WorldWideScience

Sample records for local wind systems

  1. Local ownership, smart energy systems and better wind power economy

    DEFF Research Database (Denmark)

    Hvelplund, Frede; Möller, Bernd; Sperling, Karl

    2013-01-01

    Increasing wind power shares enhances the need to integrate wind power into the energy system and to improve its economy. In this study we propose two ways of achieving this end. One is to increase the value of wind power by integrating the heat and power markets, and thus ensures that wind power...... the acceptance rate of onshore wind. The economy of wind power is thus improved by both increasing its value and reducing its costs....

  2. Local and regional characterisation of the diurnal mountain wind systems in the Guadarrama mountain range (Spain)

    Science.gov (United States)

    Arrillaga, Jon A.; Cano, Darío; Sastre, Mariano; Román-Cascón, Carlos; Maqueda, Gregorio; Morales, Gema; Viana, Samuel; Inclán, Rosa M.; Fidel González-Roúco, J.; Santolaria, Edmundo; Durán, Luis; Yagüe, Carlos

    2017-04-01

    Diurnal mountain wind systems that develop in the surroundings of the Guadarrama mountain range (Spain) are studied in this work. This area is highly interesting: the city of Madrid is located at approximately 50 km towards the SE; and on the other hand, unlike in other mountainous regions, the summers are characterised to be significantly dry, providing an interesting case study of energy balance in the context of complex orography. Slope and basin circulations formed play an important role in the development of fog and pollution episodes in the whole region. On top of that, when upslope basin winds strengthened by diurnal convection exceed 10 m s-1, the runway configuration at the airport of Madrid needs to be modified. Continuous meteorological data and turbulent fluxes of carbon dioxide, water vapour, momentum and heat are provided since June 2016 from measurements at a 10 m tower at La Herrería site, which is located at the foot of the Guadarrama mountain range. Besides, a 4 m high portable station is available for complementary measurements. La Herrería is part of the Guadarrama Monitoring Network (GuMNet; www.ucm.es/gumnet/), an atmospheric and subsurface observational facility distributed over the Guadarrama mountain range. As a support for the analysis, data from conventional meteorological stations within the region and a wind profiler at the airport are also employed. The wind roses for the period analysed (summer 2016) show how the diurnal cycle of the flows is influenced by local slopes and by the configuration of the basin. The irruption of the downslope flow in the evening produces a significant increase of the turbulence intensity and the eventual breakdown of the surface-based thermal inversion. However, the severe drying out of the soil throughout the summer, evident from the evolution of the surface latent and sensible heat fluxes, seems to play a role in altering the characteristics of the mountain-breeze system and its impact on turbulence

  3. Small Wind Energy Systems

    DEFF Research Database (Denmark)

    Simoes, Marcelo; Farret, Felix Alberto; Blaabjerg, Frede

    2015-01-01

    devices, and a centralized distribution control. In order to establish a small wind energy system it is important to observe the following: (i) Attending the energy requirements of the actual or future consumers; (ii) Establishing civil liabilities in case of accidents and financial losses due to shortage...... or low quality of energy; (iii) Negotiating collective conditions to interconnect the microgrid with the public network or with other sources of energy that is independent of wind resources; (iv) Establishing a performance criteria of power quality and reliability to end-users, in order to reduce costs...... and guaranteeing an acceptable energy supply. This paper discuss how performance is affected by local conditions and random nature of the wind, power demand profiles, turbine related factors, and presents the technical issues for implementing a self-excited induction generator system, or a permanent magnet based...

  4. Remote Sensing Wind and Wind Shear System.

    Science.gov (United States)

    Contents: Remote sensing of wind shear and the theory and development of acoustic doppler; Wind studies; A comparison of methods for the remote detection of winds in the airport environment; Acoustic doppler system development; System calibration; Airport operational tests.

  5. LiDAR-based 2D Localization and Mapping System using Elliptical Distance Correction Models for UAV Wind Turbine Blade Inspection

    DEFF Research Database (Denmark)

    Nikolov, Ivan Adriyanov; Madsen, Claus B.

