WorldWideScience

Sample records for wind turbine impact

  1. Potential health impact of wind turbines

    International Nuclear Information System (INIS)

    2010-05-01

    In response to public health concerns about wind turbines, a study was conducted to review the scientific evidence on the potential health effects of wind turbines. Several research questions were examined, including scientific evidence on the potential health impacts of wind turbines; the relationship between wind turbine noise and health; the relationship between low frequency sound, infrasound and health; assessment of exposure to wind turbines; wind turbine health and safety hazards and Ontario wind turbine setbacks; community consultation prior to wind farm construction and data gaps and research needs. The study showed that although some people living near wind turbines reported symptoms such as dizziness, headaches, and sleep disturbance, the scientific evidence available to date does not demonstrate a direct causal link between wind turbine noise and adverse health effects. The sound level from wind turbines at common residential setbacks is not sufficient to cause hearing impairment or other direct health effects, although some people may find it annoying. 41 refs., 1 appendix.

  2. Potential health impact of wind turbines

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2010-05-15

    In response to public health concerns about wind turbines, a study was conducted to review the scientific evidence on the potential health effects of wind turbines. Several research questions were examined, including scientific evidence on the potential health impacts of wind turbines; the relationship between wind turbine noise and health; the relationship between low frequency sound, infrasound and health; assessment of exposure to wind turbines; wind turbine health and safety hazards and Ontario wind turbine setbacks; community consultation prior to wind farm construction and data gaps and research needs. The study showed that although some people living near wind turbines reported symptoms such as dizziness, headaches, and sleep disturbance, the scientific evidence available to date does not demonstrate a direct causal link between wind turbine noise and adverse health effects. The sound level from wind turbines at common residential setbacks is not sufficient to cause hearing impairment or other direct health effects, although some people may find it annoying. 41 refs., 1 appendix.

  3. Impact of wind turbines on birds

    International Nuclear Information System (INIS)

    Clausager, I.; Nohr, H.

    1996-01-01

    The paper is a review of the present knowledge on impacts of wind turbines on birds, requested by the Danish Ministry of the Environment and Energy. The main conclusions of the review are, that in nearly all the studies so far the numbers of birds recorded colliding with wind turbines have been limited. Some studies indicate that stationary (breeding) birds inside the wind turbine area in the short run habituate to wind turbines, especially the noise and visual impacts, and that the risk for collision becomes low. However, some of the few more long term studies indicate that a negative impact may occur in later generations of breeding birds. In some studies a disturbance effect on bird species, which temporarily stay inside a wind turbine area in order to forage or rest, is observed. The degree of impact is species-specific. An effect is typically recorded inside a zone of up to 250-800 m, with geese and waders as the most sensitive groups of birds. (author)

  4. Impact of wind turbines on birdlife

    International Nuclear Information System (INIS)

    Benner, J.H.B.; Berkhuizen, J.C.; De Graaff, R.J.; Postma, A.D.; Hendriks, J.H.W.

    1993-05-01

    An overview of wind energy programmes is presented, as well as an analysis of recent studies on the title subject and data on the attitude of nature conservation organisations both from the USA and Europe. The studies were analyzed for legitimacy of assumptions and validity of the conclusions. Most of the wind energy programs and all European studies deal with bird kills and disturbance in coastal areas. The number of victims per turbine per year in this type of area appears to be acceptable. The disturbing effect of wind turbines on breeding birds appears to be negligible. The disturbance of resting and migrating birds by wind turbines however is reasonably clear. As a result of international concern several sites have been designated where siting of wind turbines is prohibited. Well known examples are wetlands of international importance (Ramsar-convention) and European Community Special Protection Areas. Major concern among conservationists is the location of many valuable and vulnerable environmental resources outside the protected areas. Negative attitudes towards wind energy projects are not particularly due to avian considerations, but rather to a general objective to protect landscapes and habitats, undisturbed by human infrastructures and disturbance. It is concluded that all new locations for wind energy projects should be weighed on the disturbance aspect. Reference data for such a weigh are available for coastal areas, although the impact on local migration between feeding grounds and high water refugee areas needs further research. Future research is also needed for application of wind energy both on off-shore locations, grasslands and farmlands. Wind energy developers and conservationists should have a close contact in order to establish consensus on how to deal with remaining uncertainties. 7 figs., 9 tabs., 5 appendices, 37 refs

  5. Grid integration impacts on wind turbine design and development

    DEFF Research Database (Denmark)

    Hansen, Anca Daniela; Cutululis, Nicolaos Antonio; Sørensen, Poul Ejnar

    2009-01-01

    This paper presents an overall perspective on contemporary issues like wind power plants and grid integration. The purpose is to present and discuss the impacts of emerging new grid connection requirements on modern wind turbines. The grid integration issue has caused several new challenges...... to the wind turbine design and development. The survival of different wind turbine concepts and controls is strongly conditioned by their ability to comply with stringent grid connection requirements, imposed by utility companies. Beside its impact on the mechanical design and control of wind turbines......, the grid integration aspect has also an effect on wind turbines' role in the power system, on wind turbine technologies' survival on the market, as well as on the wind turbines' loads. Over the last years, it became obviously, that there it is an increasing need for design and research of wind turbines...

  6. Grid faults' impact on wind turbine structural loads

    DEFF Research Database (Denmark)

    Hansen, Anca Daniela; Cutululis, Nicolaos Antonio; Iov, F.

    2007-01-01

    The objective of this work is to illustrate the impact of the grid faults on the wind turbine structural loads. Grid faults are typically simulated in detailed power system simulation tools, which by applying simplified mechanical models, are not able to provide a throughout insight...... on the structural loads caused by sudden disturbances on the grid. On the other hand, structural loads of the wind turbine are typically assessed in advanced aerolastic computer codes, which by applying simplified electrical models do not provide detailed electrical insight. This paper presents a simulation...... of the wind turbine during grid faults. The effect of a grid fault on the wind turbine flexible structure is assessed for a typical fixed speed wind turbine, equipped with an induction generator....

  7. Analysis of the Environmental Impact on Remanufacturing Wind Turbines

    Science.gov (United States)

    Sosa Skrainka, Manuel R.

    To deliver clean energy the use of wind turbines is essential. In June 2011 there was an installed wind capacity equivalent to 211,000MW world-wide (WWEA, 2011). By the end of the year 2009 the U.S. had 35,100MW of wind energy installed capacity to generate electricity (AWEA, 2010). This industry has grown in recent years and is expected to grow even more in the future. The environmental impacts that will arise from the increased number of wind turbines and their end-of-life should be addressed, as large amounts of resources will be required to satisfy the current and future market demands for wind turbines. Since future 10MW wind turbines are expected to be as heavy as 1000 tons each, the study of the environmental response of profitable retirement strategies, such as remanufacturing for these machines, must be considered. Because of the increased number of wind turbines and the materials used, this study provides a comparison between the environmental impacts from remanufacturing the components installed inside the nacelle of multi-megawatt wind turbines and wind turbines manufactured using new components. The study methodology is the following: • Describe the life-cycle and the materials and processes employed for the manufacture and remanufacturing for components inside the nacelle. • Identify remanufacturing alternatives for the components inside the nacelle at the end of the expected life-time service of wind turbines. • Evaluate the environmental impacts from the remanufactured components and compare the results with the impacts of the manufacturing of new components using SimaPro. • Conduct sensitivity analysis over the critical parameters of the life cycle assessment • Propose the most environmentally friendly options for the retirement of each major component of wind turbines. After an analysis of the scenarios the goal of the study is to evaluate remanufacturing as an end-of-life option from an environmental perspective for commercial multi

  8. Impact of wind turbine noise in the Netherlands.

    Science.gov (United States)

    Verheijen, Edwin; Jabben, Jan; Schreurs, Eric; Smith, Kevin B

    2011-01-01

    The Dutch government aims at an increase of wind energy up to 6 000 MW in 2020 by placing new wind turbines on land or offshore. At the same time, the existing noise legislation for wind turbines is being reconsidered. For the purpose of establishing a new noise reception limit value expressed in L den , the impact of wind turbine noise under the given policy targets needs to be explored. For this purpose, the consequences of different reception limit values for the new Dutch noise legislation have been studied, both in terms of effects on the population and regarding sustainable energy policy targets. On the basis of a nation-wide noise map containing all wind turbines in The Netherlands, it is calculated that 3% of the inhabitants of The Netherlands are currently exposed to noise from wind turbines above 28 dB(A) at the faηade. Newly established dose-response relationships indicate that about 1500 of these inhabitants are likely to be severely annoyed inside their dwellings. The available space for new wind turbines strongly depends on the noise limit value that will be chosen. This study suggests an outdoor A-weighted reception limit of L den = 45 dB as a trade-off between the need for protection against noise annoyance and the feasibility of national targets for renewable energy.

  9. Gone with the wind? The impact of wind turbines on tourism demand

    International Nuclear Information System (INIS)

    Broekel, Tom; Alfken, Christoph

    2015-01-01

    While wind energy production is relatively free from environmental externalities such as air pollution, it is frequently considered to negatively impact landscapes' visual aesthetic values, thereby inducing negative effects on tourism demand. Existing evidence for Germany indeed points towards a negative relationship between tourism demand and wind turbine construction. However, the existing studies primarily rely on interview data and simple bivariate statistics. In contrast, we make use of secondary statistics on tourism and wind turbine locations at the level of German municipalities. Using spatial panel regression techniques, we confirm a negative relation between wind turbines around municipalities and tourism demand for municipalities not located near the coast. In the latter regions, the relation between wind turbines and tourism demand is more complex. - Highlights: • Comprehensive quantitative empirical study on wind turbines and tourism demand. • Consideration of wind turbines in vacation municipalities and in their geographic surroundings. • Novel data set on wind turbines and touristic demand in all German municipalities. • Application of spatial panel analysis in the context of tourism research. • Evidence for a negative relationship between wind turbines and tourism demand.

  10. Conference on wind turbines impact on birds and bats

    International Nuclear Information System (INIS)

    Ratzbor, Guenter; Dubourg-Savage, Marie-Jo; Andre, Yann; Kirchstetter, France; Bungart, Rolf; Neau, Paul; Gruendonner, Dieter; Lagrange, Hubert; Rufray, Vincent; Prie, Vincent; Haquart, Alexandre; Melki, Frederic; Fonio, Joseph; Brinkmann, Robert; Hoetker, Hermann; Grajetzki, Bodo; Mammen, Ubbo; Fagot, Guillaume; Hill, Reinhold

    2008-01-01

    The French-German office for Renewable energies (OFAEnR) organised a conference on wind turbines impacts on birds and bats. In the framework of this French-German exchange of experience, more than 85 participants exchanged views on the impacts of wind energy development on birds and bats mortality, the legal aspects, the research programs and the remedial actions. This document brings together the available presentations (slides) made during this event: 1 - Wind energy and nature protection - Is there really a conflict? (Guenter Ratzbor); 2 - Taking bats into account in wind energy projects in the European legal framework (Marie-Jo Dubourg-Savage); 3 - Wind energy-biodiversity national program - Towards a biodiversity label for wind farms (Yann Andre); 4 - Development, construction and operation of a bats-friendly wind farm in France? (France Kirchstetter); 5 - Practical experience of bats protection rules in the framework of German wind energy projects - Examples taken from projects development (Rolf Bungart); 6 - Inclusion of birds and bats issues in wind energy planning documents: schemes and wind energy development area (Paul Neau); 7 - Inclusion of potential threats for birds and bats in the definition of wind energy exploitation areas in Germany (Dieter Gruendonner); 8 - Chirotech - Conciliation between wind energy development and bats preservation - Data collection status, first results and perspectives (Hubert Lagrange, Joseph Fonio); 9 - Bats and wind energy in Germany - Present day situation and research works for conflicts resolution (Robert Brinkmann); 10 - Wind turbines and raptors in Germany: experience gained and presentation of a new research project (Hermann Hoetker); 11 - Birds fauna analysis in the framework of the development of the Cote d'Albatre offshore wind energy project (Guillaume Fagot); 12 - Birds flight remote study methods around FINO 1 (Reinhold Hill)

  11. Aspects of a potential impact of wind turbines on birds

    Directory of Open Access Journals (Sweden)

    Gabriel Fischer

    2005-11-01

    Full Text Available The electricity generated from renewable energy resources is an environmentally-preferred alternative to the conventionally produced electricity from fossil fuel and nuclear power plants. As the demand for a clean energy increases, the wind power generating stations are being constructed across Europe. However, concerns have been raised about the possible environmental impact of these turbines on birds. A research in this area has focused primarily on the mortality caused by birds striking turbine blades and associated wires. The disturbance to breeding, wintering or staging birds as a result of turbines has not been examined in detail. With respect to avian mortality at wind power generating stations, the greatest concern has been for raptors and migrating songbirds. The concern for raptors generally stems from the fact that many populations are small and thus even a few deaths can lead to declines. Songbirds are also considered at risk because they are known to fly into human-made structures (e.g. office towers, TV/microwave towers causing, on occasion, mass kills of thousands of individuals. While raptors and songbirds are generally at greatest risk of injury or death from turbines, the impact of such structures on all bird species should be considered on a site-by-site basis. Generally is possible to say that collisions with transmission and distribution lines, automobiles, trucks, tall building, residential house windows and lighted communication towers are more important for the avian mortality than the wind power generating stations.

  12. The Impact of Offshore Wind Turbines on Underwater Ambient Noise Levels

    OpenAIRE

    Glegg, Stewart

    2015-01-01

    The underwater sound levels generated by offshore wind turbine farms is a concern because of the possible environmental impact on marine mammals. This paper will consider how sound generated by a wind turbine is transmitted into a shallow water channel. It is shown that the underwater sound levels can be calculated for a typical offshore wind turbine by using the theory of Chapman and Ward (1990) combined with aeroacoustic models of trailing edge noise on the wind turbine blades. A procedure ...

  13. Investigating the Impact of Wind Turbines on Distribution System Stability

    Energy Technology Data Exchange (ETDEWEB)

    Jain, Rishabh; Zhang, Yingchen; Hodge, Bri-Mathias

    2016-12-12

    Modern wind turbines utilize power electronic converters to regulate their output and optimize their performance. Their impact on the distribution system is not as well understood as for transmission system. The novelty of this work is in studying the impact of wind turbines given its proximity to faults or severe voltage events, and the influence on system stability given its location relative to the substation (representing the conventional grid). This paper presents the frequency and voltage swing plots for various study scenarios. The responses are analyzed two fold - Steady state operation, and performance given a fault or voltage events occurs in the system. The findings are presented, with crucial differences from transmission systems highlighted.

  14. Impact of tower modeling on wind turbine wakes

    Science.gov (United States)

    Kleusberg, Elektra; Schlatter, Philipp; Henningson, Dan

    2017-11-01

    Recent research suggests the importance of modeling the support structure (tower and nacelle) when investigating the wake development behind wind turbines. These investigations are however mostly limited to low ambient turbulence levels which seldomly occur in field conditions. We present numerical simulations of wind turbine wakes using the actuator line method under different inflow conditions including varying turbulence levels and sheared inflow. The wind turbine, which employs the NREL S826 airfoil, is modeled after experiments conducted at the Norwegian University of Science and Technology. The rotor is investigated when perpendicular to the inflow and at a yaw angle of 30 degrees. The support structure is modeled using lift and drag body forces based on tabulated data. The simulations are performed with the spectral-element code Nek5000. After discussing the setup of the numerical domain and the turbulent inflow boundary condition, the influence of the tower model is characterized under turbulent, sheared and uniform inflow and the impact on downstream turbines is evaluated.

  15. Wind turbine

    Science.gov (United States)

    Cheney, Jr., Marvin C.

    1982-01-01

    A wind turbine of the type having an airfoil blade (15) mounted on a flexible beam (20) and a pitch governor (55) which selectively, torsionally twists the flexible beam in response to wind turbine speed thereby setting blade pitch, is provided with a limiter (85) which restricts unwanted pitch change at operating speeds due to torsional creep of the flexible beam. The limiter allows twisting of the beam by the governor under excessive wind velocity conditions to orient the blades in stall pitch positions, thereby preventing overspeed operation of the turbine. In the preferred embodiment, the pitch governor comprises a pendulum (65,70) which responds to changing rotor speed by pivotal movement, the limiter comprising a resilient member (90) which engages an end of the pendulum to restrict further movement thereof, and in turn restrict beam creep and unwanted blade pitch misadjustment.

  16. The Electromagnetic Impact of Wind Turbines

    Science.gov (United States)

    2015-07-06

    Network Test Directorate CanWEA Canadian Wind Energy Association CFAR constant false alarm rate CIED counter improvised explosive device COTS...changing threshold level is lowered and raised to maintain the constant probability of false alarm. This is known as constant false alarm rate ( CFAR

  17. Integrated analysis of wind turbines - The impact of power systems on wind turbine design

    DEFF Research Database (Denmark)

    Barahona Garzón, Braulio

    of the integrated simulation environment are presented. The analysis of an asynchronous machine, and numerical simulations of a fixedspeed wind turbine in the integrated simulation environment, demonstrate the effects on structural loads of including the generator rotor fluxes dynamics in aeroelastic studies. Power...

  18. Wind Turbine Control Impact on Stability of Wind Farms Based on Real-Life Systems Analysis

    DEFF Research Database (Denmark)

    Kocewiak, Lukasz Hubert; Hjerrild, Jesper; Bak, Claus Leth

    2012-01-01

    that wind farm components such as long HVAC cables and park transformers can introduce significant low-frequency series resonances seen form the wind turbine terminals which can affect wind turbine control system operation and overall wind farm stability. The same wind turbine converter control strategy...

  19. Wind turbines and infrasound

    International Nuclear Information System (INIS)

    Howe, B.

    2006-01-01

    This paper provided the results of a study conducted to assess the impacts of wind farm-induced infrasound on nearby residences and human populations. Infrasound occurs at frequencies below those considered as detectable by human hearing. Infrasonic levels caused by wind turbines are often similar to ambient levels of 85 dBG or lower that are caused by wind in the natural environment. This study examined the levels at which infrasound poses a threat to human health or can be considered as an annoyance. The study examined levels of infrasound caused by various types of wind turbines, and evaluated acoustic phenomena and characteristics associated with wind turbines. Results of the study suggested that infrasound near modern wind turbines is typically not perceptible to humans through either auditory or non-auditory mechanisms. However, wind turbines often create an audible broadband noise whose amplitude can be modulated at low frequencies. A review of both Canadian and international studies concluded that infrasound generated by wind turbines should not significantly impact nearby residences or human populations. 17 refs., 2 tabs., 4 figs

  20. Assessment of the impact of frequency support on DFIG wind turbine loads

    DEFF Research Database (Denmark)

    Barahona Garzón, Braulio; You, Rui; Hansen, Anca Daniela

    2013-01-01

    This study presents models and tools for the assessment of the impact that providing frequency support has on doubly-fed generator (DFIG) wind turbine structural loads and drive train. The focus is on primary frequency support, aiming at quantifying the impact on wind turbines acting as frequency...

  1. Grid impact of variable-speed wind turbines

    Energy Technology Data Exchange (ETDEWEB)

    Larsson, Aa. [Chalmers Univ. of Technology, Dept. of Electric Power Engineering, Goeteborg (Sweden); Soerensen, P. [Risoe National Lab., Roskilde (Denmark); Santjer, F. [German Wind Energy Inst., DEWI, Wilhelmshaven (Germany)

    1999-03-01

    In this paper the power quality of variable-speed wind turbines equipped with forced-commutated inverters is investigated. Measurements have been taken on the same type of variable-speed wind turbines in Germany and Sweden. The measurements have been analysed according to existing IEC standards. Special attention has been paid to the aggregation of several wind turbines on flicker emission and harmonics. The aggregation has been compared with the summation laws used in the draft IEC 61400-21 `Power Quality Requirements for Grid Connected wind turbines`. The methods for calculating and summing flicker proposed by IEC Standards are reliable. Harmonics and inter-harmonics are treated in IEC 61000-4-7 and IEC 61000-3-6. The methods for summing harmonics and inter-harmonics in IEC 61000-3-6 are applicable to wind turbines. In order to obtain a correct magnitude of the frequency components, the use of a well-defined window width, according to IEC 61000-4-7 Amendment 1 is of a great importance. (au)

  2. Antenna Gain Impact on UWB Wind Turbine Blade Deflection Sensing

    DEFF Research Database (Denmark)

    Zhang, Shuai; Franek, Ondrej; Byskov, Claus

    2018-01-01

    effective (or equivalent) isotropic radiated power (EIRP), an HG tip antenna inside a blade gives stronger direct pulse amplitudes and better pulse waveforms for accurate and reliable distance estimations than the LG. Moreover, the direct pulse with the HG antenna is also closer to the blade surface, which...... a blade). Higher antenna gain enlarges both direct pulse and multipath but in different levels. To verify the simulations, time-domain measurements are performed with a full 37-meter blade. Pulse waveforms and power delay profiles are measured. From all the studies, it follows that: with the similar......Antenna gain impact on UWB wind turbine blade deflection sensing is studied in this paper. Simulations are applied with a 4.5-meter blade tip. The antennas with high gain (HG) and low gain (LG) in free space are simulated inside a blade. It is interesting to find that tip antennas with HG and LG...

  3. Evaluating the impact of electrical grid connection on the wind turbine performance for Hofa wind farm scheme in Jordan

    International Nuclear Information System (INIS)

    Abderrazzaq, M.H.; Aloquili, O.

    2008-01-01

    The growth of wind energy is attributed to the development of turbine size and the increase in number of units in each wind farm. The current modern design of large wind turbines (WT) is directed towards producing efficient, sensitive and reliable units. To achieve this goal, modern turbines are equipped with several devices which are operated with highly advanced electronic circuits. Sensing instruments, measuring devices and control processes of major systems and subsystems are based on various types of electronic apparatus and boards. These boards are very sensitive to the voltage variations caused by abnormal conditions in both the turbine itself and the electric grid to which the wind farm is connected. This paper evaluates wind farm records and proposes a number of methods to overcome such obstacles associated with the design of large wind turbines. Several cases of grid abnormality such as sudden feeder interruption due to the short circuit, network disconnection, voltage variation and circuit breaker opening affecting wind turbines operation and availability are classified and presented. The weight of such impact is determined for each type of disturbances associated with electronic problems in the wind turbine. Wind turbine performance at Hofa wind farm scheme in Jordan is taken as a case study

  4. Wind turbines and health

    International Nuclear Information System (INIS)

    Rideout, K.; Copes, R.; Bos, C.

    2010-01-01

    This document summarized the potential health hazards associated with wind turbines, such as noise and low frequency sound, vibration and infrasound; electromagnetic fields (EMF); shadow flicker; and ice throw and structural failure. Various symptoms can be attributed to wind turbines, including dizziness, sleep disruption, and headaches. A review of available research regarding potential health affects to residents living in close proximity to wind turbines showed that the sound level associated with wind turbines at common residential setbacks is not sufficient to damage hearing, but may lead to annoyance and sleep disturbance. Research has shown that wind turbines are not a significant source of EMF exposure, and although shadows caused by the blades may be annoying, they are not likely to cause epileptic seizures at normal operational speeds. The risk of injury from ice throw can be minimized with setbacks of 200 to 400 m. Examples of Canadian wind turbine setback guidelines and regulations were also offered. It was concluded that setbacks and operational guidelines can be utilized in combination to address safety hazards, sound levels, land use issues, and impacts on people. 46 refs., 2 tabs., 2 figs.

  5. Wind turbines and health

    Energy Technology Data Exchange (ETDEWEB)

    Rideout, K.; Copes, R.; Bos, C. [National Colaborating Centre for Environmental Health, Vancouver, BC (Canada)

    2010-01-15

    This document summarized the potential health hazards associated with wind turbines, such as noise and low frequency sound, vibration and infrasound; electromagnetic fields (EMF); shadow flicker; and ice throw and structural failure. Various symptoms can be attributed to wind turbines, including dizziness, sleep disruption, and headaches. A review of available research regarding potential health affects to residents living in close proximity to wind turbines showed that the sound level associated with wind turbines at common residential setbacks is not sufficient to damage hearing, but may lead to annoyance and sleep disturbance. Research has shown that wind turbines are not a significant source of EMF exposure, and although shadows caused by the blades may be annoying, they are not likely to cause epileptic seizures at normal operational speeds. The risk of injury from ice throw can be minimized with setbacks of 200 to 400 m. Examples of Canadian wind turbine setback guidelines and regulations were also offered. It was concluded that setbacks and operational guidelines can be utilized in combination to address safety hazards, sound levels, land use issues, and impacts on people. 46 refs., 2 tabs., 2 figs.

  6. Superconducting Wind Turbine Generators

    OpenAIRE

    Yunying Pan; Danhzen Gu

    2016-01-01

    Wind energy is well known as a renewable energy because its clean and less polluted characteristic, which is the foundation of development modern wind electricity. To find more efficient wind turbine is the focus of scientists around the world. Compared from conventional wind turbines, superconducting wind turbine generators have advantages at zero resistance, smaller size and lighter weight. Superconducting wind turbine will inevitably become the main trends in this area. This paper intends ...

  7. Wind Turbine Acoustics

    Science.gov (United States)

    Hubbard, Harvey H.; Shepherd, Kevin P.

    2009-01-01

    Wind turbine generators, ranging in size from a few kilowatts to several megawatts, are producing electricity both singly and in wind power stations that encompass hundreds of machines. Many installations are in uninhabited areas far from established residences, and therefore there are no apparent environmental impacts in terms of noise. There is, however, the potential for situations in which the radiated noise can be heard by residents of adjacent neighborhoods, particularly those neighborhoods with low ambient noise levels. A widely publicized incident of this nature occurred with the operation of the experimental Mod-1 2-MW wind turbine, which is described in detail elsewhere. Pioneering studies which were conducted at the Mod-1 site on the causes and remedies of noise from wind turbines form the foundation of much of the technology described in this chapter.

  8. Introduction to wind turbine aerodynamics

    CERN Document Server

    Schaffarczyk, Alois Peter

    2014-01-01

    Wind-Turbine Aerodynamics is a self-contained textbook which shows how to come from the basics of fluid mechanics to modern wind turbine blade design. It presents a fundamentals of fluid dynamics and inflow conditions, and gives a extensive introduction into theories describing the aerodynamics of wind turbines. After introducing experiments the book applies the knowledge to explore the impact on blade design.The book is an introduction for professionals and students of very varying levels.

  9. Model of wind shear conditional on turbulence and its impact on wind turbine loads

    DEFF Research Database (Denmark)

    Dimitrov, Nikolay Krasimirov; Natarajan, Anand; Kelly, Mark C.

    2015-01-01

    fatigue load is achieved. The proposed wind shear model based on the wind measurements is thereby probabilistic in definition, with shear jointly distributed with wind turbulence. A simplified model for the wind shear exponent is further derived from the full stochastic model. The fatigue loads over......We analyse high-frequency wind velocity measurements from two test stations over a period of several years and at heights ranging from 60 to 200 m, with the objective to validate wind shear predictions as used in load simulations for wind turbine design. A validated wind shear model is thereby...... different turbine components are evaluated under the full wind measurements, using the developed wind shear model and with standard wind conditions prescribed in the IEC 61400-1 ed. 3. The results display the effect of the Wöhler exponent and reveal that under moderate turbulence, the effect of wind shear...

  10. Grid Faults Impact on the Mechanical Loads of Active Stall Wind Turbine

    DEFF Research Database (Denmark)

    Iov, Florin; Cutululis, Nicolaos A.; Hansen, Anca D.

    2008-01-01

    Emphasis in this paper is on the fault ride-through operation impact on the wind turbines structural loads. Grid faults are typically simulated in power system simulation tools using simplified drive train mechanical model, approach which doesn't allow a thorough investigation of structural loads...... as the electrical design of the wind turbine response during grid faults. The two-step simulation procedure is assessed by means of a simulation example. The effect of a grid fault on the structural part of a typical fixed speed wind turbine, equipped with an induction generator, is assessed....

  11. Impacts of Providing Inertial Response on Dynamic Loads of Wind Turbine Drivetrains: Preprint

    Energy Technology Data Exchange (ETDEWEB)

    Girsang, I. P.; Dhupia, J.; Singh, M.; Gevorgian, V.; Muljadi, E.; Jonkman, J.

    2014-09-01

    There has been growing demand from the power industry for wind power plants to support power system operations. One such requirement is for wind turbines to provide ancillary services in the form of inertial response. When the grid frequency drops, it is essential for wind turbine generators (WTGs) to inject kinetic energy stored in their inertia into the grid to help arrest the frequency decline. However, the impacts of inertial response on the structural loads of the wind turbine have not been given much attention. To bridge this gap, this paper utilizes a holistic model for both fixed-speed and variable-speed WTGs by integrating the aeroelastic wind turbine model in FAST, developed by the National Renewable Energy Laboratory, with the electromechanical drivetrain model in SimDriveline and SimPowerSystems.

  12. Turbulence and wind turbines

    DEFF Research Database (Denmark)

    Brand, Arno J.; Peinke, Joachim; Mann, Jakob

    2011-01-01

    The nature of turbulent flow towards, near and behind a wind turbine, the effect of turbulence on the electricity production and the mechanical loading of individual and clustered wind turbines, and some future issues are discussed.......The nature of turbulent flow towards, near and behind a wind turbine, the effect of turbulence on the electricity production and the mechanical loading of individual and clustered wind turbines, and some future issues are discussed....

  13. 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...

  14. Wind Turbine Technologies

    DEFF Research Database (Denmark)

    Hansen, Anca Daniela

    2017-01-01

    The wind turbine technology is a very complex technology involving multidisciplinary and broad technical disciplines such as aerodynamics, mechanics, structure dynamics, meteorology as well as electrical engineering addressing the generation, transmission, and integration of wind turbines...... into the power system. Wind turbine technology has matured over the years and become the most promising and reliable renewable energy technology today. It has moved very fast, since the early 1980s, from wind turbines of a few kilowatts to today’s multimegawatt-sized wind turbines [13]. Besides their size......, the design of wind turbines has changed from being convention driven to being optimized driven within the operating regime and market environment. Wind turbine designs have progressed from fixed speed, passive controlled and with drive trains with gearboxes, to become variable speed, active controlled...

  15. Aerodynamics of Wind Turbines

    DEFF Research Database (Denmark)

    Hansen, Martin Otto Laver

    Aerodynamics of Wind Turbines is the established essential text for the fundamental solutions to efficient wind turbine design. Now in its second edition, it has been entirely updated and substantially extended to reflect advances in technology, research into rotor aerodynamics and the structural...... response of the wind turbine structure. Topics covered include increasing mass flow through the turbine, performance at low and high wind speeds, assessment of the extreme conditions under which the turbine will perform and the theory for calculating the lifetime of the turbine. The classical Blade Element...... Momentum method is also covered, as are eigenmodes and the dynamic behavior of a turbine. The new material includes a description of the effects of the dynamics and how this can be modeled in an aeroelastic code, which is widely used in the design and verification of modern wind turbines. Further...

  16. Aerodynamics of wind turbines

    DEFF Research Database (Denmark)

    Hansen, Martin Otto Laver

    Aerodynamics of Wind Turbines is the established essential text for the fundamental solutions to efficient wind turbine design. Now in its third edition, it has been substantially updated with respect to structural dynamics and control. The new control chapter now includes details on how to design...... Turbines (VAWT). Topics covered include increasing mass flow through the turbine, performance at low and high wind speeds, assessment of the extreme conditions under which the turbine will perform and the theory for calculating the lifetime of the turbine. The classical Blade Element Momentum method...... is also covered, as are eigenmodes and the dynamic behaviour of a turbine. The book describes the effects of the dynamics and how this can be modelled in an aeroelastic code, which is widely used in the design and verification of modern wind turbines. Furthermore, it examines how to calculate...

  17. Wind Turbines Wake Aerodynamics

    DEFF Research Database (Denmark)

    Vermeer, L.; Sørensen, Jens Nørkær; Crespo, A.

    2003-01-01

    The aerodynamics of horizontal axis wind turbine wakes is studied. The contents is directed towards the physics of power extraction by wind turbines and reviews both the near and the far wake region. For the near wake, the survey is restricted to uniform, steady and parallel flow conditions......, thereby excluding wind shear, wind speed and rotor setting changes and yawed conditions. The emphasis is put on measurements in controlled conditions.For the far wake, the survey focusses on both single turbines and wind farm effects, and the experimental and numerical work are reviewed; the main interest...... is to study how the far wake decays downstream, in order to estimate the effect produced in downstream turbines.The article is further restricted to horizontal axis wind turbines and excludes all other types of turbines....

  18. 75 FR 29365 - Job Corps: Final Finding of No Significant Impact (FONSI) for Small Wind Turbine Installation at...

    Science.gov (United States)

    2010-05-25

    ... DEPARTMENT OF LABOR Office of the Secretary Job Corps: Final Finding of No Significant Impact (FONSI) for Small Wind Turbine Installation at the Pine Ridge Job Corps Center Located at 15710 Highway... Finding of No Significant Impact (FONSI) for Small Wind Turbine Installation at the Pine Ridge Job Corps...

  19. Session: Monitoring wind turbine project sites for avian impacts

    Energy Technology Data Exchange (ETDEWEB)

    Erickson, Wally

    2004-09-01

    This third session at the Wind Energy and Birds/Bats workshop consisted of one presentation followed by a discussion/question and answer period. The focus of the session was on existing wind projects that are monitored for their impacts on birds and bats. The presentation given was titled ''Bird and Bat Fatality Monitoring Methods'' by Wally Erickson, West, Inc. Sections included protocol development and review, methodology, adjusting for scavenging rates, and adjusting for observer detection bias.

  20. Assessing spacing impact on coherent features in a wind turbine array boundary layer

    Directory of Open Access Journals (Sweden)

    N. Ali

    2018-02-01

    intermediate scales are responsible for features seen in the original profile. The variation in streamwise and spanwise spacing leads to changes in the background structure of the turbulence, where the color map based on barycentric map and Reynolds stress anisotropy tensor provides an alternate perspective on the nature of the perturbations within the wind turbine array. The impact of the streamwise and spanwise spacings on power produced is quantified, where the maximum production corresponds with the case of greatest turbine spacing.

  1. Evaluating the impact of wind turbine noise on health-related quality of life.

    Science.gov (United States)

    Shepherd, Daniel; McBride, David; Welch, David; Dirks, Kim N; Hill, Erin M

    2011-01-01

    We report a cross-sectional study comparing the health-related quality of life (HRQOL) of individuals residing in the proximity of a wind farm to those residing in a demographically matched area sufficiently displaced from wind turbines. The study employed a nonequivalent comparison group posttest-only design. Self-administered questionnaires, which included the brief version of the World Health Organization quality of life scale, were delivered to residents in two adjacent areas in semirural New Zealand. Participants were also asked to identify annoying noises, indicate their degree of noise sensitivity, and rate amenity. Statistically significant differences were noted in some HRQOL domain scores, with residents living within 2 km of a turbine installation reporting lower overall quality of life, physical quality of life, and environmental quality of life. Those exposed to turbine noise also reported significantly lower sleep quality, and rated their environment as less restful. Our data suggest that wind farm noise can negatively impact facets of HRQOL.

  2. Aerodynamics of wind turbines

    DEFF Research Database (Denmark)

    Hansen, Martin Otto Laver

    Aerodynamics of Wind Turbines is the established essential text for the fundamental solutions to efficient wind turbine design. Now in its third edition, it has been substantially updated with respect to structural dynamics and control. The new control chapter now includes details on how to design...... a classical pitch and torque regulator to control rotational speed and power, while the section on structural dynamics has been extended with a simplified mechanical system explaining the phenomena of forward and backward whirling modes. Readers will also benefit from a new chapter on Vertical Axis Wind...... Turbines (VAWT). Topics covered include increasing mass flow through the turbine, performance at low and high wind speeds, assessment of the extreme conditions under which the turbine will perform and the theory for calculating the lifetime of the turbine. The classical Blade Element Momentum method...

  3. Aerodynamics of wind turbines

    DEFF Research Database (Denmark)

    Hansen, Martin Otto Laver

    Aerodynamics of Wind Turbines is the established essential text for the fundamental solutions to efficient wind turbine design. Now in its third edition, it has been substantially updated with respect to structural dynamics and control. The new control chapter now includes details on how to design...

  4. Aerodynamics of Wind Turbines

    DEFF Research Database (Denmark)

    Hansen, Martin Otto Laver

    Aerodynamics of Wind Turbines is the established essential text for the fundamental solutions to efficient wind turbine design. Now in its second edition, it has been entirely updated and substantially extended to reflect advances in technology, research into rotor aerodynamics and the structural...

  5. Small wind turbine

    OpenAIRE

    Vélez Castellano, Didier

    2010-01-01

    The main objective is to develop a project on installing a small wind turbine at the University of Glyndwr in Wrexham Wales. Today are immersed in a world seeking clean energy for reduce greenhouse gases because this problem is becoming a global reality. So installing a small wind turbine at the university would provide large quantity of clean energy to supply a workshop and also reduce the expulsion of CO2 into the atmosphere. The main characteristic of the turbine under...

  6. On the impact of non-Gaussian wind statistics on wind turbines – an experimental approach

    Directory of Open Access Journals (Sweden)

    J. Schottler

    2017-01-01

    Full Text Available The effect of intermittent and Gaussian inflow conditions on wind energy converters is studied experimentally. Two different flow situations were created in a wind tunnel using an active grid. Both flows exhibit nearly equal mean velocity values and turbulence intensities but strongly differ in their two point statistics, namely their distribution of velocity increments on a variety of timescales, one being Gaussian distributed, and the other one being strongly intermittent. A horizontal axis model wind turbine is exposed to both flows, isolating the effect on the turbine of the differences not captured by mean values and turbulence intensities. Thrust, torque and power data were recorded and analyzed, showing that the model turbine does not smooth out intermittency. Intermittent inflow is converted to similarly intermittent turbine data on all scales considered, reaching down to sub-rotor scales in space. This indicates that it is not correct to assume a smoothing of intermittent wind speed increments below the size of the rotor.

  7. Environmental impacts of micro-wind turbines and their potential to contribute to UK climate change targets

    International Nuclear Information System (INIS)

    Greening, Benjamin; Azapagic, Adisa

    2013-01-01

    This paper evaluates the life cycle environmental sustainability of micro-wind turbines in the UK in comparison with grid electricity and solar PV (photovoltaics). The results suggests that per kWh electricity generated, the majority of environmental impacts from the wind turbines are lower than from grid electricity, ranging from 26% lower terrestrial toxicity to 92% lower global warming. However, depletion of abiotic elements, fresh-water and human toxicities are 82%, 74% and 53% higher than for grid electricity, respectively. The wind turbines are more environmentally sustainable than solar PV for seven out of 11 impacts, ranging from 7.5% lower eutrophication to 85% lower ozone layer depletion. However, depletion of fossil resources, fresh-water, human and terrestrial toxicities are higher for the wind turbine than for the PV, ranging from 5% for the former to 87% for the latter. UK-wide deployment of micro-wind turbines would save between 0.6 and 1% of GHG (greenhouse gas) emissions on 2009 levels. Therefore, the potential of micro-wind turbines to contribute towards UK's climate change targets is limited. - Highlights: • Life cycle environmental impacts of micro-wind turbines estimated for UK conditions. • The majority impacts are lower for micro-wind turbines than for grid electricity and solar PV. • Some impacts from micro-wind are higher, notably fresh-water and human toxicity. • At the national level, wind turbines would save only 0.6% GHG emissions on 2009 levels. • The potential of micro-wind turbines to contribute to UK's climate change targets is limited

  8. Wind turbine state estimation

    DEFF Research Database (Denmark)

    Knudsen, Torben

    2014-01-01

    the results using full-scale wind turbine data. The previously developed methods were based on extended Kalman filtering. This method has several drawback compared to unscented Kalman filtering which has therefore been developed. The unscented Kalman filter was first tested on linear and non-linear test cases......Dynamic inflow is an effect which is normally not included in the models used for wind turbine control design. Therefore, potential improvement from including this effect exists. The objective in this project is to improve the methods previously developed for this and especially to verify...... which was successful. Then the estimation of a wind turbine state including dynamic inflow was tested on a simulated NREL 5MW turbine was performed. This worked perfectly with wind speeds from low to nominal wind speed as the output prediction errors where white. In high wind where the pitch actuator...

  9. An experimental and numerical study of the atmospheric stability impact on wind turbine wakes

    DEFF Research Database (Denmark)

    Machefaux, Ewan; Larsen, Gunner Chr.; Koblitz, Tilman

    2016-01-01

    In this paper, the impact of atmospheric stability on a wind turbine wake is studied experimentally and numerically. The experimental approach is based on full-scale (nacelle based) pulsed lidar measurements of the wake flow field of a stall-regulated 500 kW turbine at the DTU Wind Energy, Risø...... campus test site. Wake measurements are averaged within a mean wind speed bin of 1 m s1 and classified according to atmospheric stability using three different metrics: the Obukhov length, the Bulk–Richardson number and the Froude number. Three test cases are subsequently defined covering various...... atmospheric conditions. Simulations are carried out using large eddy simulation and actuator disk rotor modeling. The turbulence properties of the incoming wind are adapted to the thermal stratification using a newly developed spectral tensor model that includes buoyancy effects. Discrepancies are discussed...

  10. Impact of uncertainty in airfoil characteristics on wind turbine extreme loads

    DEFF Research Database (Denmark)

    Abdallah, Imad; Natarajan, Anand; Sørensen, John Dalsgaard

    2015-01-01

    Wind tunnel test measurements to characterize the static lift and drag coefficients of airfoils used in wind turbine blades are shown to possess large uncertainties, which leads to uncertainties in the aerodynamic loads on the rotor. In this paper a rational stochastic model is proposed to quantify...... the uncertainty in airfoil static lift and drag coefficients based on field and wind tunnel data, aero-servoelastic calculations and engineering judgment. The stochastic model is subsequently used to assess the effect of the uncertainty in airfoil static lift and drag coefficients on the prediction of extreme...... loads and structural reliability of large wind turbines. It is shown that the uncertainty in the static airfoil data has a significant impact on the prediction of extreme loads effects and structural reliability depending on the component, operating conditions (stand-still versus power production...

  11. Noise immission from wind turbines

    International Nuclear Information System (INIS)

    1999-01-01

    The project has dealt with practical ways to reduce the influence of background noise caused by wind acting on the measuring microphones. The uncertainty of measured noise emission (source strength) has been investigated. The main activity was a Round Robin Test involving measurements by five laboratories at the same wind turbine. Each laboratory brought its own instrumentation and performed the measurements and analyses according to their interpretation. The tonality of wind turbine noise is an essential component of the noise impact on the environment. In the present project the uncertainty in the newest existing methods for assessing tonality was investigated. The project included noise propagation measurements in different weather conditions around wind turbines situated in different types of terrain. The results were used to validate a noise propagation model developed in the project. Finally, the project also included a study with listeners evaluating recordings of wind turbine noise. The results are intended as guidance for wind turbine manufacturers in identifying the aspects of wind turbine noise most important to annoyance. (author)

  12. Noise from wind turbines

    International Nuclear Information System (INIS)

    Andersen, B.; Larsen, P.

    1993-01-01

    Denmark has 3200 wind turbines with an installed maximum capacity of 418MW. The most important Danish research projects into wind turbine noise and the main results are listed. These date from 1983. Two comprehensive studies are currently in progress. The first is an analytical and empirical investigation of aerodynamic noise from wind turbine rotors and has so far dealt mainly with tip noise. The measurement method, using a hard board mounted microphone on the ground near the turbine, is described. Four different tip designs have been tested. Some examples of reference sound power level spectra for three of the designs are presented. During the past two years a computerbased data acquisition system has been used for real-time determination of sound power levels. The second study, which has just commenced, is on annoyance from wind turbine noise. It will include noise measurements, masking calculations and a social survey on the perceived nuisance. (UK)

  13. WIND TURBINES FOR WIND POWER INSTALLATIONS

    Directory of Open Access Journals (Sweden)

    Barladean A.S.

    2008-04-01

    Full Text Available The problem of wind turbine choice for wind power stations is examined in this paper. It is shown by comparison of parameters and characteristics of wind turbines, that for existing modes and speeds of wind in territory of Republic of Moldova it is necessary to use multi-blade small speed rotation wind turbines of fan class.

  14. Aeroservoelasticity of Wind Turbines

    DEFF Research Database (Denmark)

    Kallesøe, Bjarne Skovmose

    2007-01-01

    This thesis deals with the fundamental aeroelastic interaction between structural motion, Pitch action and control for a wind turbine blade. As wind turbines become larger, the interaction between pitch action, blade motion, aerodynamic forces, and control become even more important to understand...... to a 2D blade section model, and it can be used instead of this in many applications, giving a transparent connection to a real wind turbine blade. In this work the aeroelastic blade model is used to analyze interaction between pitch action, blade motion and wind speed variations. Furthermore the model...... conditions. So, a new aeroelastic blade model has been derived, which includes important features of large wind turbines, yet simple enough to be suitable for analytical analysis and control design....

  15. An integrated audio-visual impact tool for wind turbine installations

    International Nuclear Information System (INIS)

    Lymberopoulos, N.; Belessis, M.; Wood, M.; Voutsinas, S.

    1996-01-01

    An integrated software tool was developed for the design of wind parks that takes into account their visual and audio impact. The application is built on a powerful hardware platform and is fully operated through a graphic user interface. The topography, the wind turbines and the daylight conditions are realised digitally. The wind park can be animated in real time and the user can take virtual walks in it while the set-up of the park can be altered interactively. In parallel, the wind speed levels on the terrain, the emitted noise intensity, the annual energy output and the cash flow can be estimated at any stage of the session and prompt the user for rearrangements. The tool has been used to visually simulate existing wind parks in St. Breok, UK and Andros Island, Greece. The results lead to the conclusion that such a tool can assist to the public acceptance and licensing procedures of wind parks. (author)

  16. An integrated modeling method for wind turbines

    Science.gov (United States)

    Fadaeinedjad, Roohollah

    To study the interaction of the electrical, mechanical, and aerodynamic aspects of a wind turbine, a detailed model that considers all these aspects must be used. A drawback of many studies in the area of wind turbine simulation is that either a very simple mechanical model is used with a detailed electrical model, or vice versa. Hence the interactions between electrical and mechanical aspects of wind turbine operation are not accurately taken into account. In this research, it will be shown that a combination of different simulation packages, namely TurbSim, FAST, and Simulink can be used to model the aerodynamic, mechanical, and electrical aspects of a wind turbine in detail. In this thesis, after a review of some wind turbine concepts and software tools, a simulation structure is proposed for studying wind turbines that integrates the mechanical and electrical components of a wind energy conversion device. Based on the simulation structure, a comprehensive model for a three-bladed variable speed wind turbine with doubly-fed induction generator is developed. Using the model, the impact of a voltage sag on the wind turbine tower vibration is investigated under various operating conditions such as power system short circuit level, mechanical parameters, and wind turbine operating conditions. It is shown how an electrical disturbance can cause more sustainable tower vibrations under high speed and turbulent wind conditions, which may disrupt the operation of pitch control system. A similar simulation structure is used to model a two-bladed fixed speed wind turbine with an induction generator. An extension of the concept is introduced by adding a diesel generator system. The model is utilized to study the impact of the aeroelastic aspects of wind turbine (i.e. tower shadow, wind shears, yaw error, turbulence, and mechanical vibrations) on the power quality of a stand-alone wind-diesel system. Furthermore, an IEEE standard flickermeter model is implemented in a

  17. Noise from wind turbines

    International Nuclear Information System (INIS)

    Andersen, B.; Jakobsen, J.

    1992-11-01

    Based on a previous project concerning the calculation of the amount of noise emanating from wind turbine arrays, this one examines the subject further by investigating whether there could be significant differences in the amount of noise made by individual wind turbines in an array, and whether the noise is transmitted in varying directions - so that when it is carried in the same direction as the wind blows it would appear to be louder. The aim was also to determine whether the previously used method of calculation lacked precision. It was found that differences in noise niveaux related to individual wind turbines were insignificant and that noise was not so loud when it was not borne in the direction of the wind. It was necessary to change the method of calculation as reckoning should include the influence of the terrain, wind velocity and distance. The measuring and calculation methods are exemplified and the resulting measurements are presented in detail. (AB)

  18. Wind turbine pitch optimization

    DEFF Research Database (Denmark)

    Biegel, Benjamin; Juelsgaard, Morten; Stoustrup, Jakob

    2011-01-01

    We consider a static wind model for a three-bladed, horizontal-axis, pitch-controlled wind turbine. When placed in a wind field, the turbine experiences several mechanical loads, which generate power but also create structural fatigue. We address the problem of finding blade pitch profiles......% compared to any constant pitch profile while sacrificing at most 7% of the maximum attainable output power. Using iterative learning, we show that very similar performance can be achieved by using only load measurements, with no knowledge of the wind field or wind turbine model....... for maximizing power production while simultaneously minimizing fatigue loads. In this paper, we show how this problem can be approximately solved using convex optimization. When there is full knowledge of the wind field, numerical simulations show that force and torque RMS variation can be reduced by over 96...

  19. Monitoring of wind turbines

    Science.gov (United States)

    White, Jonathan R.; Adams, Douglas E.; Paquette, Josh

    2017-07-25

    Method and apparatus for determining the deflection or curvature of a rotating blade, such as a wind turbine blade or a helicopter blade. Also, methods and apparatus for establishing an inertial reference system on a rotating blade.

  20. Vertical axis wind turbine

    International Nuclear Information System (INIS)

    Obretenov, V.; Tsalov, T.; Chakarov, T.

    2012-01-01

    In recent years, the interest in wind turbines with vertical axis noticeably increased. They have some important advantages: low cost, relatively simple structure, reliable packaging system of wind aggregate long period during which require no maintenance, low noise, independence of wind direction, etc.. The relatively low efficiency, however, makes them applicable mainly for small facilities. The work presents a methodology and software for approximately aerodynamic design of wind turbines of this type, and also analyzed the possibility of improving the efficiency of their workflow

  1. Vertical axis wind turbines

    Science.gov (United States)

    Krivcov, Vladimir [Miass, RU; Krivospitski, Vladimir [Miass, RU; Maksimov, Vasili [Miass, RU; Halstead, Richard [Rohnert Park, CA; Grahov, Jurij [Miass, RU

    2011-03-08

    A vertical axis wind turbine is described. The wind turbine can include a top ring, a middle ring and a lower ring, wherein a plurality of vertical airfoils are disposed between the rings. For example, three vertical airfoils can be attached between the upper ring and the middle ring. In addition, three more vertical airfoils can be attached between the lower ring and the middle ring. When wind contacts the vertically arranged airfoils the rings begin to spin. By connecting the rings to a center pole which spins an alternator, electricity can be generated from wind.

