time example based on the pasteurization pilot plant is simulated as a case study for testing the behavior of the approaches.

Residue-based evaluation of the use of wind power plants with full converter wind turbines for power oscillation damping control

DEFF Research Database (Denmark)

Morato, Josep; Knüppel, Thyge; Østergaard, Jacob

2013-01-01

As wind power plants (WPPs) gradually replace the power production of the conventional generators, many aspects of the power system may be affected, in which the small signal stability is included. Additional control may be needed for wind turbine generators (WTGs) to participate in the power...... oscillation damping. The feasibility of implementing this control needs to be assessed. This paper studies how the damping contribution of a WPP is affected by different operating conditions and its dependence to selected feedback signals. The WPP model used includes individual WTGs to study how internal...

Electric power from offshore wind via synoptic-scale interconnection.

Science.gov (United States)

Kempton, Willett; Pimenta, Felipe M; Veron, Dana E; Colle, Brian A

2010-04-20

World wind power resources are abundant, but their utilization could be limited because wind fluctuates rather than providing steady power. We hypothesize that wind power output could be stabilized if wind generators were located in a meteorologically designed configuration and electrically connected. Based on 5 yr of wind data from 11 meteorological stations, distributed over a 2,500 km extent along the U.S. East Coast, power output for each hour at each site is calculated. Each individual wind power generation site exhibits the expected power ups and downs. But when we simulate a power line connecting them, called here the Atlantic Transmission Grid, the output from the entire set of generators rarely reaches either low or full power, and power changes slowly. Notably, during the 5-yr study period, the amount of power shifted up and down but never stopped. This finding is explained by examining in detail the high and low output periods, using reanalysis data to show the weather phenomena responsible for steady production and for the occasional periods of low power. We conclude with suggested institutions appropriate to create and manage the power system analyzed here.

Electric power from offshore wind via synoptic-scale interconnection

Science.gov (United States)

Kempton, Willett; Pimenta, Felipe M.; Veron, Dana E.; Colle, Brian A.

2010-01-01

World wind power resources are abundant, but their utilization could be limited because wind fluctuates rather than providing steady power. We hypothesize that wind power output could be stabilized if wind generators were located in a meteorologically designed configuration and electrically connected. Based on 5 yr of wind data from 11 meteorological stations, distributed over a 2,500 km extent along the U.S. East Coast, power output for each hour at each site is calculated. Each individual wind power generation site exhibits the expected power ups and downs. But when we simulate a power line connecting them, called here the Atlantic Transmission Grid, the output from the entire set of generators rarely reaches either low or full power, and power changes slowly. Notably, during the 5-yr study period, the amount of power shifted up and down but never stopped. This finding is explained by examining in detail the high and low output periods, using reanalysis data to show the weather phenomena responsible for steady production and for the occasional periods of low power. We conclude with suggested institutions appropriate to create and manage the power system analyzed here. PMID:20368464

Planning your first wind power project. A primer for utilities: Everything you need to know to bring your first wind power plant on-line

International Nuclear Information System (INIS)

Conover, K.; Davis, E.

1994-12-01

This primer has been prepared to help utility personnel become familiar with some or the details relative to wind power technology and project development. It is written as a series of relatively independent chapters to address specific topics or phases of wind power evaluation and development as they might occur within a utility. The topics include: wind prospecting and the first pass analysis, resource validation, project feasibility, resource planning and evaluation, resource acquisition, project development, equipment selection, project design and construction, and plant operation and maintenance

Power oscillation damping capabilities of wind power plant with full converter wind turbines considering its distributed and modular characteristics

DEFF Research Database (Denmark)

Knüppel, Thyge; Nielsen, Jørgen N.; Jensen, Kim H.

2013-01-01

Wind power plants (WPP) are for power system stability studies often represented with aggregated models where several wind turbines (WT) are aggregated into a single up-scaled model. The advantage is a reduction in the model complexity and the computational time, and for a number of study types...... aggregation is investigated and it is shown that the level of WPP aggregation only has limited impact on the resulting modal damping. The study is based on a non-linear, dynamic model of the 3.6 MW Siemens Wind Power WT....... the accuracy of the results has been found acceptable. A large WPP is, however, both modular and distributed over a large geographical area, and feasibility of aggregating the WTs, thus, have to be reassessed when new applications are introduced for WPPs. Here, the power oscillation damping capabilities...

Design and Application of Cables and Overhead Lines in Wind Power Plants

Energy Technology Data Exchange (ETDEWEB)

Behnke, M. R. [IEEE PES Wind Plant Collector System Design Working Group; Bellei, T.A. [IEEE PES Wind Plant Collector System Design Working Group; Bloethe, W.G. [IEEE PES Wind Plant Collector System Design Working Group; Bradt, M. [IEEE PES Wind Plant Collector System Design Working Group; Brooks, C. [IEEE PES Wind Plant Collector System Design Working Group; Camm, E H [IEEE PES Wind Plant Collector System Design Working Group; Dilling, W. [IEEE PES Wind Plant Collector System Design Working Group; Goltz, B. [IEEE PES Wind Plant Collector System Design Working Group; Hermanson, J. [IEEE PES Wind Plant Collector System Design Working Group; Li, J. [IEEE PES Wind Plant Collector System Design Working Group; Loy, P. [IEEE PES Wind Plant Collector System Design Working Group; McLean, K. [IEEE PES Wind Plant Collector System Design Working Group; Niemira, J. [IEEE PES Wind Plant Collector System Design Working Group; Nuckles, K. [IEEE PES Wind Plant Collector System Design Working Group; Patino, J. [IEEE PES Wind Plant Collector System Design Working Group; Reza, M [IEEE PES Wind Plant Collector System Design Working Group; Richardson, B. [IEEE PES Wind Plant Collector System Design Working Group; Samaan, N. [IEEE PES Wind Plant Collector System Design Working Group; Schoene, Jens [IEEE PES Wind Plant Collector System Design Working Group; Smith, Travis M [ORNL; Snyder, Isabelle B [ORNL; Starke, Michael R [ORNL; Tesch, M. [IEEE PES Wind Plant Collector System Design Working Group; Walling, R. [IEEE PES Wind Plant Collector System Design Working Group; Zahalka, G. [IEEE PES Wind Plant Collector System Design Working Group