    2017-01-01

    The wind energy sector faces a constant need for annual inspections of wind turbine blades for damage, erosion and cracks. These inspections are an important part of the wind turbine life cycle and can be very costly and hazardous to specialists. This has led to the use of automated drone...... inspections and the need for accurate, robust and inexpensive systems for localization of drones relative to the wing. Due to the lack of visual and geometrical features on the wind turbine blade, conventional SLAM algorithms have a limited use. We propose a cost-effective, easy to implement and extend system...

  6. Summertime wind climate in Yerevan: valley wind systems

    Science.gov (United States)

    Gevorgyan, Artur

    2017-03-01

    1992-2014 wind climatology analysis in Yerevan is presented with particular focus given to the summertime thermally induced valley wind systems. Persistence high winds are observed in Yerevan during July-August months when the study region is strongly affected by a heat-driven plain-plateau circulation. The local valley winds arrive in Yerevan in the evening hours, generally, from 1500 to 1800 UTC, leading to rapid enhancement of wind speeds and dramatic changes in wind direction. Valley-winds significantly impact the local climate of Yerevan, which is a densely populated city. These winds moderate evening temperatures after hot and dry weather conditions observed during summertime afternoons. On the other hand, valley winds result in significantly higher nocturnal temperatures and more frequent occurrence of warm nights (tn90p) in Yerevan due to stronger turbulent mixing of boundary layer preventing strong surface cooling and temperature drop in nighttime and morning hours. The applied WRF-ARW limited area model is able to simulate the key features of the observed spatial pattern of surface winds in Armenia associated with significant terrain channeling, wind curls, etc. By contrast, ECMWF EPS global model fails to capture mesoscale and local wind systems over Armenia. However, the results of statistical verification of surface winds in Yerevan showed that substantial biases are present in WRF 18-h wind forecasts, as well as, the temporal variability of observed surface winds is not reproduced adequately in WRF-ARW model.

  7. Detection and Localization of Tooth Breakage Fault on Wind Turbine Planetary Gear System considering Gear Manufacturing Errors

    Directory of Open Access Journals (Sweden)

    Y. Gui

    2014-01-01

    Full Text Available Sidebands of vibration spectrum are sensitive to the fault degree and have been proved to be useful for tooth fault detection and localization. However, the amplitude and frequency modulation due to manufacturing errors (which are inevitable in actual planetary gear system lead to much more complex sidebands. Thus, in the paper, a lumped parameter model for a typical planetary gear system with various types of errors is established. In the model, the influences of tooth faults on time-varying mesh stiffness and tooth impact force are derived analytically. Numerical methods are then utilized to obtain the response spectra of the system with tooth faults with and without errors. Three system components (including sun, planet, and ring gears with tooth faults are considered in the discussion, respectively. Through detailed comparisons of spectral sidebands, fault characteristic frequencies of the system are acquired. Dynamic experiments on a planetary gear-box test rig are carried out to verify the simulation results and these results are of great significances for the detection and localization of tooth faults in wind turbines.

  8. Wind Energy Systems.

    Science.gov (United States)

    Conservation and Renewable Energy Inquiry and Referral Service (DOE), Silver Spring, MD.

    During the 1920s and 1930s, millions of wind energy systems were used on farms and other locations far from utility lines. However, with passage of the Rural Electrification Act in 1939, cheap electricity was brought to rural areas. After that, the use of wind machines dramatically declined. Recently, the rapid rise in fuel prices has led to a…

  9. Moriah Wind System Laboratory

    Data.gov (United States)

    Federal Laboratory Consortium — Purpose: The Moriah Wind System Laboratory provides in-service support for the more than 50 U.S. Navy, U.S. Coast Guard and Military Sealift Command ships on which...

  10. 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.