  2. Wind turbine state estimation

    OpenAIRE

    Knudsen, Torben

    2014-01-01

    Dynamic inflow is an effect which is normally not included in the models used for wind turbine control design. Therefore, potential improvement from including this effect exists. The objective in this project is to improve the methods previously developed for this and especially to verify the results using full-scale wind turbine data. The previously developed methods were based on extended Kalman filtering. This method has several drawback compared to unscented Kalman filtering which has the...

  3. Impact of wind turbine control strategies on voltage performance

    OpenAIRE

    Vittal, Eknath; O'Malley, Mark; Keane, Andrew

    2009-01-01

    This study examines the 2013 Irish electricity network and its ability to accommodate large levels of wind generation while maintaining appropriate voltage levels across the system. The network provides a fully functional test system that is suitable for large scale power flow and dynamic simulations. In the next decade, wind generation is expected to constitute large percentage of the country’s new renewable generation portfolio due to the rich wind resource available in...

  4. European wind turbine catalogue

    International Nuclear Information System (INIS)

    1994-01-01

    The THERMIE European Community programme is designed to promote the greater use of European technology and this catalogue contributes to the fulfillment of this aim by dissemination of information on 50 wind turbines from 30 manufacturers. These turbines are produced in Europe and are commercially available. The manufacturers presented produce and sell grid-connected turbines which have been officially approved in countries where this approval is acquired, however some of the wind turbines included in the catalogue have not been regarded as fully commercially available at the time of going to print. The entries, which are illustrated by colour photographs, give company profiles, concept descriptions, measured power curves, prices, and information on design and dimension, safety systems, stage of development, special characteristics, annual energy production, and noise pollution. Lists are given of wind turbine manufacturers and agents and of consultants and developers in the wind energy sector. Exchange rates used in the conversion of the prices of wind turbines are also given. Information can be found on the OPET network (organizations recognised by the European Commission as an Organization for the Promotion of Energy Technologies (OPET)). An article describes the development of the wind power industry during the last 10-15 years and another article on certification aims to give an overview of the most well-known and acknowledged type approvals currently issued in Europe. (AB)

  5. Simulation of shear and turbulence impact on wind turbine performance

    DEFF Research Database (Denmark)

    Wagner, Rozenn; Courtney, Michael; Larsen, Torben J.

    of a uniform inflow. Secondly, a similar analysis was done for cases with direction shear. In each case, we derived a standard power curve (function of the wind speed at hub height) and power curves obtained with various definitions of equivalent wind speed in order to reduce the scatter due to shear. Thirdly...

  6. Impact of wind turbine based on double feed induction generator and FACTS devices on power systems

    Directory of Open Access Journals (Sweden)

    Labiba ADJOUDJ

    2015-05-01

    Full Text Available Integration of wind turbines may have significant impacts on power system operation and generation of electricity from wind power has received considerable attention. This paper analyses the impact of integrating wind generation based on double feed induction generators (DFIG and Flexible AC Transmission System (FACTS on the voltage collapse and active losses of network IEEE 30 bus test. Therefore, we must choose among FACTS devices, those with specific applications such as maintaining the voltage at the desired value and the control of power flow, SVC is the most effective in the compensation of reactive as well as maintaining the voltage, and TCSC is the best choice for a proper control of power flow and consequently the reduction of active losses. The simulation results show clearly the effect of wind power plants and FACTS on the grid, voltage stability and power quality of electric power system.

  7. Next Generation Wind Turbine

    Energy Technology Data Exchange (ETDEWEB)

    Cheraghi, S. Hossein [Western New England Univ., Springfield, MA (United States); Madden, Frank [FloDesign Wind Turbine Corp., Waltham, MA (United States)

    2012-09-01

    The goal of this collaborative effort between Western New England University's College of Engineering and FloDesign Wind Turbine (FDWT) Corporation to wok on a novel areodynamic concept that could potentially lead to the next generation of wind turbines. Analytical studies and early scale model tests of FDWT's Mixer/Ejector Wind Turbine (MEWT) concept, which exploits jet-age advanced fluid dynamics, indicate that the concept has the potential to significantly reduce the cost of electricity over conventional Horizontal Axis Wind Turbines while reducing land usage. This project involved the design, fabrication, and wind tunnel testing of components of MEWT to provide the research and engineering data necessary to validate the design iterations and optimize system performance. Based on these tests, a scale model prototype called Briza was designed, fabricated, installed and tested on a portable tower to investigate and improve the design system in real world conditions. The results of these scale prototype efforts were very promising and have contributed significantly to FDWT's ongoing development of a product scale wind turbine for deployment in multiple locations around the U.S. This research was mutually beneficial to Western New England University, FDWT, and the DOE by utilizing over 30 student interns and a number of faculty in all efforts. It brought real-world wind turbine experience into the classroom to further enhance the Green Engineering Program at WNEU. It also provided on-the-job training to many students, improving their future employment opportunities, while also providing valuable information to further advance FDWT's mixer-ejector wind turbine technology, creating opportunities for future project innovation and job creation.

  8. Floating wind turbine system

    Science.gov (United States)

    Viterna, Larry A. (Inventor)

    2009-01-01

    A floating wind turbine system with a tower structure that includes at least one stability arm extending therefrom and that is anchored to the sea floor with a rotatable position retention device that facilitates deep water installations. Variable buoyancy for the wind turbine system is provided by buoyancy chambers that are integral to the tower itself as well as the stability arm. Pumps are included for adjusting the buoyancy as an aid in system transport, installation, repair and removal. The wind turbine rotor is located downwind of the tower structure to allow the wind turbine to follow the wind direction without an active yaw drive system. The support tower and stability arm structure is designed to balance tension in the tether with buoyancy, gravity and wind forces in such a way that the top of the support tower leans downwind, providing a large clearance between the support tower and the rotor blade tips. This large clearance facilitates the use of articulated rotor hubs to reduced damaging structural dynamic loads. Major components of the turbine can be assembled at the shore and transported to an offshore installation site.

  9. Wind turbines and idiopathic symptoms

    DEFF Research Database (Denmark)

    Blanes-Vidal, Victoria; Schwartz, Joel

    2016-01-01

    Whether or not wind turbines pose a risk to human health is a matter of heated debate. Personal reactions to other environmental exposures occurring in the same settings as wind turbines may be responsible of the reported symptoms. However, these have not been accounted for in previous studies. We...... investigated whether there is an association between residential proximity to wind turbines and idiopathic symptoms, after controlling for personal reactions to other environmental co-exposures. We assessed wind turbine exposures in 454 residences as the distance to the closest wind turbine (Dw) and number...... of wind turbines

  10. Wind turbine control and monitoring

    CERN Document Server

    Luo, Ningsu; Acho, Leonardo

    2014-01-01

    Maximizing reader insights into the latest technical developments and trends involving wind turbine control and monitoring, fault diagnosis, and wind power systems, 'Wind Turbine Control and Monitoring' presents an accessible and straightforward introduction to wind turbines, but also includes an in-depth analysis incorporating illustrations, tables and examples on how to use wind turbine modeling and simulation software.   Featuring analysis from leading experts and researchers in the field, the book provides new understanding, methodologies and algorithms of control and monitoring, comput

  11. 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...

  12. Unbalanced voltage faults: the impact on structural loads of doubly fed asynchronous generator wind turbines

    DEFF Research Database (Denmark)

    Barahona Garzón, Braulio; Cutululis, Nicolaos Antonio; Hansen, Anca Daniela

    2014-01-01

    , and control dynamics in an integrated simulation environment based on an aeroelastic code (HAWC2) and software for control design (Matlab/Simulink). In the present analysis, 1 Hz equivalent loads are used to compare fatigue loads, whereas maximum–minimum values are used to compare extreme loads. A control......This paper investigates the impact that unbalanced voltage faults have on wind turbine structural loads. In such cases, electromagnetic torque oscillations occur at two times the supply voltage frequency. The objectives of this work are to quantify wind turbine structural loads induced...... by unbalanced voltage faults relative to those during normal operation; and to evaluate the potential for reducing structural loads with the control of the generator. The method applied is integrated dynamic analysis. Namely, dynamic analysis with models that consider the most important aeroelastic, electrical...

  13. Wind turbine noise diagnostics

    International Nuclear Information System (INIS)

    Richarz, W.; Richarz, H.

    2009-01-01

    This presentation proposed a self-consistent model for broad-band noise emitted from modern wind turbines. The simple source model was consistent with the physics of sound generation and considered the unique features of wind turbines. Although the acoustics of wind turbines are similar to those of conventional propellers, the dimensions of wind turbines pose unique challenges in diagnosing noise emission. The general features of the sound field were deduced. Source motion and source directivity appear to be responsible for amplitude variations. The amplitude modulation is likely to make wind-turbine noise more audible, and may be partly responsible for annoyance that has been reported in the literature. Acoustic array data suggests that broad-band noise is emitted predominantly during the downward sweep of each rotor blade. Source motion and source directivity account for the observed pattern. Rotor-tower interaction effects are of lesser importance. Predicted amplitude modulation ranges from 1 dB to 6dB. 2 refs., 9 figs.

  14. Reliability Analysis of Wind Turbines

    DEFF Research Database (Denmark)

    Toft, Henrik Stensgaard; Sørensen, John Dalsgaard

    2008-01-01

    In order to minimise the total expected life-cycle costs of a wind turbine it is important to estimate the reliability level for all components in the wind turbine. This paper deals with reliability analysis for the tower and blades of onshore wind turbines placed in a wind farm. The limit states......) the reliability level for a wind turbine placed in a wind farm is considered, and wake effects from neighbouring wind turbines is taken into account. An illustrative example with calculation of the reliability for mudline bending of the tower is considered. In the example the design is determined according...

  15. Wind Turbines and Human Health

    Science.gov (United States)

    Knopper, Loren D.; Ollson, Christopher A.; McCallum, Lindsay C.; Whitfield Aslund, Melissa L.; Berger, Robert G.; Souweine, Kathleen; McDaniel, Mary

    2014-01-01

    The association between wind turbines and health effects is highly debated. Some argue that reported health effects are related to wind turbine operation [electromagnetic fields (EMF), shadow flicker, audible noise, low-frequency noise, infrasound]. Others suggest that when turbines are sited correctly, effects are more likely attributable to a number of subjective variables that result in an annoyed/stressed state. In this review, we provide a bibliographic-like summary and analysis of the science around this issue specifically in terms of noise (including audible, low-frequency noise, and infrasound), EMF, and shadow flicker. Now there are roughly 60 scientific peer-reviewed articles on this issue. The available scientific evidence suggests that EMF, shadow flicker, low-frequency noise, and infrasound from wind turbines are not likely to affect human health; some studies have found that audible noise from wind turbines can be annoying to some. Annoyance may be associated with some self-reported health effects (e.g., sleep disturbance) especially at sound pressure levels >40 dB(A). Because environmental noise above certain levels is a recognized factor in a number of health issues, siting restrictions have been implemented in many jurisdictions to limit noise exposure. These setbacks should help alleviate annoyance from noise. Subjective variables (attitudes and expectations) are also linked to annoyance and have the potential to facilitate other health complaints via the nocebo effect. Therefore, it is possible that a segment of the population may remain annoyed (or report other health impacts) even when noise limits are enforced. Based on the findings and scientific merit of the available studies, the weight of evidence suggests that when sited properly, wind turbines are not related to adverse health. Stemming from this review, we provide a number of recommended best practices for wind turbine development in the context of human health. PMID:24995266

  16. Wind turbines and human health.

    Science.gov (United States)

    Knopper, Loren D; Ollson, Christopher A; McCallum, Lindsay C; Whitfield Aslund, Melissa L; Berger, Robert G; Souweine, Kathleen; McDaniel, Mary

    2014-01-01

    The association between wind turbines and health effects is highly debated. Some argue that reported health effects are related to wind turbine operation [electromagnetic fields (EMF), shadow flicker, audible noise, low-frequency noise, infrasound]. Others suggest that when turbines are sited correctly, effects are more likely attributable to a number of subjective variables that result in an annoyed/stressed state. In this review, we provide a bibliographic-like summary and analysis of the science around this issue specifically in terms of noise (including audible, low-frequency noise, and infrasound), EMF, and shadow flicker. Now there are roughly 60 scientific peer-reviewed articles on this issue. The available scientific evidence suggests that EMF, shadow flicker, low-frequency noise, and infrasound from wind turbines are not likely to affect human health; some studies have found that audible noise from wind turbines can be annoying to some. Annoyance may be associated with some self-reported health effects (e.g., sleep disturbance) especially at sound pressure levels >40 dB(A). Because environmental noise above certain levels is a recognized factor in a number of health issues, siting restrictions have been implemented in many jurisdictions to limit noise exposure. These setbacks should help alleviate annoyance from noise. Subjective variables (attitudes and expectations) are also linked to annoyance and have the potential to facilitate other health complaints via the nocebo effect. Therefore, it is possible that a segment of the population may remain annoyed (or report other health impacts) even when noise limits are enforced. Based on the findings and scientific merit of the available studies, the weight of evidence suggests that when sited properly, wind turbines are not related to adverse health. Stemming from this review, we provide a number of recommended best practices for wind turbine development in the context of human health.

  17. Superconducting wind turbine generators

    DEFF Research Database (Denmark)

    Abrahamsen, Asger Bech; Mijatovic, Nenad; Seiler, Eugen

    2010-01-01

    We have examined the potential of 10 MW superconducting direct drive generators to enter the European offshore wind power market and estimated that the production of about 1200 superconducting turbines until 2030 would correspond to 10% of the EU offshore market. The expected properties of future...... offshore turbines of 8 and 10 MW have been determined from an up-scaling of an existing 5 MW turbine and the necessary properties of the superconducting drive train are discussed. We have found that the absence of the gear box is the main benefit and the reduced weight and size is secondary. However......, the main challenge of the superconducting direct drive technology is to prove that the reliability is superior to the alternative drive trains based on gearboxes or permanent magnets. A strategy of successive testing of superconducting direct drive trains in real wind turbines of 10 kW, 100 kW, 1 MW and 10...

  18. Wind turbines, is it just wind?

    International Nuclear Information System (INIS)

    Boiteux, M.

    2012-01-01

    The author first outlines that wind energy is not only random, but almost absent in extreme situations when it would be needed (for example and notably, very cold weather without wind). He suggests the association of a gas turbine to each wind turbine, so that the gas turbine will replace non operating wind turbines. He notices that wind turbines are not proximity energy as they were said to be, and that profitability in fact requires tens of grouped giant wind turbines. He also outlines the high cost of construction of grids for the connection of these wind turbines. Thus, he states that wind energy is far from being profitable in the present conditions of electricity tariffs in France

  19. Type IV Wind Turbine Model

    DEFF Research Database (Denmark)

    Hansen, Anca Daniela; Margaris, Ioannis D.

    (WPP) will be considered. The aggregate WPP model, which will be based on the upscaling of the individual wind turbine model on the electrical part, will make use of an equivalent wind speed. The implemented model follows the basic structure of the generic standard Type 4 wind turbine model proposed...... by the International Electrotechnical Commission (IEC), in the IEC61400-27-1 Committee Draft for electrical simulation models for wind power generation, which is currently under review, [1]. The Type 4 wind turbine model described in this report includes a set of adjustments of the standard Type 4 wind turbine model...... 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...

  20. Aerodynamics of wind turbines

    CERN Document Server

    Hansen, Martin O L

    2015-01-01

    Aerodynamics of Wind Turbines is the established essential text for the fundamental solutions to efficient wind turbine design. Now in its third edition, it has been substantially updated with respect to structural dynamics and control. The new control chapter now includes details on how to design a classical pitch and torque regulator to control rotational speed and power, while the section on structural dynamics has been extended with a simplified mechanical system explaining the phenomena of forward and backward whirling modes. Readers will also benefit from a new chapter on Vertical Axis W

  1. Offshore Wind Turbine Design

    DEFF Research Database (Denmark)

    Frandsen, Sten; Hansen, Erik Asp; Ibsen, Lars Bo

    2006-01-01

    Current offshore wind turbine design methods have matured to a 1st generation state, manifested in the draft of a possible standard, IEC 61400-3 (2005). It is now time to investigate the possibilities of improving existing methods. To do so in an efficient manner a clear identification of the most...... important uncertainty drivers specific for offshore wind turbine design loads is required. Describing the initial efforts in a Danish research project, the paper points to focal points for research and development. These are mainly: soil-structure interaction, improved modelling of wave loads from deep...

  2. Breaking wave impacts on offshore wind turbine foundations

    DEFF Research Database (Denmark)

    Bredmose, Henrik; Jacobsen, Niels Gjøl

    2010-01-01

    Extreme wave loads from breaking waves on a monopile foundation are computed within a 3D CFD model. The wave impacts are obtained by application of focused wave groups. For a fixed position of the monopile, the focus location of the wave group is varied to produce impacts with front shapes...... that for the impacts of spilling breakers the peak force gets smaller the more developed the breaking is. This is in qualitative agreement with a finding from shallow water impacts on vertical walls: the strongest wave loads are associated with breakers that hit the structure with slightly overturning front...

  3. Vertical Wave Impacts on Offshore Wind Turbine Inspection Platforms

    DEFF Research Database (Denmark)

    Bredmose, Henrik; Jacobsen, Niels Gjøl

    2011-01-01

    Breaking wave impacts on a monopile at 20 m depth are computed with a VOF (Volume Of Fluid) method. The impacting waves are generated by the second-order focused wave group technique, to obtain waves that break at the position of the monopile. The subsequent impact from the vertical run-up flow....... The dependence of the vertical platform load to the platform level is discussed. Attention is given to the significant downward force that occur after the upward force associated with the vertical impact. The effect of the numerical resolution on the results is assessed. The position of wave overturning is found...... to be influenced by the grid resolution. For the lowest platform levels, the vertical impact is found to contribute to the peak values of in-line force and overturning moment....

  4. On the Impact of information access delays on remote control of a wind turbine

    DEFF Research Database (Denmark)

    Madsen, Jacob Theilgaard; Barradas Berglind, Jose de Jesus; Madsen, Tatiana Kozlova

    2015-01-01

    It is important to reduce the impact of renewable production in the power grid by means of control, due to increased frequency deviations and imbalances caused by these assets. Cost efficient deployment of asset control frequently results in a distributed control architecture where the controller...... by the controller to gather sensor information and and quantitatively characterize the impact of these access strategies on the controller performance...... farm controller. The controller attempts to reduce fatigue on the wind turbine, which is used as a measure of the controller performance. Via simulation analysis, we show the degradation of the controller performance when subject to network delays. We analyse different access strategies useable...

  5. Wind conditions for wind turbine design

    Energy Technology Data Exchange (ETDEWEB)

    Maribo Pedersen, B.

    1999-04-01

    Delegates from Europe and USA attended the meeting and discussed general aspects of wind conditions for wind turbine design. The subjects and the presented papers covered a very broad range of aspects of wind conditions and related influence on the wind turbine. (EHS)

  6. Wind turbine reliability analysis

    OpenAIRE

    Pinar Pérez, Jesús María; García Márquez, Fausto Pedro; Tobias, Andrew Mark; Papaelias, Mayorkinos

    2013-01-01

    Against the background of steadily increasing wind power generation worldwide, wind turbine manufacturers are continuing to develop a range of configurations with different combinations of pitch control, rotor speeds, gearboxes, generators and converters. This paper categorizes the main designs, focusing on their reliability by bringing together and comparing data from a selection of major studies in the literature. These are not particularly consistent but plotting failure rates against hour...

  7. Tornado type wind turbines

    Science.gov (United States)

    Hsu, Cheng-Ting

    1984-01-01

    A tornado type wind turbine has a vertically disposed wind collecting tower with spaced apart inner and outer walls and a central bore. The upper end of the tower is open while the lower end of the structure is in communication with a wind intake chamber. An opening in the wind chamber is positioned over a turbine which is in driving communication with an electrical generator. An opening between the inner and outer walls at the lower end of the tower permits radially flowing air to enter the space between the inner and outer walls while a vertically disposed opening in the wind collecting tower permits tangentially flowing air to enter the central bore. A porous portion of the inner wall permits the radially flowing air to interact with the tangentially flowing air so as to create an intensified vortex flow which exits out of the top opening of the tower so as to create a low pressure core and thus draw air through the opening of the wind intake chamber so as to drive the turbine.

  8. Wind turbine spoiler

    Science.gov (United States)

    Sullivan, W.N.

    An aerodynamic spoiler system for a vertical axis wind turbine includes spoilers on the blades initially stored near the rotor axis to minimize drag. A solenoid latch adjacent the central support tower releases the spoilers and centrifugal force causes the spoilers to move up the turbine blades away from the rotor axis, thereby producing a braking effect and actual slowing of the associated wind turbine, if desired. The spoiler system can also be used as an infinitely variable power control by regulated movement of the spoilers on the blades over the range between the undeployed and fully deployed positions. This is done by the use of a suitable powered reel and cable located at the rotor tower to move the spoilers.

  9. Wind Turbine Blade

    DEFF Research Database (Denmark)

    2010-01-01

    The invention relates to a blade for a wind turbine, particularly to a blade that may be produced by an advanced manufacturing process for producing a blade with high quality structural components. Particularly, the structural components, which are preferably manufactured from fibre reinforced...

  10. SPATIALLY-EXPLICIT BAT IMPACT SCREENING TOOL FOR WIND TURBINE SITING

    Energy Technology Data Exchange (ETDEWEB)

    Versar, Inc.; Exponent, Inc.

    2013-10-28

    As the U.S. seeks to increase energy production from renewable energy sources, development of wind power resources continues to grow. One of the most important ecological issues restricting wind energy development, especially the siting of wind turbines, is the potential adverse effect on bats. High levels of bat fatality have been recorded at a number of wind energy facilities, especially in the eastern United States. The U.S. Department of Energy contracted with Versar, Inc., and Exponent to develop a spatially-explicit site screening tool to evaluate the mortality of bats resulting from interactions (collisions or barotrauma) with wind turbines. The resulting Bat Vulnerability Assessment Tool (BVAT) presented in this report integrates spatial information about turbine locations, bat habitat features, and bat behavior as it relates to possible interactions with turbines. A model demonstration was conducted that focuses on two bat species, the eastern red bat (Lasiurus borealis) and the Indiana bat (Myotis sodalis). The eastern red bat is a relatively common tree-roosting species that ranges broadly during migration in the Eastern U.S., whereas the Indiana bat is regional species that migrates between a summer range and cave hibernacula. Moreover, Indiana bats are listed as endangered, and so the impacts to this species are of particular interest. The model demonstration used conditions at the Mountaineer Wind Energy Center (MWEC), which consists of 44 wind turbines arranged in a linear array near Thomas, West Virginia (Tucker County), to illustrate model functions and not to represent actual or potential impacts of the facility. The turbines at MWEC are erected on the ridge of Backbone Mountain with a nacelle height of 70 meters and a collision area of 72 meters (blade height) or 4,071 meters square. The habitat surrounding the turbines is an Appalachian mixed mesophytic forest. Model sensitivity runs showed that bat mortality in the model was most sensitive to

  11. Antenna Gain Impact on UWB Wind Turbine Blade Deflection Sensing

    DEFF Research Database (Denmark)

    Zhang, Shuai; Franek, Ondrej; Byskov, Claus

    2018-01-01

    effective (or equivalent) isotropic radiated power (EIRP), an HG tip antenna inside a blade gives stronger direct pulse amplitudes and better pulse waveforms for accurate and reliable distance estimations than the LG. Moreover, the direct pulse with the HG antenna is also closer to the blade surface, which...... in free space have similar realized gain when allocated inside blades, so that the emission power for the HG and LG antennas in blades can be the same. The antenna gain impacts on time-domain pulse waveforms and power distributions around a blade are carefully investigated (with the tip antenna inside...... a blade). Higher antenna gain enlarges both direct pulse and multipath but in different levels. To verify the simulations, time-domain measurements are performed with a full 37-meter blade. Pulse waveforms and power delay profiles are measured. From all the studies, it follows that: with the similar...

  12. Dependency in State Transitions of Wind Turbines

    DEFF Research Database (Denmark)

    Herp, Jürgen; Ramezani, Mohammad Hossein; S. Nadimi, Esmaeil

    2017-01-01

    © 2017 IEEE. Turbine states and predicting the transition into failure states ahead of time is important in operation and maintenance of wind turbines. This study presents a method to monitor state transitions of a wind turbine based on the online inference on residuals. In a Bayesian framework...... the impact machine learning concepts have on the predictive performance of the presented models. In conclusion, a study on model residuals is performed to highlight the contribution to wind turbine monitoring. The presented algorithm can consistently detect the state transition under various configurations...

  13. Reliability Analysis of Wind Turbines

    DEFF Research Database (Denmark)

    Toft, Henrik Stensgaard; Sørensen, John Dalsgaard

    2008-01-01

    In order to minimise the total expected life-cycle costs of a wind turbine it is important to estimate the reliability level for all components in the wind turbine. This paper deals with reliability analysis for the tower and blades of onshore wind turbines placed in a wind farm. The limit states...... consideres are in the ultimate limit state (ULS) extreme conditions in the standstill position and extreme conditions during operating. For wind turbines, where the magnitude of the loads is influenced by the control system, the ultimate limit state can occur in both cases. In the fatigue limit state (FLS......) the reliability level for a wind turbine placed in a wind farm is considered, and wake effects from neighbouring wind turbines is taken into account. An illustrative example with calculation of the reliability for mudline bending of the tower is considered. In the example the design is determined according...

  14. Great expectations: large wind turbines

    International Nuclear Information System (INIS)

    De Vries, E.

    2001-01-01

    This article focuses on wind turbine product development, and traces the background to wind turbines from the first generation 1.5 MW machines in 1995-6, plans for the second generation 3-5 MW class turbines to meet the expected boom in offshore wind projects, to the anticipated installation of a 4.5 MW turbine, and offshore wind projects planned for 2000-2002. The switch by the market leader Vestas to variable speed operation in 2000, the new product development and marketing strategy taken by the German Pro + Pro consultancy in their design of a 1.5 MW variable speed pitch control concept, the possible limiting of the size of turbines due to logistical difficulties, opportunities offered by air ships for large turbines, and the commissioning of offshore wind farms are discussed. Details of some 2-5 MW offshore wind turbine design specifications are tabulated

  15. Impact of fault ride-through requirements on fixed-speed wind turbine structural loads

    DEFF Research Database (Denmark)

    Hansen, Anca Daniela; Cutululis, Nicolaos Antonio; Markou, Helen

    2011-01-01

    simulation tools, which have expertise in different specialized wind turbines design areas. Two complimentary simulation tools are considered i.e. the detailed power system simulation tool PowerFactory from DIgSILENT and the advanced aeroelastic computer code HAWC2, in order to assess of the dynamic response...... by performing a rainflow and a statistical analysis for fatigue and ultimate structural loads, respectively. Two cases are compared i.e. one where the turbine is immediately disconnected from the grid when a grid fault occurs and one where the turbine is equipped with a fault ride-through controller...... faults. This article proposes a computer approach for the quantification of the wind turbines structural loads caused by the fault ride-through grid requirements. This approach, exemplified for the case of a 2MW active stall wind turbine, relies on the combination of knowledge from complimentary...

  16. Aeroservoelasticity of wind turbines

    Energy Technology Data Exchange (ETDEWEB)

    Skovmose Kallesoee, B.

    2007-12-14

    This thesis deals with the fundamental aeroelastic interaction between structural motion, Pitch action and control for a wind turbine blade. As wind turbines become larger, the interaction between pitch action, blade motion, aerodynamic forces, and control become even more important to understand and address. The main contribution of this thesis is the development of an aeroelastic blade model which on the one hand includes the important effects of steady state blade deformation, gravity and pitch action, and on the other it is transparent, suitable for analytical analysis and parameter studies, and furthermore linear and therefore suitable for control design. The development of the primary aeroelastic blade model is divided into four steps: 1) Nonlinear partial differential equations (PDEs) of structural blade motion are derived together with equations of pitch action and rotor speed; the individual terms in these equations are discussed and given physical interpretations; 2) Steady state blade deformation and induced velocities are computed by combining the PDEs with a steady state aerodynamic model; 3) Aeroelastic modes of motion are computed by combining the linearized PDEs with a linear unsteady aerodynamic model; this model is used to analyze how blade deformation effects the modes of motion; and 4) the linear aeroelastic blade model is derived by a modal expansion of the linearized PDEs combined with a linear unsteady aerodynamic model. The aeroelastic blade model has many similarities to a 2D blade section model, and it can be used instead of this in many applications, giving a transparent connection to a real wind turbine blade. In this work the aeroelastic blade model is used to analyze interaction between pitch action, blade motion and wind speed variations. Furthermore the model is used to develop a state estimator for estimating the wind speed and wind shear, and to suggest a load reducing controller. The state estimator estimates the wind shear very

  17. Small Wind Turbine Technology Assessment

    International Nuclear Information System (INIS)

    Avia Aranda, F.; Cruz Cruz, I.

    1999-01-01

    The result of the study carried out under the scope of the ATYCA project Test Plant of Wind Systems for Isolated Applications, about the state of art of the small wind turbine technology (wind turbines with swept area smaller than 40 m 2 ) is presented. The study analyzes the collected information on 60 models of wind turbines from 23 manufacturers in the worldwide market. Data from Chinese manufacturers, that have a large participation in the total number of small wind turbines in operation, are not included, due to the unavailability of the technical information. (Author) 15 refs

  18. Modeling of wind turbines for power system studies

    Energy Technology Data Exchange (ETDEWEB)

    Petru, T.

    2001-05-01

    When wind turbines are installed into the electric grid, the power quality is affected. Today, strict installation recommendations often prevail due to a lack of knowledge on this subject. Consequently, it is important to predict the impact of wind turbines on the electric grid before the turbines are installed. The thesis describes relevant power quality issues, discusses different configurations of wind turbines with respect to power quality and draw requirements regarding wind turbine modeling. A model of a stall-regulated, fixed-speed wind turbine system is introduced and its power quality impact on the electric grid is evaluated. The model is verified with field measurements.

  19. Superconducting wind turbine generators

    DEFF Research Database (Denmark)

    Mijatovic, Nenad

    in this thesis is a part of a larger endeavor, the Superwind project that focused on identifying the potentials that HTS machines could offer to the wind industry and addressing some of the challenges in the process. In order to identify these challenges, I have designed and constructed an HTS machine......A HTS machine could be a way to address some of the technical barriers offshore wind energy is about to face. Due to the superior power density of HTS machines, this technology could become a milestone on which many, including the wind industry, will rely on in the future. The work presented...... experimental setup which is made to serve as precursor, leading towards an optimized HTS machine concept proposed for wind turbines. In part, the work presented in this thesis will focus on the description of the experimental setup and reasoning behind the choices made during the design. The setup comprises...

  20. Wind Turbine Providing Grid Support

    DEFF Research Database (Denmark)

    2011-01-01

    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...... 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...

  1. Mitigating the negative impacts of tall wind turbines on bats: Vertical activity profiles and relationships to wind speed.

    Science.gov (United States)

    Wellig, Sascha D; Nusslé, Sébastien; Miltner, Daniela; Kohle, Oliver; Glaizot, Olivier; Braunisch, Veronika; Obrist, Martin K; Arlettaz, Raphaël

    2018-01-01

    Wind turbines represent a source of hazard for bats, especially through collision with rotor blades. With increasing technical development, tall turbines (rotor-swept zone 50-150 m above ground level) are becoming widespread, yet we lack quantitative information about species active at these heights, which impedes proposing targeted mitigation recommendations for bat-friendly turbine operation. We investigated vertical activity profiles of a bat assemblage, and their relationships to wind speed, within a major valley of the European Alps where tall wind turbines are being deployed. To monitor bat activity we installed automatic recorders at sequentially increasing heights from ground level up to 65 m, with the goal to determine species-specific vertical activity profiles and to link them to wind speed. Bat call sequences were analysed with an automatic algorithm, paying particular attention to mouse-eared bats (Myotis myotis and Myotis blythii) and the European free-tailed bat (Tadarida teniotis), three locally rare species. The most often recorded bats were the Common pipistrelle (Pipistrellus pipistrellus) and Savi's pipistrelle (Hypsugo savii). Mouse-eared bats were rarely recorded, and mostly just above ground, appearing out of risk of collision. T. teniotis had a more evenly distributed vertical activity profile, often being active at rotor level, but its activity at that height ceased above 5 ms-1 wind speed. Overall bat activity in the rotor-swept zone declined with increasing wind speed, dropping below 5% above 5.4 ms-1. Collision risk could be drastically reduced if nocturnal operation of tall wind turbines would be restricted to wind speeds above 5 ms-1. Such measure should be implemented year-round because T. teniotis remains active in winter. This operational restriction is likely to cause only small energy production losses at these tall wind turbines, although further analyses are needed to assess these losses precisely.

  2. Controls of Hydraulic Wind Turbine

    OpenAIRE

    Zhang Yin; Kong Xiangdong; Hao Li; Ai Chao

    2016-01-01

    In this paper a hydraulic wind turbine generator system was proposed based on analysis the current wind turbines technologies. The construction and principles were introduced. The mathematical model was verified using MATLAB and AMsim. A displacement closed loop of swash plate of motor and a speed closed loop of generator were setup, a PID control is introduced to maintain a constant speed and fixed frequency at wind turbine generator. Simulation and experiment demonstrated that the system ca...

  3. Wind Turbine Radar Cross Section

    Directory of Open Access Journals (Sweden)

    David Jenn

    2012-01-01

    Full Text Available The radar cross section (RCS of a wind turbine is a figure of merit for assessing its effect on the performance of electronic systems. In this paper, the fundamental equations for estimating the wind turbine clutter signal in radar and communication systems are presented. Methods of RCS prediction are summarized, citing their advantages and disadvantages. Bistatic and monostatic RCS patterns for two wind turbine configurations, a horizontal axis three-blade design and a vertical axis helical design, are shown. The unique electromagnetic scattering features, the effect of materials, and methods of mitigating wind turbine clutter are also discussed.

  4. Controls of Hydraulic Wind Turbine

    Directory of Open Access Journals (Sweden)

    Zhang Yin

    2016-01-01

    Full Text Available In this paper a hydraulic wind turbine generator system was proposed based on analysis the current wind turbines technologies. The construction and principles were introduced. The mathematical model was verified using MATLAB and AMsim. A displacement closed loop of swash plate of motor and a speed closed loop of generator were setup, a PID control is introduced to maintain a constant speed and fixed frequency at wind turbine generator. Simulation and experiment demonstrated that the system can connect grid to generate electric and enhance reliability. The control system demonstrates a high performance speed regulation and effectiveness. The results are great significant to design a new type hydraulic wind turbine system.

  5. Numerical assessment of wind turbine blade damage due to contact/impact with tower during installation

    Science.gov (United States)

    Shankar Verma, Amrit; Petter Vedvik, Nils; Gao, Zhen

    2017-12-01

    The use of floating crane vessel for installation of offshore wind turbine blades presents a great challenge in terms of its random motions and is likely to increase the probability of the blade hitting the preassembled tower during lifting operation. To evaluate the consequences of such scenarios and to determine the allowable motions or sea states for such operations, it is very important to understand the damage development in the blade due to impact. The present paper employs the application of high fidelity finite element method to investigate the damage behavior in the blade when the leading edge of the blade hits the tower. A nonlinear time domain structural analysis using ABAQUS was conducted on the DTU 10 MW reference blade model which is based on shell elements. Damage assessment along with the nature of evolution of various energies is examined and presented for two different impact velocities with modified layup stacking sequence at the contact region.

  6. Impact of wind turbine sound on annoyance, self-reported sleep disturbance and psychological distress

    NARCIS (Netherlands)

    Bakker, R.H.; Pedersen, E.; Berg, G.P. van den; Stewart, R.E.; Lok, W.; Bouma, J.

    2012-01-01

    Purpose of the research: The present government in the Netherlands intends to realize a substantial growth of wind energy before 2020, both onshore and offshore. Wind turbines, when positioned in the neighborhood of residents may cause visual annoyance and noise annoyance. Studies on other

  7. Breaking wave impact forces on truss support structures for offshore wind turbines

    Science.gov (United States)

    Cieślikiewicz, Witold; Gudmestad, Ove T.; Podrażka, Olga

    2014-05-01

    Due to depletion of the conventional energy sources, wind energy is becoming more popular these days. Wind energy is being produced mostly from onshore farms, but there is a clear tendency to transfer wind farms to the sea. The foundations of offshore wind turbines may be truss structures and might be located in shallow water, where are subjected to highly varying hydrodynamic loads, particularly from plunging breaking waves. There are models for impact forces prediction on monopiles. Typically the total wave force on slender pile from breaking waves is a superposition of slowly varying quasi-static force, calculated from the Morison equation and additional dynamical, short duration force due to the impact of the breaker front or breaker tongue. There is not much research done on the truss structures of wind turbines and there are still uncertainties on slamming wave forces, due to plunging breaking waves on those structures. Within the WaveSlam (Wave slamming forces on truss structures in shallow water) project the large scale tests were carried out in 2013 at the Large Wave Flume in Forschungszentrum Küste (FZK) in Hannover, Germany. The following institutions participated in this initiative: the University of Stavanger and the Norwegian University of Science and Technology (project management), University of Gdańsk, Poland, Hamburg University of Technology and the University of Rostock, Germany and Reinertsen AS, Norway. This work was supported by the EU 7th Framework Programme through the grant to the budget of the Integrating Activity HYDRALAB IV. The main aim of the experiment was to investigate the wave slamming forces on truss structures, development of new and improvement of existing methods to calculate forces from the plunging breakers. The majority of the measurements were carried out for regular waves with specified frequencies and wave heights as well as for the irregular waves based on JONSWAP spectrum. The truss structure was equipped with both

  8. Probabilistic Design of Wind Turbines

    DEFF Research Database (Denmark)

    Toft, Henrik Stensgaard

    During the last decades, wind turbines have been continuously developed with the aim of maximizing the life cycle benefits (production of electricity) minus the costs of planning, materials, installation, operation & maintenance as well as possible failure. In order to continue this development...... turbines and the central topics considered are statistical load extrapolation of extreme loads during operation and reliability assessment of wind turbine blades. Wind turbines differ from most civil engineering structures by having a control system which highly influences the loading. In the literature......, methods for estimating the extreme load-effects on a wind turbine during operation, where the control system is active, have been proposed. But these methods and thereby the estimated loads are often subjected to a significant uncertainty which influences the reliability of the wind turbine...

  9. An open source GIS tool to quantify the visual impact of wind turbines and photovoltaic panels

    International Nuclear Information System (INIS)

    Minelli, Annalisa; Marchesini, Ivan; Taylor, Faith E.; De Rosa, Pierluigi; Casagrande, Luca; Cenci, Michele

    2014-01-01

    Although there are clear economic and environmental incentives for producing energy from solar and wind power, there can be local opposition to their installation due to their impact upon the landscape. To date, no international guidelines exist to guide quantitative visual impact assessment of these facilities, making the planning process somewhat subjective. In this paper we demonstrate the development of a method and an Open Source GIS tool to quantitatively assess the visual impact of these facilities using line-of-site techniques. The methods here build upon previous studies by (i) more accurately representing the shape of energy producing facilities, (ii) taking into account the distortion of the perceived shape and size of facilities caused by the location of the observer, (iii) calculating the possible obscuring of facilities caused by terrain morphology and (iv) allowing the combination of various facilities to more accurately represent the landscape. The tool has been applied to real and synthetic case studies and compared to recently published results from other models, and demonstrates an improvement in accuracy of the calculated visual impact of facilities. The tool is named r.wind.sun and is freely available from GRASS GIS AddOns. - Highlights: • We develop a tool to quantify wind turbine and photovoltaic panel visual impact. • The tool is freely available to download and edit as a module of GRASS GIS. • The tool takes into account visual distortion of the shape and size of objects. • The accuracy of calculation of visual impact is improved over previous methods

  10. An open source GIS tool to quantify the visual impact of wind turbines and photovoltaic panels

    Energy Technology Data Exchange (ETDEWEB)

    Minelli, Annalisa, E-mail: Annalisa.Minelli@univ-brest.fr [Insitute Universitaire Européen de la Mer, Université de la Bretagne Occidentale, Rue Dumont D' Urville, 29280 Plouzané (France); Marchesini, Ivan, E-mail: Ivan.Marchesini@irpi.cnr.it [National Research Council (CNR), Research Insitute for Geo-hydrological Protection (IRPI), Strada della Madonna Alta 126, 06125 Perugia (Italy); Taylor, Faith E., E-mail: Faith.Taylor@kcl.ac.uk [Earth and Environmental Dynamics Research Group, Department of Geography, King' s College London, Strand, London WC2R 2LS (United Kingdom); De Rosa, Pierluigi, E-mail: Pierluigi.Derosa@unipg.it [Physics and Geology Department, University of Perugia, Via Zefferino Faina 4, 06123 Perugia (Italy); Casagrande, Luca, E-mail: Luca.Casagrande@gfosservices.it [Gfosservices S.A., Open Source GIS-WebGIS Solutions, Spatial Data Infrastructures, Planning and Counseling, Via F.lli Cairoli 24, 06127 Perugia (Italy); Cenci, Michele, E-mail: mcenci@regione.umbria.it [Servizio Energia qualità dell' ambiente, rifiuti, attività estrattive, Regione Umbia, Corso Vannucci 96, 06121 Perugia (Italy)

    2014-11-15

    Although there are clear economic and environmental incentives for producing energy from solar and wind power, there can be local opposition to their installation due to their impact upon the landscape. To date, no international guidelines exist to guide quantitative visual impact assessment of these facilities, making the planning process somewhat subjective. In this paper we demonstrate the development of a method and an Open Source GIS tool to quantitatively assess the visual impact of these facilities using line-of-site techniques. The methods here build upon previous studies by (i) more accurately representing the shape of energy producing facilities, (ii) taking into account the distortion of the perceived shape and size of facilities caused by the location of the observer, (iii) calculating the possible obscuring of facilities caused by terrain morphology and (iv) allowing the combination of various facilities to more accurately represent the landscape. The tool has been applied to real and synthetic case studies and compared to recently published results from other models, and demonstrates an improvement in accuracy of the calculated visual impact of facilities. The tool is named r.wind.sun and is freely available from GRASS GIS AddOns. - Highlights: • We develop a tool to quantify wind turbine and photovoltaic panel visual impact. • The tool is freely available to download and edit as a module of GRASS GIS. • The tool takes into account visual distortion of the shape and size of objects. • The accuracy of calculation of visual impact is improved over previous methods.

  11. Reliability Modeling of Wind Turbines

    DEFF Research Database (Denmark)

    Kostandyan, Erik

    Cost reductions for offshore wind turbines are a substantial requirement in order to make offshore wind energy more competitive compared to other energy supply methods. During the 20 – 25 years of wind turbines useful life, Operation & Maintenance costs are typically estimated to be a quarter...... the actions should be made and the type of actions requires knowledge on the accumulated damage or degradation state of the wind turbine components. For offshore wind turbines, the action times could be extended due to weather restrictions and result in damage or degradation increase of the remaining...... for Operation & Maintenance planning. Concentrating efforts on development of such models, this research is focused on reliability modeling of Wind Turbine critical subsystems (especially the power converter system). For reliability assessment of these components, structural reliability methods are applied...

  12. Reliability assessment of Wind turbines

    DEFF Research Database (Denmark)

    Sørensen, John Dalsgaard

    2015-01-01

    Wind turbines can be considered as structures that are in between civil engineering structures and machines since they consist of structural components and many electrical and machine components together with a control system. Further, a wind turbine is not a one-of-a-kind structure...... but manufactured in series production based on many component tests, some prototype tests and zeroseries wind turbines. These characteristics influence the reliability assessment where focus in this paper is on the structural components. Levelized Cost Of Energy is very important for wind energy, especially when...... comparing to other energy sources. Therefore much focus is on cost reductions and improved reliability both for offshore and onshore wind turbines. The wind turbine components should be designed to have sufficient reliability level with respect to both extreme and fatigue loads but also not be too costly...

  13. 75 FR 27583 - Job Corps: Final Finding of No Significant Impact (FONSI) for Small Vertical Wind Turbine and...

    Science.gov (United States)

    2010-05-17

    ... DEPARTMENT OF LABOR Office of the Secretary Job Corps: Final Finding of No Significant Impact (FONSI) for Small Vertical Wind Turbine and Solar Installation at the Paul Simon Job Corps Center Located... and solar cells at the Paul Simon Job Corps [[Page 27584

  14. Serially-Connected Compensator for Eliminating the Unbalanced Three-Phase Voltage Impact on Wind Turbine Generators: Preprint

    Energy Technology Data Exchange (ETDEWEB)

    Wu, Z.; Hsu, P.; Muljadi, E.; Gao, W.

    2015-04-06

    Untransposed transmission lines, unbalanced tap changer operations, and unbalanced loading in weak distribution lines can cause unbalanced-voltage conditions. The resulting unbalanced voltage at the point of interconnection affects proper gird integration and reduces the lifetime of wind turbines due to power oscillations, torque pulsations, mechanical stresses, energy losses, and uneven and overheating of the generator stator winding. This work investigates the dynamic impact of unbalanced voltage on the mechanical and electrical components of integrated Fatigue, Aerodynamics, Structures, and Turbulence (FAST) wind turbine generation systems (WTGs) of Type 1 (squirrel-cage induction generator) and Type 3 (doubly-fed induction generator). To alleviate this impact, a serially-connected compensator for a three-phase power line is proposed to balance the wind turbine-side voltage. Dynamic simulation studies are conducted in MATLAB/Simulink to compare the responses of these two types of wind turbine models under normal and unbalanced-voltage operation conditions and demonstrate the effectiveness of the proposed compensator.

  15. Wind turbine airfoil catalogue

    DEFF Research Database (Denmark)

    Bertagnolio, F.; Sørensen, Niels N.; Johansen, Jeppe

    2001-01-01

    The aim of this work is two-sided. Firstly, experimental results obtained for numerous sets of airfoil measurements (mainly intended for wind turbine applications) are collected and compared with computational results from the 2D Navier-Stokes solverEllipSys2D, as well as results from the panel...... data. A study correlating the available data and this classification is performed. It is found that transition modelling is to a large extent responsible forthe poor quality of the computational results for most of the considered airfoils. The transition model mechanism that leads...

  16. Wind turbine airfoil catalogue

    OpenAIRE

    Bertagnolio, F.; Sørensen, Niels N.; Johansen, Jeppe; Fuglsang, P.

    2001-01-01

    The aim of this work is two-sided. Firstly, experimental results obtained for numerous sets of airfoil measurements (mainly intended for wind turbine applications) are collected and compared with computational results from the 2D Navier-Stokes solverEllipSys2D, as well as results from the panel method code XFOIL. Secondly, we are interested in validating the code EllipSys2D and finding out for which airfoils it does not perform well compared to the experiments, as well as why, when it does so...

  17. Impact of wind turbine sound on annoyance, self-reported sleep disturbance and psychological distress.

    Science.gov (United States)

    Bakker, R H; Pedersen, E; van den Berg, G P; Stewart, R E; Lok, W; Bouma, J

    2012-05-15

    The present government in the Netherlands intends to realize a substantial growth of wind energy before 2020, both onshore and offshore. Wind turbines, when positioned in the neighborhood of residents may cause visual annoyance and noise annoyance. Studies on other environmental sound sources, such as railway, road traffic, industry and aircraft noise show that (long-term) exposure to sound can have negative effects other than annoyance from noise. This study aims to elucidate the relation between exposure to the sound of wind turbines and annoyance, self-reported sleep disturbance and psychological distress of people that live in their vicinity. Data were gathered by questionnaire that was sent by mail to a representative sample of residents of the Netherlands living in the vicinity of wind turbines A dose-response relationship was found between immission levels of wind turbine sound and selfreported noise annoyance. Sound exposure was also related to sleep disturbance and psychological distress among those who reported that they could hear the sound, however not directly but with noise annoyance acting as a mediator. Respondents living in areas with other background sounds were less affected than respondents in quiet areas. People living in the vicinity of wind turbines are at risk of being annoyed by the noise, an adverse effect in itself. Noise annoyance in turn could lead to sleep disturbance and psychological distress. No direct effects of wind turbine noise on sleep disturbance or psychological stress has been demonstrated, which means that residents, who do not hear the sound, or do not feel disturbed, are not adversely affected. Copyright © 2012 Elsevier B.V. All rights reserved.

  18. Reliability Modeling of Wind Turbines

    DEFF Research Database (Denmark)

    Kostandyan, Erik

    the actions should be made and the type of actions requires knowledge on the accumulated damage or degradation state of the wind turbine components. For offshore wind turbines, the action times could be extended due to weather restrictions and result in damage or degradation increase of the remaining...

  19. Impact of Penetration Wind Turbines on Transient Stability in Sulbagsel Electrical Interconnection System

    Science.gov (United States)

    Nurtrimarini Karim, Andi; Mawar Said, Sri; Chaerah Gunadin, Indar; Darusman B, Mustadir

    2018-03-01

    This paper presents a rotor angle analysis when transient disturbance occurs when wind turbines enter the southern Sulawesi electrical interconnection system (Sulbagsel) both without and with the addition of a Power Stabilizer (PSS) control device. Time domain simulation (TDS) method is used to analyze the rotor angle deviation (δ) and rotor angle velocity (ω). A total of 44 buses, 47 lines, 6 transformers, 15 generators and 34 loads were modeled for analysis after the inclusion of large-scale wind turbines in the Sidrap and Jeneponto areas. The simulation and computation results show the addition of PSS devices to the system when transient disturbance occurs when the winds turbine entering the Sulbagsel electrical system is able to dampen and improve the rotor angle deviation (δ) and the rotor angle velocity (ω) towards better thus helping the system to continue operation at a new equilibrium point.