2010-01-01

This paper presents a summary of the most impor- tant considerations for wind power plant collection system un- derground and overhead cable designs. Various considerations, including conductor selection, soil thermal properties, installa- tion methods, splicing, concentric grounding, and NESC/NEC requirements are discussed.

Wind power forecast error smoothing within a wind farm

International Nuclear Information System (INIS)

Saleck, Nadja; Bremen, Lueder von

2007-01-01

Smoothing of wind power forecast errors is well-known for large areas. Comparable effects within a wind farm are investigated in this paper. A Neural Network was taken to predict the power output of a wind farm in north-western Germany comprising 17 turbines. A comparison was done between an algorithm that fits mean wind and mean power data of the wind farm and a second algorithm that fits wind and power data individually for each turbine. The evaluation of root mean square errors (RMSE) shows that relative small smoothing effects occur. However, it can be shown for this wind farm that individual calculations have the advantage that only a few turbines are needed to give better results than the use of mean data. Furthermore different results occurred if predicted wind speeds are directly fitted to observed wind power or if predicted wind speeds are first fitted to observed wind speeds and then applied to a power curve. The first approach gives slightly better RMSE values, the bias improves considerably

Transmission cost minimization strategies for wind-electric generating facilities

Energy Technology Data Exchange (ETDEWEB)

Gonzalez, R. [Northern States Power Company, Minneapolis, MN (United States)

1997-12-31

Integrating wind-electric generation facilities into existing power systems presents opportunities not encountered in conventional energy projects. Minimizing outlet cost requires probabilistic value-based analyses appropriately reflecting the wind facility`s operational characteristics. The wind resource`s intermittent nature permits relaxation of deterministic criteria addressing outlet configuration and capacity required relative to facility rating. Equivalent capacity ratings of wind generation facilities being a fraction of installed nameplate rating, outlet design studies contingency analyses can concentrate on this fractional value. Further, given its non-dispatchable, low capacity factor nature, a lower level of redundancy in outlet facilities is appropriate considering the trifling contribution to output unreliability. Further cost reduction opportunities arise from {open_quotes}wind speed/generator power output{close_quotes} and {open_quotes}wind speed/overhead conductor rating{close_quotes} functions` correlation. Proper analysis permits the correlation`s exploitation to safely increase line ratings. Lastly, poor correlation between output and utility load may permit use of smaller conductors, whose higher (mostly off-peak) losses are economically justifiable.

Economic optimisation of a wind power plant for isolated locations

International Nuclear Information System (INIS)

Fortunato, B.; Mummolo, G.; Cavallera, G.

1997-01-01

This paper presents a model of a wind power plant for isolated locations composed of a vertical axis wind turbine connected to a self-excited induction generator operating at constant voltage and frequency; a back-up diesel generator and a battery system are moreover included in the system. Constant voltage and frequency are obtained only by controlling the generator appropriately. The control system is supposed to be optimised so that the system operates at the highest efficiency. In order to improve the total efficiency even further, a gear-box to vary the gear transmission ratio between the turbine and the generator has been considered. A ''Monte Carlo'' type simulation has been used to analyse the operation of that system over a one year period. The model is based on a probability density function of the wind speed derived by statistical data concerning a given location and on the probabilistic curve of the load required by an isolated location. The cost per kW h for different dimensions of the main components has been evaluated and the optimum configuration has been identified. (author)

Wind Power Fluctuation Smoothing Controller Based on Risk Assessment of Grid Frequency Deviation in an Isolated System

DEFF Research Database (Denmark)

Lin, Jin; Sun, Yuanzhang; Song, Yonghua

2013-01-01

a smoothing controller to suppress the power fluctuation from doubly-fed induction generator (DFIG)-based wind farm. This controller consists of threemain functionality components: risk assessmentmodel, wind turbine rotor speed optimizer, and rotor speed upper limiter. In order to avoid unnecessary energy...... curve with reduced output so that a trade-off between fluctuation smoothing and energy loss is achieved. Subsequently, the controller limits the maximum rotor speed to shift down the power curve of wind power plant based on the optimal wind turbine rotor speed. Therefore, the power fluctuation......Wind power fluctuation raises the security concern of grid frequency deviation, especially for an isolated power system. Thus, better control methodology needs to be developed to smooth the fluctuation without excessive spillage. Based on an actual industrial power system, this paper proposes...