  11. Are local wind power resources well estimated?

    Science.gov (United States)

    Lundtang Petersen, Erik; Troen, Ib; Jørgensen, Hans E.; Mann, Jakob

    2013-03-01

    Planning and financing of wind power installations require very importantly accurate resource estimation in addition to a number of other considerations relating to environment and economy. Furthermore, individual wind energy installations cannot in general be seen in isolation. It is well known that the spacing of turbines in wind farms is critical for maximum power production. It is also well established that the collective effect of wind turbines in large wind farms or of several wind farms can limit the wind power extraction downwind. This has been documented by many years of production statistics. For the very large, regional sized wind farms, a number of numerical studies have pointed to additional adverse changes to the regional wind climate, most recently by the detailed studies of Adams and Keith [1]. They show that the geophysical limit to wind power production is likely to be lower than previously estimated. Although this problem is of far future concern, it has to be considered seriously. In their paper they estimate that a wind farm larger than 100 km2 is limited to about 1 W m-2. However, a 20 km2 off shore farm, Horns Rev 1, has in the last five years produced 3.98 W m-2 [5]. In that light it is highly unlikely that the effects pointed out by [1] will pose any immediate threat to wind energy in coming decades. Today a number of well-established mesoscale and microscale models exist for estimating wind resources and design parameters and in many cases they work well. This is especially true if good local data are available for calibrating the models or for their validation. The wind energy industry is still troubled by many projects showing considerable negative discrepancies between calculated and actually experienced production numbers and operating conditions. Therefore it has been decided on a European Union level to launch a project, 'The New European Wind Atlas', aiming at reducing overall uncertainties in determining wind conditions. The

  12. Small Wind Energy Systems

    DEFF Research Database (Denmark)

    2017-01-01

    This chapter intends to serve as a brief guide when someone is considering the use of wind energy for small power applications. It is discussed that small wind energy systems act as the major energy source for residential or commercial applications, or how to make it part of a microgrid...... as a distributed generator. In this way, sources and loads are connected in such a way to behave as a renewable dispatch center. With this regard, non-critical loads might be curtailed or shed during times of energy shortfall or periods of high costs of energy production. If such a wind energy system is connected...... to the public distibutor, it can serve as a backup system, as a non-interruptible power supply (with storage aggregation), provide low-voltage support, or give a clean surplus of energy transferred to the public network under economical and technological basis. In this chapter, several factors are also...

  13. Local and Regional Impacts of Large Scale Wind Energy Deployment

    Science.gov (United States)

    Michalakes, J.; Hammond, S.; Lundquist, J. K.; Moriarty, P.; Robinson, M.

    2010-12-01

    The U.S. is currently on a path to produce 20% of its electricity from wind energy by 2030, almost a 10-fold increase over present levels of electricity generated from wind. Such high-penetration wind energy deployment will entail extracting elevated energy levels from the planetary boundary layer and preliminary studies indicate that this will have significant but uncertain impacts on the local and regional environment. State and federal regulators have raised serious concerns regarding potential agricultural impacts from large farms deployed throughout the Midwest where agriculture is the basis of the local economy. The effects of large wind farms have been proposed to be both beneficial (drying crops to reduce occurrences of fungal diseases, avoiding late spring freezes, enhancing pollen viability, reducing dew duration) and detrimental (accelerating moisture loss during drought) with no conclusive investigations thus far. As both wind and solar technologies are deployed at scales required to replace conventional technologies, there must be reasonable certainty that the potential environmental impacts at the micro, macro, regional and global scale do not exceed those anticipated from carbon emissions. Largely because of computational limits, the role of large wind farms in affecting regional-scale weather patterns has only been investigated in coarse simulations and modeling tools do not yet exist which are capable of assessing the downwind affects of large wind farms may have on microclimatology. In this presentation, we will outline the vision for and discuss technical and scientific challenges in developing a multi-model high-performance simulation capability covering the range of mesoscale to sub-millimeter scales appropriate for assessing local, regional, and ultimately global environmental impacts and quantifying uncertainties of large scale wind energy deployment scenarios. Such a system will allow continuous downscaling of atmospheric processes on wind

  14. LiDAR-based Localization and Mapping System using Ellipse Distance Correction Models for UAV Wind Turbine Blade Inspection

    DEFF Research Database (Denmark)

    Nikolov, Ivan Adriyanov; Madsen, Claus B.

    2016-01-01

    The wind energy sector faces a constant need for annual inspections of wind turbine blades for damage, erosion and cracks. These inspections are an important part of the wind turbine life cycle and can be very constly and hazardous to specialists. This has led to the use of automated drone...