  20. Sanitary impacts generated by wind turbines. situation of the wind sector. Proposition for the implementation of the setting-up procedure

    International Nuclear Information System (INIS)

    2008-01-01

    The National Academy of Medicine has evaluated the effects on health of wind turbines. This report recommends that the wind turbine construction is at a minimal distance of 1500 m for wind turbines having a power superior to 2.5 MW. The French agency of sanitary safety of environment and work (A.F.S.S.E.T.) is in charge by the Ministry of Health and Environment to evaluate the relevance of this distance recommendation. The work group recommends the implementation of a specifications text of the environmental impact study as well as a compulsory administrative check of the study. It is more particularly a question of: Defining a perimeter of study: indicate all the zones susceptible to be concerned by the noise of wind turbines, even those which are not inhabited; calculating the durations of impact of concerned zones, according to the predictable weather conditions over the year; indicating the measures taken by the developer of the wind farm in case of overtaking of the authorized emergence; the impact studies of the other projects have to take into account a possible incidence in the zones of impact of the wind farm; a cartography of the zones of impact of a wind site must be available in town hall. A particular attention must be attached to the duration and to the representativeness of the study of the existing situation. The method of appreciation of the sound level impact on the environment must be improved, what passes by a deepening of the knowledge in criterion of embarrassment due to the noise, of existence of threshold, spectral validity, validity according to the exposure time. The search for the simplicity in statutory subject should lead to engage efforts of clarification as regards the nuisances criteria. (N.C.)

  1. Impact of high level penetration of Wind Turbines on Power System Transient Stability

    DEFF Research Database (Denmark)

    Kalogiannis, Theodoros; Llano, Enrique Muller; Hoseinzadeh, Bakhtyar

    2015-01-01

    One of the most relevant aspects in power systems is their reliability and robustness of maintaining the stability under large disturbances. System stability is a crucial aspect to consider when expanding the network, e.g. while increasing the levels of wind power penetration. Wind turbine...... generators differ from the conventional ones in their inertial contribution to the grid, therefore, in most cases the ability of the system to maintain a stable operation is declined. To investigate this, two standard models are designed in PowerFactory software. The first is used to characterize system...... components, the response of the wind turbines and thereupon to validate them, whereas the second is used to estimate the maximum levels of wind power penetration. Those levels mainly depend on the spinning reserve, the inertia of the system and the severity of the event. Rate of change of frequency...

  2. Impact of the Converter Control Strategies on the Drive Train of Wind Turbine during Voltage Dips

    Directory of Open Access Journals (Sweden)

    Fenglin Miao

    2015-10-01

    Full Text Available The impact of converter control strategies on the drive train of wind turbines during voltage dips is investigated in this paper using a full electromechanical model. Aerodynamics and tower vibration are taken into consideration by means of a simulation program, named FAST. Detailed gearbox and electrical subsystems are represented in MATLAB. The dynamic response of electromagnetic torque and its impact on the mechanical variables are the concern in this paper and the response of electrical variables is less discussed. From the mechanical aspects, the effect of rising power recovery speed and unsymmetrical voltage dips are analyzed on the basis of the dynamic response of the high-speed shaft (HSS. A comparison of the impact on the drive train is made for two converter control strategies during small voltage dips. Through the analysis of torque, speed and tower vibration, the results indicate that both power recovery speed and the sudden torque sag have a significant impact on drive trains, and the effects depend on the different control strategies. Moreover, resonance might be excited on the drive train by an unbalanced voltage.

  3. Reliability of wind turbine blades: An overview of materials testing

    DEFF Research Database (Denmark)

    Holmes, John W.; Sørensen, Bent F.; Brøndsted, Povl

    2007-01-01

    The structural reliability of wind turbine components can have a profound impact on both the profitability and reputation of a wind turbine manufacturer or supplier of wind turbine components. The issue of reliability is of critical concern when large wind farm co-operatives are considered......, and when wind turbines are located in remote regions where the cost of inspections and repairs can be very high. From a structural viewpoint, wind turbine blades are subjected to very complex loading histories with coupled deformation modes. The long-term reliability of wind turbine blades requires...... an understanding of how damage develops in composite structures, composite materials and adhesives. Designing reliable wind turbine blades also requires the further development of laboratory scale and full scale test methods to evaluate the structural response and durability of new materials under various loading...

  4. Megawatt wind turbines gaining momentum

    International Nuclear Information System (INIS)

    Oehlenschlaeger, K.; Madsen, B.T.

    1996-01-01

    Through the short history of the modern wind turbine, electric utilities have made it amply clear that they have held a preference for large scale wind turbines over smaller ones, which is why wind turbine builders through the years have made numerous attempts develop such machines - machines that would meet the technical, aesthetic and economic demands that a customer would require. Considerable effort was put into developing such wind turbines in the early 1980s. There was the U.S. Department of Energy's MOD 1-5 program, which ranged up to 3.2 MW, Denmark's Nibe A and B, 630 kW turbine and the 2 MW Tjaereborg machine, Sweden's Naesudden, 3 MW, and Germany's Growian, 3 MW. Most of these were dismal failures, though some did show the potential of MW technology. (au)

  5. Assessment of wind turbines impact on landscape character and landscape planning

    Czech Academy of Sciences Publication Activity Database

    Cetkovský, Stanislav; Nováková, Eva

    2009-01-01

    Roč. 17, č. 2 (2009), s. 28-34 ISSN 1210-8812 Institutional research plan: CEZ:AV0Z30860518 Keywords : landscape character * wind turbines * landscape planning * GIS * visualisation * Czech Republic Subject RIV: DE - Earth Magnetism, Geodesy, Geography http://www.scopus.com/record/display.url?eid=2-s2.0-70449368205&origin

  6. Aerodynamics of wind turbines emerging topics

    CERN Document Server

    Amano, R S

    2014-01-01

    Focusing on Aerodynamics of Wind Turbines with topics ranging from Fundamental to Application of horizontal axis wind turbines, this book presents advanced topics including: Basic Theory for Wind turbine Blade Aerodynamics, Computational Methods, and Special Structural Reinforcement Technique for Wind Turbine Blades.

  7. Impact of wind turbine sound on general health, sleep disturbance and annoyance of workers: a pilot- study in Manjil wind farm, Iran.

    Science.gov (United States)

    Abbasi, Milad; Monazzam, Mohammad Reza; Akbarzadeh, Arash; Zakerian, Seyyed Abolfazl; Ebrahimi, Mohammad Hossein

    2015-01-01

    The wind turbine's sound seems to have a proportional effect on health of people living near to wind farms. This study aimed to investigate the effect of noise emitted from wind turbines on general health, sleep and annoyance among workers of manjil wind farm, Iran. A total number of 53 workers took part in this study. Based on the type of job, they were categorized into three groups of maintenance, security and office staff. The persons' exposure at each job-related group was measured by eight-hour equivalent sound level (LAeq, 8 h). A Noise annoyance scale, Epworth sleepiness scale and 28-item general health questionnaire was used for gathering data from workers. The data were analyzed through Multivariate Analysis of variance (MANOVA) test, Pillai's Trace test, Paired comparisons analysis and Multivariate regression test were used in the R software. The results showed that, response variables (annoyance, sleep disturbance and health) were significantly different between job groups. The results also indicated that sleep disturbance as well as noise exposure had a significant effect on general health. Noise annoyance and distance from wind turbines could significantly explain about 44.5 and 34.2 % of the variance in sleep disturbance and worker's general health, respectively. General health was significantly different in different age groups while age had no significant impact on sleep disturbance. The results were reverse for distance because it had no significant impact on health, but sleep disturbance was significantly affected. We came to this conclusion that wind turbines noise can directly impact on annoyance, sleep and health. This type of energy generation can have potential health risks for wind farm workers. However, further research is needed to confirm the results of this study.

  8. Technical information on the assessment of the potential impact of wind turbines on radio communication, radar and seismoacoustic systems

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2007-04-15

    Wind turbines can negatively impact radio, telecommunications, radar, or seismoacoustic systems when located within a certain distance. Early consultation with stakeholders is needed to ensure that installations do not interfere with existing systems. This document was prepared on behalf of the Radio Advisory Board to facilitate effective cohabitation between wind energy and existing systems through the early and effective sharing of information. Wind project proponents must develop a map showing the location of the proposed wind farm and all turbines as well as to determine potential impacts on radio, radar, or telecommunications systems in the area. Wind project proponents should then contact the applicable authority to determine if further investigation is warranted. Proponents and authorities must then undertake the necessary studies and measures to resolve the issues. This study focused on the development of a series of analytical methodologies and thresholds for identifying where and when potential inferences may occur. Negative impacts included shadowing; mirror-type reflections; and scattering. Impacts on radar systems, and seismoacoustic systems were considered. Consultation zone calculations were presented. 17 refs., 2 tabs., 4 figs.

  9. Operation Design of Wind Turbines in Strong Wind Conditions

    DEFF Research Database (Denmark)

    Shen, Wen Zhong; Montes, Melissa Barroso; Odgaard, Peter Fogh

    2012-01-01

    and variable speed pitch regulated wind turbines. The variable speed design is more suitable for wind turbines to run at very high wind speeds which can help the turbine braking system to stop the turbine at the new "cut-out" wind speed. Reference power, rotational speed and pitch angle have been designed...

  10. Active control: Wind turbine model

    DEFF Research Database (Denmark)

    Bindner, H.

    1999-01-01

    This report is a part of the reporting of the work done in the project 'Active Control of Wind Turbines'. This project aim is to develop a simulation model for design of control systems for turbines with pitch control and to use that model to designcontrollers. This report describes the model...... developed for controller design and analysis. Emphasis has been put on establishment of simple models describing the dynamic behavior of the wind turbine in adequate details for controller design. This hasbeen done with extensive use of measurements as the basis for selection of model complexity and model....... The models are all formulated as linear differential equations. The models are validated throughcomparisons with measurements performed on a Vestas WD 34 400 kW wind turbine. It is shown from a control point of view simple linear models can be used to describe the dynamic behavior of a pitch controlled wind...

  11. Reliability Assessment Of Wind Turbines

    DEFF Research Database (Denmark)

    Sørensen, John Dalsgaard

    2014-01-01

    Reduction of cost of energy for wind turbines are very important in order to make wind energy competitive compared to other energy sources. Therefore the turbine components should be designed to have sufficient reliability but also not be too costly (and safe). This paper presents models...... for uncertainty modeling and reliability assessment of especially the structural components such as tower, blades, substructure and foundation. But since the function of a wind turbine is highly dependent on many electrical and mechanical components as well as a control system also reliability aspects...... of these components are discussed and it is described how there reliability influences the reliability of the structural components. Two illustrative examples are presented considering uncertainty modeling, reliability assessment and calibration of partial safety factors for structural wind turbine components exposed...

  12. Probabilistic Design of Wind Turbines

    DEFF Research Database (Denmark)

    Sørensen, John Dalsgaard; Toft, H.S.

    2010-01-01

    Probabilistic design of wind turbines requires definition of the structural elements to be included in the probabilistic basis: e.g., blades, tower, foundation; identification of important failure modes; careful stochastic modeling of the uncertain parameters; recommendations for target reliability....... It is described how uncertainties in wind turbine design related to computational models, statistical data from test specimens, results from a few full-scale tests and from prototype wind turbines can be accounted for using the Maximum Likelihood Method and a Bayesian approach. Assessment of the optimal...... reliability level by cost-benefit optimization is illustrated by an offshore wind turbine example. Uncertainty modeling is illustrated by an example where physical, statistical and model uncertainties are estimated....

  13. Meteorological Controls on Wind Turbine Wakes

    DEFF Research Database (Denmark)

    Barthelmie, Rebecca J.; Hansen, Kurt Schaldemose; Pryor, S.C.

    2013-01-01

    The primary control on the magnitude of the power losses induced by wind turbine wakes in large wind farms is the hub-height wind speed via its link to the turbine thrust coefficient. Hence, at low to moderate wind speeds (between cut-in and rated turbine wind speeds) when the thrust coefficient ...

  14. Innovative multi rotor wind turbine designs

    Energy Technology Data Exchange (ETDEWEB)

    Kale, S.A.; Sapali, S.N. [College of Engineering. Mechanical Engineering Dept, Pune (India)

    2012-07-01

    Among the renewable energy sources, today wind energy is the most recognized and cost effective. Developers and researchers in this sector are optimistic and continuously working innovatively to improve the technology. The wind power obtained is proportional to the swept area of wind turbine. The swept area is increased by using a single rotor of large diameter or multi rotors in array. The rotor size is growing continuously with mature technology. Multi rotor technology has a long history and the multi rotor concept persists in a variety of modern innovative systems but the concept has fallen out of consideration in mainstream design from the perception that is complex and unnecessary as very large single rotor units are now technically feasible. This work addresses the evaluation of different multi rotor wind turbine systems. These innovative wind turbines are evaluated on the basis of feasibility, technological advantages, security of expected power performance, cost, reliability, impact of innovative system, comparison with existing wind turbine design. The findings of this work will provide guidelines for the practical and economical ways for further research on the multi rotor wind turbines. (Author)

  15. The aerodynamics of wind turbines

    DEFF Research Database (Denmark)

    Sørensen, Jens Nørkær; Mikkelsen, Robert Flemming; Troldborg, Niels

    2013-01-01

    In the paper we present state-of-the-art of research in wind turbine aerodynamics. We start be giving a brief historical review and a survey over aerodynamic research in wind energy. Next, we focus on some recent research results obtained by our wind energy group at Department of Mechanical...... Engineering at DTU. In particular, we show some new results on the classical problem of the ideal rotor and present a series of new results from an on-going research project dealing with the modelling and simulation of turbulent flow structures in the wake behind wind turbines....

  16. Power Curves in a Wind Turbine Array: A Numerical Study

    DEFF Research Database (Denmark)

    Meyer Forsting, Alexander Raul

    The impact of measuring a power curve inside a wind turbine array is investigated using computational fluid dynamics. The array consists of five aligned rotors that yaw with the free-stream wind direction. The flow-field in front of a wind turbine array changes with wind direction and hence...... the individual power output of each turbine. By incorporating the current IEC standards on power performance measurements, the bias in the power performance of turbines in an array over an isolated rotor is determined. The power change depends on the position of the turbine in the array and reaches maximally 9...

  17. CFD analysis of a Darrieus wind turbine

    Science.gov (United States)

    Niculescu, M. L.; Cojocaru, M. G.; Pricop, M. V.; Pepelea, D.; Dumitrache, A.; Crunteanu, D. E.

    2017-07-01

    The Darrieus wind turbine has some advantages over the horizontal-axis wind turbine. Firstly, its tip speed ratio is lower than that of the horizontal-axis wind turbine and, therefore, its noise is smaller, privileging their placement near populated areas. Secondly, the Darrieus wind turbine does needs no orientation mechanism with respect to wind direction in contrast to the horizontal-axis wind turbine. However, the efficiency of the Darrieus wind turbine is lower than that of the horizontal-axis wind turbine since its aerodynamics is much more complex. With the advances in computational fluids and computers, it is possible to simulate the Darrieus wind turbine more accurately to understand better its aerodynamics. For these reasons, the present papers deals with the computational aerodynamics of a Darrieus wind turbine applying the state of the art of CFD methods (anisotropic turbulence models, transition from laminar to turbulent, scale adaptive simulation) to better understand its unsteady behavior.

  18. Lightning protection of wind turbines

    Energy Technology Data Exchange (ETDEWEB)

    Soerensen, T.; Brask, M.H. [DEFU (Denmark); Jensen, F.V.; Raben, N. [SEAS (Denmark); Saxov, J. [Nordjyllandsvaerket (Denmark); Nielsen, L. [Vestkraft (Denmark); Soerensen, P.E. [Risoe National Lab. (Denmark)

    1999-03-01

    Lightning damage to wind turbines is a serious problem for Danish power companies, who have experienced some cases with very costly lightning damage and a large number of cases with minor damage. The most costly cases include one catastrophic damage to an entire wind turbine, and several cases of destruction of blades, main bearings, generators and control systems. Over the years there have been several hundreds of cases with minor damage - typically damage and interruptions of the control and communication systems, or the power systems. The Danish power companies anticipate that the lightning threat will be even bigger for the large off-shore wind turbine installations that are currently being planned in Denmark. Furthermore, it is known from the off-shore wind turbines at Vindeby in Denmark that the costs of inspection and particularly repair work must be expected to be much higher off-shore as compared to wind turbines on land. These considerations was the background for a two year project concerned with investigation of lighting damages and with the formulation of a DEFU Recommendation for lightning protection of wind turbines, which was published in January 1999. The project was funded by the Danish power companies Elsam, Eltra, Elkraft and by DEFU. (au)

  19. Upscaling wind turbines: theoretical and practical aspects and their impact on the cost of energy

    DEFF Research Database (Denmark)

    Sieros, G.; Chaviaropoulos, P.; Sørensen, John Dalsgaard

    2012-01-01

    to 250 m and a hub height of more than 150 m. Initially, the theoretical implications of upscaling to such sizes on the weight and loads of the wind turbines are examined, where it is shown that unfavourable increases in weight and load will have to be addressed. Following that, empirical models......‐efficient way. Finally, a theoretical framework for optimal design of large wind turbines is developed. This is based on a life cycle cost approach, with the introduction of generic models for the costs, as functions of the design parameters and using basic upscaling laws adjusted for technology improvement...... effects. The optimal concept or concepts is obtained as the one that minimizes the total expected costs per megawatt hour (levelized production costs). Copyright © 2011 John Wiley & Sons, Ltd....

  20. Conference on raw materials and jobs cost variation - Impact on wind turbine manufacturers and operators

    International Nuclear Information System (INIS)

    Chabot, Bernard; Falk, Thorsten; Braeuninger, Michael; Rehfeldt, Knud; Brand, Ruth; Buhr, Ingo de; Jenne, Markus

    2007-01-01

    In the framework of the 2007 Husum Wind exhibition, the French-German office for Renewable energies (OFAEnR) organised a side event on In the framework of this French-German exchange of experience, participants exchanged views on raw materials and jobs cost variations in the wind power industry in both countries. Its aim was to compare and analyse the French and German respective support systems to renewable energy sources. This document brings together the available presentations (slides) made during this event: 1 - Protecting wind energy tariffs against inflation effects: analysis and suggestions from the French experience (Bernard Chabot); 2 - Wind energy in Germany - Tariff structure in the EEG renewable energy law (Thorsten Falk); 3 - Wind energy competitiveness (Michael Braeuninge, Knud Rehfeldt); 4 - Influence of raw materials price rise on the production costs of ENERCON wind turbines maker (Ruth Brand); 5 - Presentation of the overall costs of an offshore wind energy project (Ingo de Buhr); 6 - Comparison between French and German tariffs profitability using a model wind farm: presentation of the pros and cons of both systems (Markus Jenne)

  1. Mapping of grid faults and grid codes[Wind turbines

    Energy Technology Data Exchange (ETDEWEB)

    Iov, F. [Aalborg Univ., Inst. of Energy Technology (Denmark); Hansen, Anca D.; Soerensen, Poul; Cutululis, N.A. [Risoe National Lab. - DTU, Wind Enegy Dept., Roskilde (Denmark)

    2007-06-15

    The objective of this project is to investigate into the consequences of the new grid connection requirements for the fatigue and extreme loads of wind turbines. The goal is also to clarify and define possible new directions in the certification process of power plant wind turbines, namely wind turbines, which participate actively in the stabilisation of power systems. Practical experience shows that there is a need for such investigations. The grid connection requirements for wind turbines have increased significantly during the last 5-10 years. Especially the requirements for wind turbines to stay connected to the grid during and after voltage sags, imply potential challenges in the design of wind turbines. These requirements pose challenges for the design of both the electrical system and the mechanical structure of wind turbines. An overview over the frequency of grid faults and the grid connection requirements in different relevant countries is done in this report. The most relevant study cases for the quantification of the loads' impact on the wind turbines' lifetime are defined. The goal of this report is to present a mapping of different grid fault types and their frequency in different countries. The report provides also a detailed overview of the Low Voltage Ride-Through Capabilities for wind turbines in different relevant countries. The most relevant study cases for the quantification of the loads' impact on the wind turbines' lifetime are defined. (au)

  2. ASSESSMENT OF THE IMPACT OF THE NATIONAL GRID AND OF THE MAINTENANCE PERIODS ON THE OPTIMIZATION OF THE WIND TURBINE OPERATION

    Directory of Open Access Journals (Sweden)

    GHEORGHE SAMOILESCU

    2016-06-01

    Full Text Available The upsurge in the value of wind energy in Romania may have occurred due to a constructive development of wind turbines, their dimensions and the increase in their number of units in wind farms. The modern design of large wind turbines, corroborated with an appropriate wind speed leads to a significant production of green energy. In order to obtain a greater amount of energy, modern turbines are fitted with many devices which are exploited by high -tech electronic circuits. Instruments of remote detection, measurement devices and control processes of the main measurement systems are based on various types of electronic apparatus. These appliances are very sensitive to tension variation caused by abnormal conditions of turbine operation and by the national electrical grid which the wind farm is connected to. The paper aims at providing an assessment of a wind farm registers as well as a set of methods meant to overcome such obstacles related to designing large wind turbines. Similarly, the paper offers a classification of the various types of abnormalities that appear in the installation connected to the electric grid, such as a sudden power cut, unplugging or tension variation. The difficulty of such an impact is to be determined for every type of disorder associated to electronic glitches occurring in wind turbines .

  3. The impact of inertial forces on morphing wind turbine blade in vertical axis configuration

    International Nuclear Information System (INIS)

    Butbul, Jonathan; MacPhee, David; Beyene, Asfaw

    2015-01-01

    Highlights: • A novel flexible VAWT has been experimentally tested alongside numerically simulations. • Using FEA and CFD, direction of blade bending was predicted from inertial and aerodynamic forces. • High-speed camera footage has been used to validate the model. • The flexible VAWT was found to self-start in the majority of tests, while the rigid one did not. • It is suggested that flexible VAWTs can have improved performance in part-load applications. - Abstract: A novel flexible blade concept with the ability to morph and geometrically adapt to changing flow conditions has been proposed to improve part-load performance of horizontal-axis wind turbines. The extension of these benefits to a vertical axis wind turbine would make wind technology a more competitive player in the energy market. Both flexible and rigid wind turbine rotor blades for vertical axis application were modeled, designed, manufactured and tested. Their performances were tested in a low speed wind tunnel. The predicted magnitude and direction of blade morph was validated using a high speed camera as well as finite element analysis. The comparative results of straight rigid and straight morphing blades show that the coefficient of performance greatly depends on the tip speed ratio. Overall, the morphing blade has better performance at low RPMs, but the rigid blade performed better at high RPMs. It was observed that the flexible blade self-started in the majority of the experiments. At high RPM, the centrifugal force overwhelmed the lift force, bending the flexible blade out of phase in an undesired direction increasing drag and therefore reducing the coefficient of performance

  4. Foundations for offshore wind turbines.

    Science.gov (United States)

    Byrne, B W; Houlsby, G T

    2003-12-15

    An important engineering challenge of today, and a vital one for the future, is to develop and harvest alternative sources of energy. This is a firm priority in the UK, with the government setting a target of 10% of electricity from renewable sources by 2010. A component central to this commitment will be to harvest electrical power from the vast energy reserves offshore, through wind turbines or current or wave power generators. The most mature of these technologies is that of wind, as much technology transfer can be gained from onshore experience. Onshore wind farms, although supplying 'green energy', tend to provoke some objections on aesthetic grounds. These objections can be countered by locating the turbines offshore, where it will also be possible to install larger capacity turbines, thus maximizing the potential of each wind farm location. This paper explores some civil-engineering problems encountered for offshore wind turbines. A critical component is the connection of the structure to the ground, and in particular how the load applied to the structure is transferred safely to the surrounding soil. We review previous work on the design of offshore foundations, and then present some simple design calculations for sizing foundations and structures appropriate to the wind-turbine problem. We examine the deficiencies in the current design approaches, and the research currently under way to overcome these deficiencies. Designs must be improved so that these alternative energy sources can compete economically with traditional energy suppliers.

  5. 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

    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......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...

  6. Extreme Response for Wind Turbines

    DEFF Research Database (Denmark)

    Toft, Henrik Stensgaard; Sørensen, John Dalsgaard

    2009-01-01

    The characteristic load on wind turbines during operation are among others dependent on the mean wind speed, the turbulence intensity and type and settings of the control system. The characteristic load during operation is normally estimated by statistical extrapolation of a limited number...... of simulated 10min time series of the response according to the wind turbine standard IEC 61400-1. However, this method assumes that the individual 10min time series and the extracted peaks from the time series are independent. In the present paper is this assumption investigated based on field measurements...

  7. Reliability assessment of Wind turbines

    DEFF Research Database (Denmark)

    Sørensen, John Dalsgaard

    2015-01-01

    but manufactured in series production based on many component tests, some prototype tests and zeroseries wind turbines. These characteristics influence the reliability assessment where focus in this paper is on the structural components. Levelized Cost Of Energy is very important for wind energy, especially when...... comparing to other energy sources. Therefore much focus is on cost reductions and improved reliability both for offshore and onshore wind turbines. The wind turbine components should be designed to have sufficient reliability level with respect to both extreme and fatigue loads but also not be too costly...... (and safe). In probabilistic design the single components are designed to a level of reliability, which accounts for an optimal balance between failure consequences, cost of operation & maintenance, material costs and the probability of failure. Furthermore, using a probabilistic design basis...

  8. Ultimate loading of wind turbines

    DEFF Research Database (Denmark)

    Larsen, Gunner Chr.; Ronold, K.; Ejsing Jørgensen, Hans

    1999-01-01

    An extreme loading study has been conducted comprising a general wind climate analysis as well as a wind turbine reliability study. In the wind climate analysis, the distribution of the (horizontal) turbulence standard deviation, conditioned on the meanwind speed, has been approximated by fitting......, a design turbulence intensity for off-shore application is proposed which, in the IEC code framework, is applicable for extreme as well as for fatigue loaddetermination. In order to establish a rational method to analyse wind turbine components with respect to failure in ultimate loading, and in addition...... to the event of failure in ultimate loading in flapwise bending in the normal operating condition of a site-specific turbine....

  9. Active control: Wind turbine model

    Energy Technology Data Exchange (ETDEWEB)

    Bindner, Henrik

    1999-07-01

    This report is a part of the reporting of the work done in the project `Active Control of Wind Turbines`. This project aim is to develop a simulation model for design of control systems for turbines with pitch control and to use that model to design controllers. This report describes the model developed for controller design and analysis. Emphasis has been put on establishment of simple models describing the dynamic behavior of the wind turbine in adequate details for controller design. This has been done with extensive use of measurements as the basis for selection of model complexity and model validation as well as parameter estimation. The model includes a simple model of the structure of the turbine including tower and flapwise blade bending, a detailed model of the gear box and induction generator, a linearized aerodynamic model including modelling of induction lag and actuator and sensor models. The models are all formulated as linear differential equations. The models are validated through comparisons with measurements performed on a Vestas WD 34 400 kW wind turbine. It is shown from a control point of view simple linear models can be used to describe the dynamic behavior of a pitch controlled wind turbine. The model and the measurements corresponds well in the relevant frequency range. The developed model is therefore applicable for controller design. (au) EFP-91. 18 ills., 22 refs.

  10. Lidar-Enhanced Wind Turbine Control: Past, Present, and Future

    Energy Technology Data Exchange (ETDEWEB)

    Scholbrock, Andrew; Fleming, Paul; Schlipf, David; Wright, Alan; Johnson, Kathryn; Wang, Na

    2016-08-01

    The main challenges in harvesting energy from the wind arise from the unknown incoming turbulent wind field. Balancing the competing interests of reduction in structural loads and increasing energy production is the goal of a wind turbine controller to reduce the cost of producing wind energy. Conventional wind turbines use feedback methods to optimize these goals, reacting to wind disturbances after they have already impacted the wind turbine. Lidar sensors offer a means to provide additional inputs to a wind turbine controller, enabling new techniques to improve control methods, allowing a controller to actuate a wind turbine in anticipation of an incoming wind disturbance. This paper will look at the development of lidar-enhanced controls and how they have been used for various turbine load reductions with pitch actuation, as well as increased energy production with improved yaw control. Ongoing work will also be discussed to show that combining pitch and torque control using feedforward nonlinear model predictive control can lead to both reduced loads and increased energy production. Future work is also proposed on extending individual wind turbine controls to the wind plant level and determining how lidars can be used for control methods to further lower the cost of wind energy by minimizing wake impacts in a wind farm.

  11. Investigation of the Impact of the Upstream Induction Zone on LIDAR Measurement Accuracy for Wind Turbine Control Applications using Large-Eddy Simulation

    International Nuclear Information System (INIS)

    Simley, Eric; Pao, Lucy Y; Gebraad, Pieter; Churchfield, Matthew

    2014-01-01

    Several sources of error exist in lidar measurements for feedforward control of wind turbines including the ability to detect only radial velocities, spatial averaging, and wind evolution. This paper investigates another potential source of error: the upstream induction zone. The induction zone can directly affect lidar measurements and presents an opportunity for further decorrelation between upstream wind and the wind that interacts with the rotor. The impact of the induction zone is investigated using the combined CFD and aeroelastic code SOWFA. Lidar measurements are simulated upstream of a 5 MW turbine rotor and the true wind disturbances are found using a wind speed estimator and turbine outputs. Lidar performance in the absence of an induction zone is determined by simulating lidar measurements and the turbine response using the aeroelastic code FAST with wind inputs taken far upstream of the original turbine location in the SOWFA wind field. Results indicate that while measurement quality strongly depends on the amount of wind evolution, the induction zone has little effect. However, the optimal lidar preview distance and circular scan radius change slightly due to the presence of the induction zone

  12. WindPACT Reference Wind Turbines

    Energy Technology Data Exchange (ETDEWEB)

    Dykes, Katherine L [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Rinker, Jennifer [Former National Renewable Energy Laboratory (NREL) employee

    2018-04-02

    To fully understand how loads and turbine cost scale with turbine size, it is necessary to have identical turbine models that have been scaled to different rated powers. The report presents the WindPACT baseline models, which are a series of four baseline models that were designed to facilitate investigations into the scalings of loads and turbine cost with size. The models have four different rated powers (750 kW, 1.5 MW, 3.0 MW, and 5.0 MW), and each model was designed to its specified rated power using the same design methodology. The models were originally implemented in FAST_AD, the predecessor to NREL's open-source wind turbine simulator FAST, but have yet to be implemented in FAST. This report contains the specifications for all four WindPACT baseline models - including structural, aerodynamic, and control specifications - along with the inherent assumptions and equations that were used to calculate the model parameters. It is hoped that these baseline models will serve as extremely useful resources for investigations into the scalings of costs, loads, or optimization routines.

  13. Vertical axis wind turbine airfoil

    Science.gov (United States)

    Krivcov, Vladimir; Krivospitski, Vladimir; Maksimov, Vasili; Halstead, Richard; Grahov, Jurij Vasiljevich

    2012-12-18

    A vertical axis wind turbine airfoil is described. The wind turbine airfoil can include a leading edge, a trailing edge, an upper curved surface, a lower curved surface, and a centerline running between the upper surface and the lower surface and from the leading edge to the trailing edge. The airfoil can be configured so that the distance between the centerline and the upper surface is the same as the distance between the centerline and the lower surface at all points along the length of the airfoil. A plurality of such airfoils can be included in a vertical axis wind turbine. These airfoils can be vertically disposed and can rotate about a vertical axis.

  14. Model Predictive Control of Wind Turbines

    DEFF Research Database (Denmark)

    Henriksen, Lars Christian

    Wind turbines play a major role in the transformation from a fossil fuel based energy production to a more sustainable production of energy. Total-cost-of-ownership is an important parameter when investors decide in which energy technology they should place their capital. Modern wind turbines...... are controlled by pitching the blades and by controlling the electro-magnetic torque of the generator, thus slowing the rotation of the blades. Improved control of wind turbines, leading to reduced fatigue loads, can be exploited by using less materials in the construction of the wind turbine or by reducing...... the need for maintenance of the wind turbine. Either way, better total-cost-of-ownership for wind turbine operators can be achieved by improved control of the wind turbines. Wind turbine control can be improved in two ways, by improving the model on which the controller bases its design or by improving...

  15. WIND TURBINE OPERATION PARAMETER CHARACTERISTICS AT A GIVEN WIND SPEED

    Directory of Open Access Journals (Sweden)

    Zdzisław Kamiński

    2014-06-01

    Full Text Available This paper discusses the results of the CFD simulation of the flow around Vertical Axis Wind Turbine rotor. The examined rotor was designed following patent application no. 402214. The turbine operation is characterised by parameters, such as opening angle of blades, power, torque, rotational velocity at a given wind velocity. Those parameters have an impact on the performance of entire assembly. The distribution of forces acting on the working surfaces in the turbine can change, depending on the angle of rotor rotation. Moreover, the resultant force derived from the force acting on the oncoming and leaving blades should be as high as possible. Accordingly, those parameters were individually simulated over time for each blade in three complete rotations. The attempts to improve the performance of the entire system resulted in a new research trend to improve the performance of working turbine rotor blades.

  16. Materials for Wind Turbine Blades: An Overview.

    Science.gov (United States)

    Mishnaevsky, Leon; Branner, Kim; Petersen, Helga Nørgaard; Beauson, Justine; McGugan, Malcolm; Sørensen, Bent F

    2017-11-09

    A short overview of composite materials for wind turbine applications is presented here. Requirements toward the wind turbine materials, loads, as well as available materials are reviewed. Apart from the traditional composites for wind turbine blades (glass fibers/epoxy matrix composites), natural composites, hybrid and nanoengineered composites are discussed. Manufacturing technologies for wind turbine composites, as well their testing and modelling approaches are reviewed.

  17. Materials for Wind Turbine Blades: An Overview

    DEFF Research Database (Denmark)

    Mishnaevsky, Leon; Branner, Kim; Petersen, Helga Nørgaard

    2017-01-01

    A short overview of composite materials for wind turbine applications is presented here. Requirements toward the wind turbine materials, loads, as well as available materials are reviewed. Apart from the traditional composites for wind turbine blades (glass fibers/epoxy matrix composites), natural...... composites, hybrid and nanoengineered composites are discussed. Manufacturing technologies for wind turbine composites, as well their testing and modelling approaches are reviewed....

  18. Radar-cross-section reduction of wind turbines. part 1.

    Energy Technology Data Exchange (ETDEWEB)

    Brock, Billy C.; Loui, Hung; McDonald, Jacob J.; Paquette, Joshua A.; Calkins, David A.; Miller, William K.; Allen, Steven E.; Clem, Paul Gilbert; Patitz, Ward E.

    2012-03-05

    In recent years, increasing deployment of large wind-turbine farms has become an issue of growing concern for the radar community. The large radar cross section (RCS) presented by wind turbines interferes with radar operation, and the Doppler shift caused by blade rotation causes problems identifying and tracking moving targets. Each new wind-turbine farm installation must be carefully evaluated for potential disruption of radar operation for air defense, air traffic control, weather sensing, and other applications. Several approaches currently exist to minimize conflict between wind-turbine farms and radar installations, including procedural adjustments, radar upgrades, and proper choice of low-impact wind-farm sites, but each has problems with limited effectiveness or prohibitive cost. An alternative approach, heretofore not technically feasible, is to reduce the RCS of wind turbines to the extent that they can be installed near existing radar installations. This report summarizes efforts to reduce wind-turbine RCS, with a particular emphasis on the blades. The report begins with a survey of the wind-turbine RCS-reduction literature to establish a baseline for comparison. The following topics are then addressed: electromagnetic model development and validation, novel material development, integration into wind-turbine fabrication processes, integrated-absorber design, and wind-turbine RCS modeling. Related topics of interest, including alternative mitigation techniques (procedural, at-the-radar, etc.), an introduction to RCS and electromagnetic scattering, and RCS-reduction modeling techniques, can be found in a previous report.

  19. Nonlinear Dynamics of Wind Turbine Wings

    DEFF Research Database (Denmark)

    Larsen, Jesper Winther

    Wind turbines with a nominal effect of 5MW with a rotor diameter of up to 126m are produced today. With the increasing size wind turbines also become more and more optimized with respect to structural dimensions and material usage, without increasing the stiffness proportionally. Consequently......, large wind turbines become increasingly flexible and dynamically sensitive. This project focuses on the structural analysis of highly flexible wind turbine wings, and the aerodynamic loading of wind turbine wings under large changes in flow field due to elastic deformations and changing wind conditions....

  20. Wind turbine with lightning protection system

    DEFF Research Database (Denmark)

    2016-01-01

    The present invention relates to a wind turbine comprising a lightning protection system comprising a waveguide interconnecting a communication device and a signal-carrying structure. In other aspects, the present invention relates to the use of a waveguide in a lightning protection system...... of a wind turbine, a power splitter and its use in a lightning protection system of a wind turbine....

  1. Dynamic behavior of parked wind turbine at extreme wind speed

    DEFF Research Database (Denmark)

    Totsuka, Yoshitaka; Imamura, Hiroshi; Yde, Anders

    2016-01-01

    In wind turbine design process, a series of load analysis is generally performed to determine ultimate and fatigue loads under various design load cases (DLCs) which is specified in IEC 61400. These design load scenario covers not only normal operating condition but also startup, shutdown, parked...... of standstill and idling is analyzed by time domain simulations using two different coupled aero-hydro-servo-elastic codes. Trend in modern wind turbines is development of bigger, lighter and more flexible rotors where vibration issues may cause aero-elastic instabilities which have a serious impact...

  2. The impact of psychological factors on self-reported sleep disturbance among people living in the vicinity of wind turbines.

    Science.gov (United States)

    Jalali, Leila; Nezhad-Ahmadi, Mohammad-Reza; Gohari, Mahmood; Bigelow, Philip; McColl, Stephen

    2016-07-01

    Canada's wind energy capacity has grown from approximately 137MW (MW) in 2000 to over 9700MW in 2014, and this progressive development has made Canada the fifth-largest market in the world for the installation of new wind turbines (WTs). Although wind energy is now one of the fastest growing sources of power in Canada and many other countries, the growth in both number and size of WTs has raised questions regarding potential health impacts on individuals who live close to such turbines. This study is the first published research using a prospective cohort design, with noise and sleep measurements obtained before and after installation of WTs to investigate effect of such turbines on self-reported sleep disturbances of nearby residents. Subjective assessment of sleep disturbance was conducted in Ontario, Canada through standard sleep and sleepiness scales, including the Pittsburgh Sleep Quality Index (PSQI), Insomnia Severity Index (ISI), and Epworth daytime Sleepiness Scale (ESS). Both audible and infra-sound noises were also measured inside the bedroom. Descriptive and comparison analyses were performed to investigate the effect of WT exposure on sleep data. Results of the analysis show that participants reported poorer sleep quality if they had a negative attitude to WTs, if they had concerns related to property devaluation, and if they could see turbines from their properties. This study provides evidence for the role of individual differences and psychological factors in reports of sleep disturbance by people living in the vicinity of WTs. Crown Copyright © 2016. Published by Elsevier Inc. All rights reserved.

  3. Wind turbine generator trends for site-specific tailoring

    Science.gov (United States)

    Jackson, K.; van Dam, C. P.; Yen-Nakafuji, D.

    2005-10-01

    Turbine optimization for specific wind regimes and climate conditions is becoming more common as the market expands into new territories (offshore, low-wind regimes) and as technology matures. Tailoring turbines for specific sites by varying rotor diameter, tower height and power electronics may be a viable technique to make wind energy more economic and less intermittent. By better understanding the wind resource trends and evaluating important wind turbine performance parameters such as specific power (ratio of rated power and rotor swept area), developers and operators can optimize plant output and better anticipate operational impacts. This article presents a methodology to evaluate site-specific wind data for turbine tailoring. Wind characteristics for the Tehachapi wind resource area in California were utilized for this study. These data were used to evaluate the performance of a range of wind turbine configurations. The goal was to analyse the variations in wind power output for the area, assess the changes in these levels with the time of day and season and determine how turbine configuration affects the output. Wind turbine output was compared with California statewide system electrical demand to evaluate the correlation of the wind resource site with local peak demand loads. A comparison of the commercial value of electricity and corresponding wind generation is also presented using a time-dependent valuation methodology. Copyright

  4. Built Environment Wind Turbine Roadmap

    Energy Technology Data Exchange (ETDEWEB)

    Smith, J. [National Renewable Energy Lab. (NREL), Golden, CO (United States); Forsyth, T. [National Renewable Energy Lab. (NREL), Golden, CO (United States); Sinclair, K. [National Renewable Energy Lab. (NREL), Golden, CO (United States); Oteri, F. [National Renewable Energy Lab. (NREL), Golden, CO (United States)

    2012-11-01

    The market currently encourages BWT deployment before the technology is ready for full-scale commercialization. To address this issue, industry stakeholders convened a Rooftop and Built-Environment Wind Turbine Workshop on August 11 - 12, 2010, at the National Wind Technology Center, located at the U.S. Department of Energy’s National Renewable Energy Laboratory in Boulder, Colorado. This report summarizes the workshop.

  5. The noise generated by wind turbines

    International Nuclear Information System (INIS)

    Anon.

    2012-01-01

    Sound propagation damps down with distance and varies according to different parameters like wind direction and temperature. This article begins by recalling the basic physics of sound wave propagation and gives a list of common noises and corresponding decibels. The habitual noise of wind turbines 500 m away is 35 decibels which ranks it between a quiet bedroom (30 decibels) and a calm office (40 decibels). The question about whether wind turbines are a noise nuisance is all the more difficult as the feeling of a nuisance is so objective and personal. Any project of wind turbines requires a thorough study of its estimated acoustic impact. This study is a 3 step approach: first the initial noise environment is measured, secondly the propagation of the sound generated by the wind turbine farm is modelled and adequate mitigation measures are proposed to comply the law. The law stipulates that the increase of noise must be less than 5 db during daylight and less than 3 db during night. (A.C.)

  6. A wind turbine hybrid simulation framework considering aeroelastic effects

    Science.gov (United States)

    Song, Wei; Su, Weihua

    2015-04-01

    In performing an effective structural analysis for wind turbine, the simulation of turbine aerodynamic loads is of great importance. The interaction between the wake flow and the blades may impact turbine blades loading condition, energy yield and operational behavior. Direct experimental measurement of wind flow field and wind profiles around wind turbines is very helpful to support the wind turbine design. However, with the growth of the size of wind turbines for higher energy output, it is not convenient to obtain all the desired data in wind-tunnel and field tests. In this paper, firstly the modeling of dynamic responses of large-span wind turbine blades will consider nonlinear aeroelastic effects. A strain-based geometrically nonlinear beam formulation will be used for the basic structural dynamic modeling, which will be coupled with unsteady aerodynamic equations and rigid-body rotations of the rotor. Full wind turbines can be modeled by using the multi-connected beams. Then, a hybrid simulation experimental framework is proposed to potentially address this issue. The aerodynamic-dominant components, such as the turbine blades and rotor, are simulated as numerical components using the nonlinear aeroelastic model; while the turbine tower, where the collapse of failure may occur under high level of wind load, is simulated separately as the physical component. With the proposed framework, dynamic behavior of NREL's 5MW wind turbine blades will be studied and correlated with available numerical data. The current work will be the basis of the authors' further studies on flow control and hazard mitigation on wind turbine blades and towers.

  7. An investigation on wind turbine resonant vibrations

    DEFF Research Database (Denmark)

    Tibaldi, Carlo; Kim, Taeseong; Larsen, Torben J.

    2016-01-01

    Wind turbine resonant vibrations are investigated based on aeroelastic simulations both in frequency and time domain. The investigation focuses on three different aspects: the need of a precise modeling when a wind turbine is operating close to resonant conditions; the importance of estimating wind...... turbine loads also at low turbulence intensity wind conditions to identify the presence of resonances; and the wind turbine response because of external excitations. In the first analysis, three different wind turbine models are analysed with respect to the frequency and damping of the aeroelastic modes....... Fatigue loads on the same models are then investigated with two different turbulence intensities to analyse the wind turbine response. In the second analysis, a wind turbine model is excited with an external force. This analysis helps in identifying the modes that might be excited, and therefore...

  8. Dynamic modeling and simulation of wind turbines

    International Nuclear Information System (INIS)

    Ghafari Seadat, M.H.; Kheradmand Keysami, M.; Lari, H.R.

    2002-01-01

    Using wind energy for generating electricity in wind turbines is a good way for using renewable energies. It can also help to protect the environment. The main objective of this paper is dynamic modeling by energy method and simulation of a wind turbine aided by computer. In this paper, the equations of motion are extracted for simulating the system of wind turbine and then the behavior of the system become obvious by solving the equations. The turbine is considered with three blade rotor in wind direction, induced generator that is connected to the network and constant revolution for simulation of wind turbine. Every part of the wind turbine should be simulated for simulation of wind turbine. The main parts are blades, gearbox, shafts and generator

  9. Rotor and wind turbine formalism

    DEFF Research Database (Denmark)

    Branlard, Emmanuel Simon Pierre

    2017-01-01

    The main conventions used in this book for the study of rotors are introduced in this chapter. The main assumptions and notations are provided. The formalism specific to wind turbines is presented. The forces, moments, velocities and dimensionless coefficients used in the study of rotors...

  10. Design of Wind Turbine Vibration Monitoring System

    Directory of Open Access Journals (Sweden)

    Shoubin Wang

    2013-04-01

    Full Text Available In order to ensure safety of wind turbine operation and to reduce the occurrence of faults as well as to improve the reliability of wind turbine operation, a vibration monitoring for wind turbine is developed. In this paper, it analyses the enlargement of all the parts of the structure and the working mechanism, the research method of wind turbine operation vibration is introduced, with the focus being the use of the sensor principle. Finally the hardware design and software of this system is introduced and the main function of this system is described, which realizes condition monitoring of the work state of wind turbines.

  11. Sound wave contours around wind turbine arrays

    International Nuclear Information System (INIS)

    Van Beek, A.; Van Blokland, G.J.

    1993-02-01

    Noise pollution is an important factor in selecting suitable sites for wind turbines in order to realize 1000 MW of wind power as planned by the Dutch government for the year 2000. Therefore an accurate assessment of wind turbine noise is important. The amount of noise pollution from a wind turbine depends on the wind conditions. An existing standard method to assess wind turbine noise is supplemented and adjusted. In the first part of the investigation the method was developed and applied for a solitary sound source. In the second part attention is paid to the use of the method for wind turbine arrays. It appears that the adjusted method results in a shift of the contours of the permitted noise level. In general the contours are 15-25% closer to the wind farm, which means that the minimal permitted distance between houses and wind turbine arrays can be reduced. 14 figs., 1 tab., 4 appendices, 7 refs

  12. Dynamic survey of wind turbine vibrations

    Science.gov (United States)

    Chiang, Chih-Hung; Hsu, Keng-Tsang; Cheng, Chia-Chi; Pan, Chieh-Chen; Huang, Chi-Luen; Cheng, Tao-Ming

    2016-04-01

    Six wind turbines were blown to the ground by the wind gust during the attack of Typhoon Soudelor in August 2015. Survey using unmanned aerial vehicle, UAV, found the collapsed wind turbines had been broken at the lower section of the supporting towers. The dynamic behavior of wind turbine systems is thus in need of attention. The vibration of rotor blades and supporting towers of two wind turbine systems have been measured remotely using IBIS, a microwave interferometer. However the frequency of the rotor blade can be analyzed only if the microwave measurements are taken as the wind turbine is parked and secured. Time-frequency analyses such as continuous wavelet transform and reassigned spectrograms are applied to the displacement signals obtained. A frequency of 0.44Hz exists in both turbines B and C at various operating conditions. Possible links between dynamic characteristics and structural integrity of wind turbine -tower systems is discussed.

  13. Smart Wind Turbine : Analysis and Autonomous Flap

    NARCIS (Netherlands)

    Bernhammer, L.O.

    2015-01-01

    Wind turbines convert kinetic energy of the wind into electrical energy. Unfortunately, this process is everything but constant, as the wind source shows large fluctuations with high and low frequencies. This turbulence, together with the wind shear and yawed inflow, excites the turbine structure,

  14. Structural Robustness Evaluation of Offshore Wind Turbines

    DEFF Research Database (Denmark)

    Giuliani, Luisa; Bontempi, Franco

    2010-01-01

    Wind turbines are complex structures that should deal with adverse weather conditions, are exposed to impacts or ship collisions and, due to the strategic roles in the energetic supplying, can be the goal of military or malevolent attacks. Even if a structure cannot be design to resist any...... integrity after the impact and permits to identify some characteristics of the system, which are intrinsic to the chosen organization of the elements within the structure....

  15. Aeroelastic impact of above-rated wave-induced structural motions on the near-wake stability of a floating offshore wind turbine rotor

    Science.gov (United States)

    Rodriguez, Steven; Jaworski, Justin

    2017-11-01

    The impact of above-rated wave-induced motions on the stability of floating offshore wind turbine near-wakes is studied numerically. The rotor near-wake is generated using a lifting-line free vortex wake method, which is strongly coupled to a finite element solver for kinematically nonlinear blade deformations. A synthetic time series of relatively high-amplitude/high-frequency representative of above-rated conditions of the NREL 5MW referece wind turbine is imposed on the rotor structure. To evaluate the impact of these above-rated conditions, a linear stability analysis is first performed on the near wake generated by a fixed-tower wind turbine configuration at above-rated inflow conditions. The platform motion is then introduced via synthetic time series, and a stability analysis is performed on the wake generated by the floating offshore wind turbine at the same above-rated inflow conditions. The stability trends (disturbance modes versus the divergence rate of vortex structures) of the two analyses are compared to identify the impact that above-rated wave-induced structural motions have on the stability of the floating offshore wind turbine wake.

  16. Impacts of Industrial Wind Turbine Noise on Sleep Quality: Results From a Field Study of Rural Residents in Ontario, Canada.

    Science.gov (United States)

    Lane, James D; Bigelow, Philip L; Majowicz, Shannon E; McColl, R Stephen

    2016-07-01

    The objectives of this study were to determine whether grid-connected industrial wind turbines (IWTs) are a risk factor for poor sleep quality, and if IWT noise is associated with sleep parameters in rural Ontarians. A daily sleep diary and actigraphy-derived measures of sleep were obtained from 12 participants from an IWT community and 10 participants from a comparison community with no wind power installations. The equivalent and maximum sound pressure levels within the bedroom were also assessed. No statistically significant differences were observed between IWT residents and non-IWT residents for any of the parameters measured in this study. Actigraphy and sleep diaries are feasible tools to understand the impact of IWTs on the quality of sleep for nearby residents. Further studies with larger sample sizes should be conducted to determine whether the lack of statistical significance observed here is a result of sample size, or reflects a true lack of association.