Study on wind turbine for Yamagata wind energy institute. Comparison of the actual and estimate values for electric power; Yamagata furyoku hatsudensho no fusha ni tsuite. Hatsudenryo yosoku to jissekichi no hikaku

Energy Technology Data Exchange (ETDEWEB)

Nagai, H [Nihon University, Tokyo (Japan); Kojima, T [Yamagata Wind Energy Institute, Yamagata (Japan)

1996-10-27

For two 400kW wind turbines erected in Jan. 1996 of Yamagata Wind Energy Institute, their estimated power output was compared with actual output for 7 months. AMeDAS data in 1985-94 were totaled every month to use as basic data. The altitude and surface roughness model necessary for WAsP analysis recommended by NEDO`s wind condition close inspection manual were prepared using 1/25,000 maps and aerial photographs. The obstacle model for estimating wind conditions at height of the wind turbine was prepared using the data obtained by field survey. Mean wind velocity and latent energy were determined by statistical analysis of wind velocity occurrence relative frequencies and Weibull distribution parameters. The power output of 717,700kWh was obtained for 7 months, which is equivalent to 88.5% of the estimated output of 810,730kWh for the same period. It was clarified from obtained characteristic wind conditions at the site that the wind power generation is promising at the site not only in winter but also in summer. Although the test period was too short, this method was effective as analytical method of output estimation in the planning stage of wind turbines. 3 refs., 8 figs., 4 tabs.

Profiling the regional wind power fluctuation in China

International Nuclear Information System (INIS)

Yu Dayang; Liang Jun; Han Xueshan; Zhao Jianguo

2011-01-01

As China starts to build 6 10-GW wind zones in 5 provinces by 2020, accommodating the wind electricity generated from these large wind zones will be a great challenge for the regional grids. Inadequate wind observing data hinders profiling the wind power fluctuations at the regional grid level. This paper proposed a method to assess the seasonal and diurnal wind power patterns based on the wind speed data from the NASA GEOS-5 DAS system, which provides data to the study of climate processes including the long-term estimates of meteorological quantities. The wind power fluctuations for the 6 largest wind zones in China are presented with both the capacity factor and the megawatt wind power output. The measured hourly wind output in a regional grid is compared to the calculating result to test the analyzing model. To investigate the offsetting effect of dispersed wind farms over large regions, the regional correlations of hourly wind power fluctuations are calculated. The result illustrates the different offsetting effects of minute and hourly fluctuations.

Using High-Fidelity Computational Fluid Dynamics to Help Design a Wind Turbine Wake Measurement Experiment

International Nuclear Information System (INIS)

Churchfield, M; Wang, Q; Scholbrock, A; Herges, T; Mikkelsen, T; Sjöholm, M

2016-01-01

We describe the process of using large-eddy simulations of wind turbine wake flow to help design a wake measurement campaign. The main goal of the experiment is to measure wakes and wake deflection that result from intentional yaw misalignment under a variety of atmospheric conditions at the Scaled Wind Farm Technology facility operated by Sandia National Laboratories in Lubbock, Texas. Prior simulation studies have shown that wake deflection may be used for wind-plant control that maximizes plant power output. In this study, simulations are performed to characterize wake deflection and general behavior before the experiment is performed to ensure better upfront planning. Beyond characterizing the expected wake behavior, we also use the large-eddy simulation to test a virtual version of the lidar we plan to use to measure the wake and better understand our lidar scan strategy options. This work is an excellent example of a “simulation-in-the-loop” measurement campaign. (paper)

Method for Prediction of the Power Output from Photovoltaic Power Plant under Actual Operating Conditions

Science.gov (United States)

Obukhov, S. G.; Plotnikov, I. A.; Surzhikova, O. A.; Savkin, K. D.

2017-04-01

Solar photovoltaic technology is one of the most rapidly growing renewable sources of electricity that has practical application in various fields of human activity due to its high availability, huge potential and environmental compatibility. The original simulation model of the photovoltaic power plant has been developed to simulate and investigate the plant operating modes under actual operating conditions. The proposed model considers the impact of the external climatic factors on the solar panel energy characteristics that improves accuracy in the power output prediction. The data obtained through the photovoltaic power plant operation simulation enable a well-reasoned choice of the required capacity for storage devices and determination of the rational algorithms to control the energy complex.

Operational Strategies for a Portfolio of Wind Farms and CHP Plants in a Two-Price Balancing Market

DEFF Research Database (Denmark)

Hellmers, Anna; Zugno, Marco; Skajaa, Anders

2015-01-01

In this paper we explore the portfolio effect of a system consisting of a Combined Heat and Power (CHP) plant and a wind farm. The goal is to increase the overall profit of the portfolio by reducing imbalances, and consequently their implicit penalty in a two-price balancing market for electricity......-horizon fashion, so that forecasts for heat demand, wind power production and market prices are updated at each iteration. We conclude that the portfolio strategy is the most profitable due to the two-price structure of the balancing market. This encourages producers to handle their imbalances outside the market........ We investigate two different operational strategies, which differ in whether the CHP plant and the wind farm are operated jointly or independently, and we evaluate their economic performance on a real case study based on a CHP-wind system located in the western part of Denmark. We present...

Design and Tuning Methodology of Active Power Controller in Wind Power Plants

DEFF Research Database (Denmark)

Ionita, Claudiu; Raducu, Alin George; Iov, Florin

2017-01-01

This paper presents a method to design and tune the main controller of a Wind Power Plant (WPP), with focus on the active power and frequency control. The controller requirements are based on the Danish grid codes. The controller functionality is successfully verified using the model and the layout...... of an actual WPP rated at 160 MW, that consists of 80 wind turbines. Two reference dispatch strategies are investigated, equal and proportional. The proportional dispatch is preferred due to better tracking accuracy and robustness. The work described in this article is meant to help WPP developers...

FENCH-analysis of electricity generation greenhouse gas emissions from solar and wind power in Germany

International Nuclear Information System (INIS)

Hartmann, D.