  15. Wind power in power systems

    CERN Document Server

    Ackermann, Thomas

    2012-01-01

    The second edition of the highly acclaimed Wind Power in Power Systems has been thoroughly revised and expanded to reflect the latest challenges associated with increasing wind power penetration levels. Since its first release, practical experiences with high wind power penetration levels have significantly increased. This book presents an overview of the lessons learned in integrating wind power into power systems and provides an outlook of the relevant issues and solutions to allow even higher wind power penetration levels. This includes the development of standard wind turbine sim

  16. Wind Powered Sprinkler System

    Directory of Open Access Journals (Sweden)

    Chin Jung Huang

    2013-06-01

    Full Text Available Due to limited energy resources, excessive emission of CO2, global warming, increase of mean temperature, serious impacts have resulted on our living environment, and thus, energy saving and carbon reduction have become urgent issues. Planting grass, flowers and trees can absorb and reduce CO2, thus meeting the requirements for energy saving and carbon reduction in environmental protection. At present, most of lawns or gardens in Taiwan are maintained by manual or traditional semiautomatic watering device. Whether the lawn needs to be watered and the amount of water to be sprinkled depends on subjective decision. When the lawn is watered without examining the moisture content of the soil beforehand, it causes waste of time, labor, water and cost. The intelligent wind powered watering system developed by this study used an electromechanical integrated design system to control the humidity probe, and used the electricity generated by natural wind power and pumping device to control the sprinkling action. This system sprinkles water by sensing the soil moisture content, and stops sprinkling automatically when the soil moisture content is enough, thus achieving the purposes of cost and energy saving.

  17. 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......This study presents wind turbine converter stability analysis of wind farms in frequency domain. The interaction between the wind turbine control system and the wind farm structure in wind farms is deeply investigated. Two wind farms (i.e. Horns Rev II and Karnice) are taken into consideration....... The same wind turbine converter control strategy is evaluated in two different wind farms. It is emphasised that the grid-side converter controller should be characterised by sufficient harmonic/noise rejection and adjusted depending on wind farms to which it is connected. Various stability indices...

  18. 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

    . The same wind turbine converter control strategy is evaluated in two different wind farms. It is emphasised that the grid-side converter controller should be characterised by sufficient harmonic/noise rejection and adjusted depending on wind farms to which it is connected. Various stability indices......This study presents wind turbine converter stability analysis of wind farms in frequency domain. The interaction between the wind turbine control system and the wind farm structure in wind farms is deeply investigated. Two wind farms (i.e. Horns Rev II and Karnice) are taken into consideration...... 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...

  19. Developing a Local Neurofuzzy Model for Short-Term Wind Power Forecasting

    Directory of Open Access Journals (Sweden)

    E. Faghihnia

    2014-01-01

    Full Text Available Large scale integration of wind generation capacity into power systems introduces operational challenges due to wind power uncertainty and variability. Therefore, accurate wind power forecast is important for reliable and economic operation of the power systems. Complexities and nonlinearities exhibited by wind power time series necessitate use of elaborative and sophisticated approaches for wind power forecasting. In this paper, a local neurofuzzy (LNF approach, trained by the polynomial model tree (POLYMOT learning algorithm, is proposed for short-term wind power forecasting. The LNF approach is constructed based on the contribution of local polynomial models which can efficiently model wind power generation. Data from Sotavento wind farm in Spain was used to validate the proposed LNF approach. Comparison between performance of the proposed approach and several recently published approaches illustrates capability of the LNF model for accurate wind power forecasting.