  17. Wind Turbine Tribology Seminar - A Recap

    Energy Technology Data Exchange (ETDEWEB)

    Errichello, R.; Sheng, S.; Keller, J.; Greco, A.

    2012-02-01

    Tribology is the science and engineering of interacting surfaces in relative motion. It includes the study and application of the principles of friction, lubrication, and wear. It is an important phenomenon that not only impacts the design and operation of wind turbine gearboxes, but also their subsequent maintenance requirements and overall reliability. With the major growth and increasing dependency on renewable energy, mechanical reliability is an extremely important issue. The Wind Turbine Tribology Seminar was convened to explore the state-of-the-art in wind turbine tribology and lubricant technologies, raise industry awareness of a very complex topic, present the science behind each technology, and identify possible R&D areas. To understand the background of work that had already been accomplished, and to consolidate some level of collective understanding of tribology by acknowledged experts, the National Renewable Energy Laboratory (NREL), Argonne National Laboratory (ANL), and the U.S. Department of Energy (DOE) hosted a wind turbine tribology seminar. It was held at the Renaissance Boulder Flatiron Hotel in Broomfield, Colorado on November 15-17, 2011. This report is a summary of the content and conclusions. The presentations given at the meeting can be downloaded. Interested readers who were not at the meeting may wish to consult the detailed publications listed in the bibliography section, obtain the cited articles in the public domain, or contact the authors directly.

  18. Data Driven Modelling of the Dynamic Wake Between Two Wind Turbines

    DEFF Research Database (Denmark)

    Knudsen, Torben; Bak, Thomas

    2012-01-01

    turbine. This paper establishes flow models relating the wind speeds at turbines in a farm. So far, research in this area has been mainly based on first principles static models and the data driven modelling done has not included the loading of the upwind turbine and its impact on the wind speed downwind......Wind turbines in a wind farm, influence each other through the wind flow. Downwind turbines are in the wake of upwind turbines and the wind speed experienced at downwind turbines is hence a function of the wind speeds at upwind turbines but also the momentum extracted from the wind by the upwind....... This paper is the first where modern commercial mega watt turbines are used for data driven modelling including the upwind turbine loading by changing power reference. Obtaining the necessary data is difficult and data is therefore limited. A simple dynamic extension to the Jensen wake model is tested...

  19. 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

  20. Method and apparatus for wind turbine braking

    Science.gov (United States)

    Barbu, Corneliu [Laguna Hills, CA; Teichmann, Ralph [Nishkayuna, NY; Avagliano, Aaron [Houston, TX; Kammer, Leonardo Cesar [Niskayuna, NY; Pierce, Kirk Gee [Simpsonville, SC; Pesetsky, David Samuel [Greenville, SC; Gauchel, Peter [Muenster, DE

    2009-02-10

    A method for braking a wind turbine including at least one rotor blade coupled to a rotor. The method includes selectively controlling an angle of pitch of the at least one rotor blade with respect to a wind direction based on a design parameter of a component of the wind turbine to facilitate reducing a force induced into the wind turbine component as a result of braking.

  1. Wind turbine storage systems

    International Nuclear Information System (INIS)

    Ibrahim, H.; Ilinca, A.; Perron, J.

    2005-01-01

    Electric power is often produced in locations far from the point of utilization which creates a challenge in stabilizing power grids, particularly since electricity cannot be stored. The production of decentralized electricity by renewable energy sources offers a greater security of supply while protecting the environment. Wind power holds the greatest promise in terms of environmental protection, competitiveness and possible applications. It is known that wind energy production is not always in phase with power needs because of the uncertainty of wind. For that reason, energy storage is the key for the widespread integration of wind energy into the power grids. This paper proposed various energy storage methods that can be used in combination with decentralized wind energy production where an imbalance exists between electricity production and consumption. Energy storage can play an essential role in bringing value to wind energy, particularly if electricity is to be delivered during peak hours. Various types of energy storage are already in use or are being developed. This paper identified the main characteristics of various electricity storage techniques and their applications. They include stationary or embarked storage for long or short term applications. A comparison of characteristics made it possible to determine which types of electricity storage are best suited for wind energy. These include gravity energy; thermal energy; compressed air energy; coupled storage with natural gas; coupled storage with liquefied gas; hydrogen storage for fuel cells; chemical energy storage; storage in REDOX batteries; storage by superconductive inductance; storage in supercondensers; and, storage as kinetic energy. 21 refs., 21 figs

  2. Wind Turbine Converter Control Interaction with Complex Wind Farm Systems

    DEFF Research Database (Denmark)

    Kocewiak, Lukasz Hubert; Hjerrild, Jesper; Bak, Claus Leth

    2013-01-01

    in this study. It is shown that wind farm components, such as long high-voltage alternating current cables and park transformers, can introduce significant low-frequency series resonances seen from the wind turbine terminals that can affect wind turbine control system operation and overall wind farm stability...

  3. Superconducting Wind Turbine Generators

    DEFF Research Database (Denmark)

    Mijatovic, Nenad

    in this thesis is a part of a larger endeavor, the Superwind project that focused on identifying the potentials that HTS machines could offer to the wind industry and addressing some of the challenges in the process. In order to identify these challenges, I have design and constructed a HTS machine experimental...... still be optimized towards more competitive alternative to conventional machines. Additionally, by constructing the HTS machine setup we went through most of the issues related to the HTS machine design which we managed to address in rather simple manner using everyday materials and therefore proving......A HTS machine could be a way to address some of the technical barriers offshore wind energy is about to face. Due to the superior power density of HTS machines, this technology could become a milestone on which many, including the wind industry, will rely in the future. The work presented...

  4. On the Fatigue Analysis of Wind Turbines

    Energy Technology Data Exchange (ETDEWEB)

    Sutherland, Herbert J.

    1999-06-01

    Modern wind turbines are fatigue critical machines that are typically used to produce electrical power from the wind. Operational experiences with these large rotating machines indicated that their components (primarily blades and blade joints) were failing at unexpectedly high rates, which led the wind turbine community to develop fatigue analysis capabilities for wind turbines. Our ability to analyze the fatigue behavior of wind turbine components has matured to the point that the prediction of service lifetime is becoming an essential part of the design process. In this review paper, I summarize the technology and describe the ''best practices'' for the fatigue analysis of a wind turbine component. The paper focuses on U.S. technology, but cites European references that provide important insights into the fatigue analysis of wind turbines.

  5. RBI Optimization of Offshore Wind Turbines

    DEFF Research Database (Denmark)

    Ramírez, José G. Rangel; Sørensen, John Dalsgaard

    2009-01-01

    Wind turbines for electricity production have increased significantly the last years both in production capability and size. This development is expected to continue also in the coming years. Offshore wind turbines with an electricity production of 5-10 MW are planned. Typically, the wind turbine...... support structure is a steel structure consisting of a tower and a monopile, tripod or jacket type foundation. This paper considers aspects of inspection and maintenance planning of fatigue prone details in jacket and tripod type of wind turbine support structures. Based on risk-based inspection planning...... methods for oil & gas installations, a framework for optimal inspection and maintenance planning of offshore wind turbines is presented. Special aspects for offshore wind turbines considered are the fatigue loading characteristics where usually the wind loading are dominating the wave loading, wake...

  6. Wind Turbine Generator System Acoustic Noise Test Report for the Gaia Wind 11-kW Wind Turbine

    Energy Technology Data Exchange (ETDEWEB)

    Huskey, A.

    2011-11-01

    This report details the acoustic noise test conducted on the Gaia-Wind 11-kW wind turbine at the National Wind Technology Center. The test turbine is a two- bladed, downwind wind turbine with a rated power of 11 kW. The test turbine was tested in accordance with the International Electrotechnical Commission standard, IEC 61400-11 Ed 2.1 2006-11 Wind Turbine Generator Systems -- Part 11 Acoustic Noise Measurement Techniques.

  7. The sound of high winds. The effect of atmospheric stability on wind turbine sound and microphone noise

    International Nuclear Information System (INIS)

    Van den Berg, G.P.

    2006-01-01

    In this thesis issues are raised concerning wind turbine noise and its relationship to altitude dependent wind velocity. The following issues are investigated: what is the influence of atmospheric stability on the speed and sound power of a wind turbine?; what is the influence of atmospheric stability on the character of wind turbine sound?; how widespread is the impact of atmospheric stability on wind turbine performance: is it relevant for new wind turbine projects; how can noise prediction take this stability into account?; what can be done to deal with the resultant higher impact of wind turbine sound? Apart from these directly wind turbine related issues, a final aim was to address a measurement problem: how does wind on a microphone affect the measurement of the ambient sound level?

  8. New wind turbines of high profitability

    International Nuclear Information System (INIS)

    Vrsalovic, I.

    1999-01-01

    To generate more quantities of electric energy from wind it is necessary to use the new type of wind turbine built in regulable mantle's nozzle, which the free air stream of wind replaces in programmed i.e. regulated and partially concentrated. In this way their efficiency is multiplied. New turbines are getting more power (P = f(v 3 )) from cube of higher speeds from weaker and medium winds. Short economic analysis evidently indicates that profit achieved by new wind turbines is 5 (five) times higher than that by conventional turbines. (author)

  9. 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

  10. Load Extrapolation During Operation for Wind Turbines

    DEFF Research Database (Denmark)

    Toft, Henrik Stensgaard; Sørensen, John Dalsgaard

    2008-01-01

    In the recent years load extrapolation for wind turbines has been widely considered in the wind turbine industry. Loads on wind turbines during operations are normally dependent on the mean wind speed, the turbulence intensity and the type and settings of the control system. All these parameters...... must be taken into account when characteristic load effects during operation are determined. In the wind turbine standard IEC 61400-1 a method for load extrapolation using the peak over threshold method is recommended. In this paper this method is considered and some of the assumptions are examined...

  11. Wind Turbine Manufacturing Process Monitoring

    Energy Technology Data Exchange (ETDEWEB)

    Waseem Faidi; Chris Nafis; Shatil Sinha; Chandra Yerramalli; Anthony Waas; Suresh Advani; John Gangloff; Pavel Simacek

    2012-04-26

    To develop a practical inline inspection that could be used in combination with automated composite material placement equipment to economically manufacture high performance and reliable carbon composite wind turbine blade spar caps. The approach technical feasibility and cost benefit will be assessed to provide a solid basis for further development and implementation in the wind turbine industry. The program is focused on the following technology development: (1) Develop in-line monitoring methods, using optical metrology and ultrasound inspection, and perform a demonstration in the lab. This includes development of the approach and performing appropriate demonstration in the lab; (2) Develop methods to predict composite strength reduction due to defects; and (3) Develop process models to predict defects from leading indicators found in the uncured composites.

  12. The Smart Wind Turbine

    OpenAIRE

    Halimi, Wissam; Salzmann, Christophe; Gillet, Denis

    2015-01-01

    Remote experimentation is at the core of Science Technology Engineering and Mathematics education supported by e-learning. The development and integration of remote labo- ratories in online learning activities is hindered by the inherited supporting infrastructure’s architecture and implementation. In this paper we present a remote experiment (The Smart Wind Tur- bine) built following the Smart Device Paradigm and integrated in an Inquiry Learning Space: the rich open educational resource def...

  13. A novel floating offshore wind turbine concept

    DEFF Research Database (Denmark)

    Vita, Luca; Schmidt Paulsen, Uwe; Friis Pedersen, Troels

    2009-01-01

    This paper will present a novel concept of a floating offshore wind turbine. The new concept is intended for vertical-axis wind turbine technology. The main purpose is to increase simplicity and to reduce total costs of an installed offshore wind farm. The concept is intended for deep water...

  14. Annoyance rating of wind turbine noise

    International Nuclear Information System (INIS)

    Iredale, R.A.

    1992-01-01

    This paper proposes a simple criterion for noise limitation of wind turbines: 'The La A50 from a Wind Farm should not exceeding the L A50 of the wind generated background plus 5dB at any place of potential complaint'. This criterion is then examined and developed in the light of experience to date with turbine noise complaint and procedures. (author)

  15. Diagnosis of wind turbine rotor system

    DEFF Research Database (Denmark)

    Niemann, Hans Henrik; Mirzaei, Mahmood; Henriksen, Lars Christian

    2016-01-01

    This paper describes a model free method for monitoring and fault diagnosis of the elements in a rotor system for a wind turbine. The diagnosis as well as the monitoring is done without using any model of the wind turbine and the applied controller or a description of the wind profile. The method...

  16. Ducted wind turbines : A potential energy shaper

    NARCIS (Netherlands)

    Dighe, V.V.

    2016-01-01

    In order to harvest wind resources more efficiently and to the greatest extent possible, unconventional wind turbine designs have been proposed, but never gained any acceptance in the marketplace. A team of researchers from TU Delft plans to revisit the concept of ducted wind turbines, which have

  17. Wind Turbine Control: Robust Model Based Approach

    DEFF Research Database (Denmark)

    Mirzaei, Mahmood

    . This is because, on the one hand, control methods can decrease the cost of energy by keeping the turbine close to its maximum efficiency. On the other hand, they can reduce structural fatigue and therefore increase the lifetime of the wind turbine. The power produced by a wind turbine is proportional...... to the square of its rotor radius, therefore it seems reasonable to increase the size of the wind turbine in order to capture more power. However as the size increases, the mass of the blades increases by cube of the rotor size. This means in order to keep structural feasibility and mass of the whole structure...... reasonable, the ratio of mass to size should be reduced. This trend results in more flexible structures. Control of the flexible structure of a wind turbine in a wind field with stochastic nature is very challenging. In this thesis we are examining a number of robust model based methods for wind turbine...

  18. Optimization of wind turbine rotors

    Energy Technology Data Exchange (ETDEWEB)

    Nygaard, Tor Anders

    1999-07-01

    The Constrained Steepest Descent method has been applied to the optimization of wind turbine rotors through the development of a numerical model. The model consists of an optimization kernel, an aerodynamic model, a structural dynamic model of a rotating beam, and a cost model for the wind turbine. The cost of energy is minimized directly by varying the blade design, the rotational speed and the resulting design of the drive-train and tower. The aerodynamic model is a combination of a fast engineering model based on strip-theory and two and three-dimensional Euler solvers. The two-dimensional Euler solver is used for generation of pre-stall airfoil data. Comparisons with experimental data verify that the engineering model effectively approximates non-stalled flow, except at the blade tip. The three-dimensional Euler solver is in good agreement with the experimental data at the tip, and is therefore a useful supplement for corrections of the tip-loss model, and evaluation of an optimized design. The structural dynamic model evaluates stresses and deformations for the blade. It is based on constitutive relations for a slender beam that are solved with the equations of motions using a finite-difference method. The cost model evaluates the design change of the wind turbine and the resulting costs that occur when a change in blade design modifies the blade mass and the overall forces. The cost model is based on engineering design rules for the drive-train and tower. The model was applied using a Danish 600 kW wind turbine as a reference. Two rotors were optimized using traditional NACA airfoils and a new low-lift airfoil family developed specifically for wind turbine purposes. The cost of energy decreased four percent for the NACA rotor, and seven percent for the low-lift rotor. Optimizations with a high number of degrees of freedom show that a designer has considerable flexibility in choosing some primary parameters such as rated power and rotor diameter, if the rest

  19. Power Electronics for the Next Generation Wind Turbine System

    DEFF Research Database (Denmark)

    Ma, Ke

    The wind power generation has been steadily growing both for the total installed capacity and for the individual turbine size. Due to much more significant impacts to the power grid, the power electronics, which can change the behavior of wind turbines from an unregulated power source to an active...... generation unit, are becoming crucial in the wind turbine system. The objective of this project is to study the power electronics technology used for the next generation wind turbines. Some emerging challenges as well as potentials like the cost of energy and reliability are going to be addressed. First...... several potential converter topologies and power semiconductor devices for the future wind power application are presented in respect to the advantages/drawbacks. And then the criteria for evaluating the wind power converter are generally discussed, where the importance of thermal stress in the power...

  20. Wind turbine influence on surfers wind conditions at Hanstholm

    DEFF Research Database (Denmark)

    Larsen, Torben J.; Andersen, Søren Juhl

    alter the wind conditions on the lee side, which is an important area for wind and kite surfers. The Dynamic Wake Meander Model is used to investigate the wind conditions north east of the planned new turbines at Hanstholm covering a surf area from a location called “Fish Factory” to a location called...... “Hamborg”. This model, which predicts instationary wind conditions behind one or more wind turbines, has previously been used to predict the changed power and load conditions for wind turbines in wind farm conditions. Avery fine agreement to measurements is seen and the model is therefore considered...

  1. Small Wind Research Turbine: Final Report

    Energy Technology Data Exchange (ETDEWEB)

    Corbus, D.; Meadors, M.

    2005-10-01

    The Small Wind Research Turbine (SWRT) project was initiated to provide reliable test data for model validation of furling wind turbines and to help understand small wind turbine loads. This report will familiarize the user with the scope of the SWRT test and support the use of these data. In addition to describing all the testing details and results, the report presents an analysis of the test data and compares the SWRT test data to simulation results from the FAST aeroelastic simulation model.

  2. Grid support capabilities of wind turbines

    DEFF Research Database (Denmark)

    Michalke, Gabriele; Hansen, Anca Daniela

    2013-01-01

    Wind power has gained a significant penetration level in several power systems all over the world. Due to this reason modern wind turbines are requested to contribute to power system support. Power system operators have thus introduced grid codes, which specify a set of requirements for wind...... turbines, such as fault ride-through and reactive power supply during voltage sags. To date different wind turbine concepts exist on the market comprising different control features in order to provide ancillary services to the power system. In the first place the present chapter emphasizes the most...... important issues related to wind power grid integration. Then different wind turbine concepts are characterized and their grid support capabilities are analysed and compared. Simulation cases are presented in which the respective wind turbine concepts are subjected to a voltage dip specified in a grid code....

  3. Prototype bucket foundation for wind turbines

    DEFF Research Database (Denmark)

    Ibsen, Lars Bo; Liingaard, Morten

    The first full scale prototype bucket foundation for wind turbines has been installed in October 2002 at Aalborg University offshore test facility in Frederikshavn, Denmark. The suction caisson and the wind turbine have been equipped with an online monitoring system, consisting of 15 accelerometers...... estimates are then compared with numerical simulations of the suction caisson foundation and the wind turbine. The numerical model consists of a finite element section for the wind turbine tower and nacelle. The soil-structure interaction of the soil-foundation section is modelled by lumped-parameter models...

  4. Design Load Basis for Offshore Wind turbines

    DEFF Research Database (Denmark)

    Natarajan, Anand; Hansen, Morten Hartvig; Wang, Shaofeng

    2016-01-01

    DTU Wind Energy is not designing and manufacturing wind turbines and does therefore not need a Design Load Basis (DLB) that is accepted by a certification body. However, to assess the load consequences of innovative features and devices added to existing offshore turbine concepts or new offshore...... turbine concept developed in our research, it is useful to have a full DLB that follows the current design standard and is representative of a general DLB used by the industry. It will set a standard for the offshore wind turbine design load evaluations performed at DTU Wind Energy, which is aligned...

  5. Analysis of Wind Energy Potential and Vibrations Caused by Wind Turbine on Its Basement

    Czech Academy of Sciences Publication Activity Database

    Kaláb, Z.; Hanslian, David; Stolárik, M.; Pinka, M.

    2014-01-01

    Roč. 19, č. 3 (2014), s. 151-159 ISSN 1335-1788 Institutional support: RVO:68378289 Keywords : wind turbine * wind energy potential * wind map * wind map * experimental measurement * vibration velocity Subject RIV: DG - Athmosphere Sciences, Meteorology Impact factor: 0.329, year: 2014 http://actamont.tuke.sk/pdf/2014/n3/6kalab.pdf

  6. Wind Turbine Generator System Safety and Function Test Report for the Entegrity EW50 Wind Turbine

    Energy Technology Data Exchange (ETDEWEB)

    Smith, J.; Huskey, A.; Jager, D.; Hur, J.

    2012-11-01

    This report summarizes the results of a safety and function test that NREL conducted on the Entegrity EW50 wind turbine. This test was conducted in accordance with the International Electrotechnical Commissions' (IEC) standard, Wind Turbine Generator System Part 2: Design requirements for small wind turbines, IEC 61400-2 Ed.2.0, 2006-03.

  7. Pitchcontrol of wind turbines using model free adaptivecontrol based on wind turbine code

    DEFF Research Database (Denmark)

    Zhang, Yunqian; Chen, Zhe; Cheng, Ming

    2011-01-01

    value is only based on I/O data of the wind turbine is identified and then the wind turbine system is replaced by a dynamic linear time-varying model. In order to verify the correctness and robustness of the proposed model free adaptive pitch controller, the wind turbine code FAST which can predict...

  8. Wind Turbine Generator System Safety and Function Test Report for the Ventera VT10 Wind Turbine

    Energy Technology Data Exchange (ETDEWEB)

    Smith, J.; Huskey, A.; Jager, D.; Hur, J.

    2012-11-01

    This report summarizes the results of a safety and function test that NREL conducted on the Ventera VT10 wind turbine. This test was conducted in accordance with the International Electrotechnical Commissions' (IEC) standard, Wind Turbine Generator System Part 2: Design requirements for small wind turbines, IEC 61400-2 Ed.2.0, 2006-03.

  9. Capturing the journey of wind from the wind turbines (poster)

    NARCIS (Netherlands)

    Giyanani, A.H.; Bierbooms, W.A.A.M.; Van Bussel, G.J.W.

    2015-01-01

    Wind turbine design, control strategies often assume Taylor’s frozen turbulence where the fluctuating part of the wind is assumed to be constant. In practise, the wind turbine faces higher turbulence in case of gusts and lower turbulence in some cases. With Lidar technology, the frozen turbulence

  10. Wind tunnel tests of a free yawing downwind wind turbine

    NARCIS (Netherlands)

    Verelst, D.R.S.; Larsen, T.J.; Van Wingerden, J.W.

    2014-01-01

    This research paper presents preliminary results on a behavioural study of a free yawing downwind wind turbine. A series of wind tunnel tests was performed at the TU Delft Open Jet Facility with a three bladed downwind wind turbine and a rotor radius of 0.8 meters. The setup includes an off the

  11. InfraSound from wind turbines : observations from Castle River wind farm. Volume 1

    International Nuclear Information System (INIS)

    Edworthy, J.; Hepburn, H.

    2005-01-01

    Although infrasound has been discussed as a concern by groups opposed to wind farm facilities, there is very little information available about infrasound and wind turbines. This paper presented details of a project conducted by VisionQuest, the largest wind power producer in Canada. Three sensor types were used: precision sound analyzer, seismic geophones, and calibrated microphones to take measurements in low, medium and high winds. The project also measured infrasound when the wind farm was not operating. Acquisition geometry was presented, as well as details of apparent attenuations of wind noise. It was noted that high wind noise was a dominant factor and that there was little difference when the wind farm was not operational. It was suggested that turbines have no impact with high wind, since wind noise is not attenuated with distance. It was noted that increased geophone amplitudes indicate high wind coupled motion which is attenuated when the turbines are on. Results indicate that all frequencies showed attenuation with distance. Evidence showed that low frequency sound pressure levels were often lower when the turbines were switched on. Where turbines contributed to sound pressure levels, the magnitude of the contribution was below levels of concern to human health. Ambient sound pressure levels were much higher than contributions from wind turbines. It was concluded that wind itself generates infrasound. Wind turbines generate low levels of infrasound, detectable very close to facilities at low to medium wind speeds. Wind turbines may reduce ambient infrasound levels at high wind speeds by converting the energy from the wind into electricity. refs., tabs., figs

  12. SUSTAINABLE CONCRETE FOR WIND TURBINE FOUNDATIONS.

    Energy Technology Data Exchange (ETDEWEB)

    BERNDT,M.L.

    2004-06-01

    The use of wind power to generate electricity continues to grow, especially given commitments by various countries throughout the world to ensure that a significant percentage of energy comes from renewable sources. In order to meet such objectives, increasingly larger turbines with higher capacity are being developed. The engineering aspects of larger turbine development tend to focus on design and materials for blades and towers. However, foundations are also a critical component of large wind turbines and represent a significant cost of wind energy projects. Ongoing wind research at BNL is examining two areas: (a) structural response analysis of wind turbine-tower-foundation systems and (b) materials engineering of foundations. This work is investigating the dynamic interactions in wind turbine systems, which in turn assists the wind industry in achieving improved reliability and more cost efficient foundation designs. The results reported herein cover initial studies of concrete mix designs for large wind turbine foundations and how these may be tailored to reduce cost and incorporate sustainability and life cycle concepts. The approach taken was to investigate material substitutions so that the environmental, energy and CO{sub 2}-impact of concrete could be reduced. The use of high volumes of ''waste'' materials in concrete was examined. These materials included fly ash, blast furnace slag and recycled concrete aggregate. In addition, the use of steel fiber reinforcement as a means to improve mechanical properties and potentially reduce the amount of bar reinforcement in concrete foundations was studied. Four basic mixes were considered. These were: (1) conventional mix with no material substitutions, (2) 50% replacement of cement with fly ash, (3) 50% replacement of cement with blast furnace slag and (4) 25% replacement of cement with fly ash and 25% replacement with blast furnace slag. Variations on these mixes included the addition of 1

  13. Operation and control of large wind turbines and wind farms

    Energy Technology Data Exchange (ETDEWEB)

    Soerensen, Poul; Hansen, Anca D.; Thomsen, Kenneth (and others)

    2005-09-01

    This report is the final report of a Danish research project 'Operation and control of large wind turbines and wind farms'. The objective of the project has been to analyse and assess operational strategies and possibilities for control of different types of wind turbines and different wind farm concepts. The potentials of optimising the lifetime/energy production ratio by means of using revised operational strategies for the individual wind turbines are investigated. Different strategies have been simulated, where the power production is decreased to an optimum when taking loads and actual price of produced electricity into account. Dynamic models and control strategies for the wind farms have also been developed, with the aim to optimise the operation of the wind farms considering participation in power system control of power (frequency) and reactive power (voltage), maximise power production, keep good power quality and limit mechanical loads and life time consumption. The project developed models for 3 different concepts for wind farms. Two of the concepts use active stall controlled wind turbines, one with AC connection and one with modern HVDC/VSC connection of the wind farm. The third concept is based on pitch controlled wind turbines using doubly fed induction generators. The models were applied to simulate the behaviour of the wind farm control when they were connected to a strong grid, and some initial simulations were performed to study the behaviour of the wind farms when it was isolated from the main grid on a local grid. Also the possibility to use the available information from the wind turbine controllers to predict the wind speed has been investigated. The main idea has been to predict the wind speed at a wind turbine using up-wind measurements of the wind speed in another wind turbine. (au)

  14. Simulation for Grid Connected Wind Turbines with Fluctuating

    Science.gov (United States)

    Ye, Ying; Fu, Yang; Wei, Shurong

    This paper establishes the whole dynamic model of wind turbine generator system which contains the wind speed model and DFIG wind turbines model .A simulation sample based on the mathematical models is built by using MATLAB in this paper. Research are did on the performance characteristics of doubly-fed wind generators (DFIG) which connected to power grid with three-phase ground fault and the disturbance by gust and mixed wind. The capacity of the wind farm is 9MW which consists of doubly-fed wind generators (DFIG). Simulation results demonstrate that the three-phase ground fault occurs on grid side runs less affected on the stability of doubly-fed wind generators. However, as a power source, fluctuations of the wind speed will run a large impact on stability of double-fed wind generators. The results also show that if the two disturbances occur in the meantime, the situation will be very serious.

  15. Wind turbine optimal control during storms

    International Nuclear Information System (INIS)

    Petrović, V; Bottasso, C L

    2014-01-01

    This paper proposes a control algorithm that enables wind turbine operation in high winds. With this objective, an online optimization procedure is formulated that, based on the wind turbine state, estimates those extremal wind speed variations that would produce maximal allowable wind turbine loads. Optimization results are compared to the actual wind speed and, if there is a danger of excessive loading, the wind turbine power reference is adjusted to ensure that loads stay within allowed limits. This way, the machine can operate safely even above the cut-out wind speed, thereby realizing a soft envelope-protecting cut-out. The proposed control strategy is tested and verified using a high-fidelity aeroservoelastic simulation model

  16. Status of local planning for wind turbines. Vol. 2: Jutland. Wind turbines - January 1997

    International Nuclear Information System (INIS)

    Information on the status of individual municipalities regarding wind turbine power plans, the content of the plans themselves, key figures on existing wind turbines for each municipality, overall plans for wind power development and key figures for development of wind power in Jutland - in addition to maps and lists of local authorities with either a high or a low coverage of electric power by wind turbines either now or in the future - are found in this volume. (EG)

  17. Optimization of wind turbine rotors

    Energy Technology Data Exchange (ETDEWEB)

    Holmkvist, Jonas

    1998-05-01

    A computer program for aerodynamic optimization of wind turbine rotors has been written in Fortran with the purpose to maximize the annual energy production. The constraints is the maximum power output from the turbine and maximum and minimum values on the design variables. The design of the rotor is described by the chord- and twist distribution. The chord- and twist distributions are described with Bezier splines which, with a few number of control points, are very flexible. The Bezier control points are the design variables which are optimized by the optimization program. The optimization method used in the program is the Method of Moving Asymptotes, MMA, suggested by Krister Svanberg at the Royal Institute of Technology in Stockholm. MMA is a stable method and it seems suitable for this application. It is also in general easy to implement constraints. It seems like there are many local maximum points and the variations in the annual energy production between the total maximum points are very small, so there are many solutions to choose between and finding the global maximum point can be a problem. The problem could possibly be avoided with smaller wind steps near the rated wind. In future versions of the optimization program the Reynolds number dependents of the aerodynamic coefficients should be taken into consideration. Constraints for the thrust and the aerodynamic noise should also be implemented in the program 8 refs, 8 figs, 13 tabs, 14 appendixes

  18. Illustration of Modern Wind Turbine Ancillary Services

    DEFF Research Database (Denmark)

    Margaris, Ioannis D.; Hansen, Anca Daniela; Sørensen, Poul Ejnar

    2010-01-01

    Increasing levels of wind power penetration in modern power systems has set intensively high standards with respect to wind turbine technology during the last years. Security issues have become rather critical and operation of wind farms as conventional power plants is becoming a necessity as wind...... turbines replace conventional units on the production side. This article includes a review of the basic control issues regarding the capability of the Doubly Fed Induction Generator (DFIG) wind turbine configuration to fulfill the basic technical requirements set by the system operators and contribute...

  19. Direct Drive Technology for Wind Turbine Applications

    OpenAIRE

    Azar, Ziad

    2014-01-01

    Siemens Wind Power have developed direct-drive (DD) wind turbine technology over the past decade to meet the future demand for cost effective and reliable onshore and offshore wind power. The increasing power requirements from the industry resulting in higher torque requirements in the drive train, has made it necessary to reduce the complexity and improve reliability of wind turbines by going to DD generator technology.

  20. Aeroelastic instability problems for wind turbines

    DEFF Research Database (Denmark)

    Hansen, Morten Hartvig

    2007-01-01

    This paper deals with the aeroelostic instabilities that have occurred and may still occur for modem commercial wind turbines: stall-induced vibrations for stall-turbines, and classical flutter for pitch-regulated turbines. A review of previous works is combined with derivations of analytical sta...... issues that represent unsolved aeroelostic instability problems for wind turbines. Copyright (c) 2007 John Wiley & Sons, Ltd.......This paper deals with the aeroelostic instabilities that have occurred and may still occur for modem commercial wind turbines: stall-induced vibrations for stall-turbines, and classical flutter for pitch-regulated turbines. A review of previous works is combined with derivations of analytical...... stability limits for typical blade sections that show the fundamental mechanisms of these instabilities. The risk of stall-induced vibrations is mainly related to blade airfoil characteristics, effective direction of blade vibrations and structural damping, whereas the blade tip speed, torsional blade...

  1. Airfoil characteristics for wind turbines

    DEFF Research Database (Denmark)

    Bak, C.; Fuglsang, P.; Sørensen, Niels N.

    1999-01-01

    is capable of determining the correct qualitative behaviour for airfoils subject to rotation. The method shows that lift is high at the root compared to 2D airfoil characteristics. Thedifferent systematic methods show the importance of rotational and 3D effects on rotors. Furthermore, the methods show high......Airfoil characteristics for use in the Blade Element Momentum (BEM) method calculating the forces on Horizontal Axis Wind Turbines (HAWT) are derived by use of systematic methods. The investigation and derivation of the airfoil characteristics are basedon four different methods: 1) Inverse momentum...... theory, 2) Actuator disc theory, 3) Numerical optimisation and 4) Quasi-3D CFD computations. The two former methods are based on 3D CFD computations and wind tunnel measurements on a 41-m full-scale rotorwith LM 19.1 blades. The derived airfoil characteristics show that the lift coefficient in stall...

  2. Design Mining Interacting Wind Turbines.

    Science.gov (United States)

    Preen, Richard J; Bull, Larry

    2016-01-01

    An initial study has recently been presented of surrogate-assisted evolutionary algorithms used to design vertical-axis wind turbines wherein candidate prototypes are evaluated under fan-generated wind conditions after being physically instantiated by a 3D printer. Unlike other approaches, such as computational fluid dynamics simulations, no mathematical formulations were used and no model assumptions were made. This paper extends that work by exploring alternative surrogate modelling and evolutionary techniques. The accuracy of various modelling algorithms used to estimate the fitness of evaluated individuals from the initial experiments is compared. The effect of temporally windowing surrogate model training samples is explored. A surrogate-assisted approach based on an enhanced local search is introduced; and alternative coevolution collaboration schemes are examined.

  3. Optimal Structural Reliability of Offshore Wind Turbines

    DEFF Research Database (Denmark)

    Sørensen, John Dalsgaard; Tarp-Johansen, N.J.

    2005-01-01

    structures, humans spent little time in the vicinity of offshore wind turbines and the probability of human injury during storm conditions is small. Further environmental pollution will also in general be small in case of failure. One could therefore argue that the reliability level of offshore wind turbines...

  4. Iterative feedback tuning of wind turbine controllers

    NARCIS (Netherlands)

    van Solingen, E.; Mulders, S.P.; van Wingerden, J.W.

    2017-01-01

    Traditionally, wind turbine controllers are designed using first principles or linearized or identified models. The aim of this paper is to show that with an automated, online, and model-free tuning strategy, wind turbine control performance can be significantly increased. For this purpose,

  5. Tjæreborg Wind Turbine (Esbjerg)

    DEFF Research Database (Denmark)

    Øye, Stig

    1991-01-01

    This paper presents the first measured timeseries for the Tjæreborg (Tjaereborg) Wind Turbine during operation with stepwise pitch angle changes.......This paper presents the first measured timeseries for the Tjæreborg (Tjaereborg) Wind Turbine during operation with stepwise pitch angle changes....

  6. Wind Turbine Aerodynamics from an Aerospace Perspective

    NARCIS (Netherlands)

    van Garrel, Arne; ten Pas, Sebastiaan; Venner, Cornelis H.; van Muijden, Jaap

    2018-01-01

    The current challenges in wind turbine aerodynamics simulations share a number of similarities with the challenges that the aerospace industry has faced in the past. Some of the current challenges in the aerospace aerodynamics community are also relevant for today’s wind turbine aerodynamics

  7. Virtual inertia for variable speed wind turbines

    DEFF Research Database (Denmark)

    Zeni, Lorenzo; Rudolph, Andreas Jakob; Münster-Swendsen, Janus

    2013-01-01

    Inertia provision for frequency control is among the ancillary services that different national grid codes will likely require to be provided by future wind turbines. The aim of this paper is analysing how the inertia response support from a variable speed wind turbine (VSWT) to the primary...

  8. Parametric study of composite wind turbine blades

    DEFF Research Database (Denmark)

    Kim, Taeseong; Branner, Kim; Hansen, Anders Melchior

    2011-01-01

    In this paper an anisotropic beam element for a composite wind turbine blades is developed. Eigenvalue analysis with the new beam element is conducted in order to understand its responses associated with the wind turbine performances. From the results of natural frequencies and mode shapes it is ...

  9. Voltage Quality of Grid Connected Wind Turbines

    DEFF Research Database (Denmark)

    Chen, Zhe; Blaabjerg, Frede; Sun, Tao

    2004-01-01

    Grid connected wind turbines may cause quality problems, such as voltage variation and flicker. This paper discusses the voltage variation and flicker emission of grid connected wind turbines with doubly-fed induction generators. A method to compensate flicker by using a voltage source converter...

  10. Reliability-Based Optimization of Wind Turbines

    DEFF Research Database (Denmark)

    Sørensen, John Dalsgaard; Tarp-Johansen, N.J.

    2004-01-01

    Reliability-based optimization of the main tower and monopile foundation of an offshore wind turbine is considered. Different formulations are considered of the objective function including benefits and building and failure costs of the wind turbine. Also different reconstruction policies in case...

  11. Dynamic Phase Compensation of wind turbines

    DEFF Research Database (Denmark)

    Soerensen, P.; Skaarup, J.; Iov, Florin

    2004-01-01

    This paper describes a dynamic phase compensation unit for a wind turbine with directly connected induction generators. The compensation unit is based on thyristor switched capacitors, where conventional wind turbine compensations use mechanical contactors to switch the capacitors. The unit modules...

  12. Wind turbines fundamentals, technologies, application, economics

    CERN Document Server

    Hau, Erich

    2013-01-01

    "Wind Turbines" addresses all those professionally involved in research, development, manufacture and operation of wind turbines. It provides a cross-disciplinary overview of modern wind turbine technology and an orientation in the associated technical, economic and environmental fields.  In its revised third edition, special emphasis has been given to the latest trends in wind turbine technology and design, such as gearless drive train concepts, as well as on new fields of application, in particular the offshore utilisation of wind energy. The author has gained experience over decades designing wind energy converters with a major industrial manufacturer and, more recently, in technical consulting and in the planning of large wind park installations, with special attention to economics.

  13. Lightning protection system for a wind turbine

    Science.gov (United States)

    Costin, Daniel P [Chelsea, VT; Petter, Jeffrey K [Williston, VT

    2008-05-27

    In a wind turbine (104, 500, 704) having a plurality of blades (132, 404, 516, 744) and a blade rotor hub (120, 712), a lightning protection system (100, 504, 700) for conducting lightning strikes to any one of the blades and the region surrounding the blade hub along a path around the blade hub and critical components of the wind turbine, such as the generator (112, 716), gearbox (708) and main turbine bearings (176, 724).

  14. Small-Signal Stability of Wind Power System With Full-Load Converter Interfaced Wind Turbines

    DEFF Research Database (Denmark)

    Knüppel, Thyge; Nielsen, Jørgen Nygaard; Jensen, Kim Høj

    2012-01-01

    Small-signal stability analysis of power system oscillations is a well established field within power system analysis, but not much attention has yet been paid to systems with a high penetration of wind turbines and with large wind power plants (WPP). In this paper a comprehensive analysis...... is presented which assesses the impact of full-load converter interfaced wind turbines on power system small-signal stability. The study is based on a 7 generator network with lightly damped inter-area modes. A detailed wind turbine (WT) model with all grid relevant control functions is used in the study...

  15. 'Wind turbine syndrome': fact or fiction?

    Science.gov (United States)

    Farboud, A; Crunkhorn, R; Trinidade, A

    2013-03-01

    Symptoms, including tinnitus, ear pain and vertigo, have been reported following exposure to wind turbine noise. This review addresses the effects of infrasound and low frequency noise and questions the existence of 'wind turbine syndrome'. This review is based on a search for articles published within the last 10 years, conducted using the PubMed database and Google Scholar search engine, which included in their title or abstract the terms 'wind turbine', 'infrasound' or 'low frequency noise'. There is evidence that infrasound has a physiological effect on the ear. Until this effect is fully understood, it is impossible to conclude that wind turbine noise does not cause any of the symptoms described. However, many believe that these symptoms are related largely to the stress caused by unwanted noise exposure. There is some evidence of symptoms in patients exposed to wind turbine noise. The effects of infrasound require further investigation.

  16. Computational Aerodynamics and Aeroacoustics for Wind Turbines

    DEFF Research Database (Denmark)

    Shen, Wen Zhong

    To analyse the aerodynamic performance of wind turbine rotors, the main tool in use today is the 1D-Blade Element Momentum (BEM) technique combined with 2D airfoil data. Because of its simplicity, the BEM technique is employed by industry when designing new wind turbine blades. However, in order...... to obtain more detailed information of the flow structures and to determine more accurately loads and power yield of wind turbines or cluster of wind turbines, it is required to resort to more sophisticated techniques, such as Computational Fluid Dynamics (CFD). As computer resources keep on improving year...... by year (about ten times every five years from statistics over the last twenty years), CFD has now become a popular tool for studying the aerodynamics of wind turbines. The present thesis consists of 19 selected papers dealing with the development and use of CFD methods for studying the aerodynamics...

  17. Rotating transformers in wind turbine applications

    Energy Technology Data Exchange (ETDEWEB)

    Hylander, J. [Chalmers Univ. of Technology, Goeteborg (Sweden); Engstroem, S. [Aegir konsult AB, Lidingoe (Sweden)

    1996-12-01

    The power consumption of rotating electrical components is often supplied via slip-rings in wind turbines. Slip-ring equipment is expensive and need maintenance and are prone to malfunction. If the slip-rings could be replaced with contact-less equipment better turbines could be designed. This paper presents the design, some FE calculations and some measurements on a prototype rotating transformer. The proposed transformer consists of a secondary rotating winding and a stationary exciting primary winding. The results indicate that this transformer could be used to replace slip-rings in wind turbines. 4 refs, 3 figs

  18. Impact of a wind turbine on turbulence: Un-freezing turbulence by means of a simple vortex particle approach

    DEFF Research Database (Denmark)

    Branlard, Emmanuel Simon Pierre; Mercier, P.; Machefaux, Ewan

    2016-01-01

    the insertion point. The presence of the wind turbine and its wake is found to have insignificant effect on upstream turbulence. Finally, the mean velocity profiles in the wake are found to be in good agreement with both lidar measurements and CFD simulations. (C) 2016 Elsevier Ltd. All rights reserved....

  19. Understanding Trends in Wind Turbine Prices Over the Past Decade

    Energy Technology Data Exchange (ETDEWEB)

    Bolinger, Mark; Wiser, Ryan

    2011-10-26

    Taking a bottom-up approach, this report examines seven primary drivers of wind turbine prices in the United States, with the goal of estimating the degree to which each contributed to the doubling in turbine prices from 2002 through 2008, as well as the subsequent decline in prices through 2010 (our analysis does not extend into 2011 because several of these drivers are best gauged on a full-year basis due to seasonality issues). The first four of these drivers can be considered, at least to some degree, endogenous influences – i.e., those that are largely within the control of the wind industry – and include changes in: 1) Labor costs, which have historically risen during times of tight turbine supply; 2) Warranty provisions, which reflect technology performance and reliability, and are most often capitalized in turbine prices; 3) Turbine manufacturer profitability, which can impact turbine prices independently of costs; and 4) Turbine design, which for the purpose of this analysis is principally manifested through increased turbine size. The other three drivers analyzed in this study can be considered exogenous influences, in that they can impact wind turbine costs but fall mostly outside of the direct control of the wind industry. These exogenous drivers include changes in: 5) Raw materials prices, which affect the cost of inputs to the manufacturing process; 6) Energy prices, which impact the cost of manufacturing and transporting turbines; and 7) Foreign exchange rates, which can impact the dollar amount paid for turbines and components imported into the United States.

  20. Adaptive Extremum Control and Wind Turbine Control

    DEFF Research Database (Denmark)

    Ma, Xin

    1997-01-01

    This thesis is divided into two parts, i.e., adaptive extremum control and modelling and control of a wind turbine. The rst part of the thesis deals with the design of adaptive extremum controllers for some processes which have the behaviour that process should have as high e ciency as possible...... in parameters, and thus directly lends itself to parameter estimation and adaptive control. The extremum control law is derived based on static optimization of a performance function. For a process with nonlinearity at output the intermediate signal between the linear part and nonlinear part plays an important...... role. If it can be emphasis on control design. The models have beenvalidated by experimental data obtained from an existing wind turbine. The e ective wind speed experienced by the rotor of a wind turbine, which is often required by some control methods, is estimated by using a wind turbine as a wind...

  1. Illustration of Modern Wind Turbine Ancillary Services

    Directory of Open Access Journals (Sweden)

    Ioannis D. Margaris

    2010-06-01

    Full Text Available Increasing levels of wind power penetration in modern power systems has set intensively high standards with respect to wind turbine technology during the last years. Security issues have become rather critical and operation of wind farms as conventional power plants is becoming a necessity as wind turbines replace conventional units on the production side. This article includes a review of the basic control issues regarding the capability of the Doubly Fed Induction Generator (DFIG wind turbine configuration to fulfill the basic technical requirements set by the system operators and contribute to power system security. An overview of ancillary services provided by wind turbine technology nowadays is provided, i.e., fault ride-through capability, reactive power supply and frequency-active power control.

  2. Flicker emission levels from wind turbines

    International Nuclear Information System (INIS)

    Soerensen, P.; Tande, J.O.; Soendergaard, L.M.

    1996-01-01

    The paper presents and verifies a method to calculate the flicker emission levels from wind turbines connected to power distribution systems. The idea of the method is to measure the flicker emission level from a wind turbine with reference conditions and to use these measurements to calculate a flicker coefficient for that specific wind turbine type. This can be done as a part of the approval of a wind turbine type. The flicker coefficient can then be used to calculate the flicker emission level from any wind turbine of that type with any grid and wind conditions. A simple method to determine the total flicker emission level from a number of wind turbines is also presented and verified. The flicker coefficient method is applied to 4 Danish wind turbine types representing stall and pitch control and nominal power from 300 kW to 500 kW. The conclusion is that the flicker emission in certain cases exceeds limits which are expected to be normative in the future. (author)

  3. Meteorological aspects of siting large wind turbines

    Energy Technology Data Exchange (ETDEWEB)

    Hiester, T.R.; Pennell, W.T.

    1981-01-01

    This report, which focuses on the meteorological aspects of siting large wind turbines (turbines with a rated output exceeding 100 kW), has four main goals. The first is to outline the elements of a siting strategy that will identify the most favorable wind energy sites in a region and that will provide sufficient wind data to make responsible economic evaluations of the site wind resource possible. The second is to critique and summarize siting techniques that were studied in the Department of Energy (DOE) Wind Energy Program. The third goal is to educate utility technical personnel, engineering consultants, and meteorological consultants (who may have not yet undertaken wind energy consulting) on meteorological phenomena relevant to wind turbine siting in order to enhance dialogues between these groups. The fourth goal is to minimize the chances of failure of early siting programs due to insufficient understanding of wind behavior.

  4. Aerodynamic damping of nonlinearily wind-excited wind turbine blades

    NARCIS (Netherlands)

    Van der Male, P.; Van Dalen, K.N.; Metrikine, A.

    2013-01-01

    This paper presents the first step of the derivation of an aerodynamic damping matrix that can be adopted for the foundation design of a wind turbine. A single turbine blade is modelled as a discrete mass-spring system, representing the flap and edge wise motions. Nonlinear wind forcing is applied,

  5. Offshore wind turbines reliability, availability and maintenance

    CERN Document Server

    Tavner, Peter

    2012-01-01

    The first book to specifically focus on offshore wind turbine technology and which addresses practically wind turbine reliability and availability. The book draws on the author's experience of power generation reliability and availability and the condition monitoring of that plant to describe the problems facing the developers of offshore wind farms and the solutions available to them to raise availability, reduce cost of energy and improve through life cost.

  6. Rain erosion of wind turbine blade coatings using discrete water jets: Effects of water cushioning, substrate geometry, impact distance, and coating properties

    DEFF Research Database (Denmark)

    Zhang, Shizhong; Dam-Johansen, Kim; Bernad, Pablo L.

    2015-01-01

    Rapid and reliable rain erosion screening of blade coatings for wind turbines is a strong need in the coatings industry. One possibility in this direction is the use of discrete water jets, where so-called jet slugs are impacted on a coating surface. Previous investigations have mapped the influe......Rapid and reliable rain erosion screening of blade coatings for wind turbines is a strong need in the coatings industry. One possibility in this direction is the use of discrete water jets, where so-called jet slugs are impacted on a coating surface. Previous investigations have mapped......, impact, hardness, and abrasion experiments, were also conducted. The ranking of abrasion resistance of the blade coatings was in agreement with the ranking of rain erosion resistance measured in the whirling arm rig (an industrial standard).Results of this work, with more pertinent parameters explored...

  7. Assessing the Impacts of Reduced Noise Operations of Wind Turbines on Neighbor Annoyance: A Preliminary Analysis in Vinalhaven, Maine

    Energy Technology Data Exchange (ETDEWEB)

    Hoen, Ben; Wiser, Ryan; Eckholdt, Haftan

    2010-06-23

    Neighbors living near the 3 turbine, 4.5 MW Vinalhaven, Maine wind power facility, which began operations in late 2009, have complained that the noise from the turbines is unwelcome and annoying. Fox Islands Wind, the owner of the facility, hypothesized that implementing a Noise Reduced Operation (NRO) for the turbines, which effectively limits the turbines maximum rpm and power output, would reduce the sound levels produced by the turbines, and therefore might also reduce the degree to which the neighbors report being annoyed by those sounds. To test this hypothesis in a preliminary fashion, a pilot study was conducted in early 2010, the results of which are the subject of this brief report. The study included asking near-by residents - those within roughly 3000 feet - to rate the sounds and the degree to which they were annoyed by them using logs which they filled out at multiple times during the day on as many days as were possible in the 35 day study period in February and March, 2010. Meanwhile, FIW adjusted the NRO settings of the turbines in a random fashion in the evenings during the same period, but in a pattern that the respondents were not made aware of. Ultimately, nine individuals turned in roughly 200 log entries (i.e., responses), each of which was time coded to allow testing if the response was correlated with the wind facility operating conditions at that time. The analysis of these data found small, non-statistically-significant differences in self-reported turbine loudness and annoyance ratings between the periods when the NRO was enacted and when it was not, after controlling for many of the relationships that could independently influence perceived loudness and annoyance (e.g., wind direction, time of day). Possible explanations for these small differences in self-reported turbine loudness and annoyance ratings include: the relative difference in sound output from the turbines when NRO was engaged and when it was not was small; and/or that

  8. A Two-Bladed Concept Wind Turbine

    DEFF Research Database (Denmark)

    Kim, Taeseong

    2012-01-01

    This article shows the potential for reducing extreme loads with an innovative design of wind turbine, a partial pitch two-bladed concept turbine. The most extreme conditions to test a turbine are considered to be stand-still combined with a grid failure in which the wind comes from all directions...... from 0 to 360 degrees. All aeroelastic load simulations are done by using the aeroelastic code HAWC2. From the load comparisons between the partial pitch two-bladed turbine and a conventional three-bladed turbine it is observed that the partial pitch two-bladed turbine can reduce the extreme tower...... bottom bending moment by approximately 33% compared to the three-bladed turbine....