1997-01-01

The assessment of energy supply systems with regard to the influence on climate change requires not only the quantification of direct emissions caused by the operation of a power plant. It also has to take into account indirect emissions resulting from e.g. construction and dismounting of the power plant. Processes like manufacturing the materials for building the plant, the transportation of components and the construction and maintenance of the power plant are included. A tool to determine and assess the energy and mass flows is the Life Cycle Analysis (LCA) which allows the assessment of environmental impacts related to a product or service. In this paper a FENCH (Full Energy Chain)-analysis based on a LCA of electricity production from wind and solar power plants under operation conditions typical for application its Germany is presented. The FENCH-analysis is based on two methods, Process Chain Analysis (PCA) and Input-Output-Analysis (IOA) which are illustrated by the example of an electricity generation from a wind power plant. The calculated results are shown for the cumulated (indirect and direct) Greenhouse-Gas (GHG)-emissions for an electricity production from wind and solar power plants. A comparison of the results to the electricity production from a coal fired power plant is performed. At last a comparison of 1 kWh electricity from renewable energy to 1 kWh from fossil energy carrier has to be done, because the benefits of 1 kWh electricity from various types of power plants are different. Electricity from wind energy depends on the meteorological conditions while electricity from a fossil fired power plant is able to follow the power requirements of the consumers nearly all the time. By considering the comparison of the different benefit provided the GHG-Emissions are presented. (author)

Optimization of the Energy Output of Osmotic Power Plants

Directory of Open Access Journals (Sweden)

Florian Dinger

2013-01-01

Full Text Available On the way to a completely renewable energy supply, additional alternatives to hydroelectric, wind, and solar power have to be investigated. Osmotic power is such an alternative with a theoretical global annual potential of up to 14400 TWh (70% of the global electricity consumption of 2008 per year. It utilizes the phenomenon that upon the mixing of fresh water and oceanic salt water (e.g., at a river mouth, around 2.88 MJ of energy per 1 m3 of fresh water is released. Here, we describe a new approach to derive operational parameter settings for osmotic power plants using a pressure exchanger for optimal performance, either with respect to maximum generated power or maximum extracted energy. Up to now, only power optimization is discussed in the literature, but when considering the fresh water supply as a limiting factor, the energy optimization appears as the challenging task.

A Reliability Based Model for Wind Turbine Selection

Directory of Open Access Journals (Sweden)

A.K. Rajeevan

2013-06-01

Full Text Available A wind turbine generator output at a specific site depends on many factors, particularly cut- in, rated and cut-out wind speed parameters. Hence power output varies from turbine to turbine. The objective of this paper is to develop a mathematical relationship between reliability and wind power generation. The analytical computation of monthly wind power is obtained from weibull statistical model using cubic mean cube root of wind speed. Reliability calculation is based on failure probability analysis. There are many different types of wind turbinescommercially available in the market. From reliability point of view, to get optimum reliability in power generation, it is desirable to select a wind turbine generator which is best suited for a site. The mathematical relationship developed in this paper can be used for site-matching turbine selection in reliability point of view.

Socio-economic effects of a HYSOL CSP plant located in different countries: An input output analysis

NARCIS (Netherlands)

Corona, B.; López, A.; San Miguel, G.

2016-01-01

The aim of this paper is to estimate the socioeconomic effects associated with the production of electricity by a CSP plant with HYSOL configuration, using Input Output Analysis. These effects have been estimated in terms of production of Goods and Services (G&S), multiplier effect, value added,

Synthetic wind speed scenarios generation for probabilistic analysis of hybrid energy systems

International Nuclear Information System (INIS)

Chen, Jun; Rabiti, Cristian

2017-01-01

Hybrid energy systems consisting of multiple energy inputs and multiple energy outputs have been proposed to be an effective element to enable ever increasing penetration of clean energy. In order to better understand the dynamic and probabilistic behavior of hybrid energy systems, this paper proposes a model combining Fourier series and autoregressive moving average (ARMA) to characterize historical weather measurements and to generate synthetic weather (e.g., wind speed) data. In particular, Fourier series is used to characterize the seasonal trend in historical data, while ARMA is applied to capture the autocorrelation in residue time series (e.g., measurements with seasonal trends subtracted). The generated synthetic wind speed data is then utilized to perform probabilistic analysis of a particular hybrid energy system configuration, which consists of nuclear power plant, wind farm, battery storage, natural gas boiler, and chemical plant. Requirements on component ramping rate, economic and environmental impacts of hybrid energy systems, and the effects of deploying different sizes of batteries in smoothing renewable variability, are all investigated. - Highlights: • Computational model to synthesize artificial wind speed data with consistent characteristics with database. • Fourier series to capture seasonal trends in the database. • Monte Carlo simulation and probabilistic analysis of hybrid energy systems. • Investigation of the effect of battery in smoothing variability of wind power generation.

HVDC Connected Offshore Wind Power Plants: Review and Outlook of Current Research

DEFF Research Database (Denmark)

Glasdam, Jakob; Zeni, Lorenzo; Gryning, Mikkel

2013-01-01

This paper presents a state-of-the-art review on grid integration of large offshore wind power plants (OWPPs) using high voltage direct voltage (HVDC) for grid connection. The paper describes in detail selected challenges hereto and presents how DONG Energy Wind Power (DEWP) is addressing...... these challenges through three coordinated PhD projects in close collaboration with leading academia within the field. The overall goal of these projects is to acquire in-depth knowledge of relevant operating phenomena in the offshore OWPP grid, rich with power electronics devices (PEDs) such as the HVDC...... and the PED widely used in the wind turbine generators (WTGs). Challenges hereto include PED control system interaction (from a stability point of view), assessment of the quality of vendor supplied control systems and their robustness against e.g. short circuits and load rejection. Furthermore, the outcome...