  20. Wind Fins: Novel Lower-Cost Wind Power System

    Energy Technology Data Exchange (ETDEWEB)

    David C. Morris; Dr. Will D. Swearingen

    2007-10-08

    This project evaluated the technical feasibility of converting energy from the wind with a novel “wind fin” approach. This patent-pending technology has three major components: (1) a mast, (2) a vertical, hinged wind structure or fin, and (3) a power takeoff system. The wing structure responds to the wind with an oscillating motion, generating power. The overall project goal was to determine the basic technical feasibility of the wind fin technology. Specific objectives were the following: (1) to determine the wind energy-conversion performance of the wind fin and the degree to which its performance could be enhanced through basic design improvements; (2) to determine how best to design the wind fin system to survive extreme winds; (3) to determine the cost-effectiveness of the best wind fin designs compared to state-of-the-art wind turbines; and (4) to develop conclusions about the overall technical feasibility of the wind fin system. Project work involved extensive computer modeling, wind-tunnel testing with small models, and testing of bench-scale models in a wind tunnel and outdoors in the wind. This project determined that the wind fin approach is technically feasible and likely to be commercially viable. Project results suggest that this new technology has the potential to harvest wind energy at approximately half the system cost of wind turbines in the 10kW range. Overall, the project demonstrated that the wind fin technology has the potential to increase the economic viability of small wind-power generation. In addition, it has the potential to eliminate lethality to birds and bats, overcome public objections to the aesthetics of wind-power machines, and significantly expand wind-power’s contribution to the national energy supply.

  1. Cost of wind energy: comparing distant wind resources to local resources in the midwestern United States.

    Science.gov (United States)

    Hoppock, David C; Patiño-Echeverri, Dalia

    2010-11-15

    The best wind sites in the United States are often located far from electricity demand centers and lack transmission access. Local sites that have lower quality wind resources but do not require as much power transmission capacity are an alternative to distant wind resources. In this paper, we explore the trade-offs between developing new wind generation at local sites and installing wind farms at remote sites. We first examine the general relationship between the high capital costs required for local wind development and the relatively lower capital costs required to install a wind farm capable of generating the same electrical output at a remote site,with the results representing the maximum amount an investor should be willing to pay for transmission access. We suggest that this analysis can be used as a first step in comparing potential wind resources to meet a state renewable portfolio standard (RPS). To illustrate, we compare the cost of local wind (∼50 km from the load) to the cost of distant wind requiring new transmission (∼550-750 km from the load) to meet the Illinois RPS. We find that local, lower capacity factor wind sites are the lowest cost option for meeting the Illinois RPS if new long distance transmission is required to access distant, higher capacity factor wind resources. If higher capacity wind sites can be connected to the existing grid at minimal cost, in many cases they will have lower costs.

  2. Wind Power in Electrical Distribution Systems

    DEFF Research Database (Denmark)

    Chen, Zhe

    2013-01-01

    Recent years, wind power is experiencing a rapid growth, large number of wind turbines/wind farms have been installed and connected to power systems. In addition to the large centralised wind farms connected to transmission grids, many distributed wind turbines and wind farms are operated as dist...

  3. Wind Power in Electrical Distribution Systems

    DEFF Research Database (Denmark)

    Chen, Zhe

    2013-01-01

    as distributed generators in distribution systems. This paper discusses the issues of wind turbines in distribution systems. Wind power conversion systems briefly introduced, the basic features and technical characteristics of distributed wind power system are described, and the main technical demands......Recent years, wind power is experiencing a rapid growth, large number of wind turbines/wind farms have been installed and connected to power systems. In addition to the large centralised wind farms connected to transmission grids, many distributed wind turbines and wind farms are operated...

  4. Efficient utilization of wind power: Long-distance transmission or local consumption?

    Science.gov (United States)

    Sun, Yuanzhang; Ma, Xiyuan; Xu, Jian; Bao, Yi; Liao, Siyang

    2017-09-01

    Excess wind power produced in wind-intensive areas is normally delivered to remote load centers via long-distance transmission lines. This paper presents a comparison between long-distance transmission, which has gained popularity, and local energy consumption, in which a fraction of the generated wind power can be locally consumed by energy-intensive industries. First, the challenges and solutions to the long-distance transmission and local consumption of wind power are presented. Then, the two approaches to the utilization of wind power are compared in terms of system security, reliability, cost, and capability to utilize wind energy. Finally, the economic feasibility and technical feasibility of the local consumption of wind power are demonstrated by a large and isolated industrial power system, or supermicrogrid, in China. The coal-fired generators together with the short-term interruptible electrolytic aluminum load in the supermicrogrid are able to compensate for the intermittency of wind power. In the long term, the transfer of high-energy-consumption industries to wind-rich areas and their local consumption of the available wind power are beneficial.