  9. Modelling and control of variable speed wind turbines for power system studies

    DEFF Research Database (Denmark)

    Michalke, Gabriele; Hansen, Anca Daniela

    2010-01-01

    and implemented in the power system simulation tool DIgSILENT. Important issues like the fault ride-through and grid support capabilities of these wind turbine concepts are addressed. The paper reveals that advanced control of variable speed wind turbines can improve power system stability. Finally......, it will be shown in the paper that wind parks consisting of variable speed wind turbines can help nearby connected fixed speed wind turbines to ride-through grid faults. Copyright © 2009 John Wiley & Sons, Ltd.......Modern wind turbines are predominantly variable speed wind turbines with power electronic interface. Emphasis in this paper is therefore on the modelling and control issues of these wind turbine concepts and especially on their impact on the power system. The models and control are developed...

  10. Frequency Based Fault Detection in Wind Turbines

    DEFF Research Database (Denmark)

    Odgaard, Peter Fogh; Stoustrup, Jakob

    2014-01-01

    In order to obtain lower cost of energy for wind turbines fault detection and accommodation is important. Expensive condition monitoring systems are often used to monitor the condition of rotating and vibrating system parts. One example is the gearbox in a wind turbine. This system is operated...... in parallel to the control system, using different computers and additional often expensive sensors. In this paper a simple filter based algorithm is proposed to detect changes in a resonance frequency in a system, exemplified with faults resulting in changes in the resonance frequency in the wind turbine...... turbine fault detection and fault tolerant control benchmark model, in which one of the included faults results in a change in the gear box resonance frequency. This evaluation shows the potential of the proposed scheme to monitor the condition of wind turbine gear boxes in the existing control system....

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

    DEFF Research Database (Denmark)

    Feng, Ju; Shen, 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...

  12. Structural Dynamic Behavior of Wind Turbines

    Science.gov (United States)

    Thresher, Robert W.; Mirandy, Louis P.; Carne, Thomas G.; Lobitz, Donald W.; James, George H. III

    2009-01-01

    The structural dynamicist s areas of responsibility require interaction with most other members of the wind turbine project team. These responsibilities are to predict structural loads and deflections that will occur over the lifetime of the machine, ensure favorable dynamic responses through appropriate design and operational procedures, evaluate potential design improvements for their impact on dynamic loads and stability, and correlate load and control test data with design predictions. Load prediction has been a major concern in wind turbine designs to date, and it is perhaps the single most important task faced by the structural dynamics engineer. However, even if we were able to predict all loads perfectly, this in itself would not lead to an economic system. Reduction of dynamic loads, not merely a "design to loads" policy, is required to achieve a cost-effective design. The two processes of load prediction and structural design are highly interactive: loads and deflections must be known before designers and stress analysts can perform structural sizing, which in turn influences the loads through changes in stiffness and mass. Structural design identifies "hot spots" (local areas of high stress) that would benefit most from dynamic load alleviation. Convergence of this cycle leads to a turbine structure that is neither under-designed (which may result in structural failure), nor over-designed (which will lead to excessive weight and cost).

  13. Wind tunnel tests of a free yawing downwind wind turbine

    DEFF Research Database (Denmark)

    Verelst, David Robert; Larsen, Torben J.; van Wingerden, Jan-Willem

    2014-01-01

    . The discussed test cases show that the turbine is stable while operating in free yawing conditions. Further, the effect of the tower shadow passage on the blade flapwise strain measurement is evaluated. Finally, data from the experiment is compared with preliminary simulations using DTU Wind Energy......This research paper presents preliminary results on a behavioural study of a free yawing downwind wind turbine. A series of wind tunnel tests was performed at the TU Delft Open Jet Facility with a three bladed downwind wind turbine and a rotor radius of 0.8 meters. The setup includes an off...

  14. Wind Turbine Manufacturers in the United States: Locations and Local Impacts (Presentation)

    Energy Technology Data Exchange (ETDEWEB)

    Tegen, S.

    2010-05-26

    Suzanne Tegen's presentation about U.S. wind energy manufacturing (presented at WINDPOWER 2010 in Dallas) provides information about challenges to modeling renewables; wind energy's economic "ripple effect"; case studies about wind-related manufacturing in Colorado, Iowa, Ohio, and Indiana; manufacturing maps for the Great Lakes region, Arkansas, and the United States; sample job announcements; and U.S. Treasury Grant 1603 funding.

  15. Flow separation on wind turbines blades

    Science.gov (United States)

    Corten, G. P.

    2001-01-01

    separation line, which causes the terms with the chord-wise speed or accelerations to disappear. The conclusion is that the chord-wise pressure gradient balances the Coriolis force. By doing so we obtain a simple set of equations that can be solved analytically. Subsequently, our model predicts that the convective term with the radial velocity (vrvr/r) is dominant in the equation for the r-direction, precisely the term that was neglected in Snel's analysis. 3. Multiple Power Levels Several large commercial wind turbines demonstrate drops in maximum power levels up to 45%, under apparently equal conditions. Earlier studies attempting to explain this effect by technical malfunctioning, aerodynamic instabilities and blade contamination effects estimated with computational fluid dynamics, have not yet yielded a plausible result. We formulated many hypotheses, three of which were useful. By taking stall flag measurements and making two other crucial experiments, we could confirm one of those three hypotheses: the insect hypothesis. Insects only fly in low wind, impacting upon the blades at specific locations. In these conditions, the insectual remains are located at positions where roughness has little influence on the profile performance, so that the power is not affected. In high winds however, the flow around the blades has changed. As a result, the positions at which the insects have impacted at low winds are very sensitive to contamination. So the contamination level changes at low wind when insects fly and this level determines the power in high winds when insects do not fly. As a consequence we get discrete power levels in high winds. The other two hypotheses, which did not cause the multiple power levels for the case we studied, gave rise to two new insights. First, we expect the power to depend on the wind direction at sites where the shape of the terrain concentrates the wind. In this case the power level of all turbine types, including pitch regulated ones, will be

  16. Reliability Modeling of Wind Turbines

    DEFF Research Database (Denmark)

    Kostandyan, Erik

    components. Thus, models of reliability should be developed and applied in order to quantify the residual life of the components. Damage models based on physics of failure combined with stochastic models describing the uncertain parameters are imperative for development of cost-optimal decision tools...... for Operation & Maintenance planning. Concentrating efforts on development of such models, this research is focused on reliability modeling of Wind Turbine critical subsystems (especially the power converter system). For reliability assessment of these components, structural reliability methods are applied....... Further, reliability modeling of load sharing systems is considered and a theoretical model is proposed based on sequential order statistics and structural systems reliability methods. Procedures for reliability estimation are detailed and presented in a collection of research papers....

  17. Probabilistic Modeling of Wind Turbine Drivetrain Components

    DEFF Research Database (Denmark)

    Rafsanjani, Hesam Mirzaei

    Wind energy is one of several energy sources in the world and a rapidly growing industry in the energy sector. When placed in offshore or onshore locations, wind turbines are exposed to wave excitations, highly dynamic wind loads and/or the wakes from other wind turbines. Therefore, most componen....../nodules on fatigue life of cast iron samples. The cast iron samples scanned by 3D tomography equipment at the DTU Wind Energy (Risø campus), and the distribution of nodules are used to estimate the fatigue life....

  18. European wind turbine standards 2 (EWTS-2)

    Energy Technology Data Exchange (ETDEWEB)

    Pierik, J.T.G.; Dekker, J.W.M.; Braam, H. [and others

    1999-03-01

    A summary is given of the main results of the European Wind Turbine Standards II project. EWTS-II was completed in 1998 and included investigations on: 1) wind farms-wind field and turbine loading; 2) complex terrain and fatigue loading; 3) extreme wind conditions; 4) quantification of failure probabilities; 5) integration of blade tests in design; 6) power performance in complex terrain; 7) site evaluation. In addition to these scientific evaluations, the EWTS-II participants established an organization of qualified measuring institute in the field of wind energy, the MEASNET organization. MEASNET unified measurement procedures of the participating institutes and guarantees qualified measurements and mutual acceptance among its members. (LN)

  19. Stochastic wind turbine control in multiblade coordinates

    DEFF Research Database (Denmark)

    Thomsen, Sven Creutz; Niemann, Hans Henrik; Poulsen, Niels Kjølstad

    2010-01-01

    pitch controller design. In this way the variability of the wind can be estimated and compensated for by the controller. The wind turbine model is in general time-variant due to its rotational nature. For this reason the modeling and control is carried out in so-called multiblade coordinates......In this paper we consider wind turbine load attenuation through model based control. Asymmetric loads caused by the wind field can be reduced by pitching the blades individually. To this end we investigate the use of stochastic models of the wind which can be included in a model based individual...

  20. Active load control techniques for wind turbines.

    Energy Technology Data Exchange (ETDEWEB)

    van Dam, C.P. (University of California, Davis, CA); Berg, Dale E.; Johnson, Scott J. (University of California, Davis, CA)

    2008-07-01

    This report provides an overview on the current state of wind turbine control and introduces a number of active techniques that could be potentially used for control of wind turbine blades. The focus is on research regarding active flow control (AFC) as it applies to wind turbine performance and loads. The techniques and concepts described here are often described as 'smart structures' or 'smart rotor control'. This field is rapidly growing and there are numerous concepts currently being investigated around the world; some concepts already are focused on the wind energy industry and others are intended for use in other fields, but have the potential for wind turbine control. An AFC system can be broken into three categories: controls and sensors, actuators and devices, and the flow phenomena. This report focuses on the research involved with the actuators and devices and the generated flow phenomena caused by each device.

  1. Modelling Wind Turbine Inflow: The Induction Zone

    DEFF Research Database (Denmark)

    Meyer Forsting, Alexander Raul

    to the rotor, but requires exact knowledge of the flow deceleration to estimate the available, undis- turbed kinetic energy. Thus this thesis explores, mostly numerically, any wind turbine or environmental dependencies of this deceleration. The computational fluid dynamics model (CFD) employed is validated......A wind turbine decelerates the wind in front of its rotor by extracting kinetic energy. The wind speed reduction is maximal at the rotor and negligible more than five rotor radii upfront. By measuring wind speed this far from the rotor, the turbine’s performance is determined without any rotor bias...... significant parameter. Exploiting this singu- lar dependency, a fast semi-empirical model is devised that accurately predicts the velocity deficit upstream of a single turbine. Near-rotor mea-surements in combination with this model are able to retrieve the kinetic energy available to the turbine in flat...

  2. Innovative Design of Vertical Axis Wind Turbine

    DEFF Research Database (Denmark)

    Chougule, Prasad

    2013-01-01

    The wind turbines can be classified as: i) Horizontal axis wind turbines (HAWT), and ii) Vertical axis wind turbines (VAWT). The HAWT is fully developed and the size is growing higher. Whereas, the VAWT is not developed because of the less efficiency and vibration issues of big structure. However......, and its aerodynamic characteristics are obtained by an experimental method. A new design is called D2퐴 − 푉퐴푊푇 and a test ring is made to validate the numerical results. A double multiple stream tube method (DMSTM) and blade element method (BEM) are used to determine the numerical performance of a proposed...

  3. On System Identification of Wind Turbines

    DEFF Research Database (Denmark)

    Kirkegaard, Poul Henning; Perisic, Nevena; Pedersen, B.J.

    Recently several methods have been proposed for the system identification of wind turbines which can be considered as a linear time-varying system due to the operating conditions. For the identification of linear wind turbine models, either black-box or grey-box identification can be used....... The operational model analysis (OMA) methodology can provide accurate estimates of the natural frequencies, damping ratios and mode shapes of the systems as long as the measurements have a low noise to signal ratio. However, in order to take information about the wind turbine into account a grey...

  4. Wind Turbine Power Curves Incorporating Turbulence Intensity

    DEFF Research Database (Denmark)

    Sørensen, Emil Hedevang Lohse

    2014-01-01

    The performance of a wind turbine in terms of power production (the power curve) is important to the wind energy industry. The current IEC-61400-12-1 standard for power curve evaluation recognizes only the mean wind speed at hub height and the air density as relevant to the power production...

  5. Impact of the Diurnal Cycle of the Atmospheric Boundary Layer on Wind-Turbine Wakes: A Numerical Modelling Study

    Science.gov (United States)

    Englberger, Antonia; Dörnbrack, Andreas

    2018-03-01

    The wake characteristics of a wind turbine for different regimes occurring throughout the diurnal cycle are investigated systematically by means of large-eddy simulation. Idealized diurnal cycle simulations of the atmospheric boundary layer are performed with the geophysical flow solver EULAG over both homogeneous and heterogeneous terrain. Under homogeneous conditions, the diurnal cycle significantly affects the low-level wind shear and atmospheric turbulence. A strong vertical wind shear and veering with height occur in the nocturnal stable boundary layer and in the morning boundary layer, whereas atmospheric turbulence is much larger in the convective boundary layer and in the evening boundary layer. The increased shear under heterogeneous conditions changes these wind characteristics, counteracting the formation of the night-time Ekman spiral. The convective, stable, evening, and morning regimes of the atmospheric boundary layer over a homogeneous surface as well as the convective and stable regimes over a heterogeneous surface are used to study the flow in a wind-turbine wake. Synchronized turbulent inflow data from the idealized atmospheric boundary-layer simulations with periodic horizontal boundary conditions are applied to the wind-turbine simulations with open streamwise boundary conditions. The resulting wake is strongly influenced by the stability of the atmosphere. In both cases, the flow in the wake recovers more rapidly under convective conditions during the day than under stable conditions at night. The simulated wakes produced for the night-time situation completely differ between heterogeneous and homogeneous surface conditions. The wake characteristics of the transitional periods are influenced by the flow regime prior to the transition. Furthermore, there are different wake deflections over the height of the rotor, which reflect the incoming wind direction.

  6. Wind Turbines Adaptation to the Variability of the Wind Field

    Science.gov (United States)

    Ulianov, Yuriy; Martynenko, Gennadii; Misaylov, Vitaliy; Soliannikova, Iuliia

    2010-05-01

    WIND TURBINES ADAPTATION TO THE VARIABILITY OF THE WIND FIELD The subject of our scientific research is wind power turbines (WPT) with the horizontal axis which were now common in the world. Efficient wind turbines work is largely determined by non-stationarity of the wind field, expressed in its gustiness, the presence of vertical and horizontal shifts of wind speed and direction. At critical values of the wind parameters WPT has aerodynamic and mechanical overload, leading to breakdowns, premature wear and reduce the life of the wind turbine. To prevent accidents at the peak values of wind speed it is used the regulatory system of windwheels. WPT control systems provide a process orientation of the wind turbine rotor axis in the line of the mean wind. Wind turbines are also equipped with braking device used to protect against breakdowns when a significant increase in the wind. In general, all these methods of regulation are not always effective. Thus, in practice there may be situations when the wind speed is many times greater than the stated limit. For example, if there are microbursts in the atmospheric boundary layer, low-level wind shears caused by its gust front, storms, etc. It is required for a wind power turbine adaptation to intensive short-term wind impulses and considerable vertical wind shifts that the data about them shall be obtained ahead of time. To do this it is necessary to have the information on the real structure of the wind field in the area of the blade sweep for the minimum range against the wind that is determined by the mean speed and the system action time. The implementation of acoustic and laser traditional wind sounding systems is limited by ambient acoustic noise, by heavy rain, snowfall and by fog. There are free of these disadvantages the inclined radioacoustic sounding (IRASS) technique which works for a system of remote detection and control of wind gusts. IRASS technique is realized as low-potential Doppler pulse radar

  7. Wind turbine assisted diesel generator systems

    Science.gov (United States)

    Schienbein, L. A.

    1981-12-01

    The need to reduce the cost of energy in remote communities served by diesel generators has led to the investigation of the use of wind energy to replace some or all of the fuel consumed. The development of wind-turbine-assisted diesel generators in Canada has progressed from the design and testing of a 12-kW unit to the design of a prototype 100-kW wind turbine diesel hybrid. This paper presents the results of the 12-kW tests and the implementation of the test results, and the results of further engineering and cost analyses in the design of a prototype 100-kW wind turbine diesel hybrid system. The value of wind energy in a wind turbine diesel hybrid is greatly improved if the diesel generator system itself is designed to operate more efficiently at part load, with or without wind power assistance. Excess wind energy and wind turbine power fluctuations (which result in voltage and frequency fluctuations) can be minimized by selecting the best rotor operating speed.

  8. Simulation of a flexible wind turbine response to a grid fault

    DEFF Research Database (Denmark)

    Hansen, Anca Daniela; Cutululis, Nicolaos Antonio; Sørensen, Poul Ejnar

    2007-01-01

    The purpose of this work is to illustrate the impact of a grid fault on the mechanical loads of a wind turbine. Grid faults generate transients in the generator electromagnetic torque, which are propagated in the wind turbine, stressing its mechanical components. Grid faults are normally simulated...... in power system simulation tools applying simplified mechanical models of the drive train. This paper presents simulations of the wind turbine load response to grid faults with an advanced aeroelastic computer code (HAWC2). The core of this code is an advanced model for the flexible structure of the wind...... turbines, taking the flexibility of the tower, blades and other components of the wind turbines into account. The effect of a grid fault on the wind turbine flexible structure is assessed for a typical fixed speed wind turbine, equipped with an induction generator....

  9. Wind turbine noise modeling : a comparison of modeling methods

    International Nuclear Information System (INIS)

    Wang, L.; Strasser, A.

    2009-01-01

    All wind turbine arrays must undergo a noise impact assessment. DataKustik GmbH developed the Computer Aided Noise Abatement (Cadna/A) modeling software for calculating noise propagation to meet accepted protocols and international standards such as CONCAWE and ISO 9613 standards. The developer of Cadna/A, recommended the following 3 models for simulating wind turbine noise. These include a disk of point sources; a ring of point sources located at the tip of each blade; and a point source located at the top of the wind turbine tower hub. This paper presented an analytical comparison of the 3 models used for a typical wind turbine with a hub tower containing 3 propeller blades, a drive-train and top-mounted generator, as well as a representative wind farm, using Cadna/A. AUC, ISO and IEC criteria requirements for the meteorological input with Cadna/A for wind farm noise were also discussed. The noise predicting modelling approach was as follows: the simplest model, positioning a single point source at the top of the hub, can be used to predict sound levels for a typical wind turbine if receptors are located 250 m from the hub; a-weighted sound power levels of a wind turbine at cut-in and cut-off wind speed should be used in the models; 20 by 20 or 50 by 50 meter terrain parameters are suitable for large wind farm modeling; and ISO 9613-2 methods are recommended to predict wind farm noise with various metrological inputs based on local conditions. The study showed that the predicted sound level differences of the 3 wind turbine models using Cadna/A are less than 0.2 dB at receptors located greater than 250 m from the wind turbine hub, which fall within the accuracy range of the calculation method. All 3 models of wind turbine noise meet ISO9613-2 standards for noise prediction using Cadna/A. However, the single point source model was found to be the most efficient in terms of modeling run-time among the 3 models. 7 refs., 3 tabs., 15 figs.

  10. Wind technology development: Large and small turbines

    Science.gov (United States)

    Thresher, R. W.; Hock, S. M.; Loose, R. R.; Goldman, P.

    1994-12-01

    Wind technology has developed rapidly over the last decade with the design and development of advanced systems with improved performance, higher reliability, and lower costs. During the past several years, substantial gains have been made in wind turbine designs, lowering costs to an average of $0.05/kWh while further technology development is expected to allow the cost to drop below $0.04/kWh by 2000. As a result, wind is expected to be one of the least expensive forms of new electric generation in the next century. This paper will present the technology developments for both utility-scale wind turbines and remote, small-village wind turbines that are currently available or in development. Technology innovations are being adapted for remote and stand-alone power applications with smaller wind turbines. Hybrid power systems using smaller 1 to 50 (kW) wind turbines are being developed for non-grid-connected electrical generation applications. These village power systems typically use wind energy, photovoltaics, battery storage, and conventional diesel generators to power remote communities. Smaller turbines are being explored for application as distributed generation sources on utility grids to supply power during periods of peak demand, avoiding costly upgrades in distribution equipment. New turbine designs now account for turbulence-induced loads, unsteady aerodynamic stall effects, and complex fatigue loads, making use of new technology developments such as advanced airfoils. The new airfoils increase the energy capture, improve the operating efficiency, and reduce the sensitivity of the airfoils to operation roughness. Electronic controls are allowing variable rotor speed operation; while aerodynamic control devices, such as ailerons and flaps, are used to modulate power or stop the rotor in high-speed conditions. These technology trends and future turbine configurations are being sponsored and explored by the U.S. Department of Energy's Wind Energy Program.

  11. LES investigation of infinite staggered wind-turbine arrays

    International Nuclear Information System (INIS)

    Yang, Xiaolei; Sotiropoulos, Fotis

    2014-01-01

    The layouts of turbines affect the turbine wake interactions and thus the wind farm performance. The wake interactions in infinite staggered wind-turbine arrays are investigated and compared with infinite aligned turbine arrays in this paper. From the numerical results we identify three types of wake behaviours, which are significantly different from wakes in aligned wind-turbine arrays. For the first type, each turbine wake interferes with the pair of staggered downstream turbine wakes and the aligned downstream turbine. For the second type, each turbine wake interacts with the first two downstream turbine wakes but does not show significant interference with the second aligned downstream turbine. For the third type, each turbine wake recovers immediately after passing through the gap of the first two downstream turbines and has little interaction with the second downstream turbine wakes The extracted power density and power efficiency are also studied and compared with aligned wind-turbine arrays

  12. Effects of wind turbines on human health and environment

    Energy Technology Data Exchange (ETDEWEB)

    Ramanan, G. [RV College of Engineering, Bangalore (India); Pandian, A.; Gowda, G.; Raghunandan, A. [MS RAMAIAH Institute of Technology, Bangalore (India)

    2012-07-01

    The impact of climate change through global warming has been a concern for some time now. Targets are being set for ratifying countries to reduce their CO{sup 2} emissions. In order to achieve reduction in CO{sup 2} emissions, there must be sustained move in the production of electricity from renewable sources other than fossil fuel combustion. Of the renewable energy sources, the most realistic and economic is Wind Power. The Asian continent is developing into one of the main powerhouses of Wind Energy. The strongest market leader in Wind Energy in the continent is India. On the flip side, there are some effects of Wind Turbines which are hazardous to human health like noise generated. Such hazards are also likely and known to affect the migratory birds during transition. This paper will address the effects of Wind Turbine on Human Health and Environment. The paper will focus on the following questions: (1)What are the potential health and environmental impacts of Wind Turbines? (2)How is exposure to Wind Turbine Noise assessed? (3)What consultation process with the community is required before Wind Farms are constructed? (Author)

  13. Improved diffuser for augmenting a wind turbine

    Science.gov (United States)

    Foreman, K.M.; Gilbert, B.L.

    A diffuser for augmenting a wind turbine having means for energizing the boundary layer at several locations along the diffuser walls is improved by the addition of a short collar extending radially outward from the outlet of the diffuser.

  14. Proceedings: Small Wind Turbine Systems, 1981

    Energy Technology Data Exchange (ETDEWEB)

    1981-01-01

    Small wind turbine technology is discussed. Systems development, test programs, utility interface issues, safety and reliability programs, applications, and marketing are discussed. For individual titles, see N83-23723 through N83-23741.

  15. Wind Turbine Drivetrain Condition Monitoring - An Overview

    Energy Technology Data Exchange (ETDEWEB)

    Sheng, S; Veers, P.

    2011-10-01

    This paper provides an overview of wind turbine drivetrain condition monitoring based on presentations from a condition monitoring workshop organized by the National Renewable Energy Laboratory in 2009 and on additional references.

  16. Adhesive Joints in Wind Turbine Blades

    DEFF Research Database (Denmark)

    Jørgensen, Jeppe Bjørn

    The industrial goal of this PhD project is to enable manufacturing of larger wind turbine blades by improving the existing design methods for adhesive joints. This should improve the present joint design such that more efficient wind turbine blades can be produced. The main scientific goal...... of the project is to develop new- and to improve the existing design rules for adhesive joints in wind turbine blades. The first scientific studies of adhesive joints were based on stress analysis, which requires that the bond-line is free of defects, but this is rarely the case for a wind turbine blade. Instead...... curing and test temperatures) on the formation of transverse cracks in the adhesive were tested experimentally. It was assumed that the transverse cracks evolved due to a combination of mechanical- and residual stresses in the adhesive. A new approach was developed that allows the residual stress...

  17. Investigation of Wind Turbine Rotor Concepts for Offshore Wind Farms

    International Nuclear Information System (INIS)

    Ceyhan, Özlem; Grasso, Francesco

    2014-01-01

    Current plans in offshore wind energy developments call for further reduction of cost of energy. In order to contribute to this goal, several wind turbine rotor concepts have been investigated. Assuming the future offshore wind turbines will operate only in the offshore wind farms, the rotor concepts are not only evaluated for their stand-alone performances and their potential in reducing the loads, but also for their performance in an offshore wind farm. In order to do that, the 10MW reference wind turbine designed in Innwind.EU project is chosen as baseline. Several rotor parameters have been modified and their influences are investigated for offshore wind turbine design purposes. This investigation is carried out as a conceptual parametrical study. All concepts are evaluated numerically with BOT (Blade optimisation tool) software in wind turbine level and with Farmflow software in wind farm level for two wind farm layouts. At the end, all these concepts are compared with each other in terms of their advantages and disadvantages

  18. Simplified formulae for the estimation of offshore wind turbines clutter on marine radars.

    Science.gov (United States)

    Grande, Olatz; Cañizo, Josune; Angulo, Itziar; Jenn, David; Danoon, Laith R; Guerra, David; de la Vega, David

    2014-01-01

    The potential impact that offshore wind farms may cause on nearby marine radars should be considered before the wind farm is installed. Strong radar echoes from the turbines may degrade radars' detection capability in the area around the wind farm. Although conventional computational methods provide accurate results of scattering by wind turbines, they are not directly implementable in software tools that can be used to conduct the impact studies. This paper proposes a simple model to assess the clutter that wind turbines may generate on marine radars. This method can be easily implemented in the system modeling software tools for the impact analysis of a wind farm in a real scenario.

  19. Wind turbine rotor aerodynamics : The IEA MEXICO rotor explained

    NARCIS (Netherlands)

    Zhang, Y.

    2017-01-01

    Wind turbines are operating under very complex and uncontrolled environmental conditions, including atmospheric turbulence, atmospheric boundary layer effects, directional and spatial variations in wind shear, etc. Over the past decades, the size of a commercial wind turbine has increased

  20. Gaussian vs non-Gaussian turbulence: impact on wind turbine loads

    DEFF Research Database (Denmark)

    Berg, Jacob; Natarajan, Anand; Mann, Jakob

    2016-01-01

    taking into account the safety factor for extreme moments. Other extreme load moments as well as the fatigue loads are not affected because of the use of non-Gaussian turbulent inflow. It is suggested that the turbine thus acts like a low-pass filter that averages out the non-Gaussian behaviour, which......From large-eddy simulations of atmospheric turbulence, a representation of Gaussian turbulence is constructed by randomizing the phases of the individual modes of variability. Time series of Gaussian turbulence are constructed and compared with its non-Gaussian counterpart. Time series from the two...

  1. Available and announced offshore wind turbines

    International Nuclear Information System (INIS)

    Ilzhoefer, L.

    2012-01-01

    At the end of 2011, about 4000 MW of offshore wind capacity had been installed in Europe. With market shares of respectively 50% and 40%, Siemens and Vestas are the dominant manufacturers on this market. In the field of offshore wind, Siemens is primarily successful with its wind turbine type SET3,6 (3.6 MW) and Vestas with the V90 of 3.0 MW. The offshore wind turbines of other manufacturers that have a higher capacity do not play a significant role with their market share. [nl

  2. Power Electronics Converters for Wind Turbine Systems

    DEFF Research Database (Denmark)

    Blaabjerg, Frede; Liserre, Marco; Ma, Ke

    2012-01-01

    The steady growth of installed wind power together with the upscaling of the single wind turbine power capability has pushed the research and development of power converters toward full-scale power conversion, lowered cost pr kW, increased power density, and also the need for higher reliability......, in the latter case with attention to series connection and parallel connection either electrical or magnetic ones (multiphase/windings machines/transformers). It is concluded that as the power level increases in wind turbines, medium-voltage power converters will be a dominant power converter configuration...

  3. Aerodynamical noise from wind turbine generators

    International Nuclear Information System (INIS)

    Jakobsen, J.; Andersen, B.

    1993-06-01

    Two extensive measurement series of noise from wind turbines have been made during different modifications of their rotors. One series focused on the influence from the tip shape on the noise, while the other series dealt with the influence from the trailing edge. The experimental layout for the two investigations was identical. The total A-weighted noise from the wind turbine was measured in 1/3 octave bands from 50 Hz to 10 kHz in 1-minute periods simultaneously with wind speed measurements. The microphone was mounted on a hard board on the ground about 40 m directly downwind of the wind turbine, and the wind speed meter was placed at the same distance upwind of the wind turbine 10 m above ground. Regression analysis was made between noise and wind speed in each 1/3 octave band to determine the spectrum at 8 m/s. During the measurements care was taken to avoid influence from background noise, and the influence from machinery noise was minimized and corrected for. Thus the results display the aerodynamic rotor noise from the wind turbines. By use of this measurement technique, the uncertainty has been reduced to 1.5 - 2 dB per 1/3 octave band in the relevant frequency range and to about 1 dB on the total A-weighted levels. (au) (10 refs.)

  4. Sandia SWiFT Wind Turbine Manual.

    Energy Technology Data Exchange (ETDEWEB)

    White, Jonathan; LeBlanc, Bruce Philip; Berg, Jonathan Charles; Bryant, Joshua; Johnson, Wesley D.; Paquette, Joshua

    2016-01-01

    The Scaled Wind Farm Technology (SWiFT) facility, operated by Sandia National Laboratories for the U.S. Department of Energy's Wind and Water Power Program, is a wind energy research site with multiple wind turbines scaled for the experimental study of wake dynamics, advanced rotor development, turbine control, and advanced sensing for production-scale wind farms. The SWiFT site currently includes three variable-speed, pitch-regulated, three-bladed wind turbines. The six volumes of this manual provide a detailed description of the SWiFT wind turbines, including their operation and user interfaces, electrical and mechanical systems, assembly and commissioning procedures, and safety systems. Further dissemination only as authorized to U.S. Government agencies and their contractors; other requests shall be approved by the originating facility or higher DOE programmatic authority. 111 UNCLASSIFIED UNLIMITED RELEASE Sandia SWiFT Wind Turbine Manual (SAND2016-0746 ) approved by: Department Manager SWiFT Site Lead Dave Minster (6121) Date Jonathan White (6121) Date SWiFT Site Supervisor Dave Mitchell (6121) Date Note: Document revision logs are found after the title page of each volume of this manual. iv

  5. Assessment of wind turbine load measurement instrumentation

    Energy Technology Data Exchange (ETDEWEB)

    Morfiadakis, E.; Papadopoulos, K. [CRES (Greece); Borg, N. van der [ECN, Petten (Netherlands); Petersen, S.M. [Risoe, Roskilde (Denmark); Seifert, H. [DEWI, Wilhelmshaven (Germany)

    1999-03-01

    In the framework of Sub-Task3 `Wind turbine load measurement instrumentation` of EU-project `European Wind Turbine Testing Procedure Development`, the load measurement techniques have been assessed by laboratory, full scale and numerical tests. The existing methods have been reviewed with emphasis on the strain gage application techniques on composite materials and recommendations are provided for the optimisation of load measurement techniques. (au) EU. 14 refs.

  6. Wind turbine sound - metric and guidelines

    OpenAIRE

    Larsson, Conny; Öhlund, Olof

    2014-01-01

    The meteorological conditions vary over the globe but also change over the day and the year and vary a lot depending on the terrain for a certain location. The meteorological parameters govern both the wind turbine emission sound levels and the sound propagation conditions and therefore gives rise to different sound immission levels. Long-time measurements of meteorological effects on sound propagation from wind turbines over forest areas have been performed at two sites in Sweden for more th...

  7. Passively cooled direct drive wind turbine

    Science.gov (United States)

    Costin, Daniel P [Chelsea, VT

    2008-03-18

    A wind turbine is provided that passively cools an electrical generator. The wind turbine includes a plurality of fins arranged peripherally around a generator house. Each of the fins being oriented at an angle greater than zero degrees to allow parallel flow of air over the fin. The fin is further tapered to allow a constant portion of the fin to extend beyond the air stream boundary layer. Turbulence initiators on the nose cone further enhance heat transfer at the fins.

  8. On Practical tuning of Model Uncertainty in Wind Turbine Model Predictive Control

    DEFF Research Database (Denmark)

    Odgaard, Peter Fogh; Hovgaard, Tobias

    2015-01-01

    model of a wind turbine. In this paper, we investigate the impact of this approach on the performance of a wind turbine. In particular, we focus on the most non-linear operational ranges of a wind turbine. The MPC controller is designed for, tested, and evaluated at an industrial high fidelity wind......Model predictive control (MPC) has in previous works been applied on wind turbines with promising results. These results apply linear MPC, i.e., linear models linearized at different operational points depending on the wind speed. The linearized models are derived from a nonlinear first principles...... parameters in the linearized model to fit the actual physical wind turbine behavior. We evaluate the MPC with the different model parameters, and show that, e.g., over-speed events are avoided, and a good performance of the wind turbine control is obtained....

  9. Floating Foundations for Offshore Wind Turbines

    DEFF Research Database (Denmark)

    Andersen, Morten Thøtt

    The concept of harnessing the power of the wind dates all the way back to the first ships traversing the seas. Later, windmills enabled the use of wind power for industrial purposes. Since then, technology has allowed the production of clean renewable energy through the use of wind turbines......-stage physical prototype testing in wave basins without wind generating capabilities, and hence allows testing of a wider range of concepts....

  10. Structural Reliability Aspects in Design of Wind Turbines

    DEFF Research Database (Denmark)

    Sørensen, John Dalsgaard

    2007-01-01

    Reliability assessment, optimal design and optimal operation and maintenance of wind turbines are an area of significant interest for the fast growing wind turbine industry for sustainable production of energy. Offshore wind turbines in wind farms give special problems due to wake effects inside...... the farm. Reliability analysis and optimization of wind turbines require that the special conditions for wind turbine operation are taken into account. Control of the blades implies load reductions for large wind speeds and parking for high wind speeds. In this paper basic structural failure modes for wind...

  11. Wind Speed Preview Measurement and Estimation for Feedforward Control of Wind Turbines

    Science.gov (United States)

    Simley, Eric J.

    Wind turbines typically rely on feedback controllers to maximize power capture in below-rated conditions and regulate rotor speed during above-rated operation. However, measurements of the approaching wind provided by Light Detection and Ranging (lidar) can be used as part of a preview-based, or feedforward, control system in order to improve rotor speed regulation and reduce structural loads. But the effectiveness of preview-based control depends on how accurately lidar can measure the wind that will interact with the turbine. In this thesis, lidar measurement error is determined using a statistical frequency-domain wind field model including wind evolution, or the change in turbulent wind speeds between the time they are measured and when they reach the turbine. Parameters of the National Renewable Energy Laboratory (NREL) 5-MW reference turbine model are used to determine measurement error for a hub-mounted circularly-scanning lidar scenario, based on commercially-available technology, designed to estimate rotor effective uniform and shear wind speed components. By combining the wind field model, lidar model, and turbine parameters, the optimal lidar scan radius and preview distance that yield the minimum mean square measurement error, as well as the resulting minimum achievable error, are found for a variety of wind conditions. With optimized scan scenarios, it is found that relatively low measurement error can be achieved, but the attainable measurement error largely depends on the wind conditions. In addition, the impact of the induction zone, the region upstream of the turbine where the approaching wind speeds are reduced, as well as turbine yaw error on measurement quality is analyzed. In order to minimize the mean square measurement error, an optimal measurement prefilter is employed, which depends on statistics of the correlation between the preview measurements and the wind that interacts with the turbine. However, because the wind speeds encountered by

  12. Environmental impact of wind energy

    DEFF Research Database (Denmark)

    Mann, Jakob; Teilmann, Jonas

    2013-01-01

    One purpose of wind turbines is to provide pollution-free electric power at a reasonable price in an environmentally sound way. In this focus issue the latest research on the environmental impact of wind farms is presented. Offshore wind farms affect the marine fauna in both positive and negative...... emission of eight air pollutants. Finally, noise generation and its impact on humans are studied....

  13. Project WINDFARMperception Visual and acoustic impact of wind turbine farms on residents

    NARCIS (Netherlands)

    Berg, F.; Pedersen, E.; Bouma, J.; Bakker, R.

    2008-01-01

    This report gives the results of the EU financed study WINDFARMpertception on how residents perceive a wind farm in their living environment as far as sound and sight are concerned. The study includes a postal survey among Dutch residents (n = 725, response rate: 37%) and an assessment of their

  14. Behavior of bats at wind turbines.

    Science.gov (United States)

    Cryan, Paul M; Gorresen, P Marcos; Hein, Cris D; Schirmacher, Michael R; Diehl, Robert H; Huso, Manuela M; Hayman, David T S; Fricker, Paul D; Bonaccorso, Frank J; Johnson, Douglas H; Heist, Kevin; Dalton, David C

    2014-10-21

    Wind turbines are causing unprecedented numbers of bat fatalities. Many fatalities involve tree-roosting bats, but reasons for this higher susceptibility remain unknown. To better understand behaviors associated with risk, we monitored bats at three experimentally manipulated wind turbines in Indiana, United States, from July 29 to October 1, 2012, using thermal cameras and other methods. We observed bats on 993 occasions and saw many behaviors, including close approaches, flight loops and dives, hovering, and chases. Most bats altered course toward turbines during observation. Based on these new observations, we tested the hypotheses that wind speed and blade rotation speed influenced the way that bats interacted with turbines. We found that bats were detected more frequently at lower wind speeds and typically approached turbines on the leeward (downwind) side. The proportion of leeward approaches increased with wind speed when blades were prevented from turning, yet decreased when blades could turn. Bats were observed more frequently at turbines on moonlit nights. Taken together, these observations suggest that bats may orient toward turbines by sensing air currents and using vision, and that air turbulence caused by fast-moving blades creates conditions that are less attractive to bats passing in close proximity. Tree bats may respond to streams of air flowing downwind from trees at night while searching for roosts, conspecifics, and nocturnal insect prey that could accumulate in such flows. Fatalities of tree bats at turbines may be the consequence of behaviors that evolved to provide selective advantages when elicited by tall trees, but are now maladaptive when elicited by wind turbines.

  15. Dynamic Properties of Offshore Wind Turbine Foundations

    DEFF Research Database (Denmark)

    Damgaard, Mads

    frequencies. The highly variable and cyclic loads on the rotor, tower and foundation, caused by wind and wave loads as well as low-frequent excitations from the rotor blades, all demand special fatigue design considerations and create an even greater demand for a fuller appreciation of how the wind turbine...... and material damping in the soil. Modal properties in terms of natural frequencies and corresponding damping ratios of offshore wind turbines are investigated by full-scale modal testing and simple numerical quasi-static simulations. The analyses show distinctly time-varying inherent modal properties that...... of the soil indicates that the modal properties and cross-wind fatigue loads of offshore wind turbines are strongly affected by the interrelation effects between the foundation and subsoil....

  16. Damping Wind and Wave Loads on a Floating Wind Turbine

    DEFF Research Database (Denmark)

    Christiansen, Søren; Bak, Thomas; Knudsen, Torben

    2013-01-01

    Offshore wind energy capitalizes on the higher and less turbulent wind speeds at sea. To enable deployment of wind turbines in deep-water locations, structures are being explored, where wind turbines are placed on a floating platform. This combined structure presents a new control problem, due...... to the partly unconstrained movement of the platform and ocean wave excitation. If this additional complexity is not dealt with properly, this may lead to a significant increase in the structural loads and, potentially, instability of the controlled system. In this paper, the wave excitation is investigated......, and we show the influence that both wind speed, wave frequencies and misalignment between wind and waves have on the system dynamics. A new control model is derived that extends standard turbine models to include the hydrodynamics, additional platform degrees of freedom, the platform mooring system...

  17. Unsustainable Wind Turbine Blade Disposal Practices in the United States.

    Science.gov (United States)

    Ramirez-Tejeda, Katerin; Turcotte, David A; Pike, Sarah

    2017-02-01

    Finding ways to manage the waste from the expected high number of wind turbine blades in need of disposal is crucial to harvest wind energy in a truly sustainable manner. Landfilling is the most cost-effective disposal method in the United States, but it imposes significant environmental impacts. Thermal, mechanical, and chemical processes allow for some energy and/or material recovery, but they also carry potential negative externalities. This article explores the main economic and environmental issues with various wind turbine blade disposal methods. We argue for the necessity of policy intervention that encourages industry to develop better technologies to make wind turbine blade disposal sustainable, both environmentally and economically. We present some of the technological initiatives being researched, such as the use of bio-derived resins and thermoplastic composites in the manufacturing process of the blades.

  18. Load prediction of stall regulated wind turbines

    Energy Technology Data Exchange (ETDEWEB)

    Bjoerck, A.; Dahlberg, J.Aa. [Aeronautical Research Inst. of Sweden, Bromma (Sweden); Carlen, I. [Chalmers Univ. of Technology, Goeteborg (Sweden). Div. of Marine Structural Engineering; Ganander, H. [Teknikgruppen AB, Sollentua (Sweden)

    1996-12-01

    Measurements of blade loads on a turbine situated in a small wind farm shows that the highest blade loads occur during operation close to the peak power i.e. when the turbine operates in the stall region. In this study the extensive experimental data base has been utilised to compare loads in selected campaigns with corresponding load predictions. The predictions are based on time domain simulations of the wind turbine structure, performed by the aeroelastic code VIDYN. In the calculations a model were adopted in order to include the effects of dynamic stall. This paper describes the work carried out so far within the project and key results. 5 refs, 10 figs

  19. Analysis of counter-rotating wind turbines

    DEFF Research Database (Denmark)

    Shen, Wen Zhong; Zakkam, Vinod Arun Kumar; Sørensen, Jens Nørkær

    2007-01-01

    This paper presents a study on the performance of a wind turbine with two counter-rotating (CRWT) rotors. The characteristics of the two counter-rotating rotors are on a 3-bladed Nordtank 500 kW rotor. The analysis has been carried out by using an Actuator Line technique implemented in the Navier......-Stokes code EllipSys3D. The analysis shows that the Annual Energy Production can be increased to about 43.5 %, as compared to a wind turbine with a single rotor. In order to determine the optimal settings of the CRWT turbine, parameters such as distance between two rotors and rotational speed have been...

  20. Jet spoiler arrangement for wind turbine

    Science.gov (United States)

    Cyrus, Jack D.; Kadlec, Emil G.; Klimas, Paul C.

    1985-01-01

    An air jet spoiler arrangement is provided for a Darrieus-type vertical axis wind-powered turbine. Air is drawn into hollow turbine blades through air inlets at the ends thereof and is ejected in the form of air jets through small holes or openings provided along the lengths of the blades. The air jets create flow separation at the surfaces of the turbine blades, thereby inducing stall conditions and reducing the output power. A feedback control unit senses the power output of the turbine and controls the amount of air drawn into the air inlets accordingly.

  1. Impacts of the operation of wind turbines as perceived by residents in concerned areas

    Czech Academy of Sciences Publication Activity Database

    Frantál, Bohumil; Kučera, P.

    2009-01-01

    Roč. 17, č. 2 (2009), s. 34-43 ISSN 1210-8812 R&D Projects: GA AV ČR(CZ) KJB700860801 Institutional research plan: CEZ:AV0Z30860518 Keywords : wind energy * perception * social acceptance * Czech Republic Subject RIV: AO - Sociology, Demography http://www.scopus.com/record/display.url?eid=2-s2.0-70449331298&origin

  2. 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...

  3. Infrasound emission generated by wind turbines

    Science.gov (United States)

    Ceranna, Lars; Pilger, Christoph

    2014-05-01

    Aerodynamic noise emissions from the continuously growing number of wind turbines in Germany are creating increasing problems for infrasound recording systems. Such systems are equipped with highly sensitive micro pressure sensors, which are accurately measuring acoustic signals in a frequency range inaudible to humans. At infrasound station IGADE, north of Bremen, a constantly increasing background noise has been observed throughout the years since its installation in 2005. The spectral peaks are reflecting well the blade passing harmonics, which vary with prevailing wind speeds. Overall, a decrease is noted for the infrasound array's detection capability. This aspect is particularly important for the other two sites of the German infrasound stations I26DE in the Bavarian Forest and I27DE in Antarctica, because plans for installing wind turbines near these locations are being under discussion. These stations are part of the International Monitoring System (IMS) verifying compliance with the Comprehensive Nuclear-Test-Ban Treaty (CTBT), and have to meet stringent specifications with respect to infrasonic background noise. Therefore data obtained during a field experiment with mobile micro-barometer stations for measuring the infrasonic pressure level of a single horizontal-axis wind turbine have been revisited. The results of this experiment successfully validate a theoretical model which estimates the generated sound pressure level of wind turbines and makes it possible to specify the minimum allowable distance between wind turbines and infrasound stations for undisturbed recording. Since the theoretical model also takes wind turbine design parameters into account, suitable locations for planned infrasound stations outside the determined disturbance range can be found, which will be presented; and vice versa, the model calculations' results for fixing the minimum distance for wind turbines planned for installation in the vicinity of an existing infrasound array.

  4. Large superconducting wind turbine generators

    DEFF Research Database (Denmark)

    Abrahamsen, Asger Bech; Magnusson, Niklas; Jensen, Bogi Bech

    2012-01-01

    and the rotation speed is lowered in order to limit the tip speed of the blades. The ability of superconducting materials to carry high current densities with very small losses might facilitate a new class of generators operating with an air gap flux density considerably higher than conventional generators...... and thereby having a smaller size and weight [1, 2]. A 5 MW superconducting wind turbine generator forms the basics for the feasibility considerations, particularly for the YBCO and MgB2 superconductors entering the commercial market. Initial results indicate that a 5 MW generator with an active weight of 34...... tons, diameter of 4.2 m and length of 1.2 m can be realized using superconductors carrying 300 A/mm2 in a magnetic field of 4 T and an air gap flux density of the order 2.5 T. The results are compared to the performance of available superconductors, as well as the near future forecasted performance....

  5. Frequency based Wind Turbine Gearbox Fault Detection applied to a 750 kW Wind Turbine

    DEFF Research Database (Denmark)

    Odgaard, Peter Fogh; Nejad, Amir R.

    2014-01-01

    turbines. One of the critical components in modern wind turbines is the gearbox. Failures in the gearbox are costly both due to the cost of the gearbox itself, but also due to lost power generation during repair of it. Wind turbine gearboxes are consequently monitored by condition monitoring systems...... operating in parallel with the control system, and also uses additional sensors measuring different accelerations and noises, etc. In this paper gearbox data from high fidelity gearbox model of a 750 kW wind turbine gearbox, simulated with and without faults are used to shown the potential of frequency...

  6. Acoustic Tests of Small Wind Turbines: Preprint

    Energy Technology Data Exchange (ETDEWEB)

    Migliore, P.; van Dam, J.; Huskey, A.

    2003-10-01

    Eight small wind turbines ranging from 400 watts to 100 kW in rated power were tested for acoustic emissions at the U.S. Department of Energy's National Renewable Energy Laboratory. Rigorous test procedures based on international standards were followed for measurements and data analyses. Results are presented in the form of sound pressure level versus wind speed, where the sound was recorded downwind of the turbine at a distance equal to the hub height plus half the rotor diameter. When there was sufficient separation between wind turbine noise and background noise, the apparent sound power level was calculated. In several cases, this was not possible. The implications of this problem are discussed briefly. Some of the configurations tested were specifically developed to reduce the noise level of their predecessors. Test data for these machines demonstrate marked progress toward quieter turbines.

  7. Nonlinear Multibody Dynamics of Wind Turbines

    DEFF Research Database (Denmark)

    Holm-Jørgensen, Kristian

    The continuing development of wind turbines aim at higher effect production and reducing the purchase and maintenance costs for the customers. This demands that the components in the wind turbine are optimized closer to the limit than previously. In order to determine the design loads...... turbine blade with large nonlinear displacements it has shown most favorable to use the end points in the substructure for updating the moving frames. For speeding up dynamical simulations for use in e.g. active control or parameter studies, system reduction of substructures in the multibody formulation...... at the assembling point. This method is more general and can also be used to model the blade in e.g. two substructures or to model other components in the wind turbine. To determine the structural properties of a blade for use in beam element models, a FEmodel is implemented which besides the more common beam...

  8. Wind turbine remote control using Android devices

    Science.gov (United States)

    Rat, C. L.; Panoiu, M.

    2018-01-01

    This paper describes the remote control of a wind turbine system over the internet using an Android device, namely a tablet or a smartphone. The wind turbine workstation contains a LabVIEW program which monitors the entire wind turbine energy conversion system (WECS). The Android device connects to the LabVIEW application, working as a remote interface to the wind turbine. The communication between the devices needs to be secured because it takes place over the internet. Hence, the data are encrypted before being sent through the network. The scope was the design of remote control software capable of visualizing real-time wind turbine data through a secure connection. Since the WECS is fully automated and no full-time human operator exists, unattended access to the turbine workstation is needed. Therefore the device must not require any confirmation or permission from the computer operator in order to control it. Another condition is that Android application does not have any root requirements.

  9. 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...... behaviour of the turbine, loads at cut-in and braking, rotor torque at stopped condition, and noise emission....