Husum wind `97. Amiable and powerful. Proceedings; Husum Wind `97. Liebenswert und leistungsstark. Kongressband

Energy Technology Data Exchange (ETDEWEB)

NONE

1997-12-31

The Husum Fair and Congress on Wind Energy 97 wants to inform on and demonstrate the state of the art of wind energy and its potentials of development. This conference volume contains 21 papers in seven sections: Wind energy - society and environment; forum of the wind power plant manufacturers represented at the Husum Wind 97; foreign markets for wind power plants; development prospects for wind power; wind power in retrospective and relevant operating experience; panel discussion ``The amendment to the act on remuneration for power fed into the mains - wind power in the lull``; excursion to the test field WINDTEST, Kaiser-Wilhelm-Koog. (AKF)

A data mining approach: Analyzing wind speed and insolation period data in Turkey for installations of wind and solar power plants

International Nuclear Information System (INIS)

Colak, Ilhami; Sagiroglu, Seref; Demirtas, Mehmet; Yesilbudak, Mehmet

2013-01-01

Highlights: ► Wind speed and insolation period data were analyzed using a data mining approach. ► Most of the studies in the literature were based on Weibull and Rayleigh models. ► Nearest and farest neighbor algorithms were used with different distance metrics. ► Many inferences were achieved in efficient limits for wind and solar farm analyses. - Abstract: Wind and solar power plant installations have been recently increased rapidly with respect to the depletion of fossil-based fuels all over the world. Due to stochastic nature of meteorological conditions, wind and solar energies have a non-schedulable nature and they require several installation analyses to determine the location and the capacities of wind and solar power to be produced. This paper focuses on the similarity, feasibility and numerical analyses of 75 cities in Turkey based on the monthly average wind speed and insolation period data. The nearest and the farest neighbor algorithms are used as agglomerative hierarchical clustering methods with Euclidean, Manhattan and Minkowski distance metrics in the stage of making the similarity and feasibility analyses. The maximum cophenetic correlation coefficient is achieved by the nearest neighbor algorithm with the Minkowski distance metric in the similarity and feasibility analyses. On the other hand, graphical representations of the monthly average wind speed and insolation period data are utilized for making the numerical analysis. The highest annual average wind speed and insolation period are obtained as 3.88 m/s and 8.45 h/day, respectively. Overall, many inferences were achieved in acceptable and efficient limits for wind and solar energy.

Possibilities of Utilization the Risk – Based Techniques in the Field of Offshore Wind Power Plants

Directory of Open Access Journals (Sweden)

Przemysław Kacprzak

2014-09-01

Full Text Available In the article the risk-based concept that may be applicable to offshore wind power plants has been presented. The aim of the concept is to aid designers in the early design and retrofit phases of the project in case of lack or insufficient information in relevant international standards. Moreover the initial classification of components within main system parts of offshore wind power plant has been performed. Such classification is essential in order to apply risk-based concept. However further scientific researches need to be performed in that field to develop detailed concept useful for future practical applications.

Measures against the adverse impact of natural wind on air-cooled condensers in power plant

Institute of Scientific and Technical Information of China (English)

无

2010-01-01

The natural wind plays disadvantageous roles in the operation of air-cooled steam condensers in power plant.It is of use to take various measures against the adverse effect of wind for the performance improvement of air-cooled condensers.Based on representative 2×600 MW direct air-cooled power plant,three ways that can arrange and optimize the flow field of cooling air thus enhance the heat transfer of air-cooled condensers were proposed.The physical and mathematical models of air-cooled condensers with various flow leading measures were presented and the flow and temperature fields of cooling air were obtained by CFD simulation.The back pressures of turbine were calculated for different measures on the basis of the heat transfer model of air-cooled condensers.The results show that the performance of air-cooled condensers is improved thus the back pressure of turbine is lowered to some extent by taking measures against the adverse impact of natural wind.

Control of VSC-HVDC in offshore AC islands with wind power plants: Comparison of two alternatives

DEFF Research Database (Denmark)

Zeni, Lorenzo; Hesselbæk, Bo; Sørensen, Poul Ejnar

2015-01-01

The subject of this paper is the control of offshore AC collection and export networks behind a voltage source converter based high voltage direct current transmission system. The inertia-less nature of such grids makes the control of voltages and power flows potentially more flexible......, but at the same time more prone to instabilities. Focus in this paper is on a voltage source converter based high voltage direct current connected wind power plant. Two state-of-art controllers for the offshore high voltage direct current converter station are compared, both at no-load and when wind turbine...... converters are producing power and controlled with usual vector current control. Sensitivity analyses help identify critical factors influencing stability. The influence of lumping the wind power plant into one converter is assessed by comparison with the full model. The conclusions identify the preferred...

Valence of wind power, photovoltaic and peak-load power plants as a part of the entire electricity system

International Nuclear Information System (INIS)

Schüppel, A.