  10. Study on wind turbine arrangement for offshore wind farms

    DEFF Research Database (Denmark)

    Shen, Wen Zhong; Mikkelsen, Robert Flemming

    2011-01-01

    In this paper, the separation distance between two neighboring offshore wind turbines has been carried out by using the Actuator Line/Navier-Stokes technique developed at the Technical University of Denmark (DTU). Under offshore atmospheric conditions, Large Eddy Simulation has been performed for...... to the turbulence mixing. This study hints that the optimal separation distance between neighboring turbines for offshore wind farms should be 7 rotor diameters....

  11. Commercialization of an Advanced Gearless Midsize Wind Turbine

    Energy Technology Data Exchange (ETDEWEB)

    McKay, Chris [Northern Power Systems, Inc., Barre, VT (United States); Ellis, Kyle [Northern Power Systems, Inc., Barre, VT (United States)

    2017-03-24

    The objective of this project was the development and eventual commercialization of a Gearless Wind Turbine of rated power 450 kW. While the product was to be based on existing technology, a significant amount of new engineering effort was expected to be required to ensure maximum efficiency and realistic placement within the market. Expected benefits included positive impact on green job creation in over 15 states as well as strengthen the U.S. domestic capacity for turbine engineering.

  12. Footprints in the wind? Environmental impacts of wind power development

    Energy Technology Data Exchange (ETDEWEB)

    Magoha, P. [Jomo Kenyatta University of Agriculture and Technology, Nairobi (Cayman Islands). Dept. of Mechanical Engineering

    2002-10-01

    This paper reviews the environmental impacts of wind power development and examines noise generated by wind turbines, noise control methods, visual impacts and visibility, and the impact on wildlife and natural habitat. Details are given of other impacts such as electromagnetic interference and the disposal of materials used in the manufacture of parts of wind energy converters. Political issues and social costs of wind energy are considered.

  13. Wind Turbine Controller to Mitigate Structural Loads on a Floating Wind Turbine Platform

    Energy Technology Data Exchange (ETDEWEB)

    Fleming, Paul A.; Peiffer, Antoine; Schlipf, David

    2016-06-24

    This paper summarizes the control design work that was performed to optimize the controller of a wind turbine on the WindFloat structure. The WindFloat is a semi-submersible floating platform designed to be a support structure for a multi-megawatt power-generating wind turbine. A controller developed for a bottom-fixed wind turbine configuration was modified for use when the turbine is mounted on the WindFloat platform. This results in an efficient platform heel resonance mitigation scheme. In addition several control modules, designed with a coupled linear model, were added to the fixed-bottom baseline controller. The approach was tested in a fully coupled nonlinear aero-hydroelastic simulation tool in which wind and wave disturbances were modeled. This testing yielded significant improvements in platform global performance and tower-base-bending loading.

  14. Underwater noise from three types of offshore wind turbines: estimation of impact zones for harbor porpoises and harbor seals.

    Science.gov (United States)

    Tougaard, Jakob; Henriksen, Oluf Damsgaard; Miller, Lee A

    2009-06-01

    Underwater noise was recorded from three different types of wind turbines in Denmark and Sweden (Middelgrunden, Vindeby, and Bockstigen-Valar) during normal operation. Wind turbine noise was only measurable above ambient noise at frequencies below 500 Hz. Total sound pressure level was in the range 109-127 dB re 1 microPa rms, measured at distances between 14 and 20 m from the foundations. The 1/3-octave noise levels were compared with audiograms of harbor seals and harbor porpoises. Maximum 1/3-octave levels were in the range 106-126 dB re 1 microPa rms. Maximum range of audibility was estimated under two extreme assumptions on transmission loss (3 and 9 dB per doubling of distance, respectively). Audibility was low for harbor porpoises extending 20-70 m from the foundation, whereas audibility for harbor seals ranged from less than 100 m to several kilometers. Behavioral reactions of porpoises to the noise appear unlikely except if they are very close to the foundations. However, behavioral reactions from seals cannot be excluded up to distances of a few hundred meters. It is unlikely that the noise reaches dangerous levels at any distance from the turbines and the noise is considered incapable of masking acoustic communication by seals and porpoises.

  15. Flow separation on wind turbines blades

    NARCIS (Netherlands)

    Corten, G.P.

    2001-01-01

    In the year 2000, 15GW of wind power was installed throughout the world, producing 100PJ of energy annually. This contributes to the total electricity demand by only 0.2%. Both the installed power and the generated energy are increasing by 30% per year world-wide. If the airflow over wind turbine

  16. Power electronics converters for wind turbine systems

    DEFF Research Database (Denmark)

    Blaabjerg, Frede; Liserre, Marco; Ma, Ke

    2011-01-01

    The steady growth of installed wind power which reached 200 GW capacity in 2010, together with the up-scaling of the single wind turbine power capability - 7 MW’s has been announced by manufacturers - has pushed the research and development of power converters towards full scale power conversion,...

  17. Tjæreborg Wind Turbine

    DEFF Research Database (Denmark)

    Øye, Stig

    1991-01-01

    This paper presents results from the fourth measurement camapign at the Tjæreborg (Tjaereborg) WInd Turbine during operation with stepwise pitch angle changes. The measurements cover one hour of operation at wind speeds between 7 and 10 m/s aceraging approximately 8.7 m/s....

  18. Wind turbine wake measurement in complex terrain

    DEFF Research Database (Denmark)

    Hansen, Kurt Schaldemose; Larsen, Gunner Chr.; Menke, Robert

    2016-01-01

    SCADA data from a wind farm and high frequency time series measurements obtained with remote scanning systems have been analysed with focus on identification of wind turbine wake properties in complex terrain. The analysis indicates that within the flow regime characterized by medium to large...

  19. Multilevel converters for 10 MW Wind Turbines

    DEFF Research Database (Denmark)

    Ma, Ke; Blaabjerg, Frede

    2011-01-01

    Several promising multi-level converter configurations for 10 MW Wind Turbines both with direct drive and one-stage gear box drive using Permanent Magnet Synchronous Generator (PMSG) are proposed, designed and compared. Reliability is a crucial indicator for large scale wind power converters...

  20. Fatigue Reliability of Offshore Wind Turbine Systems

    DEFF Research Database (Denmark)

    Marquez-Dominguez, Sergio; Sørensen, John Dalsgaard

    2012-01-01

    Optimization of the design of offshore wind turbine substructures with respect to fatigue loads is an important issue in offshore wind energy. A stochastic model is developed for assessing the fatigue failure reliability. This model can be used for direct probabilistic design and for calibration...... of appropriate partial safety factors / fatigue design factors (FDF) for steel substructures of offshore wind turbines (OWTs). The fatigue life is modeled by the SN approach. Design and limit state equations are established based on the accumulated fatigue damage. The acceptable reliability level for optimal...... fatigue design of OWTs is discussed and results for reliability assessment of typical fatigue critical design of offshore steel support structures are presented....

  1. Predicting Faults in Wind Turbines Using SCADA Data

    DEFF Research Database (Denmark)

    Borchersen, Anders Bech; Larsen, Jesper Abildgaard; Stoustrup, Jakob

    2013-01-01

    The cost of operation and maintenance of wind turbines is a significant part of the overall cost of wind turbines. To reduce this cost a method for enabling early fault detection is proposed and tested in this paper. The method is taking advantage of the fact that wind turbines in wind farms are ...

  2. Load attenuating passively adaptive wind turbine blade

    Science.gov (United States)

    Veers, Paul S.; Lobitz, Donald W.

    2003-01-07

    A method and apparatus for improving wind turbine performance by alleviating loads and controlling the rotor. The invention employs the use of a passively adaptive blade that senses the wind velocity or rotational speed, and accordingly modifies its aerodynamic configuration. The invention exploits the load mitigation prospects of a blade that twists toward feather as it bends. The invention includes passively adaptive wind turbine rotors or blades with currently preferred power control features. The apparatus is a composite fiber horizontal axis wind-turbine blade, in which a substantial majority of fibers in the blade skin are inclined at angles of between 15 and 30 degrees to the axis of the blade, to produces passive adaptive aeroelastic tailoring (bend-twist coupling) to alleviate loading without unduly jeopardizing performance.

  3. Advantages on monitoring wind turbine nacelle oscillation

    DEFF Research Database (Denmark)

    Skrimpas, Georgios Alexandros; Marhadi, Kun Saptohartyadi; Hilmisson, Reynir

    2015-01-01

    and vibrations on blades, tower and drive train components, which may jeopardize their working condition. The present paper deals with the comparison and analysis of vibration signals from wind turbines subjected to various failure modes and operating conditions, such as blade misalignment, pitch malfunction......, ice accretion, damaged blade tips and yaw system defects. Theoretical analysis of nacelle movement at down wind and lateral direction is presented along with field results from multi megawatt wind turbines. Additionally the paper discusses the employment of nacelle accelerometers for cross reference......Nacelle oscillation monitoring, where accelerometers are mounted on the nacelle frame, is integral part of modern condition monitoring systems towards holistic and consistent health assessment of wind turbines. It enables detection of abnormal behavior associated to increased stresses...

  4. Wind Turbine Micropitting Workshop: A Recap

    Energy Technology Data Exchange (ETDEWEB)

    Sheng, S.

    2010-02-01

    Micropitting is a Hertzian fatigue phenomenon that affects many wind turbine gearboxes, and it affects the reliability of the machines. With the major growth and increasing dependency on renewable energy, mechanical reliability is an extremely important issue. The U.S. Department of Energy has made a commitment to improving wind turbine reliability and the National Renewable Energy Laboratory (NREL) has started a gearbox reliability project. Micropitting as an issue that needed attention came to light through this effort. To understand the background of work that had already been accomplished, and to consolidate some level of collective understanding of the issue by acknowledged experts, NREL hosted a wind turbine micropitting workshop, which was held at the National Wind Technology Center in Boulder, Colorado, on April 15 and 16, 2009.

  5. Health effects and wind turbines: A review of the literature

    Directory of Open Access Journals (Sweden)

    Ollson Christopher A

    2011-09-01

    Full Text Available Abstract Background Wind power has been harnessed as a source of power around the world. Debate is ongoing with respect to the relationship between reported health effects and wind turbines, specifically in terms of audible and inaudible noise. As a result, minimum setback distances have been established world-wide to reduce or avoid potential complaints from, or potential effects to, people living in proximity to wind turbines. People interested in this debate turn to two sources of information to make informed decisions: scientific peer-reviewed studies published in scientific journals and the popular literature and internet. Methods The purpose of this paper is to review the peer-reviewed scientific literature, government agency reports, and the most prominent information found in the popular literature. Combinations of key words were entered into the Thomson Reuters Web of KnowledgeSM and the internet search engine Google. The review was conducted in the spirit of the evaluation process outlined in the Cochrane Handbook for Systematic Reviews of Interventions. Results Conclusions of the peer reviewed literature differ in some ways from those in the popular literature. In peer reviewed studies, wind turbine annoyance has been statistically associated with wind turbine noise, but found to be more strongly related to visual impact, attitude to wind turbines and sensitivity to noise. To date, no peer reviewed articles demonstrate a direct causal link between people living in proximity to modern wind turbines, the noise they emit and resulting physiological health effects. If anything, reported health effects are likely attributed to a number of environmental stressors that result in an annoyed/stressed state in a segment of the population. In the popular literature, self-reported health outcomes are related to distance from turbines and the claim is made that infrasound is the causative factor for the reported effects, even though sound pressure

  6. Health effects and wind turbines: a review of the literature.

    Science.gov (United States)

    Knopper, Loren D; Ollson, Christopher A

    2011-09-14

    Wind power has been harnessed as a source of power around the world. Debate is ongoing with respect to the relationship between reported health effects and wind turbines, specifically in terms of audible and inaudible noise. As a result, minimum setback distances have been established world-wide to reduce or avoid potential complaints from, or potential effects to, people living in proximity to wind turbines. People interested in this debate turn to two sources of information to make informed decisions: scientific peer-reviewed studies published in scientific journals and the popular literature and internet. The purpose of this paper is to review the peer-reviewed scientific literature, government agency reports, and the most prominent information found in the popular literature. Combinations of key words were entered into the Thomson Reuters Web of KnowledgeSM and the internet search engine Google. The review was conducted in the spirit of the evaluation process outlined in the Cochrane Handbook for Systematic Reviews of Interventions. Conclusions of the peer reviewed literature differ in some ways from those in the popular literature. In peer reviewed studies, wind turbine annoyance has been statistically associated with wind turbine noise, but found to be more strongly related to visual impact, attitude to wind turbines and sensitivity to noise. To date, no peer reviewed articles demonstrate a direct causal link between people living in proximity to modern wind turbines, the noise they emit and resulting physiological health effects. If anything, reported health effects are likely attributed to a number of environmental stressors that result in an annoyed/stressed state in a segment of the population. In the popular literature, self-reported health outcomes are related to distance from turbines and the claim is made that infrasound is the causative factor for the reported effects, even though sound pressure levels are not measured. What both types of studies

  7. Equivalent models of wind farms by using aggregated wind turbines and equivalent winds

    International Nuclear Information System (INIS)

    Fernandez, L.M.; Garcia, C.A.; Saenz, J.R.; Jurado, F.

    2009-01-01

    As a result of the increasing wind farms penetration on power systems, the wind farms begin to influence power system, and therefore the modeling of wind farms has become an interesting research topic. In this paper, new equivalent models of wind farms equipped with wind turbines based on squirrel-cage induction generators and doubly-fed induction generators are proposed to represent the collective behavior on large power systems simulations, instead of using a complete model of wind farms where all the wind turbines are modeled. The models proposed here are based on aggregating wind turbines into an equivalent wind turbine which receives an equivalent wind of the ones incident on the aggregated wind turbines. The equivalent wind turbine presents re-scaled power capacity and the same complete model as the individual wind turbines, which supposes the main feature of the present equivalent models. Two equivalent winds are evaluated in this work: (1) the average wind from the ones incident on the aggregated wind turbines with similar winds, and (2) an equivalent incoming wind derived from the power curve and the wind incident on each wind turbine. The effectiveness of the equivalent models to represent the collective response of the wind farm at the point of common coupling to grid is demonstrated by comparison with the wind farm response obtained from the detailed model during power system dynamic simulations, such as wind fluctuations and a grid disturbance. The present models can be used for grid integration studies of large power system with an important reduction of the model order and the computation time

  8. The design of wind turbine for electrical power generation in Malaysian wind characteristics

    International Nuclear Information System (INIS)

    Abas Ab Wahab; Chong Wen Thong

    2000-01-01

    The paper describes the study of a wind turbine for electrical power generation in Malaysia wind characteristics. In this research, the wind turbine is designs based on the local wind characteristics and tries to avoid the problems faced in the past (turbine design, access, manpower and technical). The new wind turbine rotor design for a medium speed wind speed turbine utilises the concept of open-close type of horizontal axis (up-wind) wind turbine is intended to widen the optimum performance range for electrical generation in Malaysia wind characteristics. The wind turbine has been designed to cut-in at a lower speed, and to provide the rotation speed that high enough to run a generator. The analysis and design of new low speed wind turbine blades and open-close turbine rotor and prediction of turbine performance are being detailed in this paper. (Author)

  9. Lightning protection for wind turbines in Vietnam

    Directory of Open Access Journals (Sweden)

    Thuan Nguyen

    2017-01-01

    Full Text Available Wind energy has become increasingly important in the total electrical energy supply mix in Vietnam over the last few years. Small, kW turbines were installed in isolated areas a decade ago, while wind farms of several MW to few hundred MW are now being connected directly to national grid, with many additional projects in planning or under construction to fulfill an objective of 6% of the total installed capacity by 2030 (approximately 6200 MW of wind energy component. The increase in wind farm generation results in increased damage from lightning. In this paper, the annual frequency of lightning strikes to wind turbines in Vietnam is calculated using electrogeometric model. Reported lightning incidents to three major wind farms in Vietnam are summarized. Possible causes of failure are discussed, and an EMTP simulation for each incident was performed accordingly. The simulations suggest the failure mechanisms as well the potential of improved grounding to reduce lightning induced damage in future windfarms.

  10. Modern Control Design for Flexible Wind Turbines

    Energy Technology Data Exchange (ETDEWEB)

    Wright, A. D.

    2004-07-01

    Control can improve energy capture and reduce dynamic loads in wind turbines. In the 1970s and 1980s, wind turbines used classical control designs to regulate power and speed. The methods used, however, were not always successful. Modern turbines are larger, mounted on taller towers, and more dynamically active than their predecessors. Control systems to regulate turbine power and maintain stable, closed-loop behavior in the presence of turbulent wind inflow will be critical for these designs. This report applies modern state-space control design methods to a two-bladed teetering hub upwind machine at the National Wind Technology Center (NWTC), which is managed by the U.S. Department of Energy's National Renewable Energy Laboratory (NREL) in Golden, Colorado. The design objective is to regulate turbine speed and enhance damping in several low-damped flexible modes of the turbine. Starting with simple control algorithms based on linear models, complexity is added incrementally until the desired performance is firmly established.

  11. Detection of Wind Evolution and Lidar Trajectory Optimization for Lidar-Assisted Wind Turbine Control

    Directory of Open Access Journals (Sweden)

    David Schlipf

    2015-11-01

    Full Text Available Recent developments in remote sensing are offering a promising opportunity to rethink conventional control strategies of wind turbines. With technologies such as lidar, the information about the incoming wind field - the main disturbance to the system - can be made available ahead of time. Initial field testing of collective pitch feedforward control shows, that lidar measurements are only beneficial if they are filtered properly to avoid harmful control action. However, commercial lidar systems developed for site assessment are usually unable to provide a usable signal for real time control. Recent research shows, that the correlation between the measurement of rotor effective wind speed and the turbine reaction can be modeled and that the model can be used to optimize a scan pattern. This correlation depends on several criteria such as turbine size, position of the measurements, measurement volume, and how the wind evolves on its way towards the rotor. In this work the longitudinal wind evolution is identified with the line-of-sight measurements of a pulsed lidar system installed on a large commercial wind turbine. This is done by staring directly into the inflowing wind during operation of the turbine and fitting the coherence between the wind at different measurement distances to an exponential model taking into account the yaw misalignment, limitation to line-of-sight measurements and the pulse volume. The identified wind evolution is then used to optimize the scan trajectory of a scanning lidar for lidar-assisted feedforward control in order to get the best correlation possible within the constraints of the system. Further, an adaptive filer is fitted to the modeled correlation to avoid negative impact of feedforward control because of uncorrelated frequencies of the wind measurement. The main results of the presented work are a first estimate of the wind evolution in front of operating wind turbines and an approach which manufacturers of

  12. Industrial wind turbines and adverse health effects.

    Science.gov (United States)

    Jeffery, Roy D; Krogh, Carmen M E; Horner, Brett

    2014-01-01

    Some people living in the environs of industrial wind turbines (IWTs) report experiencing adverse health and socioeconomic effects. This review considers the hypothesis that annoyance from audible IWTs is the cause of these adverse health effects. We searched PubMed and Google Scholar for articles published since 2000 that included the terms "wind turbine health," "wind turbine infrasound," "wind turbine annoyance," "noise annoyance" or "low frequency noise" in the title or abstract. Industrial wind turbines produce sound that is perceived to be more annoying than other sources of sound. Reported effects from exposure to IWTs are consistent with well-known stress effects from persistent unwanted sound. If placed too close to residents, IWTs can negatively affect the physical, mental and social well-being of people. There is sufficient evidence to support the conclusion that noise from audible IWTs is a potential cause of health effects. Inaudible low-frequency noise and infrasound from IWTs cannot be ruled out as plausible causes of health effects.

  13. Assessment and prediction of wind turbine noise

    International Nuclear Information System (INIS)

    Lowson, M.V.

    1993-01-01

    The significance of basic aerodynamic noise sources for wind turbine noise are assessed, using information on the aero-acoustic mechanisms of other rotors, which have been studied in depth for many years. From the analysis, areas of potential improvement in wind turbine noise prediction are defined. Suggestions are made for approaches to wind turbine noise control which separate the noise problems at cut-in from those at rated power. Some of these offer the possibility of noise reduction without unfavourable effects on performance. Based on this analysis, a new model for prediction of wind turbine noise is presented and comparisons made between prediction and experiment. The model is based on well established aeroacoustic theory and published laboratory data for the two principal sources, inflow turbulence and boundary layer trailing edge interaction. The new method gives good agreement with experiment with the case studied so far. Parametric trends and sensitivities for the model are presented. Comparisons with previous prediction methods are also given. A consequence of the new model is to put more emphasis on boundary layer trailing edge interaction as a noise source. There are prospects for reducing noise from this source detail changes to the wind turbine design. (author)

  14. A neuro-fuzzy controlling algorithm for wind turbine

    Energy Technology Data Exchange (ETDEWEB)

    Li Lin [Tampere Univ. of Technology (Finland); Eriksson, J.T. [Tampere Univ. of Technology (Finland)

    1995-12-31

    The wind turbine control system is stochastic and nonlinear, offering a demanding field for different control methods. An improved and efficient controller will have great impact on the cost-effectiveness of the technology. In this article, a design method for a self-organizing fuzzy controller is discussed, which combines two popular computational intelligence techniques, neural networks and fuzzy logic. Based on acquisited dynamic parameters of the wind, it can effectively predict wind changes in speed and direction. Maximum power can always be extracted from the kinetic energy of the wind. Based on the stimulating experiments applying nonlinear dynamics to a `Variable Speed Fixed Angle` wind turbine, it is demonstrated that the proposed control model 3rd learning algorithm provide a predictable, stable and accurate performance. The robustness of the controller to system parameter variations and measurement disturbances is also discussed. (author)

  15. Dependence of optimal wind turbine spacing on wind farm length

    NARCIS (Netherlands)

    Stevens, Richard Johannes Antonius Maria

    2016-01-01

    Recent large eddy simulations have led to improved parameterizations of the effective roughness height of wind farms. This effective roughness height can be used to predict the wind velocity at hub-height as function of the geometric mean of the spanwise and streamwise turbine spacings and the

  16. 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...

  17. Operation Design of Wind Turbines in Strong Wind Conditions

    DEFF Research Database (Denmark)

    Shen, Wen Zhong; Montes, Melissa Barroso; Odgaard, Peter Fogh

    2012-01-01

    optimally. In order to reduce the possible increased loading, fatigue due to the wind gusts, control strategies have been considered for both constant sped and variable speed pitch regulated wind turbines. The control study shows that the designed controllers can reduce the standard deviations efficiently...

  18. Adaptive neuro-fuzzy methodology for noise assessment of wind turbine.

    Science.gov (United States)

    Shamshirband, Shahaboddin; Petković, Dalibor; Hashim, Roslan; Motamedi, Shervin

    2014-01-01

    Wind turbine noise is one of the major obstacles for the widespread use of wind energy. Noise tone can greatly increase the annoyance factor and the negative impact on human health. Noise annoyance caused by wind turbines has become an emerging problem in recent years, due to the rapid increase in number of wind turbines, triggered by sustainable energy goals set forward at the national and international level. Up to now, not all aspects of the generation, propagation and perception of wind turbine noise are well understood. For a modern large wind turbine, aerodynamic noise from the blades is generally considered to be the dominant noise source, provided that mechanical noise is adequately eliminated. The sources of aerodynamic noise can be divided into tonal noise, inflow turbulence noise, and airfoil self-noise. Many analytical and experimental acoustical studies performed the wind turbines. Since the wind turbine noise level analyzing by numerical methods or computational fluid dynamics (CFD) could be very challenging and time consuming, soft computing techniques are preferred. To estimate noise level of wind turbine, this paper constructed a process which simulates the wind turbine noise levels in regard to wind speed and sound frequency with adaptive neuro-fuzzy inference system (ANFIS). This intelligent estimator is implemented using Matlab/Simulink and the performances are investigated. The simulation results presented in this paper show the effectiveness of the developed method.

  19. Adaptive neuro-fuzzy methodology for noise assessment of wind turbine.

    Directory of Open Access Journals (Sweden)

    Shahaboddin Shamshirband

    Full Text Available Wind turbine noise is one of the major obstacles for the widespread use of wind energy. Noise tone can greatly increase the annoyance factor and the negative impact on human health. Noise annoyance caused by wind turbines has become an emerging problem in recent years, due to the rapid increase in number of wind turbines, triggered by sustainable energy goals set forward at the national and international level. Up to now, not all aspects of the generation, propagation and perception of wind turbine noise are well understood. For a modern large wind turbine, aerodynamic noise from the blades is generally considered to be the dominant noise source, provided that mechanical noise is adequately eliminated. The sources of aerodynamic noise can be divided into tonal noise, inflow turbulence noise, and airfoil self-noise. Many analytical and experimental acoustical studies performed the wind turbines. Since the wind turbine noise level analyzing by numerical methods or computational fluid dynamics (CFD could be very challenging and time consuming, soft computing techniques are preferred. To estimate noise level of wind turbine, this paper constructed a process which simulates the wind turbine noise levels in regard to wind speed and sound frequency with adaptive neuro-fuzzy inference system (ANFIS. This intelligent estimator is implemented using Matlab/Simulink and the performances are investigated. The simulation results presented in this paper show the effectiveness of the developed method.

  20. Adaptive Neuro-Fuzzy Methodology for Noise Assessment of Wind Turbine

    Science.gov (United States)

    Shamshirband, Shahaboddin; Petković, Dalibor; Hashim, Roslan; Motamedi, Shervin

    2014-01-01

    Wind turbine noise is one of the major obstacles for the widespread use of wind energy. Noise tone can greatly increase the annoyance factor and the negative impact on human health. Noise annoyance caused by wind turbines has become an emerging problem in recent years, due to the rapid increase in number of wind turbines, triggered by sustainable energy goals set forward at the national and international level. Up to now, not all aspects of the generation, propagation and perception of wind turbine noise are well understood. For a modern large wind turbine, aerodynamic noise from the blades is generally considered to be the dominant noise source, provided that mechanical noise is adequately eliminated. The sources of aerodynamic noise can be divided into tonal noise, inflow turbulence noise, and airfoil self-noise. Many analytical and experimental acoustical studies performed the wind turbines. Since the wind turbine noise level analyzing by numerical methods or computational fluid dynamics (CFD) could be very challenging and time consuming, soft computing techniques are preferred. To estimate noise level of wind turbine, this paper constructed a process which simulates the wind turbine noise levels in regard to wind speed and sound frequency with adaptive neuro-fuzzy inference system (ANFIS). This intelligent estimator is implemented using Matlab/Simulink and the performances are investigated. The simulation results presented in this paper show the effectiveness of the developed method. PMID:25075621

  1. Potential Coir Fibre Composite for Small Wind Turbine Blade Application

    Directory of Open Access Journals (Sweden)

    Bakri Bakri

    2017-03-01

    Full Text Available Natural fibers have been developed as reinforcement of composite to shift synthetic fibers. One of potential natural fibers developed is coir fiber. This paper aims to describe potential coir fiber as reinforcement of composite for small wind turbine blade application. The research shows that mechanical properties ( tensile, impact, shear, flexural and compression strengths of coir fiber composite have really similar to wood properties for small wind turbine blade material, but inferior to glass fiber composite properties. The effect of weathering was also evaluated to coir fiber composite in this paper.

  2. Study on visual detection method for wind turbine blade failure

    Science.gov (United States)

    Chen, Jianping; Shen, Zhenteng

    2018-02-01

    Start your abstract here…At present, the non-destructive testing methods of the wind turbine blades has fiber bragg grating, sound emission and vibration detection, but there are all kinds of defects, and the engineering application is difficult. In this regard, three-point slope deviation method, which is a kind of visual inspection method, is proposed for monitoring the running status of wind turbine blade based on the image processing technology. A better blade image can be got through calibration, image splicing, pretreatment and threshold segmentation algorithm. Design of the early warning system to monitor wind turbine blade running condition, recognition rate, stability and impact factors of the method were statistically analysed. The experimental results shown showed that it has highly accurate and good monitoring effect.

  3. Modal Characteristics of Novel Wind Turbine Rotors with Hinged Structures

    Science.gov (United States)

    Lu, Hongya; Zeng, Pan; Lei, Liping

    2018-03-01

    The vibration problems of the wind turbine rotors have drawn public attention as the size of wind turbine has increased incredibly. Although various factors may cause the vibration problems, the flexibility is a big threat among them. Therefore, ensuring the high stiffness of the rotors by adopting novel techniques becomes a necessity. The study was a further investigation of several novel designs regarding the dynamic behaviour and the influencing mechanism. The modal testing experiments were conducted on a traditional blade and an isolated blade with the hinged rods mounted close to the root. The results showed that the rod increased both the modal frequency and the damping of the blade. More studies were done on the rods’ impact on the wind turbine rotor with a numerical model, where dimensionless parameters were defined to describe the configuration of the interveined and the bisymmetrical rods. Their influences on the modal frequencies of the rotor were analyzed and discussed.

  4. On Small-Signal Stability of Wind Power System with Full-Load Converter Interfaced Wind Turbines

    DEFF Research Database (Denmark)

    Knüppel, Thyge; Akhmatov, Vladislav; Nielsen, Jørgen Nygård

    2010-01-01

    Small-signal stability analysis of power system oscillations is a well established field within power system analysis, but not much attention has yet been paid to systems with a high penetration of wind turbines and with large wind power plants. In this paper an analysis is presented which assess...... the impact of full-load converter interfaced wind turbines on power system small-signal stability. The study is based on a 7 generator network with lightly damped inter-area modes. A detailed wind turbine model with all grid relevant control functions is used in the study. Furthermore is the wind power plant...

  5. Advances in wind turbine blade design and materials

    DEFF Research Database (Denmark)

    Wind energy is gaining critical ground in the area of renewable energy, with wind energy being predicted to provide up to 8% of the world’s consumption of electricity by 2021. Advances in wind turbine blade design and materials reviews the design and functionality of wind turbine rotor blades...... of wind turbine blades. The final part of the book describes advances in wind turbine blade materials, development and testing, including biobased composites, surface protection and coatings, structural performance testing and the design, manufacture and testing of small wind turbine blades. Advances...... in wind turbine blade design and materials offers a comprehensive review of the recent advances and challenges encountered in wind turbine blade materials and design, and will provide an invaluable reference for researchers and innovators in the field of wind energy production, including materials...

  6. Wind tunnel tests of a free yawing downwind wind turbine

    Science.gov (United States)

    Verelst, D. R. S.; Larsen, T. J.; van Wingerden, J. W.

    2014-12-01

    This research paper presents preliminary results on a behavioural study of a free yawing downwind wind turbine. A series of wind tunnel tests was performed at the TU Delft Open Jet Facility with a three bladed downwind wind turbine and a rotor radius of 0.8 meters. The setup includes an off the shelf three bladed hub, nacelle and generator on which relatively flexible blades are mounted. The tower support structure has free yawing capabilities provided at the base. A short overview on the technical details of the experiment is given as well as a brief summary of the design process. The discussed test cases show that the turbine is stable while operating in free yawing conditions. Further, the effect of the tower shadow passage on the blade flapwise strain measurement is evaluated. Finally, data from the experiment is compared with preliminary simulations using DTU Wind Energy's aeroelastic simulation program HAWC2.

  7. Clemson University Wind Turbine Drivetrain Test Facility

    Energy Technology Data Exchange (ETDEWEB)

    Tuten, James Maner [Clemson Univ., SC (United States); Haque, Imtiaz [Clemson Univ., SC (United States); Rigas, Nikolaos [Clemson Univ., SC (United States)

    2016-03-30

    In November of 2009, Clemson University was awarded a competitive grant from the U.S. Department of Energy to design, build and operate a facility for full-scale, highly accelerated mechanical testing of next-generation wind turbine drivetrain technologies. The primary goal of the project was to design, construct, commission, and operate a state-of-the-art sustainable facility that permits full-scale highly accelerated testing of advanced drivetrain systems for large wind turbines. The secondary goal was to meet the objectives of the American Recovery and Reinvestment Act of 2009, especially in job creation, and provide a positive impact on economically distressed areas in the United States, and preservation and economic recovery in an expeditious manner. The project was executed according to a managed cooperative agreement with the Department of Energy and was an extraordinary success. The resultant new facility is located in North Charleston, SC, providing easy transportation access by rail, road or ship and operates on an open access model such that it is available to the U.S. Wind Industry for research, analysis, and evaluation activities. The 72 m by 97 m facility features two mechanical dynamometer test bays for evaluating the torque and blade dynamic forces experienced by the rotors of wind turbine drivetrains. The dynamometers are rated at 7.5 MW and 15 MW of low speed shaft power and are configured as independent test areas capable of simultaneous operation. All six degrees of freedom, three linear and three rotational, for blade and rotor dynamics are replicated through the combination of a drive motor, speed reduction gearbox and a controllable hydraulic load application unit (LAU). This new LAU setup readily supports accelerated lifetime mechanical testing and load analysis for the entire drivetrain system of the nacelle and easily simulates a wide variety of realistic operating scenarios in a controlled laboratory environment. The development of these

  8. Diffuser augmented wind turbine analysis code

    Science.gov (United States)

    Carroll, Jonathan

    Wind Energy is becoming a significant source of energy throughout the world. This ever increasing field will potentially reach the limit of availability and practicality with the wind farm sites and size of the turbine itself. Therefore, it is necessary to develop innovative wind capturing devices that can produce energy in the locations where large conventional horizontal axis wind turbines (HAWTs) are too impractical to install and operate. A diffuser augmented wind turbine (DAWT) is one such innovation. DAWTs increase the power output of the rotor by increasing the wind speed into the rotor using a duct. Currently, developing these turbines is an involved process using time consuming Computational Fluid Dynamics codes. A simple and quick design tool is necessary for designers to develop efficient energy capturing devices. This work lays out the theory for a quick analysis tool for DAWTs using an axisymmetric surface vorticity method. This method allows for quick analysis of duct, hubs and rotors giving designers a general idea of the power output of the proposed hub, blade and duct geometry. The method would be similar to the way blade element momentum theory is used to design conventional HAWTs. It is determined that the presented method is viable for preliminary design of DAWTs.

  9. Who should own the nearshore wind turbines?

    DEFF Research Database (Denmark)

    Jensen, Louise Krog; Sperling, Karl

    This report examines the possibility for non-profit organisations to participate in tenders for nearshore wind turbines in Denmark under the current frame-work conditions in the area. The point of departure is a case study of the non-profit organisation Wind People’s attempt to participate with a...... their academic professional network to pull the strings and get in touch with relevant persons and actors when organising a tender or a project....... with a popular project in the Danish tender for 350 MW nearshore wind turbines. A series of in-depth interviews have been carried out with Wind People’s staff in order to make an in-depth analysis of their actions and experiences of entering into the market for nearshore wind turbines. The report concludes...... that it is not possible for non-profit organisations to participate with popular projects in connection with tenders for nearshore wind turbines in Denmark under the current framework conditions. Therefore, it is necessary to make a modification of the framework conditions. In itself, this is not sufficient to pave...

  10. Wind power production: from the characterisation of the wind resource to wind turbine technologies

    International Nuclear Information System (INIS)

    Beslin, Guy; Multon, Bernard

    2016-01-01

    Illustrated by graphs and tables, this article first describes the various factors and means related to the assessment of wind resource in the World, in Europe, and the factors which characterize a local wind resource. In this last respect, the authors indicate how local topography is taken into account to calculate wind speed, how time variations are taken into account (at the yearly, seasonal or daily level), the different methods used to model a local wind resource, how to assess the power recoverable by a wind turbine with horizontal axis (notion of Betz limit). In the second part, the authors present the different wind turbines, their benefits and drawbacks: vertical axis, horizontal axis (examples of a Danish-type wind turbine, of wind turbines designed for extreme conditions). Then, they address the technology of big wind turbines: evolution of technology and of commercial offer, aerodynamic characteristics of wind turbine and benefit of a varying speed (technological solutions, importance of the electric generator). They describe how to choose a wind turbine, how product lines are organised, how the power curve and energy capacity are determined. The issue of integration of wind energy into the power system is then addressed. The next part addressed the economy of wind energy production (annualized production cost, order of magnitude of wind electric power production cost). Future trends are discussed and offshore wind energy production is briefly addressed

  11. 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

    is not reasonable regarding the focus of the study. Therefore the power system operators should be aware of the modelling aspects of the wind power considering the related stability study and implement the required model in the appropriate power system toolbox. In this paper, the modelling aspects of wind turbines...... 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.......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...

  12. Extrapolating Satellite Winds to Turbine Operating Heights

    DEFF Research Database (Denmark)

    Badger, Merete; Pena Diaz, Alfredo; Hahmann, Andrea N.

    2016-01-01

    Ocean wind retrievals from satellite sensors are typically performed for the standard level of 10 m. This restricts their full exploitation for wind energy planning, which requires wind information at much higher levels where wind turbines operate. A new method is presented for the vertical...... extrapolation of satellitebased wind maps. Winds near the sea surface are obtained from satellite data and used together with an adaptation of the Monin–Obukhov similarity theory to estimate the wind speed at higher levels. The thermal stratification of the atmosphere is taken into account through a long...... effects and also, to some extent, for the limited number of satellite samples. The satellite-based and NWP-simulated wind profiles are almost equally accurate with respect to those from the mast. However, the satellite-based maps have a higher spatial resolution, which is particularly important...

  13. The Darrieus wind turbine for electrical power generation

    Science.gov (United States)

    Robinson, M. L.

    1981-06-01

    Aspects of wind as an energy source and the momentum theory of wind turbines are briefly examined. Types of Darrieus wind turbine are described; attention is given to a turbine with airfoil blades curved in troposkein form, and a turbine with straight blades of fixed or variable pitch. The Darrieus vertical-axis wind turbine is then considered with regard to aerodynamics, annual energy output, structures, control systems, and energy storage. Brief reviews of selected Darrieus wind turbine projects are given, including those at Magdalen Islands, Canada, Sandia Laboratories, Reading University, and Australia and New Zealand.

  14. Wind turbine blade waste in 2050.

    Science.gov (United States)

    Liu, Pu; Barlow, Claire Y

    2017-04-01

    Wind energy has developed rapidly over the last two decades to become one of the most promising and economically viable sources of renewable energy. Although wind energy is claimed to provide clean renewable energy without any emissions during operation, but it is only one side of the coin. The blades, one of the most important components in the wind turbines, made with composite, are currently regarded as unrecyclable. With the first wave of early commercial wind turbine installations now approaching their end of life, the problem of blade disposal is just beginning to emerge as a significant factor for the future. This paper is aimed at discovering the magnitude of the wind turbine blade waste problem, looking not only at disposal but at all stages of a blade's lifecycle. The first stage of the research, the subject of this paper, is to accurately estimate present and future wind turbine blade waste inventory using the most recent and most accurate data available. The result will provide a solid reference point to help the industry and policy makers to understand the size of potential environmental problem and to help to manage it better. This study starts by estimating the annual blade material usage with wind energy installed capacity and average blade weight. The effect of other waste contributing factors in the full lifecycle of wind turbine blades is then included, using industrial data from the manufacturing, testing and in-service stages. The research indicates that there will be 43 million tonnes of blade waste worldwide by 2050 with China possessing 40% of the waste, Europe 25%, the United States 16% and the rest of the world 19%. Crown Copyright © 2017. Published by Elsevier Ltd. All rights reserved.

  15. Shoosing the appropriate size wind turbine

    Energy Technology Data Exchange (ETDEWEB)

    Lynette, R. [FloWind Corp., San Rafael, CA (United States)

    1996-12-31

    Within the past several years, wind turbines rated at 400 kW and higher have been introduced into the market, and some manufacturers are developing machines rated at 750 - 1,000+ kW. This raises the question: What is the appropriate size for utility-grade wind turbines today? The answer depends upon the site where the machines will be used and the local conditions. The issues discussed in the paper are: (1) Site-Related (a) Visual, noise, erosion, television interference, interference with aviation (b) Siting efficiency (2) Logistics (a) Adequacy of roads and bridges to accept large vehicles (b) Availability and cost of cranes for erection and maintenance (c) Capability of local repair/overhauls (3) Cost Effectiveness (a) Capital costs (1) Wind Turbine (2) Infrastructure costs (b) Maintenance costs (4) Technical/Financial Risk. 1 fig., 1 tab.

  16. Shape Optimization of Wind Turbine Blades

    DEFF Research Database (Denmark)

    Wang, Xudong; Shen, Wen Zhong; Zhu, Wei Jun

    2009-01-01

    of the rotor. The design variables used in the current study are the blade shape parameters, including chord, twist and relative thickness. To validate the implementation of the aerodynamic/aero-elastic model, the computed aerodynamic results are compared to experimental data for the experimental rotor used......This paper presents a design tool for optimizing wind turbine blades. The design model is based on an aerodynamic/aero-elastic code that includes the structural dynamics of the blades and the Blade Element Momentum (BEM) theory. To model the main aero-elastic behaviour of a real wind turbine...... in the European Commision-sponsored project Model Experiments in Controlled Conditions, (MEXICO) and the computed aero-elastic results are examined against the FLEX code for flow post the Tjereborg 2 MW rotor. To illustrate the optimization technique, three wind turbine rotors of different sizes (the MEXICO 25 k...

  17. Structural Reliability of Wind Turbine Blades

    DEFF Research Database (Denmark)

    Dimitrov, Nikolay Krasimirov

    and design. Reliability-based analysis methods have the potential of being a valuable tool which can improve the state of knowledge by explaining the uncertainties, and form the probabilistic basis for calibration of deterministic design tools. The present thesis focuses on reliability-based design of wind...... turbine blades. The main purpose is to draw a clear picture of how reliability-based design of wind turbines can be done in practice. The objectives of the thesis are to create methodologies for efficient reliability assessment of composite materials and composite wind turbine blades, and to map...... the uncertainties in the processes, materials and external conditions that have an effect on the health of a composite structure. The study considers all stages in a reliability analysis, from defining models of structural components to obtaining the reliability index and calibration of partial safety factors...

  18. Laminar-Turbulent transition on Wind Turbines

    DEFF Research Database (Denmark)

    Martinez Hernandez, Gabriel Gerardo

    The present thesis deals with the study of the rotational effects on the laminar-turbulent transition on wind turbine blades. Linear stability theory is used to formulate the stability equations that include the effect of rotation. The mean flow required as an input to stability computations...... parametrized and adapted to an wind turbine rotor geometry. The blade is resolved in radial sections along which calculations are performed. The obtained mean flow is classified according to the parameters used on the rotating configuration, geometry and operational conditions. The stability diagrams have been...... to define the resultant wave magnitude and direction. The propagation of disturbances in the boundary layers in three dimensional flows is relatively a complicated phenomena. The report discusses the available methods and techniques used to predict the transition location. Some common wind turbine airfoils...

  19. System Reliability for Offshore Wind Turbines

    DEFF Research Database (Denmark)

    Marquez-Dominguez, Sergio; Sørensen, John Dalsgaard

    2013-01-01

    Deeper waters and harsher environments are the main factors that make the electricity generated by offshore wind turbines (OWTs) expensive due to high costs of the substructure, operation & maintenance and installation. The key goal of development is to decrease the cost of energy (CoE). In conse......Deeper waters and harsher environments are the main factors that make the electricity generated by offshore wind turbines (OWTs) expensive due to high costs of the substructure, operation & maintenance and installation. The key goal of development is to decrease the cost of energy (Co...... in inspections or measurements from condition monitoring systems. Finally, an example is established to illustrate the practical application of this framework for jacket type wind turbine substructure considering system effects....

  20. Performance of spanish wind turbines

    International Nuclear Information System (INIS)

    Lago, C.

    1995-01-01

    In this document we can find a statistical evaluation for the wind energy generation from each spanish wind farm referred to 1994, going on with the work that has been carried out since 1992, by initiative of the Wind Energy Division from Renewable Energy Institute. The purpose of this work is to contribute with interesting information for the wind environment and offer a global view from monthly performances of different wind farms. (Author)

  1. Magnus wind turbines as an alternative to the blade ones

    International Nuclear Information System (INIS)

    Bychkov, N M; Dovgal, A V; Kozlov, V V

    2007-01-01

    Experimental and calculated data on a wind turbine equipped with rotating cylinders instead of traditional blades are reported. Optimal parameters and the corresponding operational characteristics of the windwheel are given in comparison with those of the blade wind turbines

  2. OUT Success Stories: Advanced Airfoils for Wind Turbines

    International Nuclear Information System (INIS)

    Jones, J.; Green, B.

    2000-01-01

    New airfoils have substantially increased the aerodynamic efficiency of wind turbines. It is clear that these new airfoils substantially increased energy output from wind turbines. Virtually all new blades built in this country today use these advanced airfoil designs

  3. International Review of Grid Connection Requirements for Wind Turbines

    Energy Technology Data Exchange (ETDEWEB)

    Jauch, Clemens; Soerensen, Poul [Risoe National Laboratory, Roskilde (Denmark). Wind Energy Dept.; Bak-Jensen, Birgitte [Aalborg Univ. (Denmark). Inst. of Energy Technology

    2004-07-01

    Some of the latest and most relevant grid connection requirements for wind turbines of different countries are summarized and discussed. The inherent implications of these requirements for current wind turbine technology are outlined and discussed.

  4. Methods and apparatus for rotor load control in wind turbines

    Science.gov (United States)

    Moroz, Emilian Mieczyslaw

    2006-08-22

    A wind turbine having a rotor, at least one rotor blade, and a plurality of generators, of which a first generator is configured to provide power to an electric grid and a second generator is configured to provide power to the wind turbine during times of grid loss. The wind turbine is configured to utilize power provided by the second generator to reduce loads on the wind turbine during times of grid loss.

  5. Health effects related to wind turbine noise exposure

    DEFF Research Database (Denmark)

    Schmidt, Jesper Hvass; Klokker, Mads

    2014-01-01

    BACKGROUND: Wind turbine noise exposure and suspected health-related effects thereof have attracted substantial attention. Various symptoms such as sleep-related problems, headache, tinnitus and vertigo have been described by subjects suspected of having been exposed to wind turbine noise...... existing statistically-significant evidence indicating any association between wind turbine noise exposure and tinnitus, hearing loss, vertigo or headache. LIMITATIONS: Selection bias and information bias of differing magnitudes were found to be present in all current studies investigating wind turbine...

  6. OPTIMISATION OF WIND TURBINE WITH DIFFUSER USING CFD TOOL

    OpenAIRE

    Mr. K Prakash, R.Sreeju , S.Vijaychandran, A.R.Sridharan

    2017-01-01

    A wind turbine or wind power plant is a device that converts kinetic energy from the wind into electric current. Mechanical energy is simply created when the wind turbine blades spin and a generator is turned, thus producing electricity. Diffuser can increase turbine power output primarily by increasing mass flow rate through the blades because of controlled diffusion of the turbine wake which which lowers the exit plane pressure considerably below atmospheric, and secondarily by reducing bla...

  7. CFD for wind and tidal offshore turbines

    CERN Document Server

    Montlaur, Adeline

    2015-01-01

    The book encompasses novel CFD techniques to compute offshore wind and tidal applications. Computational fluid dynamics (CFD) techniques are regarded as the main design tool to explore the new engineering challenges presented by offshore wind and tidal turbines for energy generation. The difficulty and costs of undertaking experimental tests in offshore environments have increased the interest in the field of CFD which is used to design appropriate turbines and blades, understand fluid flow physical phenomena associated with offshore environments, predict power production or characterise offshore environments, amongst other topics.

  8. Torsional Performance of Wind Turbine Blades

    DEFF Research Database (Denmark)

    Branner, Kim; Berring, Peter; Berggreen, Christian

    2007-01-01

    The present work investigates how well different finite element modeling techniques can predict bending and torsion behavior of a wind turbine blade. Two shell models are investigated. One model has element offsets and the other has the elements at the mid-thickness surfaces of the model. The last...... two models investigated use a combination of shell and solid elements. The results from the numerical investigations are compared with measurements from testing of a section of a full-scale wind turbine blade. It is found that only the combined shell/solid models give reliable results in torsion. Both...

  9. Aero-acoustic Computations of Wind Turbines

    DEFF Research Database (Denmark)

    Shen, Wen Zhong; Michelsen, Jess; Sørensen, Jens Nørkær

    2002-01-01

    A numerical algorithm for acoustic noise generation is extended to 3D flows. The approach involves two parts comprising a viscous incompressible flow part and an inviscid acoustic part. In order to simulate noise generated from a wind turbine, the incompressible and acoustic equations are written...... in polar coordinates. The developed algorithm is combined with a so-called actuator-line technique in which the loading is distributed along lines representing the blade forces. Computations are carried out for the 500kW Nordtank wind turbine equipped with three LM19 blades. ©2001 The American Institute...

  10. Effectiveness of Changing Wind Turbine Cut-in Speed to Reduce Bat Fatalities at Wind Facilities

    Energy Technology Data Exchange (ETDEWEB)

    Huso, Manuela M. P. [Oregon State Univ., Corvallis, OR (United States); Hayes, John P. [Univ. of Florida, Gainesville, FL (United States)

    2009-04-01

    This report details an experiment on the effectiveness of changing wind turbine cut-in speed on reducing bat fatality from wind turbines at the Casselman Wind Project in Somerset County, Pennsylvania.

  11. Wind Turbine Contingency Control Through Generator De-Rating

    Science.gov (United States)

    Frost, Susan; Goebel, Kai; Balas, Mark

    2013-01-01

    Maximizing turbine up-time and reducing maintenance costs are key technology drivers for wind turbine operators. Components within wind turbines are subject to considerable stresses due to unpredictable environmental conditions resulting from rapidly changing local dynamics. In that context, systems health management has the aim to assess the state-of-health of components within a wind turbine, to estimate remaining life, and to aid in autonomous decision-making to minimize damage to the turbine. Advanced contingency control is one way to enable autonomous decision-making by providing the mechanism to enable safe and efficient turbine operation. The work reported herein explores the integration of condition monitoring of wind turbines with contingency control to balance the trade-offs between maintaining system health and energy capture. The contingency control involves de-rating the generator operating point to achieve reduced loads on the wind turbine. Results are demonstrated using a high fidelity simulator of a utility-scale wind turbine.

  12. Crack Monitoring of Operational Wind Turbine Foundations.

    Science.gov (United States)

    Perry, Marcus; McAlorum, Jack; Fusiek, Grzegorz; Niewczas, Pawel; McKeeman, Iain; Rubert, Tim

    2017-08-21

    The degradation of onshore, reinforced-concrete wind turbine foundations is usually assessed via above-ground inspections, or through lengthy excavation campaigns that suspend wind power generation. Foundation cracks can and do occur below ground level, and while sustained measurements of crack behaviour could be used to quantify the risk of water ingress and reinforcement corrosion, these cracks have not yet been monitored during turbine operation. Here, we outline the design, fabrication and field installation of subterranean fibre-optic sensors for monitoring the opening and lateral displacements of foundation cracks during wind turbine operation. We detail methods for in situ sensor characterisation, verify sensor responses against theoretical tower strains derived from wind speed data, and then show that measured crack displacements correlate with monitored tower strains. Our results show that foundation crack opening displacements respond linearly to tower strain and do not change by more than ±5 μ m. Lateral crack displacements were found to be negligible. We anticipate that the work outlined here will provide a starting point for real-time, long-term and dynamic analyses of crack displacements in future. Our findings could furthermore inform the development of cost-effective monitoring systems for ageing wind turbine foundations.

  13. Advantages on monitoring wind turbine nacelle oscillation

    DEFF Research Database (Denmark)

    Skrimpas, Georgios Alexandros; Marhadi, Kun Saptohartyadi; Hilmisson, Reynir

    2015-01-01

    Nacelle oscillation monitoring, where accelerometers are mounted on the nacelle frame, is integral part of modern condition monitoring systems towards holistic and consistent health assessment of wind turbines. It enables detection of abnormal behavior associated to increased stresses and vibrati......Nacelle oscillation monitoring, where accelerometers are mounted on the nacelle frame, is integral part of modern condition monitoring systems towards holistic and consistent health assessment of wind turbines. It enables detection of abnormal behavior associated to increased stresses...... and vibrations on blades, tower and drive train components, which may jeopardize their working condition. The present paper deals with the comparison and analysis of vibration signals from wind turbines subjected to various failure modes and operating conditions, such as blade misalignment, pitch malfunction......, ice accretion, damaged blade tips and yaw system defects. Theoretical analysis of nacelle movement at down wind and lateral direction is presented along with field results from multi megawatt wind turbines. Additionally the paper discusses the employment of nacelle accelerometers for cross reference...

  14. Canadian Wind Energy Association small wind conference proceedings : small wind policy developments (turbines of 300 kW or less)

    International Nuclear Information System (INIS)

    2005-01-01

    The small wind session at the Canadian Wind Energy Association's (CanWEA) annual conference addressed policies affecting small wind, such as net metering, advanced renewable tariffs and interconnections. It also addressed CanWEA's efforts in promoting small wind turbines, particularly in remote northern communities, small businesses and within the residential sector. Small wind systems are typically installed in remote communities to offset utility supplied electricity at the retail price level. In certain circumstances, small wind and hybrid systems can produce electricity at less than half the cost of traditional electricity sources, which in remote communities is typically diesel generators. Small wind turbines require different materials and technologies than large wind turbines. They also involve different local installation requirements, different by-laws, tax treatment and environmental assessments. Small wind turbines are typically installed for a range of factors, including energy independence, energy price stability and to lower environmental impacts of traditional power generation. The small wind session at the conference featured 14 presentations, of which 4 have been catalogued separately for inclusion in this database. tabs., figs

  15. Power Electronics as key technology in wind turbines

    DEFF Research Database (Denmark)

    Blaabjerg, Frede

    2005-01-01

    This paper discuss the development in wind turbines in a two-decade perspective looking at the technology based on track records. Different power electronic topologies for interfacing the wind turbine to the grid are discussed and related to the possibility for the wind turbine to act as a power...

  16. Analysis of horizontal axis wind turbine blade using CFD | Nigam ...

    African Journals Online (AJOL)

    Blade is very essential part of HAWT (horizontal axis wind turbine). Forces for Lift and drag on the blade has an important role in the wind turbine performance. The main purpose of this work is to perform CFD analysis of a blade and airfoil of wind turbine using k-ω SST model. In this present study NACA 634 -221 airfoil ...

  17. Load alleviation on wind turbine blades using variable geometry

    DEFF Research Database (Denmark)

    Basualdo, Santiago

    2005-01-01

    ) wind turbines, which mainly operate under this flow condition. The results show evident reductions in the airfoil displacements by using simple control strategies having the airfoil position and its first and second derivatives as input, especially at the system's eigenfrequency. The use of variable...... in loads in real wind turbines. Keywords: Variable Geometry, Wind Turbine, Load Alleviation, Fatigue Load, Trailing Edge Flap....

  18. Structured Linear Parameter Varying Control of Wind Turbines

    DEFF Research Database (Denmark)

    Adegas, Fabiano Daher; Sloth, Christoffer; Stoustrup, Jakob

    2012-01-01

    High performance and reliability are required for wind turbines to be competitive within the energy market. To capture their nonlinear behavior, wind turbines are often modeled using parameter-varying models. In this chapter, a framework for modelling and controller design of wind turbines is pre...

  19. Duration Test Report for the Entegrity EW50 Wind Turbine

    Energy Technology Data Exchange (ETDEWEB)

    Smith, J.; Huskey, A.; Jager, D.; Hur, J.

    2012-12-01

    This report summarizes the results of a duration test that NREL conducted on the Entegrity EW50 wind turbine. This test was conducted in accordance with the International Electrotechnical Commissions' (IEC) standard, Wind Turbine Generator System Part 2: Design requirements for small wind turbines, IEC 61400-2 Ed.2.0, 2006-03.

  20. Evolution of wind towards wind turbine

    NARCIS (Netherlands)

    Giyanani, A.H.; Bierbooms, W.A.A.M.; Van Bussel, G.J.W.

    2015-01-01

    Remote sensing of the atmospheric variables with the use of LiDAR is a relatively new technology field for wind resource assessment in wind energy. The validation of LiDAR measurements and comparisons is of high importance for further applications of the data.

  1. Transient LES of an offshore wind turbine

    Directory of Open Access Journals (Sweden)

    L. Vollmer

    2017-12-01

    Full Text Available The estimation of the cost of energy of offshore wind farms has a high uncertainty, which is partly due to the lacking accuracy of information on wind conditions and wake losses inside of the farm. Wake models that aim to reduce the uncertainty by modeling the wake interaction of turbines for various wind conditions need to be validated with measurement data before they can be considered as a reliable estimator. In this paper a methodology that enables a direct comparison of modeled with measured flow data is evaluated. To create the simulation data, a model chain including a mesoscale model, a large-eddy-simulation (LES model and a wind turbine model is used. Different setups are compared to assess the capability of the method to reproduce the wind conditions at the hub height of current offshore wind turbines. The 2-day-long simulation of the ambient wind conditions and the wake simulation generally show good agreements with data from a met mast and lidar measurements, respectively. Wind fluctuations due to boundary layer turbulence and synoptic-scale motions are resolved with a lower representation of mesoscale fluctuations. Advanced metrics to describe the wake shape and development are derived from simulations and measurements but a quantitative comparison proves to be difficult due to the scarcity and the low sampling rate of the available measurement data. Due to the implementation of changing synoptic wind conditions in the LES, the methodology could also be beneficial for case studies of wind farm performance or wind farm control.

  2. Wind Turbine Generator System Power Quality Test Report for the Gaia Wind 11-kW Wind Turbine

    Energy Technology Data Exchange (ETDEWEB)

    Curtis, A.; Gevorgian, V.

    2011-07-01

    This report details the power quality test on the Gaia Wind 11-kW Wind Turbine as part of the U.S. Department of Energy's Independent Testing Project. In total five turbines are being tested as part of the project. Power quality testing is one of up to five test that may be performed on the turbines including power performance, safety and function, noise, and duration tests. The results of the testing provide manufacturers with reports that may be used for small wind turbine certification.

  3. Wind tunnel tests of a free yawing downwind wind turbine

    DEFF Research Database (Denmark)

    Verelst, David Robert; Larsen, Torben J.; van Wingerden, J.W.

    2012-01-01

    During February and April 2012 a series of wind tunnel tests were performed at the TU Delft Open Jet Facility (OJF) with a three bladed downwind wind turbine and a rotor radius of 0.8 meters. The setup includes an off the shelf three bladed hub, nacelle and generator on which relatively flexible ...... in free yawing conditions. Further, the effect of the tower shadow passage on the blade flapwise strain measurement is evaluated. Finally, data from the experiment is compared with preliminary simulations using DTU Wind Energy's aeroelastic simulation program HAWC2.......During February and April 2012 a series of wind tunnel tests were performed at the TU Delft Open Jet Facility (OJF) with a three bladed downwind wind turbine and a rotor radius of 0.8 meters. The setup includes an off the shelf three bladed hub, nacelle and generator on which relatively flexible...

  4. Optimum Operational Parameters for Yawed Wind Turbines

    Directory of Open Access Journals (Sweden)

    David A. Peters

    2011-01-01

    Full Text Available A set of systematical optimum operational parameters for wind turbines under various wind directions is derived by using combined momentum-energy and blade-element-energy concepts. The derivations are solved numerically by fixing some parameters at practical values. Then, the interactions between the produced power and the influential factors of it are generated in the figures. It is shown that the maximum power produced is strongly affected by the wind direction, the tip speed, the pitch angle of the rotor, and the drag coefficient, which are specifically indicated by figures. It also turns out that the maximum power can take place at two different optimum tip speeds in some cases. The equations derived herein can also be used in the modeling of tethered wind turbines which can keep aloft and deliver energy.

  5. Wind Climate Parameters for Wind Turbine Fatigue Load Assessment

    DEFF Research Database (Denmark)

    Toft, Henrik Stensgaard; Svenningsen, Lasse; Moser, Wolfgang

    2016-01-01

    established from the on-site distribution functions of the horizontal mean wind speeds, the 90% quantile of turbulence along with average values of vertical wind shear and air density and the maximum flow inclination. This paper investigates the accuracy of fatigue loads estimated using this equivalent wind...... climate required by the current design standard by comparing damage equivalent fatigue loads estimated based on wind climate parameters for each 10 min time-series with fatigue loads estimated based on the equivalent wind climate parameters. Wind measurements from Boulder, CO, in the United States...... and Høvsøre in Denmark have been used to estimate the natural variation in the wind conditions between 10 min time periods. The structural wind turbine loads have been simulated using the aero-elastic model FAST. The results show that using a 90% quantile for the turbulence leads to an accurate assessment...

  6. Effects of Icing on Wind Turbine Fatigue Loads

    International Nuclear Information System (INIS)

    Frohboese, Peter; Anders, Andreas

    2007-01-01

    The external conditions occurring at cold climate sites will affect wind turbines in different ways. The effects of ice accretion on wind turbines and the influence on the turbine fatigue loads are examined. The amount of icing prior to turbine installation needs to be estimated by using standard measurement data and considering the geometry of the proposed turbine. A procedure to calculate the expected ice accretion on wind turbines out of standard measurement data is explained and the results are discussed. Different parameters to describe the accreted ice on the turbine are examined separately in a fatigue load calculation. The results of the fatigue load calculation are discussed and selected cases are presented

  7. Model-based control of a ballast-stabilized floating wind turbine exposed to wind and waves

    Energy Technology Data Exchange (ETDEWEB)

    Christiansen, Soeren

    2013-01-15

    The wind turbine is a commercial product which is competing against other sources of energy, such as coal and gas. This competition drives a constant development to reduce costs and improve efficiency in order to reduce the total cost of the energy. The latest offshore development is the floating wind turbine, for water depths beyond 50 meters where winds are stronger and less turbulent. A floating wind turbine is subject to not only aerodynamics and wind induced loads, but also to hydrodynamics and wave induced loads. In contrast to a bottom fixed wind turbine, the floating structure, the hydrodynamics and the loads change the dynamic behavior of a floating wind turbine. Consequently, conventional wind turbine control cause instabilities on floating wind turbines. This work addresses the control of a floating spar buoy wind turbine, and focuses on the impact of the additional platform dynamics. A time varying control model is presented based on the wind speed and wave frequency. Estimates of the wind speed and wave frequency are used as scheduling variables in a gain scheduled linear quadratic controller to improve the electrical power production while reducing fatigue. To address the problem of negative damped fore-aft tower motion, additional control loops are suggested which stabilize the response of the onshore controller and reduce the impact of the wave induced loads. This research is then extended to model predictive control, to further address wave disturbances. In the context of control engineering, the dynamics and disturbances of a floating wind turbine have been identified and modeled. The objectives of maximizing the production of electrical power and minimizing fatigue have been reached by using advanced methods of estimation and control. (Author)

  8. 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

  9. Wind Turbine Acoustic Investigation: Infrasound and Low-Frequency Noise--A Case Study

    Science.gov (United States)

    Ambrose, Stephen E.; Rand, Robert W.; Krogh, Carmen M. E.

    2012-01-01

    Wind turbines produce sound that is capable of disturbing local residents and is reported to cause annoyance, sleep disturbance, and other health-related impacts. An acoustical study was conducted to investigate the presence of infrasonic and low-frequency noise emissions from wind turbines located in Falmouth, Massachusetts, USA. During the…

  10. Built-Environment Wind Turbine Roadmap

    Energy Technology Data Exchange (ETDEWEB)

    Smith, J.; Forsyth, T.; Sinclair, K.; Oteri, F.

    2012-11-01

    Although only a small contributor to total electricity production needs, built-environment wind turbines (BWTs) nonetheless have the potential to influence the public's consideration of renewable energy, and wind energy in particular. Higher population concentrations in urban environments offer greater opportunities for project visibility and an opportunity to acquaint large numbers of people to the advantages of wind projects on a larger scale. However, turbine failures will be equally visible and could have a negative effect on public perception of wind technology. This roadmap provides a framework for achieving the vision set forth by the attendees of the Built-Environment Wind Turbine Workshop on August 11 - 12, 2010, at the U.S. Department of Energy's National Renewable Energy Laboratory. The BWT roadmap outlines the stakeholder actions that could be taken to overcome the barriers identified. The actions are categorized as near-term (0 - 3 years), medium-term (4 - 7 years), and both near- and medium-term (requiring immediate to medium-term effort). To accomplish these actions, a strategic approach was developed that identifies two focus areas: understanding the built-environment wind resource and developing testing and design standards. The authors summarize the expertise and resources required in these areas.

  11. Model Predictive Control with Constraints of a Wind Turbine

    DEFF Research Database (Denmark)

    Henriksen, Lars Christian; Poulsen, Niels Kjølstad

    2007-01-01

    Model predictive control of wind turbines offer a more systematic approach of constructing controllers that handle constraints while focusing on the main control objective. In this article several controllers are designed for different wind conditions and appropriate switching conditions ensure...... an efficient control of the wind turbine over the entire range of wind speeds. Both onshore and floating offshore wind turbines are tested with the controllers....

  12. Large wind turbine development in Europe

    Energy Technology Data Exchange (ETDEWEB)

    Zervos, A. [Center for Renewable Energy Sources, Attikis (Greece)

    1996-12-31

    During the last few years we have witnessed in Europe the development of a new generation of wind turbines ranging from 1000-1500 kW size. They are presently being tested and they are scheduled to reach the market in late 1996 early 1997. The European Commission has played a key role by funding the research leading to the development of these turbines. The most visible initiative at present is the WEGA program - the development, together with Europe`s leading wind industry players of a new generation of turbines in the MW range. By the year 1997 different European manufacturers will have introduced almost a dozen new MW machine types to the international market, half of them rated at 1.5 MW. 3 refs., 3 tabs.

  13. Wind turbine reliability :understanding and minimizing wind turbine operation and maintenance costs.

    Energy Technology Data Exchange (ETDEWEB)

    Walford, Christopher A. (Global Energy Concepts. Kirkland, WA)

    2006-03-01

    Wind turbine system reliability is a critical factor in the success of a wind energy project. Poor reliability directly affects both the project's revenue stream through increased operation and maintenance (O&M) costs and reduced availability to generate power due to turbine downtime. Indirectly, the acceptance of wind-generated power by the financial and developer communities as a viable enterprise is influenced by the risk associated with the capital equipment reliability; increased risk, or at least the perception of increased risk, is generally accompanied by increased financing fees or interest rates. This paper outlines the issues relevant to wind turbine reliability for wind turbine power generation projects. The first sections describe the current state of the industry, identify the cost elements associated with wind farm O&M and availability and discuss the causes of uncertainty in estimating wind turbine component reliability. The latter sections discuss the means for reducing O&M costs and propose O&M related research and development efforts that could be pursued by the wind energy research community to reduce cost of energy.

  14. Torsional Performance of Wind Turbine Blades

    DEFF Research Database (Denmark)

    Branner, Kim; Berring, Peter; Berggreen, Christian

    2007-01-01

    The present work investigates how well different finite element modeling techniques can predict bending and torsion behavior of a wind turbine blade. Two shell models are investigated. One model has element offsets and the other has the elements at the mid-thickness surfaces of the model. The las...

  15. Wide band characterization of wind turbine reactors

    DEFF Research Database (Denmark)

    Holdyk, Andrzej; Arana Aristi, Ivan; Holbøll, Joachim

    2013-01-01

    This paper presents the results of field measure-ments of the impedance of two commercial available wind turbine reactors, performed by a sweep frequency response analyzer, sFRA. The measurements were taken in the frequency range from 20Hz to 20MHz. Comparable frequency behavior was found in all ...

  16. Results of a wind turbine FDI competition

    DEFF Research Database (Denmark)

    Odgaard, Peter Fogh; Stoustrup, Jakob

    2012-01-01

    In this paper some newly published methods for fault detection and isolation developed for a wind turbine benchmark model are tested, compared and evaluated. These methods have been presented as a part of an international competition. The tested methods cover different types of fault detection...

  17. Floating offshore wind turbines for shallow waters

    NARCIS (Netherlands)

    Bulder, B.H.; Henderson, A.; Huijsmans, R.H.M.; Peeringa, J.M.; Pierik, J.T.G.; Snijders, E.J.B.; Hees, M.Th. van; Wijnants, G.H.; Wolf, M.J.

    2003-01-01

    Bottom mounted Offshore wind turbines seem to have a promising future but they are restricted to shallow waters of Northern Europe. Many projects are planned or are in the phase of construction on the North Sea and the Baltic Sea. All projects that are planned have a water depth up to approximately

  18. Models for wind turbines - a collection

    DEFF Research Database (Denmark)

    2002-01-01

    This report is a collection of notes which were intended to be short communications. Main target of the work presented is to supply new approaches to stability investigations of wind turbines. The author's opinion is that an efficient, systematicstability analysis can not be performed for large...

  19. Stochastic Modeling Of Wind Turbine Drivetrain Components

    DEFF Research Database (Denmark)

    Rafsanjani, Hesam Mirzaei; Sørensen, John Dalsgaard

    2014-01-01

    reliable components are needed for wind turbine. In this paper focus is on reliability of critical components in drivetrain such as bearings and shafts. High failure rates of these components imply a need for more reliable components. To estimate the reliability of these components, stochastic models...

  20. Review paper on wind turbine aerodynamics

    DEFF Research Database (Denmark)

    Hansen, Martin Otto Laver; Aagaard Madsen, Helge

    2011-01-01

    The paper describes the development and description of the aerodynamic models used to estimate the aerodynamic loads on wind turbine constructions. This includes a status of the capabilities of computation fluid dynamics and the need for reliable airfoil data for the simpler engineering models....... © 2011 American Society of Mechanical Engineers....

  1. Root region airfoil for wind turbine

    Science.gov (United States)

    Tangler, James L.; Somers, Dan M.

    1995-01-01

    A thick airfoil for the root region of the blade of a wind turbine. The airfoil has a thickness in a range from 24%-26% and a Reynolds number in a range from 1,000,000 to 1,800,000. The airfoil has a maximum lift coefficient of 1.4-1.6 that has minimum sensitivity to roughness effects.

  2. Predicting annoyance by wind turbine noise

    NARCIS (Netherlands)

    Janssen, S.A.; Vos, H.; Eisses, A.R.; Pedersen, E.

    2010-01-01

    While wind turbines have beneficial effects for the environment, they inevitably generate environmental noise. In order to protect residents against unacceptable levels of noise, exposure-response relationships are needed to predict the expected percentage of people annoyed or highly annoyed at a

  3. Infrasound from Wind Turbines Could Affect Humans

    Science.gov (United States)

    Salt, Alec N.; Kaltenbach, James A.

    2011-01-01

    Wind turbines generate low-frequency sounds that affect the ear. The ear is superficially similar to a microphone, converting mechanical sound waves into electrical signals, but does this by complex physiologic processes. Serious misconceptions about low-frequency sound and the ear have resulted from a failure to consider in detail how the ear…

  4. Aero-Acoustic Computations of Wind Turbines

    DEFF Research Database (Denmark)

    Zhu, Wei Jun

    2008-01-01

    both for laminar and turbulent flows. Results have shown that sound generation is due to the unsteadiness of the flow field and the spectrum of sound has a strong relation with fluctuating forces on the solid body. Flow and acoustic simulation were also carried out for a wind turbine where general...

  5. A New Fault Diagnosis Algorithm for PMSG Wind Turbine Power Converters under Variable Wind Speed Conditions

    Directory of Open Access Journals (Sweden)

    Yingning Qiu

    2016-07-01

    Full Text Available Although Permanent Magnet Synchronous Generator (PMSG wind turbines (WTs mitigate gearbox impacts, they requires high reliability of generators and converters. Statistical analysis shows that the failure rate of direct-drive PMSG wind turbines’ generators and inverters are high. Intelligent fault diagnosis algorithms to detect inverters faults is a premise for the condition monitoring system aimed at improving wind turbines’ reliability and availability. The influences of random wind speed and diversified control strategies lead to challenges for developing intelligent fault diagnosis algorithms for converters. This paper studies open-circuit fault features of wind turbine converters in variable wind speed situations through systematic simulation and experiment. A new fault diagnosis algorithm named Wind Speed Based Normalized Current Trajectory is proposed and used to accurately detect and locate faulted IGBT in the circuit arms. It is compared to direct current monitoring and current vector trajectory pattern approaches. The results show that the proposed method has advantages in the accuracy of fault diagnosis and has superior anti-noise capability in variable wind speed situations. The impact of the control strategy is also identified. Experimental results demonstrate its applicability on practical WT condition monitoring system which is used to improve wind turbine reliability and reduce their maintenance cost.

  6. Low wind speed wind turbine in DIY version

    OpenAIRE

    Van den Bossche, Alex

    2013-01-01

    Wind energy has still a place, as it can generate power in the winter, when less sun is available and when the wind speed is higher. This paper proposes a solution for low cost blades from a polyethylene pipe (PE) and a low cost electric bike generator, which is possible to realize by a do it yourself (DIY) person. It is intended as low wind speed wind turbine (LWWT). The design is rather optimized towards a low cost/swept area, rather than the cost/nominal power. It uses a variant on the fur...

  7. Wind Turbine Optimization with WISDEM

    Energy Technology Data Exchange (ETDEWEB)

    Dykes, Katherine L [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Damiani, Rick R [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Graf, Peter A [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Scott, George N [National Renewable Energy Laboratory (NREL), Golden, CO (United States); King, Ryan N [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Guo, Yi [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Quick, Julian [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Sethuraman, Latha [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Veers, Paul S [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Ning, Andrew [Brigham Young University

    2018-01-03

    This presentation for the Fourth Wind Energy Systems Engineering Workshop explains the NREL wind energy systems engineering initiative-developed analysis platform and research capability to capture important system interactions to achieve a better understanding of how to improve system-level performance and achieve system-level cost reductions. Topics include Wind-Plant Integrated System Design and Engineering Model (WISDEM) and multidisciplinary design analysis and optimization.

  8. Semiconductor Laser Wind Lidar for Turbine Control

    DEFF Research Database (Denmark)

    Hu, Qi

    This thesis describes an experimentally oriented study of continuous wave (CW) coherent Doppler lidar system design. The main application is remote wind sensing for active wind turbine control using nacelle mounted lidar systems; and the primary focus is to devise an industrial instrument that can...... been investigated. The results hows a much less SNR penalty than expected, due to a finite signal bandwidth of the wind signal.For applications such as active yaw or pitch control, multiple lines of sight are required of the lidar system. Thus, two different beam steering methods have been investigated...... improve the efficiency of harvesting wind energy in commercial wind farms. This work attempts to provide a complete investigation of all the necessary building blocks in a CW wind lidar, from the light source to the optical transceiver. The basic concept of Doppler lidar is introduced along with a brief...

  9. Power Performance Test Report for the SWIFT Wind Turbine

    Energy Technology Data Exchange (ETDEWEB)

    Mendoza, I.; Hur, J.

    2012-12-01

    This report summarizes the results of a power performance test that NREL conducted on the SWIFT wind turbine. This test was conducted in accordance with the International Electrotechnical Commission's (IEC) standard, Wind Turbine Generator Systems Part 12: Power Performance Measurements of Electricity Producing Wind Turbines, IEC 61400-12-1 Ed.1.0, 2005-12. However, because the SWIFT is a small turbine as defined by IEC, NREL also followed Annex H that applies to small wind turbines. In these summary results, wind speed is normalized to sea-level air density.

  10. Life cycle assessment of a floating offshore wind turbine

    Energy Technology Data Exchange (ETDEWEB)

    Weinzettel, Jan [Department of Electrotechnology, Faculty of Electrical Engineering, Czech Technical University in Prague, Technicka 2, Praha 166 27 (Czech Republic); Charles University in Prague Environment Center, U Krize 8, Prague 158 00 (Czech Republic); Reenaas, Marte; Solli, Christian [Industrial Ecology Programme, Norwegian University of Science and Technology (NTNU), 7491 Trondheim (Norway); Hertwich, Edgar G. [Industrial Ecology Programme, Norwegian University of Science and Technology (NTNU), 7491 Trondheim (Norway); Department of Energy and Process Engineering, Norwegian University of Science and Technology (NTNU), 7491 Trondheim (Norway)

    2009-03-15

    A development in wind energy technology towards higher nominal power of the wind turbines is related to the shift of the turbines to better wind conditions. After the shift from onshore to offshore areas, there has been an effort to move further from the sea coast to the deep water areas, which requires floating windmills. Such a concept brings additional environmental impact through higher material demand. To evaluate additional environmental burdens and to find out whether they can be rebalanced or even offset by better wind conditions, a prospective life cycle assessment (LCA) study of one floating concept has been performed and the results are presented in this paper. A comparison with existing LCA studies of conventional offshore wind power and electricity from a natural gas combined cycle is presented. The results indicate similar environmental impacts of electricity production using floating wind power plants as using non-floating offshore wind power plants. The most important stage in the life cycle of the wind power plants is the production of materials. Credits that are connected to recycling these materials at the end-of-life of the power plant are substantial. (author)

  11. Grid fault and design-basis for wind turbines. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Hansen, A.D.; Cutululis, N.A.; Markou, H.; Soerensen, Poul; Iov, F.

    2010-01-15

    This is the final report of a Danish research project 'Grid fault and design-basis for wind turbines'. The objective of this project has been to assess and analyze the consequences of the new grid connection requirements for the fatigue and ultimate structural loads of wind turbines. The fulfillment of the grid connection requirements poses challenges for the design of both the electrical system and the mechanical structure of wind turbines. The development of wind turbine models and novel control strategies to fulfill the TSO's requirements are of vital importance in this design. Dynamic models and different fault ride-through control strategies have been developed and assessed in this project for three different wind turbine concepts (active stall wind turbine, variable speed doublyfed induction generator wind turbine, variable speed multipole permanent magnet wind turbine). A computer approach for the quantification of the wind turbines structural loads caused by the fault ride-through grid requirement, has been proposed and exemplified for the case of an active stall wind turbine. This approach relies on the combination of knowledge from complimentary simulation tools, which have expertise in different specialized design areas for wind turbines. In order to quantify the impact of the grid faults and grid requirements fulfillment on wind turbines structural loads and thus on their lifetime, a rainflow and a statistical analysis for fatigue and ultimate structural loads, respectively, have been performed and compared for two cases, i.e. one when the turbine is immediately disconnected from the grid when a grid fault occurs and one when the turbine is equipped with a fault ride-through controller and therefore it is able to remain connected to the grid during the grid fault. Different storm control strategies, that enable variable speed wind turbines to produce power at wind speeds higher than 25m/s and up to 50m/s without substantially increasing

  12. Wind/Wave Misalignment in the Loads Analysis of a Floating Offshore Wind Turbine: Preprint

    Energy Technology Data Exchange (ETDEWEB)

    Barj, L.; Stewart, S.; Stewart, G.; Lackner, M.; Jonkman, J.; Robertson, A.

    2014-02-01

    Wind resources far from the shore and in deeper seas have encouraged the offshore wind industry to look into floating platforms. The International Electrotechnical Commission (IEC) is developing a new technical specification for the design of floating offshore wind turbines that extends existing design standards for land-based and fixed-bottom offshore wind turbines. The work summarized in this paper supports the development of best practices and simulation requirements in the loads analysis of floating offshore wind turbines by examining the impact of wind/wave misalignment on the system loads under normal operation. Simulations of the OC3-Hywind floating offshore wind turbine system under a wide range of wind speeds, significant wave heights, peak-spectral periods and wind/wave misalignments have been carried out with the aero-servo-hydro-elastic tool FAST [4]. The extreme and fatigue loads have been calculated for all the simulations. The extreme and fatigue loading as a function of wind/wave misalignment have been represented as load roses and a directional binning sensitivity study has been carried out. This study focused on identifying the number and type of wind/wave misalignment simulations needed to accurately capture the extreme and fatigue loads of the system in all possible metocean conditions considered, and for a down-selected set identified as the generic US East Coast site. For this axisymmetric platform, perpendicular wind and waves play an important role in the support structure and including these cases in the design loads analysis can improve the estimation of extreme and fatigue loads. However, most structural locations see their highest extreme and fatigue loads with aligned wind and waves. These results are specific to the spar type platform, but it is expected that the results presented here will be similar to other floating platforms.

  13. Control of Next Generation Aircraft and Wind Turbines

    Science.gov (United States)

    Frost, Susan

    2010-01-01

    The first part of this talk will describe some of the exciting new next generation aircraft that NASA is proposing for the future. These aircraft are being designed to reduce aircraft fuel consumption and environmental impact. Reducing the aircraft weight is one approach that will be used to achieve these goals. A new control framework will be presented that enables lighter, more flexible aircraft to maintain aircraft handling qualities, while preventing the aircraft from exceeding structural load limits. The second part of the talk will give an overview of utility-scale wind turbines and their control. Results of collaboration with Dr. Balas will be presented, including new theory to adaptively control the turbine in the presence of structural modes, with the focus on the application of this theory to a high-fidelity simulation of a wind turbine.

  14. Spatial planning of wind turbines

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2004-01-01

    This paper proposes guidelines for spatial planning for wind power, based on experience with spatial planning in Belgium, Denmark, France and the Netherlands. In addition experiences from Germany and Ireland have been used. This guidelines quotes all decisive criteria for successful implementation of wind energy: landscape integration, stakeholders involvement, noise and distance from buildings. (author)

  15. Electrical Aspects of Wind Turbines

    DEFF Research Database (Denmark)

    Chen, Zhe; Blaabjerg, Frede

    2009-01-01

    This is the most authoritative single volume on offshore wind power yet published. Distinguished experts, mainly from Europe's leading universities, have contributed a collection of peer reviewed papers on the interfaces between wind power technology and marine engineering. The range of issues...

  16. Offshore Wind Turbine Foundation Design

    DEFF Research Database (Denmark)

    Passon, Patrik

    Offshore wind energy has greatly matured during the last decade with an annually installed energy capacity exceeding 1 GW. A key factor for further large-scale development of offshore wind energy is a cost of energy reduction. Given for example the drop in oil price since summer 2014, which has c...

  17. Investigation of transient models and performances for a doubly fed wind turbine under a grid fault

    DEFF Research Database (Denmark)

    Wang, M.; Zhao, B.; Li, H.

    2011-01-01

    of the grid-side converter and the rotor-side converter of DFIG. Secondly, the transient performances of the presented doubly fed wind turbine under a grid fault were compared and evaluated with different equivalent models, parameters and initial operational conditions. And thirdly, the effects of the active......In order to investigate the impacts of the integration of wind farms into utilities network, it is necessary to analyze the transient performances of wind turbine generation systems (WTGS) with the appropriate transient models. According to the grid code requirements for a wind turbine with doubly...... trip time. Firstly, the different mathematical models of the doubly fed wind turbine were presented, including the electromagnetic transient models of DFIG, a one-mass lumped model, a two-mass shaft flexible model of the wind turbine drive train system, and the power decoupling control strategies...

  18. Dynamic wind turbine models in power system simulation tool

    DEFF Research Database (Denmark)

    Hansen, Anca D.; Iov, Florin; Sørensen, Poul

    This report presents a collection of models and control strategies developed and implemented in the power system simulation tool PowerFactory DIgSILENT for different wind turbine concepts. It is the second edition of Risø-R-1400(EN) and it gathers and describes a whole wind turbine model database...... speed doubly-fed induction generator wind turbine concept 3. Variable speed multi-pole permanent magnet synchronous generator wind turbine concept These wind turbine concept models can be used and even extended for the study of different aspects, e.g. the assessment of power quality, control strategies......, connection of the wind turbine at different types of grid and storage systems. Different control strategies have been developed and implemented for these wind turbine concepts, their performance in normal or fault operation being assessed and discussed by means of simulations. The described control...

  19. Wind Turbine Generator System Acoustic Noise Test Report for the ARE 442 Wind Turbine

    Energy Technology Data Exchange (ETDEWEB)

    Huskey, A.; van Dam, J.

    2010-11-01

    This test was conducted on the ARE 442 as part of the U.S. Department of Energy's (DOE's) Independent Testing project. This project was established to help reduce the barriers of wind energy expansion by providing independent testing results for small turbines. In total, five turbines are being tested at the National Wind Technology Center (NWTC) as a part of this project. Acoustic noise testing is one of up to five tests that may be performed on the turbines, including duration, safety and function, power performance, and power quality tests. The acoustic noise test was conducted to the IEC 61400-11 Edition 2.1.

  20. On the Turbulent Mixing in Horizontal Axis Wind Turbine Wakes

    NARCIS (Netherlands)

    Lignarolo, L.E.M.

    2016-01-01

    The wake flow of a horizontal axis wind turbine is characterised by lower wind speed and higher turbulence than the free-stream conditions. When clustered in large wind farms, wind turbines regularly operate inside the wake of one or more upstream machines. This is a major cause of energy production

  1. Observer Backstepping Control for Variable Speed Wind Turbine

    DEFF Research Database (Denmark)

    Galeazzi, Roberto; Gryning, Mikkel Peter Sidoroff; Blanke, Mogens

    2013-01-01

    This paper presents an observer backstepping controller as feasible solution to variable speed control of wind turbines to maximize wind power capture when operating between cut-in and rated wind speeds. The wind turbine is modeled as a two-mass drive-train system controlled by the generator torq...

  2. Observer Backstepping Control for Variable Speed Wind Turbine

    DEFF Research Database (Denmark)

    Galeazzi, Roberto; Gryning, Mikkel Peter Sidoroff; Blanke, Mogens

    2013-01-01

    This paper presents an observer backstepping controller as feasible solution to variable speed control of wind turbines to maximize wind power capture when operating between cut-in and rated wind speeds. The wind turbine is modeled as a two-mass drive-train system controlled by the generator torque...

  3. Ecodesign framework for developing wind turbines

    DEFF Research Database (Denmark)

    Bonou, Alexandra; Skelton, Kristen; Olsen, Stig Irving

    2016-01-01

    and size, in response to increasing global market demands. Planning, implementing, monitoring, documenting and communicating product related environmental activities of wind turbines in a life cycle management context is the focal point of this article. The development and application of an ecodesign......Despite a wind turbines perceived environmental benefits, there are still many improvements that can be made in the product development process to improve its environmental performance across life cycles. This is especially important as the wind power industry continues to grow, both in volume...... such as workshops, pilots, interviews and life cycle assessment were applied. The ecodesign framework was aligned with the company's formal product lifecycle management process. When combined with life cycle assessment, the framework can identify potential environmental improvements and contribute to coherent...

  4. 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.

  5. The flow upstream of a row of aligned wind turbine rotors and its effect on power production

    DEFF Research Database (Denmark)

    Meyer Forsting, Alexander Raul; Troldborg, Niels; Gaunaa, Mac

    2017-01-01

    The blockage developing in front of a laterally aligned row of wind turbines and its impact on power production over a single turbine was analysed using two different numerical methods. The inflow direction was varied from orthogonal to the row until 45◦, with the turbines turning into the wind, ...

  6. Simulation model of an active stall wind turbine controller

    Energy Technology Data Exchange (ETDEWEB)

    Jauch, C.; Hansen, A.D.; Soerensen, P. [Risoe National Lab., Wind Energy Dept., Rosilde (Denmark); Blaabjerg, F. [Aalborg Univ., Inst. of Energy Technology (Denmark)

    2004-07-01

    This paper describes an active stall wind turbine controller. The objective is to develop a general model of an active stall controller in order to simulate the operation of grid connected active stall wind turbines. The active stall turbine concept and its control strategies are presented and evaluated on the basis of simulations. The presented controller is described for continuous operation under all wind speeds from start-up wind speed to shut doven wind speed. Due to its parametric implementation it is general i.e. it can represent different active stall wind turbine controllers and can be implemented in different simulation tools. (au)

  7. Turbine Control Strategies for Wind Farm Power Optimization

    DEFF Research Database (Denmark)

    Mirzaei, Mahmood; Göçmen Bozkurt, Tuhfe; Giebel, Gregor

    2015-01-01

    and wind farms. One way of achieving these goals is to optimize the power generated by a wind farm. One optimization method is to choose appropriate operating points for the individual wind turbines in the farm. We have made three models of a wind farm based on three difference control strategies...... are different. This means that choosing an appropriate control strategy for the individual wind turbines will result in an increased power production of the wind farm........ Basically, the control strategies determine the steady state operating points of the wind turbines. Except the control strategies of the individual wind turbines, the wind farm models are similar. Each model consists of a row of 5MW reference wind turbines. In the models we are able to optimize...

  8. Minimum Thrust Load Control for Floating Wind Turbine

    DEFF Research Database (Denmark)

    Christiansen, Søren; Bak, Thomas; Knudsen, Torben

    2012-01-01

    — Offshore wind energy capitalizes on the higher and less turbulent wind at sea. Shallow water sites are profitable for deployment of monopile wind turbines at water depths of up to 30 meters. Beyond 30 meters, the wind is even stronger and less turbulent. At these depths, floating wind turbines...... become profitable, capable of accessing unexploited wind resources while reaching regions of new consumers. However, floating wind turbines are subject to reduced structural stiffness which results in instabilities when standard wind turbine control systems are applied. Based on optimal control, this paper...... presents a new minimum thrust control strategy capable of stabilizing a floating wind turbine. The new control strategy explores the freedom of variable generator speed above rated wind speed. A comparison to the traditional constant speed strategy, shows improvements in structural fore-aft oscillations...

  9. Generators of Modern Wind Turbines

    DEFF Research Database (Denmark)

    Chen, Zhe

    2008-01-01

    In this paper, various types of wind generator configurations, including power electronic grid interfaces, drive trains, are described The performance in power systems is briefed. Then the optimization of generator system is presented. Some investigation results are presented and discussed....

  10. Database on wind characteristics - Analyses of wind turbine design loads

    Energy Technology Data Exchange (ETDEWEB)

    Larsen, G.C.; Hansen, K.S.

    2004-06-01

    The main objective of IEA R and D Wind Annex XVII - Database on Wind Characteristics - has been to provide wind energy planners, designers and researchers, as well as the international wind engineering community in general, with a source of actual wind field data (time series and resource data) observed in a wide range of different wind climates and terrain types. Connected to an extension of the initial Annex period, the scope for the continuation was widened to include also support to the international wind turbine standardisation efforts.. The project partners are Sweden, Norway, U.S.A., The Netherlands and Denmark, with Denmark as the Operating Agent. The reporting of the continuation of Annex XVII falls in two separate parts. Part one accounts in details for the available data in the established database bank, and part two describes various data analyses performed with the overall purpose of improving the design load cases with relevance for to wind turbine structures. The present report constitutes the second part of the Annex XVII reporting. Both fatigue and extreme load aspects are dealt with, however, with the main emphasis on the latter. The work has been supported by The Ministry of Environment and Energy, Danish Energy Agency, The Netherlands Agency for Energy and the Environment (NOVEM), The Norwegian Water Resources and Energy Administration (NVE), The Swedish National Energy Administration (STEM) and The Government of the United States of America. (au)

  11. Integrating Structural Health Management with Contingency Control for Wind Turbines

    Directory of Open Access Journals (Sweden)

    Kai Goebel

    2013-01-01

    Full Text Available Maximizing turbine up-time and reducing maintenance costs are key technology drivers for wind turbine operators. Components within wind turbines are subject to considerable stresses due to unpredictable environmental conditions resulting from rapidly changing local dynamics. In that context, systems health management has the aim to assess the state-of-health of components within a wind turbine, to estimate remaining life, and to aid in autonomous decision-making to minimize damage to the turbine. Advanced contingency control is one way to enable autonomous decision-making by providing the mechanism to enable safe and efficient turbine operation. The work reported herein explores the integration of condition monitoring of wind turbine blades with contingency control to balance the trade-offs between maintaining system health and energy capture. Results are demonstrated using a high fidelity simulator of a utility-scale wind turbine.

  12. Wind flow through shrouded wind turbines

    Science.gov (United States)

    2017-03-01

    velocity and model angle were varied . Additionally, static wall pressures and cross section flow were studied with the addition of a screen. The pressure...the geometry of a wind lens or flange on the shroud and a gradually diverging shape, proved to accelerate the flow through the duct. 14. SUBJECT...Tunnel velocity and model angle were varied . Additionally, static wall pressures and cross section flow were studied with the addition of a screen. The

  13. Control of variable speed pitch-regulated wind turbines in strong wind conditions using a combined feedforward and feedback technique

    DEFF Research Database (Denmark)

    Feng, Ju; Shen, Wen Zhong

    2012-01-01

    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...

  14. Convergence of Extreme Loads for Offshore Wind Turbine Support Structures

    OpenAIRE

    Stewart, Gordon; Lackner, Matthew; Arwade, Sanjay R.; Myers, Andrew T.; Hallowell, Spencer

    2015-01-01

    Extreme loads of wind turbines are historically difficult to predict through simulation due to uncertainty in input conditions as well as in the simulation models. In addition, many long time series must be simulated for the statistics of the peak loads to become stationary. Offshore wind turbines require even more simulation due to the addition of stochastic wave loading. Floating offshore wind turbines, the subject of this paper, experience free-body motion as a result of wind and wave load...

  15. Wind Turbine Development at Montana State University

    Energy Technology Data Exchange (ETDEWEB)

    Cairns, Douglas S. [Montana State Univ., Bozeman, MT (United States). Mechanical and Industrial Engineering Dept.; Riddle, William [Montana State Univ., Bozeman, MT (United States). Mechanical and Industrial Engineering Dept.; Nelson, Jared [Montana State Univ., Bozeman, MT (United States). Mechanical and Industrial Engineering Dept.; Peterson, William [Montana State Univ., Bozeman, MT (United States). Mechanical and Industrial Engineering Dept.

    2015-02-23

    A survey of wind turbine blade manufacturers, repair companies, wind farm operators, and third party investigators has directed the focus of this investigation on several types of flaws commonly found in wind turbine blades: waviness and porosity/voids. Several commercial scale wind turbine blades were inspected for the development of metrics for the identification, analysis and disposition. Analysis of flaw geometries yielded metrics which utilize specific parameters to physically characterize a defect. Data as it relates flaw parameters to frequencies of occurrence have been complied. Basic statistical analysis shows that the frequency of flaw parameters generally follows standard distributions. A testing program was then developed around this flaw data. Results from static testing indicate that there is strong correlation between flaw parameters and mechanical response. Preliminary results from the in-field data collection effort and coupon level testing have established a protocol by which a defect in a blade can be characterized quantifiably. With this data it is possible to develop probabilistic analysis, damage progression models and criticality assessment tools that will enable improved blade design methodology and the development of a risk management framework which describes the probability of failure for blades with defects.

  16. Design of a novel and efficient lantern wind turbine

    Science.gov (United States)

    Ibrahim, M. D.; Wong, L. K.; Anyi, M.; Yunos, Y. S.; Rahman, M. R. A.; Mohta, M. Z.

    2017-04-01

    Wind turbine generates renewable energy when the forces acted on the turbine blades cause the rotation of the generator to produce clean electricity. This paper proposed a novel lantern wind turbine design compared to a conventional design model. Comparison is done based on simulation on coarse and fine meshing with all the results converged. Results showed that the pressure difference on the surface of novel design lantern wind turbine is much higher compared to the conventional wind turbine. Prototype is already manufactured and experimental result would be discussed in a separate future publication

  17. Robust, Gain-Scheduled Control of Wind Turbines

    DEFF Research Database (Denmark)

    Østergaard, Kasper Zinck

    Wind turbines are today large and efficient machines, which are combined into wind farms operating on par with conventional power plants. When looking back, this is significantly different from the status only a few years ago, when wind turbines were sold mainly to private people. This change...... in turbine owners has resulted in a new focus on operational reliability instead of turbine size. This research deals with investigating model-based gain-scheduling control of wind turbines by use of linear parameter varying (LPV) methods. The numerical challenges grow quickly with the model size...

  18. Semiconductor Laser Lidar Wind Velocity Sensor for Turbine Control

    DEFF Research Database (Denmark)

    Rodrigo, Peter John; Hu, Qi; Pedersen, Christian

    2014-01-01

    A dual line-of-sight CW lidar that measures both wind speed and direction is presented . The wind lidar employs a semiconductor laser, which allows for inexpensive remote sensors geared towards enhanced control of wind turbines .......A dual line-of-sight CW lidar that measures both wind speed and direction is presented . The wind lidar employs a semiconductor laser, which allows for inexpensive remote sensors geared towards enhanced control of wind turbines ....

  19. Braking System for Wind Turbines

    Science.gov (United States)

    Krysiak, J. E.; Webb, F. E.

    1987-01-01

    Operating turbine stopped smoothly by fail-safe mechanism. Windturbine braking systems improved by system consisting of two large steel-alloy disks mounted on high-speed shaft of gear box, and brakepad assembly mounted on bracket fastened to top of gear box. Lever arms (with brake pads) actuated by spring-powered, pneumatic cylinders connected to these arms. Springs give specific spring-loading constant and exert predetermined load onto brake pads through lever arms. Pneumatic cylinders actuated positively to compress springs and disengage brake pads from disks. During power failure, brakes automatically lock onto disks, producing highly reliable, fail-safe stops. System doubles as stopping brake and "parking" brake.

  20. System Identification for the Clipper Liberty C96 Wind Turbine

    Science.gov (United States)

    Showers, Daniel

    System identification techniques are powerful tools that help improve modeling capabilities of real world dynamic systems. These techniques are well established and have been successfully used on countless systems in many areas. However, wind turbines provide a unique challenge for system identification because of the difficulty in measuring its primary input: wind. This thesis first motivates the problem by demonstrating the challenges with wind turbine system identification using both simulations and real data. It then suggests techniques toward successfully identifying a dynamic wind turbine model including the notion of an effective wind speed and how it might be measured. Various levels of simulation complexity are explored for insights into calculating an effective wind speed. In addition, measurements taken from the University of Minnesota's Clipper Liberty C96 research wind turbine are used for a preliminary investigation into the effective wind speed calculation and system identification of a real world wind turbine.

  1. Weather response to a large wind turbine array

    Directory of Open Access Journals (Sweden)

    D. B. Barrie

    2010-01-01

    Full Text Available Electrical generation by wind turbines is increasing rapidly, and has been projected to satisfy 15% of world electric demand by 2030. The extensive installation of wind farms would alter surface roughness and significantly impact the atmospheric circulation due to the additional surface roughness forcing. This forcing could be changed deliberately by adjusting the attitude of the turbine blades with respect to the wind, which would enable the "management" of a large array of wind turbines. Using a General Circulation Model (GCM, we represent a continent-scale wind farm as a distributed array of surface roughness elements. Here we show that initial disturbances caused by a step change in roughness grow within four and a half days such that the flow is altered at synoptic scales. The growth rate of the induced perturbations is largest in regions of high atmospheric instability. For a roughness change imposed over North America, the induced perturbations involve substantial changes in the track and development of cyclones over the North Atlantic, and the magnitude of the perturbations rises above the level of forecast uncertainty.

  2. Interactive 3D geodesign tool for multidisciplinary wind turbine planning.

    Science.gov (United States)

    Rafiee, Azarakhsh; Van der Male, Pim; Dias, Eduardo; Scholten, Henk

    2018-01-01

    Wind turbine site planning is a multidisciplinary task comprising of several stakeholder groups from different domains and with different priorities. An information system capable of integrating the knowledge on the multiple aspects of a wind turbine plays a crucial role on providing a common picture to the involved groups. In this study, we have developed an interactive and intuitive 3D system (Falcon) for planning wind turbine locations. This system supports iterative design loops (wind turbine configurations), based on the emerging field of geodesign. The integration of GIS, game engine and the analytical models has resulted in an interactive platform with real-time feedback on the multiple wind turbine aspects which performs efficiently for different use cases and different environmental settings. The implementation of tiling techniques and open standard web services support flexible and on-the-fly loading and querying of different (massive) geospatial elements from different resources. This boosts data accessibility and interoperability that are of high importance in a multidisciplinary process. The incorporation of the analytical models in Falcon makes this system independent from external tools for different environmental impacts estimations and results in a unified platform for performing different environmental analysis in every stage of the scenario design. Game engine techniques, such as collision detection, are applied in Falcon for the real-time implementation of different environmental models (e.g. noise and visibility). The interactivity and real-time performance of Falcon in any location in the whole country assist the stakeholders in the seamless exploration of various scenarios and their resulting environmental effects and provides a scope for an interwoven discussion process. The flexible architecture of the system enables the effortless application of Falcon in other countries, conditional to input data availability. The embedded open web

  3. Effects of normal and extreme turbulence spectral parameters on wind turbine loads

    DEFF Research Database (Denmark)

    Dimitrov, Nikolay Krasimirov; Natarajan, Anand; Mann, Jakob

    2017-01-01

    Loads simulations as performed to obtain design loads on wind turbines, requires wind turbulence as an input, characterized by parameters associated with the turbulence length scale, dissipation and anisotropy. The effect of variation in these turbulence spectral parameters on the magnitude...... the recommended values in the IEC 61400-1 Ed.3 that is used for wind turbine design. The present paper investigates the impact of Mann turbulence model parameter variations on the design loads envelope for 5 MW and 10 MW reference wind turbines. Specific focus is made on the blade root loads, tower top moments...