2014-01-01

The transition to a higher share of renewable energy sources in the electricity sector leads to a multitude of challenges for the current electricity system. Within this thesis, the development of wind power and photovoltaics generation capacities in Germany is analysed based on the evaluation of technical and economic criteria. In order to derive those criteria, different scenarios with a separated and combined increase of wind and photovoltaics capacity are simulated using the model ATLANTIS. The results are compared to a reference scenario without additional wind and PV capacities. Furthermore, the value and functionality of the energy only market based on economic methods, as well as the value of peak load power plants based on opportunity costs are determined. The results of this thesis show, that the current market system is able to gain an additional annual welfare of four to six billion Euro at the best. This result shows that the task of optimising the power plant dispatch is well fulfilled by the current market design. However, the effects, e.g. fuel costs, which may influence this margin. The value of wind power and photovoltaics within the overall electricity system can be derived from the effort which is necessary to integrate these generation technologies into the existing system, and the changes in total costs of electricity generation. Based on the evaluation of time dependencies (seasonality of energy yield from wind and PV) as well as the development of total generation costs, the conclusion can be drawn that wind power is the more suitable RES generation technology for Germany. However, when it comes to grid integration measures, PV shows better results due to a higher generation potential in Southern Germany, which leads to a higher degree of utilisation. Therefore, there is no need to transport electricity from Northern to Southern Germany as it is the case with wind power. A common expansion of wind power and photovoltaics even shows slight

Power Curve Estimation With Multivariate Environmental Factors for Inland and Offshore Wind Farms

KAUST Repository

Lee, Giwhyun

2015-04-22

In the wind industry, a power curve refers to the functional relationship between the power output generated by a wind turbine and the wind speed at the time of power generation. Power curves are used in practice for a number of important tasks including predicting wind power production and assessing a turbine’s energy production efficiency. Nevertheless, actual wind power data indicate that the power output is affected by more than just wind speed. Several other environmental factors, such as wind direction, air density, humidity, turbulence intensity, and wind shears, have potential impact. Yet, in industry practice, as well as in the literature, current power curve models primarily consider wind speed and, sometimes, wind speed and direction. We propose an additive multivariate kernel method that can include the aforementioned environmental factors as a new power curve model. Our model provides, conditional on a given environmental condition, both the point estimation and density estimation of power output. It is able to capture the nonlinear relationships between environmental factors and the wind power output, as well as the high-order interaction effects among some of the environmental factors. Using operational data associated with four turbines in an inland wind farm and two turbines in an offshore wind farm, we demonstrate the improvement achieved by our kernel method.

Wind power: Areva acquires a 51% stake in Multibrid

International Nuclear Information System (INIS)

2007-01-01

AREVA announced the acquisition of a 51% stake in Multibrid, a designer and manufacturer of multi-megawatt off-shore wind turbines based in Germany. With this acquisition, AREVA has entered into a joint venture with Prokon Nord, a German off-shore wind turbine and biomass plant developer and current owner of Multibrid. This transaction values Multibrid at euro 150 million. AREVA plans to rapidly further develop Multibrid's activities by giving the company access to its industrial resources, financial base and international commercial network. In return, Multibrid will provide AREVA with its leading-edge technology which, developed for 5 MW turbines, can achieve a very high output while reducing operating costs thanks to a simplified maintenance system. With this stake in Multibrid, AREVA aims to increase its presence on the offshore wind market that meets land settlement requirements and that should grow significantly in the years to come (from 300 MW in Europe today to an expected 1400 MW by 2011). As an exclusive supplier of Prokon Nord, Multibrid will participate in projects such as Borkum West (30 MW), the first offshore project in Germany, Borkum West 2 (400 MW), and Cote d'Albatre (105 MW), the first offshore wind farm project in France. The stake in Multibrid strengthens AREVA's strategic positioning on the CO 2 -free energy market, thanks to complementary solutions ranging from nuclear technologies to renewables. A number of recent achievements illustrate this strategy: - bio-energy (crucial energy supply in numerous rural areas): delivery of turnkey biomass power plants; ongoing construction of 10 plants in India, Thailand and Brazil; future development plans in fast-growing regions, such as Latin America; - wind power: Multibrid adds to the Group's stake in REpower and to its partnership with Suzlon for which AREVA is the number one supplier of transmission and distribution solutions for wind power; - hydrogen and fuel cells: design and manufacture of

Operating wind turbines in strong wind conditions by using feedforward-feedback control

International Nuclear Information System (INIS)

Feng, Ju; Sheng, Wen Zhong

2014-01-01

Due to the increasing penetration of wind energy into power systems, it becomes critical to reduce the impact of wind energy on the stability and reliability of the overall power system. In precedent works, Shen and his co-workers developed a re-designed operation schema to run wind turbines in strong wind conditions based on optimization method and standard PI feedback control, which can prevent the typical shutdowns of wind turbines when reaching the cut-out wind speed. In this paper, a new control strategy combing the standard PI feedback control with feedforward controls using the optimization results is investigated for the operation of variable-speed pitch-regulated wind turbines in strong wind conditions. It is shown that the developed control strategy is capable of smoothening the power output of wind turbine and avoiding its sudden showdown at high wind speeds without worsening the loads on rotor and blades

[Effects of planting system on soil and water conservation and crop output value in a sloping land of Southwest China].

Science.gov (United States)

Xiang, Da-Bing; Yong, Tai-Wen; Yang, Wen-Yu; Yu, Xiao-Bo; Guo, Kai

2010-06-01

A three-year experiment was conducted to study the effects of wheat/maize/soybean with total no-tillage and mulching (NTM), wheat/maize/soybean with part no-tillage and part mulching (PTM), wheat/maize/soybean with total tillage without mulching (TWM), and wheat/maize/ sweet potato with total tillage without mulching (TWMS) on the soil and water conservation, soil fertility, and crop output value in a sloping land of Southwest China. The average soil erosion amount and surface runoff of NTM were significantly lower than those of the other three planting systems, being 1189 kg x hm(-2) and 215 m3 x hm(-2), and 10.6% and 84.7% lower than those of TWMS, respectively. The soil organic matter, total N, available K and available N contents of NTM were increased by 15.7%, 18.2%, 55.2%, and 25.9%, respectively, being the highest among the test planting systems. PTM and TWM took the second place, and TWMS pattern had the least. NTM had the highest annual crop output value (18809 yuan x hm(-2)) and net income (12619 yuan x hm(-2)) in three years, being 2.2% -20.6% and 3.8% -32.9% higher than other three planting systems, respectively. In a word, the planting system wheat/maize/soybean was more beneficial to the water and soil conservation and the improvement of soil fertility and crop output value, compared with the traditional planting system wheat/maize/sweet potato.