  4. Optimized Control Strategy For Over Loaded Offshore Wind Turbines

    DEFF Research Database (Denmark)

    Odgaard, Peter Fogh; Knudsen, Torben; Wisniewski, Rafal

    2015-01-01

    Abstract Optimized control strategy for overloaded offshore wind turbines Introduction Operation and maintenance cost are an important part of cost of energy especially for offshore wind farms. Typically unplanned service is called for due to detection off excessive loads on components, e.......g., the tower. In the process of decreasing the cost of energy of wind turbines it is relevant to continue some level of production while awaiting service and repair of the offshore wind turbine. This is typically done operating the wind turbine in a power de-rated operation mode, assuming that lower power...... generation results in lower loads on the wind turbine, which enables continued production until next service. Approach Recent results in Model Predictive Control (MPC) applied to wind turbines show a potential for presenting possible controller tunings which weighs multiple conflicting objectives...

  5. Power Curve of the AWEC-60 wind turbine

    International Nuclear Information System (INIS)

    Avia, F.

    1992-01-01

    The experimental wind turbine AWEC-60 was developed to evaluate the possibilities of the Large Wind turbines, from the technical and economical point of view. The project was developed by a spanish-german group, integrated by Union Fenosa, Asinel, M.A.N. Neue Technologie and the Instituto de Energias Renovables from CIEMAT, starting the operation during the year 1990. In this paper, the obtention of the wind turbine power curve is presented, which has been obtained in agreement with the Recommended Practices for Wind Turbine Testing and Evaluation from the Executive Committee for the Research and Development on Wind Energy, of the International Energy Agency (AIE). Using the functioning data of the wind turbine correspondig to the first quarter of the year 1991, the power curves have been obtained, and the results have been compared with the curves measured in other similar Large wind turbines. (Author) 7 refs

  6. Enhanced wind turbine noise prediction tool SILANT

    International Nuclear Information System (INIS)

    Boorsma, K.; Schepers, J.G.

    2012-02-01

    Wind turbine noise often is quantified in terms of time averaged overall sound power levels, whilst annoyance due to noise level fluctuations in mid- to high-range frequencies ('swish') are not taken into account. Recent experimental research on wind turbine noise has revealed the major causes of the swishing noise to be due to the directivity of the noise sources and convective amplification effects of the moving turbine blades. The findings have been incorporated in the noise prediction tool SILANT which in addition to sound power levels gives sound pressure level predictions for specified observer positions. The noise sources that are taken into account are trailing edge, inflow and tip noise, using the models of Brooks, Pope and Marcolini (BPM) and Amiet and Lowson. The blade is divided into a number of independent elements for which effective inflow velocity and angle of attack information is a necessary input. A distinction is made between the various profiles along the blade span by including their boundary layer displacement thicknesses at the trailing edge in a profile database. The propagation model includes directivity, convective amplification, Doppler shift and atmospheric absorption. The effect of the retarded time is taken into account individually for the separate elements along the blade span using the time dependent rotor azimuth position. A simple empirical model is applied to quantify meteorological effects influencing refraction and ground effects. Prediction results are compared to SIROCCO project measurements from microphones positioned in a circle around a turbine. The high spatial and temporal resolution of the SILANT simulations gives new insights in the variation of wind turbine inflow and trailing edge noise as a function of observer position, rotor azimuth angle and frequency band. The influence of directivity is illustrated for the dominant noise sources.

  7. Learning in wind turbine development

    NARCIS (Netherlands)

    Kamp, Linda Manon

    2002-01-01

    Both the Netherlands and Denmark started to develop wind energy in the 1970s. Reasons were the oil crisis and the Club of Rome report, which warned of imminent shortages of traditional energy sources like oil and gas. Both countries started this development around 1975 and their governments gave

  8. Wind turbine reliability database update.

    Energy Technology Data Exchange (ETDEWEB)

    Peters, Valerie A.; Hill, Roger Ray; Stinebaugh, Jennifer A.; Veers, Paul S.

    2009-03-01

    This report documents the status of the Sandia National Laboratories' Wind Plant Reliability Database. Included in this report are updates on the form and contents of the Database, which stems from a fivestep process of data partnerships, data definition and transfer, data formatting and normalization, analysis, and reporting. Selected observations are also reported.

  9. Wind turbines in your environment? Wind turbines and energy context

    International Nuclear Information System (INIS)

    2002-02-01

    Renewable energy sources allow to anticipate the depletion of fossil energy reserves and to limit the use of fissile resources. Moreover, their use avoids the emission of enormous amounts of pollutants and greenhouse gases in the atmosphere. This document presents the French energy context (national resources, electricity production and uses); the international political commitments (Kyoto protocol); the position of nuclear power in France and the development of renewable energy sources; and the evolution of the share of wind power with respect to other energy sources in France, in Europe and in the rest of the world. (J.S.)

  10. Final Report - Certifying the Performance of Small Wind Turbines

    Energy Technology Data Exchange (ETDEWEB)

    Sherwood, Larry [Small Wind Certification Council, Clifton Park, NY (United States)

    2015-08-28

    The Small Wind Certification Council (SWCC) created a successful accredited certification program for small and medium wind turbines using the funding from this grant. SWCC certifies small turbines (200 square meters of swept area or less) to the American Wind Energy Association (AWEA) Small Wind Turbine Performance and Safety Standard (AWEA Standard 9.1 – 2009). SWCC also certifies medium wind turbines to the International Electrical Commission (IEC) Power Performance Standard (IEC 61400-12-1) and Acoustic Performance Standard (IEC 61400-11).

  11. Additive Manufacturing of Wind Turbine Molds

    Energy Technology Data Exchange (ETDEWEB)

    Post, Brian [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Richardson, Bradley [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Lloyd, Peter [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Love, Lonnie [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Nolet, Stephen [TPI Composites, Scottsdale, AZ (United States); Hannan, James [TPI Composites, Scottsdale, AZ (United States)

    2017-07-01

    The objective of this project was to explore the utility of Big Area Additive Manufacturing (BAAM) for low cost manufacturing of wind turbine molds. Engineers at Oak Ridge National Laboratory (ORNL) and TPI Composites (TPI) collaborated to design and manufacture a printed mold that can be used for resin infusion of wind turbine components. Specific focus was on required material properties (operating temperatures and pressures, coefficient of thermal expansion (CTE), thermal conductivity), surface finish (accuracy and coatings) and system integration (integrated vacuum ports, and heating element). The project began with a simple proof of principle components, targeting surface coatings and material properties for printing a small section (approximately 4’ x 4’ x 2’) of a mold. Next, the second phase scaled up and integrated with the objective of capturing all of the necessary components (integrated heating to accelerate cure time, and vacuum, sealing) for resin infusion on a mold of significant size (8’ x 20’ x 6’).

  12. Damping of wind turbine tower vibrations

    DEFF Research Database (Denmark)

    Brodersen, Mark Laier; Pedersen, Mikkel Melters

    Damping of wind turbine vibrations by supplemental dampers is a key ingredient for the continuous use of monopiles as support for offshore wind turbines. The present thesis consists of an extended summary with four parts and appended papers [P1-P4] concerning novel strategies for damping of tower...... in a stroke amplifying brace, which amplifies the displacement across the damper and thus reduces the desired level of damper force. For optimal damping of the two lowest tower modes, a novel toggle-brace concept for amplifying the bending deformation of the tower is presented. Numerical examples illustrate...... damper with IFFis validated by a series of real time hybrid simulations (RTHS). The experimental results illustrate the ability of the hybrid damper concept to increase damper stroke or attainable damping. The results also show that the actuator signal is quitesensitive to drift due an offset...

  13. Development of Superconducting Wind Turbine Generators

    DEFF Research Database (Denmark)

    Jensen, Bogi Bech; Mijatovic, Nenad; Abrahamsen, Asger Bech

    2012-01-01

    speeds, because high magnetic fields can be produced by coils with very little loss. Three different superconducting wind turbine generator topologies have been proposed by three different companies. One is based on low temperature superconductors (LTS); one is based on high temperature superconductors......In this paper the commercial activities in the field of superconducting machines, particularly superconducting wind turbine generators, are reviewed and presented. Superconducting generators have the potential to provide a compact and light weight drive train at high torques and slow rotational...... (HTS); and one is a fully superconducting generator based on MgB2. It is concluded that there is large commercial interest in superconducting machines, with an increasing patenting activity. Such generators are however not without their challenges. The superconductors have to be cooled down...

  14. Development of superconducting wind turbine generators

    DEFF Research Database (Denmark)

    Jensen, Bogi Bech; Mijatovic, Nenad; Abrahamsen, Asger Bech

    2013-01-01

    speeds, because high magnetic fields can be produced by coils with very little loss. Three different superconducting wind turbine generator topologies have been proposed by three different companies. One is based on low temperature superconductors; one is based on high temperature superconductors......In this paper, the commercial activities in the field of superconducting machines, particularly superconducting wind turbine generators, are reviewed and presented. Superconducting generators have the potential to provide a compact and light weight drive train at high torques and slow rotational......; and one is a fully superconducting generator based on MgB2. It is concluded that there is large commercial interest in superconducting machines, with an increasing patenting activity. Such generators are, however, not without their challenges. The superconductors have to be cooled down to somewhere...

  15. Hybrid Optimization for Wind Turbine Thick Airfoils

    Energy Technology Data Exchange (ETDEWEB)

    Grasso, F. [ECN Wind Energy, Petten (Netherlands)

    2012-06-15

    One important element in aerodynamic design of wind turbines is the use of specially tailored airfoils to increase the ratio of energy capture and reduce cost of energy. This work is focused on the design of thick airfoils for wind turbines by using numerical optimization. A hybrid scheme is proposed in which genetic and gradient based algorithms are combined together to improve the accuracy and the reliability of the design. Firstly, the requirements and the constraints for this class of airfoils are described; then, the hybrid approach is presented. The final part of this work is dedicated to illustrate a numerical example regarding the design of a new thick airfoil. The results are discussed and compared to existing airfoils.

  16. Aeroelastic optimization of MW wind turbines

    Energy Technology Data Exchange (ETDEWEB)

    Hartvig Hansen, M.; Zahle, F.

    2011-12-15

    This report contains the results from the Energy Development and Demonstration Project ''Aeroelastic Optimization of MW wind turbine'' (AeroOpt). The project has had the following five Work Packages: 1. Geometric non-linear, anisotropic beam element for HAWC2. 2. Closed-loop eigenvalue analysis of controlled wind turbines. 3. Resonant wave excitation of lateral tower bending modes. 4. Development of next generation aerodynamic design tools. 5. Advanced design and verification of airfoils. The purposes of these Work Packages are briefly described in the Preface and a summary of the results are given in Section 2. Thereafter, the results from each Work Package are described in eight subsequent chapters. (Author)

  17. Some aspects on wind turbines monitoring. General considerations and loads on horizontal wind turbines

    Energy Technology Data Exchange (ETDEWEB)

    Cuerva, A.

    1996-12-01

    The concept Monitoring applied to the Wind Energy technology is similar to the definition used in other branches of Science or Engineering, this is knowing values of variables which have to do with a mechanic system, in our case a wind turbine. These mentioned parameters may have different relationships to our wind turbine; some of them come from the environment the machine is operating in, others, are a measure of how properly the machine is working, and finally, the rest are an assessment of the ``system`s health`` during its ``life``. In this chapter we will answer questions such as: What do we need to measure? Why is Monitoring mandatory (from the different points of view of people involved in this world)? How can we measure a wind turbine depending on our objectives (Technic, tools, guidance, recommendations, etc)? And finally What can we expect in the near future?. The author wants the reader to keep the idea in mind that Monitoring means the richest and most accurate knowledge on wind turbine`s operation (Its environment, performances of health). This is the first step that allows us to optimize the operation mode of the machine and improve it (design, manufacturing, even the used modeling tools). When there is so much money involved, this fact becomes a must. (Author)

  18. Wind Turbine Generator System Duration Test Report for the Gaia-Wind 11 kW Wind Turbine

    Energy Technology Data Exchange (ETDEWEB)

    Huskey, A.; Bowen, A.; Jager, D.

    2010-09-01

    This test was conducted as part of the U.S. Department of Energy's (DOE) Independent Testing project. This project was established to help reduce the barriers of wind energy expansion by providing independent testing results for small turbines. In total, five turbines are being tested at the National Renewable Energy Laboratory's (NRELs) National Wind Technology Center (NWTC) as a part of this project. Duration testing is one of up to five tests that may be performed on the turbines, including power performance, safety and function, noise, and power quality tests. The results of the testing will provide the manufacturers with reports that may be used for small wind turbine certification. The test equipment includes a Gaia-Wind 11 kW wind turbine mounted on an 18 m monopole tower. Gaia-Wind Ltd. manufactured the turbine in Denmark, although the company is based in Scotland. The system was installed by the NWTC Site Operations group with guidance and assistance from Gaia-Wind.

  19. Wear Analysis of Wind Turbine Gearbox Bearings

    Energy Technology Data Exchange (ETDEWEB)

    Blau, Peter Julian [ORNL; Walker, Larry R [ORNL; Xu, Hanbing [ORNL; Parten, Randy J [ORNL; Qu, Jun [ORNL; Geer, Tom [ORNL

    2010-04-01

    The objective of this effort was to investigate and characterize the nature of surface damage and wear to wind turbine gearbox bearings returned from service in the field. Bearings were supplied for examination by S. Butterfield and J. Johnson of the National Wind Technology Center (NREL), Boulder, Colorado. Studies consisted of visual examination, optical and electron microscopy, dimensional measurements of wear-induced macro-scale and micro-scale features, measurements of macro- and micro-scale hardness, 3D imaging of surface damage, studies of elemental distributions on fracture surfaces, and examinations of polished cross-sections of surfaces under various etched and non-etched conditions.

  20. Active system monitoring applied on wind turbines

    DEFF Research Database (Denmark)

    Niemann, Hans Henrik; Poulsen, Niels Kjølstad; Parbo, Henrik

    2009-01-01

    A concept for active system monitoring (ASM) applied on wind turbines is presented in this paper. The concept is based on an injection of a small periodic auxiliary signal in the system. An investigation of the signature from the auxiliary input in residual (error) signals can then be applied for...... for an online monitoring of central parameters/elements of the system. Statistical tests are applied on the residual signals for obtaining a correct monitoring....

  1. Impact of assimilating met-tower, turbine nacelle anemometer and other intensified wind farm observation systems on 0 - 12h wind energy prediction using the NCAR WRF-RTFDDA model

    Science.gov (United States)

    Liu, Y.; Cheng, W.; Liu, Y. W.; Wiener, G.; Frehlich, R.; Mahoney, W.; Warner, T.; Himelic, J.; Parks, K.; Early, S.

    2010-09-01

    In collaboration with Xcel Energy and Vasaila Inc., the National Center for Atmospheric Research (NCAR) conducts modeling study to evaluate the existing and the enhanced intensive observation systems for wind power nowcasting and short-range forecasting at a northern Colorado wind farm. The NCAR WRF (Weather Research and Forecasting model) based Real-Time Four-Dimensional Data Assimilation (RTFDDA) and forecasting system, which has been employed to support Xcel Energy operational wind forecast, was used in this study. The observational data include ten met-towers, a 915Hz wind profiler, a sodar and a Windcube Doppler lidar, besides the in-farm met-towers and wind speed and power reports from more than 300 of wind turbines. The WRF-RTFDDA 4-dimensioanl data assimilation algorithm allows to spread and propagate observation information in the WRF model space (x, y, z and time) with weighting functions built according to the observation location and time. The WRF-RTFDDA was set up to run with four nested domains with grid increments of 30, 10, 3.333 and 1.111km respectively. The standard and diverse non-conventional observations are assimilated on coarse grid domains along with the special wind farm observations. In this study, we investigate a) spread of surface observations in PBL according to PBL depth and regimes, b) optimization of horizontal influence radii and steep-terrain adjustment, and c) impact of different observation platforms and data types on 0 - 12 h wind prediction . It is found that PBL mixing and thermodynamic structures are greatly influenced by the PBL parameterization formulation. The range of the data assimilation effect on forecasts relies on weather and PBL regimes. In most cases, assimilation of in-farm and near-farm observations improves up to 12-hour wind power prediction and assimilation of in-farm data can significantly improves 0 - 6 hour forecasts.

  2. Siting guidelines for utility application of wind turbines. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Pennell, W.T.

    1983-01-01

    Utility-oriented guidelines are described for identifying viable sites for wind turbines. Topics and procedures are also discussed that are important in carrying out a wind turbine siting program. These topics include: a description of the Department of Energy wind resource atlases; procedures for predicting wind turbine performance at potential sites; methods for analyzing wind turbine economics; procedures for estimating installation and maintenance costs; methods for anlayzing the distribution of wind resources over an area; and instrumentation for documenting wind behavior at potential sites. The procedure described is applicable to small and large utilities. Although the procedure was developed as a site-selection tool, it can also be used by a utility who wishes to estimate the potential for wind turbine penetration into its future generation mix.

  3. Model-Based Control of a Ballast-Stabilized Floating Wind Turbine Exposed to Wind and Waves

    DEFF Research Database (Denmark)

    Christiansen, Søren

    2013-01-01

    wind turbine, for water depths beyond 50 meters where winds are stronger and less turbulent. A floating wind turbine is subject to not only aerodynamics and wind induced loads, but also to hy-drodynamics and wave induced loads. In contrast to a bottom fixed wind turbine, the floating structure....... A time varying control model is presented based on the wind speed and wave frequency. Estimates of the wind speed and wave frequency are used as scheduling variables in a gain scheduled linear quadratic controller to improve the electrical power production while reducing fatigue. To address the problem...... of negative damped fore--aft tower motion, addi-tional control loops are suggested which stabilize the response of the onshore controller and reduce the impact of the wave induced loads. This research is then extended to model predictive control, to further address wave disturbances. In the context of control...

  4. Blade-Pitch Control for Wind Turbine Load Reductions

    DEFF Research Database (Denmark)

    Lio, Alan Wai Hou

    Large wind turbines are subjected to the harmful loads that arise from the spatially uneven and temporally unsteady oncoming wind. Such loads are the known sources of fatigue damage that reduce the turbine operational lifetime, ultimately increasing the cost of wind energy to the end-users. In re...

  5. The benefits of geographical dispersion of offshore wind turbines.

    NARCIS (Netherlands)

    Assen van, Vincent

    2012-01-01

    Summary Wind energy is one of the possible solutions to minimise the greenhouse gas emissions of our electricity production. Therefore, the Dutch government aims to install 6000 MW of wind turbines on the Dutch North Sea. The power output of wind turbine

  6. Wind Turbine Generator System Safety and Function Test Report for the Southwest Windpower H40 Wind Turbine

    Energy Technology Data Exchange (ETDEWEB)

    van Dam, J.; Link, H.; Meadors, M.; Bianchi, J.

    2002-06-01

    The objective of this test was to evaluate the safety and function characteristics of the Whisper H40 wind turbine. The general requirements of wind turbine safety and function tests are defined in the IEC standard WT01. The testing was conducted in accordance with the National Wind Technology Center (NWTC) Quality Assurance System, including the NWTC Certification Team Certification Quality Manual and the NWTC Certification Team General Quality Manual for the Testing of Wind Turbines, as well as subordinate documents. This safety and function test was performed as part of the U.S. Department of Energy's Field Verification Program for small wind turbines.

  7. Assessment of U.S. Manufacturing Capability for Next-Generation Wind Turbine Drivetrains

    Energy Technology Data Exchange (ETDEWEB)

    Cotrell, J. [National Renewable Energy Lab. (NREL), Golden, CO (United States); Stelhy, T. [National Renewable Energy Lab. (NREL), Golden, CO (United States)

    2013-09-01

    Robust U.S. wind turbine manufacturing capabilities and supply chains are important for the United States to reduce the cost of electricity generated from wind turbines. These capabilities and supply chains are also critical to the invention and commercialization of new wind turbine technologies while providing high-quality jobs. The development of advanced drivetrain technologies for windturbine applications is advancing the state of the art for drivetrain design by producing higher capacity and operating reliability than conventional drivetrains. Advanced drivetrain technologies such as medium-speed and direct-drive generators, silicon-carbide (SiC) IGBT-based power electronics, and high torque density speed increasers require different manufacturing and supply chaincapabilities that present both risks and opportunities for U.S. wind turbine manufacturers and the wind industry as a whole. The primary objective of this project is to assess how advanced drivetrain technologies and trends will impact U.S. wind turbine manufacturing and its supply chains. The U.S. Department of Energy and other industry participants will use the information from this study toidentify domestic manufacturing gaps, barriers, and opportunities for developing U.S. wind turbine manufacturing capabilities and supply chains for next-generation drivetrain technologies. This report also includes recommendations for prioritizing technology areas for possible investments by public, private, or nonprofit entities that will reduce the cost of wind-generated electricity. Suchinvestments foster opportunities to invent and commercialize new wind turbine technologies, and provide high-quality jobs in the United States.

  8. Baseline Design of a Hurricane-Resilient Wind Turbine (Poster)

    Energy Technology Data Exchange (ETDEWEB)

    Damiani, R.; Robertson, A.; Schreck, S.; Maples, B.; Anderson, M.; Finucane, Z.; Raina, A.

    2014-10-01

    Under U.S. Department of Energy-sponsored research FOA 415, the National Renewable Energy Laboratory led a team of research groups to produce a complete design of a large wind turbine system to be deployable in the western Gulf of Mexico region. As such, the turbine and its support structure would be subjected to hurricane-loading conditions. Among the goals of this research was the exploration of advanced and innovative configurations that would help decrease the levelized cost of energy (LCOE) of the design, and the expansion of the basic IEC design load cases (DLCs) to include hurricane environmental conditions. The wind turbine chosen was a three-bladed, downwind, direct-drive, 10-MW rated machine. The rotor blade was optimized based on an IEC load suite analysis. The drivetrain and nacelle components were scaled up from a smaller sized turbine using industry best practices. The tubular steel tower was sized using ultimate load values derived from the rotor optimization analysis. The substructure is an innovative battered and raked jacket structure. The innovative turbine has also been modeled within an aero-servo-hydro-elastic tool, and future papers will discuss results of the dynamic response analysis for select DLCs. Although multiple design iterations could not be performed because of limited resources in this study, and are left to future research, the obtained data will offer a good indication of the expected LCOE for large offshore wind turbines to be deployed in subtropical U.S. waters, and the impact design innovations can have on this value.

  9. Study of wind turbine foundations in cold climates

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2012-11-01

    This report provides an overview of the processes at work in soil in cold climates and their effect on wind turbine foundations. Havsnaes wind farm consists of 48 turbines located in Jaemtland county in central Sweden. Havsnaes has provided an appropriate research environment to investigate the engineering challenges related to the design and construction of wind turbine foundations in sub-arctic conditions and the experienced gained from this project informs this report.

  10. Wind turbine fault detection and fault tolerant control

    DEFF Research Database (Denmark)

    Odgaard, Peter Fogh; Johnson, Kathryn

    2013-01-01

    In this updated edition of a previous wind turbine fault detection and fault tolerant control challenge, we present a more sophisticated wind turbine model and updated fault scenarios to enhance the realism of the challenge and therefore the value of the solutions. This paper describes...... the challenge model and the requirements for challenge participants. In addition, it motivates many of the faults by citing publications that give field data from wind turbine control tests....

  11. Mapping Ontario’s Wind Turbines: Challenges and Limitations

    Directory of Open Access Journals (Sweden)

    Tanya Christidis

    2013-11-01

    Full Text Available Despite rapid and vast development of wind turbines across the Canadian province of Ontario, there is no map available indicating the location of each wind turbine. A map of this nature is crucial for health and environmental risk research and has many applications in other fields. Research examining health and wind turbines is limited by the available maps showing the nearest community to a wind farm as opposed to each unique wind turbine. Data from provincial-level organizations, developers, and municipalities were collected using government development approval documents, planning documents, and data given directly from municipalities and developers. Wind turbines were mapped using Google Earth, coordinate lists, shapefiles, and translating data from other maps. In total, 1,420 wind turbines were mapped from 56 wind farms. The limitations of each data source and mapping method are discussed. There are numerous challenges in creating a map of this nature, for example incorrect inclusion of wind farms and inaccuracies in wind turbine locations. The resultant map is the first of its kind to be discussed in the literature, can be used for a variety of health and environmental risk studies to assess dose-response, wind turbine density, visibility, and to create sound and vibration models.

  12. Superconductivity for Large Scale Wind Turbines

    Energy Technology Data Exchange (ETDEWEB)

    R. Fair; W. Stautner; M. Douglass; R. Rajput-Ghoshal; M. Moscinski; P. Riley; D. Wagner; J. Kim; S. Hou; F. Lopez; K. Haran; J. Bray; T. Laskaris; J. Rochford; R. Duckworth

    2012-10-12

    A conceptual design has been completed for a 10MW superconducting direct drive wind turbine generator employing low temperature superconductors for the field winding. Key technology building blocks from the GE Wind and GE Healthcare businesses have been transferred across to the design of this concept machine. Wherever possible, conventional technology and production techniques have been used in order to support the case for commercialization of such a machine. Appendices A and B provide further details of the layout of the machine and the complete specification table for the concept design. Phase 1 of the program has allowed us to understand the trade-offs between the various sub-systems of such a generator and its integration with a wind turbine. A Failure Modes and Effects Analysis (FMEA) and a Technology Readiness Level (TRL) analysis have been completed resulting in the identification of high risk components within the design. The design has been analyzed from a commercial and economic point of view and Cost of Energy (COE) calculations have been carried out with the potential to reduce COE by up to 18% when compared with a permanent magnet direct drive 5MW baseline machine, resulting in a potential COE of 0.075 $/kWh. Finally, a top-level commercialization plan has been proposed to enable this technology to be transitioned to full volume production. The main body of this report will present the design processes employed and the main findings and conclusions.

  13. European wind turbine testing procedure developments. Task 1: Measurement method to verify wind turbine performance characteristics

    DEFF Research Database (Denmark)

    Hunter, R.; Friis Pedersen, Troels; Dunbabin, P.

    2001-01-01

    There is currently significant standardisation work ongoing in the context of wind farm energy yield warranty assessment and wind turbine power performance testing. A standards maintenance team is revising the current IEC (EN) 61400-12 Ed 1 standard forwind turbine power performance testing...... standard. The work was wide ranging and addressed 'grey' areas of knowledge, regarding existing methodologies or to carry out basic research in support offundamentally new procedures. The work has given rise to recommendations in all areas of the work, including site calibration procedures, nacelle...

  14. Transient and dynamic control of a variable speed wind turbine with synchronous generator

    Energy Technology Data Exchange (ETDEWEB)

    Jauch, Clemens [Riso National Laboratory, Wind Energy Department, PO Box 49, DK 4000 Roskilde, (Denmark)

    2007-02-14

    In this article, a controller for dynamic and transient control of a variable speed wind turbine with a full-scale converter-connected high-speed synchronous generator is presented. First, the phenomenon of drive train oscillations in wind turbines with full-scale converter-connected generators is discussed. Based on this discussion, a controller is presented that dampens these oscillations without impacting on the power that the wind turbine injects into the grid. Since wind turbines are increasingly demanded to take over power system stabilizing and control tasks, the presented wind turbine design is further enhanced to support the grid in transient grid events. A controller is designed that allows the wind turbine to ride through transient grid faults. Since such faults often cause power system oscillations, another controller is added that enables the turbine to participate in the damping of such oscillations. It is concluded that the controllers presented keep the wind turbine stable under any operating conditions, and that they are capable of adding substantial damping to the power system. (Author).

  15. Detecting and mitigating wind turbine clutter for airspace radar systems.

    Science.gov (United States)

    Wang, Wen-Qin

    2013-01-01

    It is well recognized that a wind turbine has a large radar cross-section (RCS) and, due to the movement of the blades, the wind turbine will generate a Doppler frequency shift. This scattering behavior may cause severe interferences on existing radar systems including static ground-based radars and spaceborne or airborne radars. To resolve this problem, efficient techniques or algorithms should be developed to mitigate the effects of wind farms on radars. Herein, one transponder-based mitigation technique is presented. The transponder is not a new concept, which has been proposed for calibrating high-resolution imaging radars. It modulates the radar signal in a manner that the retransmitted signals can be separated from the scene echoes. As wind farms often occupy only a small area, mitigation processing in the whole radar operation will be redundant and cost inefficient. Hence, this paper uses a transponder to determine whether the radar is impacted by the wind farms. If so, the effects of wind farms are then mitigated with subsequent Kalman filtering or plot target extraction algorithms. Taking airborne synthetic aperture radar (SAR) and pulse Doppler radar as the examples, this paper provides the corresponding system configuration and processing algorithms. The effectiveness of the mitigation technique is validated by numerical simulation results.

  16. Frequency weighted model predictive control of wind turbine

    DEFF Research Database (Denmark)

    Klauco, Martin; Poulsen, Niels Kjølstad; Mirzaei, Mahmood

    2013-01-01

    This work is focused on applying frequency weighted model predictive control (FMPC) on three blade horizontal axis wind turbine (HAWT). A wind turbine is a very complex, non-linear system influenced by a stochastic wind speed variation. The reduced dynamics considered in this work...... are the rotational degree of freedom of the rotor and the tower for-aft movement. The MPC design is based on a receding horizon policy and a linearised model of the wind turbine. Due to the change of dynamics according to wind speed, several linearisation points must be considered and the control design adjusted...... accordingly. In practice is very hard to measure the effective wind speed, this quantity will be estimated using measurements from the turbine itself. For this purpose stationary predictive Kalman filter has been used. Stochastic simulations of the wind turbine behaviour with applied frequency weighted model...

  17. Fatigue-Damage Estimation and Control for Wind Turbines

    DEFF Research Database (Denmark)

    Barradas Berglind, Jose de Jesus

    How can fatigue-damage for control of wind turbines be represented? Fatigue-damage is indeed a crucial factor in structures such as wind turbines that are exposed to turbulent and rapidly changing wind flow conditions. This is relevant both in their design stage and during the control......, the inclusion of fatigue-damage within feedback control loops is of special interest. Four strategies in total are proposed in this work: three for the wind turbine level and one for the wind farm level. On one hand, the three strategies in the turbine level are based on hysteresis operators and strive......-damage estimation in wind turbine components, to the mixed objective operation of wind energy conversion systems, and to the synthesis of control strategies that include hysteresis operators....

  18. 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.

  19. Wind turbine noise propagation modelling: An unsteady approach

    DEFF Research Database (Denmark)

    Barlas, Emre; Zhu, Wei Jun; Shen, Wen Zhong

    2016-01-01

    Wind turbine sound generation and propagation phenomena are inherently time dependent, hence tools that incorporate the dynamic nature of these two issues are needed for accurate modelling. In this paper, we investigate the sound propagation from a wind turbine by considering the effects of unste......Wind turbine sound generation and propagation phenomena are inherently time dependent, hence tools that incorporate the dynamic nature of these two issues are needed for accurate modelling. In this paper, we investigate the sound propagation from a wind turbine by considering the effects...

  20. Fault tolerant control of wind turbines using unknown input observers

    DEFF Research Database (Denmark)

    Odgaard, Peter Fogh; Stoustrup, Jakob

    2012-01-01

    This paper presents a scheme for accommodating faults in the rotor and generator speed sensors in a wind turbine. These measured values are important both for the wind turbine controller as well as the supervisory control of the wind turbine. The scheme is based on unknown input observers, which...... are also used to detect and isolate these faults. The scheme is tested on a known benchmark for FDI and FTC of wind turbines. Tests on this benchmark model show a clear potential of the proposed scheme....

  1. Description and evaluation of foreign wind turbine technology

    International Nuclear Information System (INIS)

    1995-06-01

    It is stated that sales of Danish-manufactured wind turbines abroad are decreasing due to an increase in production, marketing and technology research in other countries. The aim was to give an account of this international development which could form the basis for the future strategies of the Danish Wind turbine industry. The study is based on a survey of relevant literature, interviews with experts on the subject and the collection of the latest data. The survey is limited to wind turbines with a larger capacity than 50 kW. Recommendations are given as to how to conserve and develop the market for Danish wind turbines. (AB) 17 refs

  2. A Method for Modeling of Floating Vertical Axis Wind Turbine

    DEFF Research Database (Denmark)

    Wang, Kai; Hansen, Martin Otto Laver; Moan, Torgeir

    2013-01-01

    It is of interest to investigate the potential advantages of floating vertical axis wind turbine (FVAWT) due to its economical installation and maintenance. A novel 5MW vertical axis wind turbine concept with a Darrieus rotor mounted on a semi-submersible support structure is proposed in this paper....... In order to assess the technical and economic feasibility of this novel concept, a comprehensive simulation tool for modeling of the floating vertical axis wind turbine is needed. This work presents the development of a coupled method for modeling of the dynamics of a floating vertical axis wind turbine...

  3. Backup Mechanical Brake System of the Wind Turbine

    Science.gov (United States)

    Sirotkin, E. A.; Solomin, E. V.; Gandzha, S. A.; Kirpichnikova, I. M.

    2018-01-01

    Paper clarifies the necessity of the emergency mechanical brake systems usage for wind turbines. We made a deep analysis of the wind turbine braking methods available on the market, identifying their strengths and weaknesses. The electromechanical braking appeared the most technically reasonable and economically attractive. We described the developed combined electromechanical brake system for vertical axis wind turbine driven from electric drive with variable torque enough to brake over the turbine even on the storm wind speed up to 45 m/s. The progress was made due to the development of specific kinematic brake system diagram and intelligent control system managed by special operation algorithm.

  4. Some aspects on wind turbines monitoring. General considerations and loads on horizontal wind turbines

    International Nuclear Information System (INIS)

    Cuerva, A.

    1996-01-01

    The concept Monitoring applied to the Wind Energy technology is similar to the definition used in other branches of Science or Engineering, this is knowing values of variables which have to do with a mechanic system, in our case a wind turbine. These mentioned parameters may have different relationships to our wind turbine; some of them come from the environment the machine is operating in, others, are a measure of how properly the machine is working, and finally, the rest are an assessment of the systems health during its life. In this chapter we will answer questions such as: What do we need to measure? Why is Monitoring mandatory (from the different points of view of people involved in this world)? How can we measure a wind turbine depending on our objectives (Technic, tools, guidance, recommendations, etc.)? And finally What can we expect in the near future? The author wants the reader to keep the idea in mind that Monitoring means the richest and most accurate knowledge on wind turbine's operation (Its environment, performances or health). This is the first step that allows us to optimize the operation mode of the machine and improve it (design, manufacturing, even the used modeling tools). When there is so much money involved, this fact becomes a must. (Author)

  5. High resolution wind turbine wake measurements with a scanning lidar

    Science.gov (United States)

    Herges, T. G.; Maniaci, D. C.; Naughton, B. T.; Mikkelsen, T.; Sjöholm, M.

    2017-05-01

    High-resolution lidar wake measurements are part of an ongoing field campaign being conducted at the Scaled Wind Farm Technology facility by Sandia National Laboratories and the National Renewable Energy Laboratory using a customized scanning lidar from the Technical University of Denmark. One of the primary objectives is to collect experimental data to improve the predictive capability of wind plant computational models to represent the response of the turbine wake to varying inflow conditions and turbine operating states. The present work summarizes the experimental setup and illustrates several wake measurement example cases. The cases focus on demonstrating the impact of the atmospheric conditions on the wake shape and position, and exhibit a sample of the data that has been made public through the Department of Energy Atmosphere to Electrons Data Archive and Portal.

  6. Sanitary impacts generated by wind turbines. situation of the wind sector. Proposition for the implementation of the setting-up procedure; Impacts sanitaires du bruit genere par les eoliennes. Etat des lieux de la filiere eolienne. Propositions pour la mise en oeuvre de la procedure d'implantation

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2008-07-01

    The National Academy of Medicine has evaluated the effects on health of wind turbines. This report recommends that the wind turbine construction is at a minimal distance of 1500 m for wind turbines having a power superior to 2.5 MW. The French agency of sanitary safety of environment and work (A.F.S.S.E.T.) is in charge by the Ministry of Health and Environment to evaluate the relevance of this distance recommendation. The work group recommends the implementation of a specifications text of the environmental impact study as well as a compulsory administrative check of the study. It is more particularly a question of: Defining a perimeter of study: indicate all the zones susceptible to be concerned by the noise of wind turbines, even those which are not inhabited; calculating the durations of impact of concerned zones, according to the predictable weather conditions over the year; indicating the measures taken by the developer of the wind farm in case of overtaking of the authorized emergence; the impact studies of the other projects have to take into account a possible incidence in the zones of impact of the wind farm; a cartography of the zones of impact of a wind site must be available in town hall. A particular attention must be attached to the duration and to the representativeness of the study of the existing situation. The method of appreciation of the sound level impact on the environment must be improved, what passes by a deepening of the knowledge in criterion of embarrassment due to the noise, of existence of threshold, spectral validity, validity according to the exposure time. The search for the simplicity in statutory subject should lead to engage efforts of clarification as regards the nuisances criteria. (N.C.)

  7. Wind turbine wake in atmospheric turbulence

    Energy Technology Data Exchange (ETDEWEB)

    Rethore, P.-E.

    2009-10-15

    This thesis describes the different steps needed to design a steady-state computational fluid dynamics (CFD) wind farm wake model. The ultimate goal of the project was to design a tool that could analyze and extrapolate systematically wind farm measurements to generate wind maps in order to calibrate faster and simpler engineering wind farm wake models. The most attractive solution was the actuator disc method with the steady state k-epsilon turbulence model. The first step to design such a tool is the treatment of the forces. This thesis presents a computationally inexpensive method to apply discrete body forces into the finite-volume flow solver with collocated variable treatment (EllipSys), which avoids the pressure-velocity decoupling issue. The second step is to distribute the body forces in the computational domain accordingly to rotor loading. This thesis presents a generic flexible method that associates any kind of shapes with the computational domain discretization. The special case of the actuator disc performs remarkably well in comparison with Conway's heavily loaded actuator disc analytical solution and a CFD full rotor computation, even with a coarse discretization. The third step is to model the atmospheric turbulence. The standard k-epsilon model is found to be unable to model at the same time the atmospheric turbulence and the actuator disc wake and performs badly in comparison with single wind turbine wake measurements. A comparison with a Large Eddy Simulation (LES) shows that the problem mainly comes from the assumptions of the eddy-viscosity concept, which are deeply invalidated in the wind turbine wake region. Different models that intent to correct the k-epsilon model's issues are investigated, of which none of them is found to be adequate. The mixing of the wake in the atmosphere is a deeply non-local phenomenon that is not handled correctly by an eddy-viscosity model such as k-epsilon. (author)

  8. Wind Turbine Power Curve Design for Optimal Power Generation in Wind Farms Considering Wake Effect

    DEFF Research Database (Denmark)

    Tian, Jie; Zhou, Dao; Su, Chi

    2017-01-01

    In modern wind farms, maximum power point tracking (MPPT) is widely implemented. Using the MPPT method, each individual wind turbine is controlled by its pitch angle and tip speed ratio to generate the maximum active power. In a wind farm, the upstream wind turbine may cause power loss to its...... downstream wind turbines due to the wake effect. According to the wake model, downstream power loss is also determined by the pitch angle and tip speed ratio of the upstream wind turbine. By optimizing the pitch angle and tip speed ratio of each wind turbine, the total active power of the wind farm can...... be increased. In this paper, the optimal pitch angle and tip speed ratio are selected for each wind turbine by the exhausted search. Considering the estimation error of the wake model, a solution to implement the optimized pitch angle and tip speed ratio is proposed, which is to generate the optimal control...

  9. Compare. An analysis of jurisprudence of the Dutch Real Estate Appraisal in relation with the vicinity of wind turbines

    International Nuclear Information System (INIS)

    Berenschot, J.H.M.

    2005-11-01

    The central question in this report concerns the impact of recent judgements with regard to the devaluation of houses as a result of wind turbines in the vicinity of those houses. More specific: does the installation of wind turbines near houses effect the so-called Real Estate Appraisal tax for those houses. From four cases it appears that three aspects are important: noise pollution, cast shadow hindrance and visual hindrance, caused by wind turbines [nl

  10. Research in Aeroelasticity EFP-2006[Wind turbines

    Energy Technology Data Exchange (ETDEWEB)

    Bak, C.

    2007-07-15

    This report contains the results from the Energy Research Project 'Program for Research in Applied Aeroelasticity, EFP-2006' covering the period from 1. April 2006 to 31. March 2007. A summary of the main results from the project is given in the following. The aerodynamics for rotors incl. spinner and winglets were clarified and the needed premises for an optimal rotor were explained. Also, the influence of viscous effects on rotor blades was investigated and the results indicated a range of optimum tip speed ratios. The use of winglets for wind turbine rotor was investigated and it was found that they can be used successfully, but that downwind and short winglets are most efficient. Investigating a strategy for reduction of loads and vibrations at extreme wind speeds showed that there are considerably uncertainties in the numerical models and that the main concluding remark is that measurements on a real blade or a real turbine are needed to further conclude the investigation. In the study of flutter and other torsional vibrations of blades at large deflections, modeling and analysis of the dynamics of a hydraulic pitch system for a 5 MW wind turbine was carried out. It was shown that the compressibility of the hydraulic oil introduced a dynamic mode in the pitch bearing degree of freedom. Also, investigating flutter for blades at large deflections showed that the flutter limit for a 5MW blade was moved significantly compared to blades without large deflections. The influence of modeling nacelle components was investigated by developing a generalized method to interface dynamic systems to the aeroelastic program HAWC2 and by exemplify by modeling the nacelle of an aeroelastic wind turbine model in a more detailed way by including a single planet stage of a gearbox. This simplified gearbox model captures in essence the splitting of the driving torque from the rotor shaft to the frame of the nacelle and to the generator. Investigating the influence of wind

  11. Effects of gain-scheduling methods in a classical wind turbine controller on wind turbine aeroservoelastic modes and loads

    DEFF Research Database (Denmark)

    Tibaldi, Carlo; Henriksen, Lars Christian; Hansen, Morten Hartvig

    2014-01-01

    The eects of dierent gain-scheduling methods for a classical wind turbine controller, operating in full load region, on the wind turbine aeroservoelastic modes and loads are investigated in this work. The dierent techniques are derived looking at the physical problem to take into account the chan......The eects of dierent gain-scheduling methods for a classical wind turbine controller, operating in full load region, on the wind turbine aeroservoelastic modes and loads are investigated in this work. The dierent techniques are derived looking at the physical problem to take into account...

  12. Can road traffic mask sound from wind turbines? Response to wind turbine sound at different levels of road traffic sound

    International Nuclear Information System (INIS)

    Pedersen, Eja; Berg, Frits van den; Bakker, Roel; Bouma, Jelte

    2010-01-01

    Wind turbines are favoured in the switch-over to renewable energy. Suitable sites for further developments could be difficult to find as the sound emitted from the rotor blades calls for a sufficient distance to residents to avoid negative effects. The aim of this study was to explore if road traffic sound could mask wind turbine sound or, in contrast, increases annoyance due to wind turbine noise. Annoyance of road traffic and wind turbine noise was measured in the WINDFARMperception survey in the Netherlands in 2007 (n=725) and related to calculated levels of sound. The presence of road traffic sound did not in general decrease annoyance with wind turbine noise, except when levels of wind turbine sound were moderate (35-40 dB(A) Lden) and road traffic sound level exceeded that level with at least 20 dB(A). Annoyance with both noises was intercorrelated but this correlation was probably due to the influence of individual factors. Furthermore, visibility and attitude towards wind turbines were significantly related to noise annoyance of modern wind turbines. The results can be used for the selection of suitable sites, possibly favouring already noise exposed areas if wind turbine sound levels are sufficiently low.

  13. On Small-Signal Stability of Wind Power System with Full-Load Converter Interfaced Wind Turbines

    OpenAIRE

    Knüppel, Thyge; Akhmatov, Vladislav; Nielsen, Jørgen Nygård; Jensen, Kim H.; Dixon, Andrew; Østergaard, Jacob

    2010-01-01

    Small-signal stability analysis of power system oscillations is a well established field within power system analysis, but not much attention has yet been paid to systems with a high penetration of wind turbines and with large wind power plants. In this paper an analysis is presented which assess the impact of full-load converter interfaced wind turbines on power system small-signal stability. The study is based on a 7 generator network with lightly damped inter-area modes. A detailed wind tu...

  14. Coordinated Control of Wind Turbine and Energy Storage System for Reducing Wind Power Fluctuation

    Directory of Open Access Journals (Sweden)

    Chunghun Kim

    2017-12-01

    Full Text Available This paper proposes a method for the coordinated control of a wind turbine and an energy storage system (ESS. Because wind power (WP is highly dependent on wind speed, which is variable, severe stability problems can be caused in power systems, especially when the WP has a high penetration level. To solve this problem, many power generation corporations or grid operators have begun using ESSs. An ESS has very quick response and good performance for reducing the impact of WP fluctuation; however, its installation cost is high. Therefore, it is important to design the control algorithm by considering both the ESS capacity and WP fluctuation. Thus, we propose a control algorithm to mitigate the WP fluctuation by using the coordinated control between the wind turbine and the ESS by considering the ESS capacity and the WP fluctuation. Using de-loaded control, according to the WP fluctuation and ESS capacity, we can expand the ESS lifespan and improve grid reliability by avoiding the extreme value of state of charge (SoC (i.e., 0 or 1 pu. The effectiveness of the proposed method was validated via MATLAB/Simulink by considering a small power system that includes both a wind turbine generator and conventional generators that react to system frequency deviation. We found that the proposed method has better performance in SoC management, thereby improving the frequency regulation by mitigating the impact of the WP fluctuation on the small power system.

  15. High Power Electronics - Key Technology for Wind Turbines

    DEFF Research Database (Denmark)

    Blaabjerg, Frede; Ma, Ke

    2014-01-01

    In this chapter the developments of technology and market trends in wind power application are discussed. Different wind turbine concepts as well as some dominant and promising power converter solutions are reviewed respectively. Furthermore the control methods, grid demands as well as the emerging...... reliability challenges for the future wind turbines are explained. It is concluded that the wind turbine behavior/performance can be significantly improved by introducing power electronics, and there will be higher requirements for the power electronics performances in wind power application....

  16. The 1.5 MW wind turbine of tomorrow

    Energy Technology Data Exchange (ETDEWEB)

    De Wolff, T.J.; Sondergaard, H. [Nordtank Energy Group, Richmond, VA (United States)

    1996-12-31

    The Danish company Nordtank is one of the pioneers within the wind turbine industry. Since 1981 Nordtank has installed worldwide more than 2300 wind turbine generators with a total name plate capacity that is exceeding 350 MW. This paper will describe two major wind turbine technology developments that Nordtank has accomplished during the last year: Site Optimization of Nordtank wind turbines: Nordtank has developed a flexible design concept for its WTGs in the 500/600 kW range, in order to offer the optimal WTG solution for any given site and wind regime. Nordtank`s 1.5 MW wind turbine: In September 1995, Nordtank was the first company to install a commercial 1.5 NM WTG. This paper will document the development process, the design as well as operations of the Nordtank 1.5 MW WTG.

  17. Wall modeled LES of wind turbine wakes with geometrical effects

    Science.gov (United States)

    Bricteux, Laurent; Benard, Pierre; Zeoli, Stephanie; Moureau, Vincent; Lartigue, Ghislain; Vire, Axelle

    2017-11-01

    This study focuses on prediction of wind turbine wakes when geometrical effects such as nacelle, tower, and built environment, are taken into account. The aim is to demonstrate the ability of a high order unstructured solver called YALES2 to perform wall modeled LES of wind turbine wake turbulence. The wind turbine rotor is modeled using an Actuator Line Model (ALM) while the geometrical details are explicitly meshed thanks to the use of an unstructured grid. As high Reynolds number flows are considered, sub-grid scale models as well as wall modeling are required. The first test case investigated concerns a wind turbine flow located in a wind tunnel that allows to validate the proposed methodology using experimental data. The second test case concerns the simulation of a wind turbine wake in a complex environment (e.g. a Building) using realistic turbulent inflow conditions.

  18. Optimized Control Strategy For Over Loaded Offshore Wind Turbines

    DEFF Research Database (Denmark)

    Odgaard, Peter Fogh; Knudsen, Torben; Wisniewski, Rafal

    2015-01-01

    .g., the tower. In the process of decreasing the cost of energy of wind turbines it is relevant to continue some level of production while awaiting service and repair of the offshore wind turbine. This is typically done operating the wind turbine in a power de-rated operation mode, assuming that lower power...... controller tuning for a given wind turbine. It also enables a very safe and robust comparison between a new control strategy and the present one. Main body of abstract Is it true that power de-rating indeed the best way to reduce loads? The power de-rating approach has the drawback of only indirectly...... and service at offshore location, where accessibility can be problematic. The controller objectives are focused directly on the actual objective like lowering of fore aft fatigue loads, instead of using an indirect objective of de-rating the power production of the wind turbine. This means what the wind...

  19. Power curve of the AWEC-60 wind turbine

    International Nuclear Information System (INIS)

    Avia, F.

    1992-01-01

    The experimental wind turbine AWEC-60 was developed to evaluate the possibilities of the Large Wind turbines, from the technical and economical point of view. The project was developed by a spanish-german group, integrated by Union Fenosa, Asinel, M.A.N. Neue Technologie and the Instituto de Energias Renovables from CIEMAT, starting the operation during the year 1990. In this paper, the obtention of the wind turbine's power curve is presented, which has been obtained in agreement with the 'Recommended Practices for Wind Turbine Testing and Evaluation' from the Executive Committee for the Research and Development on Wind Energy, of the International Energy Agency (AIE). Using the functioning data of the wind turbine corresponding to the first quarter of the year 1991, the power curves have been obtained, and the results have been compared with the curves measured in other similar large windturbines. (author)

  20. Statistical fault diagnosis of wind turbine drivetrain applied to a 5MW floating wind turbine

    DEFF Research Database (Denmark)

    Ghane, Mahdi; Nejad, Amir R.; Blanke, Mogens

    2016-01-01

    to prevent them to develop into failure, statistical change detection is used in this paper. The Cumulative Sum Method (CUSUM) is employed to detect possible defects in the downwind main bearing. A high fidelity gearbox model on a 5-MW spar-type wind turbine is used to generate data for fault-free and faulty...