System frequency support of permanent magnet synchronous generator-based wind power plant

Science.gov (United States)

Wu, Ziping

With ever-increasing penetration of wind power into modern electric grids all over the world, a trending replacement of conventional synchronous generators by large wind power plants will likely result in the poor overall frequency regulation performance. On the other hand, permanent magnet synchronous generator wind Turbine System (PMSG-WTG) with full power back to back converters tends to become one of the most promising wind turbine technologies thanks to various advantages. It possesses a significant amount of kinetic energy stored in the rotating mass of turbine blades, which can be utilized to enhance the total inertia of power system. Additionally, the deloaded operation and decoupled control of active and reactive power make it possible for PMSG-WTG to provide a fast frequency regulation through full-power converter. First of all, a comprehensive and in-depth survey is conducted to analyze the motivations for incorporating the inertial response and frequency regulation of VSWT into the system frequency regulation. Besides, control classifications, fundamental control concepts and advanced control schemes implemented for auxiliary frequency support of individual WT or wind power plant are elaborated along with a comparison of the potential frequency regulation capabilities of four major types of WTs. Secondly, a Controls Advanced Research Turbine2-Permanent Magnet Synchronous Generator wind turbine (CART2-PMSG) integrated model representing the typical configuration and operation characteristics of PMSG-WT is established in Matlab/Simulink,. Meanwhile, two different rotor-side converter control schemes, including rotor speed-based control and active power-based control, are integrated into this CART2-PMSG integrated model to perform Maximum Power Point Tracking (MPPT) operation over a wide range of wind speeds, respectively. Thirdly, a novel comprehensive frequency regulation (CFR) control scheme is developed and implemented into the CART2-PMSG model based

Calculating the sensitivity of wind turbine loads to wind inputs using response surfaces

DEFF Research Database (Denmark)

Rinker, Jennifer M.

2016-01-01

at a low computational cost. Sobol sensitivity indices (SIs) can then be calculated with relative ease using the calibrated response surface. The proposed methodology is demonstrated by calculating the total sensitivity of the maximum blade root bending moment of the WindPACT 5 MW reference model to four......This paper presents a methodology to calculate wind turbine load sensitivities to turbulence parameters through the use of response surfaces. A response surface is a high-dimensional polynomial surface that can be calibrated to any set of input/output data and then used to generate synthetic data...... turbulence input parameters: a reference mean wind speed, a reference turbulence intensity, the Kaimal length scale, and a novel parameter reflecting the nonstationarity present in the inflow turbulence. The input/output data used to calibrate the response surface were generated for a previous project...

Pre- and post-construction studies of conflicts between birds and wind turbines in coastal Norway (BirdWind)

Energy Technology Data Exchange (ETDEWEB)

Bevanger, K.; Berntsen, F.; Clausen, S.; Dahl, E.L.; Flagstad, Oe.; Follestad, A.; Halley, D.; Hanssen, F.; Hoel, P.L.; Johnsen, L.; Kvaloey, P.; May, R.; Nygaard, T.; Pedersen, H.C.; Reitan, O.; Steinheim, Y.; Vang, R.

2009-12-15

connection to the planned extension of the existing power plant on Hitra I; the Hitra II Wind-Power Plant. Since 2003, 50 nestlings of white-tailed eagle have been equipped with satellite transmitters. In 2009, eight WTE nestlings were tagged, six with solar-powered and two with battery-powered transmitters. One was tagged within the wind-power plant, the others in close vicinity of it. The solar-powered transmitters used in 2009 were programmed to give one position per hour during summer in order to have finer resolution of movements for risk-modeling purposes. During winter less frequent downloading is scheduled, due to low light and poor battery-charging. One of the tagged nestlings was found killed by a turbine October 7. We have continued to collect feathers from active nests and chicks also in 2009, as well as from eagles killed in collisions with wind turbines. DNA-analyses from bones of six eagles killed by electrocution on power-line pylons on Smoela will also be included. For increased efficiency in the laboratory, and to streamline the production of DNA-data, the use of an extraction robot has been implemented. All WTE nest sites on Smoela were surveyed during the summer. Territorial activity, identified by either moulted adult feathers, chicks in the nest or fresh nest material, was confirmed in 61 different territories on the main island and in the surrounding archipelago. In these territories 27 chicks from 21 different clutches were recorded. This is the second highest number of chicks recorded ever on Smoela, giving a re-productive output of 0.44 chicks/confirmed occupied territory. In order to investigate behavioural differences for the WTE related to the distance from the turbines, data on flight activity (moving flight, social behaviour and soaring) and flight height (below, in and above the rotor zone) were collected at 12 vantage points, 6 from inside the wind-power plant area and 6 from control areas close to the power-plant area. The results indicate

Effects of nearby surface features on wind speed at a nuclear plant meteorological station

International Nuclear Information System (INIS)

Nielsen, N.A.; Goodwin, R.J.; Pittman, D.E.

1984-01-01

There is a definite cause and effect relationship between the trees in the vicinity of the meteorological tower and the wind speed at the 10-meter level on the meteorological tower. For the affected directions, horizontal wind speed is significantly reduced below what it would be for that level if the trees were not present. This effect is only slightly less for the 10:1 exposure achieved with the 1977 tree clearing, which illustrates that meeting this commonly accepted distance to height ratio does not assure representativeness of 10-meter data collected at a nuclear plant site. The somewhat stronger effect for winds from the south through southwest directions may be partly attributable to the abrupt change in roughness and elevation encountered by air moving at an angle or directly across the reservoir, which is 3.5 to 5.0 kilometers wide at this site. This general reduction in wind speed values below what would be expected at the plant location will result in biased dispersion estimates. Calculated relative concentration values for releases treated as ground-level or building-wake releases would be larger than actual concentrations. While this would provide conservative concentration values, radioactive plume transport calculations would be nonconservative. The calculated, or predicted, transport rate would be slower than the actual transport rate. Such local biases affecting the spatial representativeness of airflow at 10 meters are a primary reason for TVA's decision to use 46-meter wind data for ground-level transport and diffusion modeling in its radiological emergency preparedness program

Wind turbine technology principles and design

CERN Document Server

Adaramola, Muyiwa

2014-01-01

IntroductionPart I: AerodynamicsWind Turbine Blade Design; Peter J. Schubel and Richard J. CrossleyA Shrouded Wind Turbine Generating High Output Power with Wind-Lens Technology; Yuji Ohya and Takashi KarasudaniEcomoulding of Composite Wind Turbine Blades Using Green Manufacturing RTM Process; Brahim AttafAerodynamic Shape Optimization of a Vertical-Axis Wind Turbine Using Differential Evolution; Travis J. Carrigan, Brian H. Dennis, Zhen X. Han, and Bo P. WangPart II: Generators and Gear Systems

High resolution wind measurements for offshore wind energy development

Science.gov (United States)

Nghiem, Son Van (Inventor); Neumann, Gregory (Inventor)

2013-01-01

A method, apparatus, system, article of manufacture, and computer readable storage medium provide the ability to measure wind. Data at a first resolution (i.e., low resolution data) is collected by a satellite scatterometer. Thin slices of the data are determined. A collocation of the data slices are determined at each grid cell center to obtain ensembles of collocated data slices. Each ensemble of collocated data slices is decomposed into a mean part and a fluctuating part. The data is reconstructed at a second resolution from the mean part and a residue of the fluctuating part. A wind measurement is determined from the data at the second resolution using a wind model function. A description of the wind measurement is output.

Determination of performance parameters of vertical axis wind turbines in wind tunnel

Directory of Open Access Journals (Sweden)

Nguyen Van Bang

2017-01-01

Full Text Available The paper deals with the determination of the performance parameters of a small vertical axis wind turbines (VAWT, which operate by the utilization of drag forces acting on the blades of the turbine. The performance was evaluated by investigating the electrical power output and torque moment of the wind machine. Measurements were performed on the full-scale model and the experimental data are assessed and compared to other types of wind turbines, with respect to its purpose.

Arrangement for matching a wind rotor to an electrical generator

Energy Technology Data Exchange (ETDEWEB)

Beusse, H

1978-04-06

The invention concerns an arrangement for matching a wind power machine to an electrical generator, which feeds a consumer network. According to the invention first generator using the shaft horsepower of the wind power machine feeds an electric water, which is coupled to a second generator, whose power is taken to the consumer network. The output signal of a computer which has the annemometer feeding into it controls the excitation of the motor at sufficient wind speed, so that the speed of rotation of the second generator is practically constant, and a spted regulator takes excess energy via a controlled rectifier (thyristor) to a shunt circuit of the motor, if the wind power exceeds the load taken from the output of the second generator. As an extension of the arrangement according to the invention it is proposed to arrange a Diesel engine in the shaft of the second generator, which can be controlled at constant speed by the control device, so that it takes over the missing output if the wind power is less than the load at the generator output. Apart from this, it is proposed that the loading of the wind rotor should be controlled by the control device so that it only comes in if the wind rotor has reached a stable working point after accelerating on no load.

Wind energy in electric power production. Preliminary study

Energy Technology Data Exchange (ETDEWEB)

Lento, R; Peltola, E

1984-01-15

The wind speed conditions in Finland have been studied with the aid of the existing statistics of the Finnish Meteorological Institute. With the aid of the statistics also estimates on the available wind energy were made. 800 wind power plants, 1.5 MW each, on the windiest west coast would produce about 2 TWh energy per year. Far more information on the temporal, geographical and vertical distribution of the wind speed than the present statistics include is needed when the available wind energy is estimated, when wind power plants are dimensioned optimally, and when suitable locations are chosen for them. The investment costs of a wind power plant increase when the height of the tower or the diameter of the rotor is increased, but the energy production increases, too. Thus, overdimensioning the wind power plant in view of energy needs or the wind conditions causes extra costs. The cost of energy produced by wind power can not yet compete with conventional energy, but the situation changes to the advantage of wind energy, if the real price of the plants decreases (among other things due to large series production and increasing experience), or if the real price of fuels rises. The inconvinience on the environment caused by the wind power plants is considered insignificant. The noise caused by the plant attenuates rapidly with distance. No harmful effects birds and other animals caused by the wind power plants have been observed in the studies made abroad. Parts of a plant getting loose during an accident, or ice forming on the blades are estimated to fly even from a large plant only a few hundred meters.