  5. Integrated roof wind energy system

    Directory of Open Access Journals (Sweden)

    Moonen S.P.G.

    2012-10-01

    Full Text Available Wind is an attractive renewable source of energy. Recent innovations in research and design have reduced to a few alternatives with limited impact on residential construction. Cost effective solutions have been found at larger scale, but storage and delivery of energy to the actual location it is used, remain a critical issue. The Integrated Roof Wind Energy System is designed to overcome the current issues of urban and larger scale renewable energy system. The system is built up by an axial array of skewed shaped funnels that make use of the Venturi Effect to accelerate the wind flow. This inventive use of shape and geometry leads to a converging air capturing inlet to create high wind mass flow and velocity toward a vertical-axis wind turbine in the top of the roof for generation of a relatively high amount of energy. The methods used in this overview of studies include an array of tools from analytical modelling, PIV wind tunnel testing, and CFD simulation studies. The results define the main design parameters for an efficient system, and show the potential for the generation of high amounts of renewable energy with a novel and effective system suited for the built environment.

  6. Integrated roof wind energy system

    Science.gov (United States)

    Suma, A. B.; Ferraro, R. M.; Dano, B.; Moonen, S. P. G.

    2012-10-01

    Wind is an attractive renewable source of energy. Recent innovations in research and design have reduced to a few alternatives with limited impact on residential construction. Cost effective solutions have been found at larger scale, but storage and delivery of energy to the actual location it is used, remain a critical issue. The Integrated Roof Wind Energy System is designed to overcome the current issues of urban and larger scale renewable energy system. The system is built up by an axial array of skewed shaped funnels that make use of the Venturi Effect to accelerate the wind flow. This inventive use of shape and geometry leads to a converging air capturing inlet to create high wind mass flow and velocity toward a vertical-axis wind turbine in the top of the roof for generation of a relatively high amount of energy. The methods used in this overview of studies include an array of tools from analytical modelling, PIV wind tunnel testing, and CFD simulation studies. The results define the main design parameters for an efficient system, and show the potential for the generation of high amounts of renewable energy with a novel and effective system suited for the built environment.

  7. Wind power plant system services

    DEFF Research Database (Denmark)

    Basit, Abdul; Altin, Müfit

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

  8. Short-term prediction of local wind conditions

    DEFF Research Database (Denmark)

    Landberg, L.; Watson, S.J.

    1994-01-01

    Using Numerical Weather Prediction (NWP) models it has been shown that they, combined with models (either physical or statistical) taking local effects into account, can be used to predict the wind locally better than the models commonly used today (as eg persistence). By ''local'' is meant at one...... law, and the logarithmic wind profile. The predictions are made up to 36 hours ahead. The model is tested on data from 50 meteorological stations scattered all over Europe....

  9. Wind Energy Conversion Systems Technology and Trends

    CERN Document Server

    2012-01-01

    Wind Energy Conversion System covers the technological progress of wind energy conversion systems, along with potential future trends. It includes recently developed wind energy conversion systems such as multi-converter operation of variable-speed wind generators, lightning protection schemes, voltage flicker mitigation and prediction schemes for advanced control of wind generators. Modeling and control strategies of variable speed wind generators are discussed, together with the frequency converter topologies suitable for grid integration. Wind Energy Conversion System also describes offshore farm technologies including multi-terminal topology and space-based wind observation schemes, as well as both AC and DC based wind farm topologies. The stability and reliability of wind farms are discussed, and grid integration issues are examined in the context of the most recent industry guidelines. Wind power smoothing, one of the big challenges for transmission system operators, is a particular focus. Fault ride th...

  10. Wind in the Solar System

    Science.gov (United States)

    McIntosh, Gordon

    2010-01-01

    As an astronomy instructor I am always looking for commonly experienced Earthly phenomena to help my students and me understand and appreciate similar occurrences elsewhere in the solar system. Recently I wrote short "TPT" articles on frost and precipitation. The present article is on winds in the solar system. A windy day or storm might…

  11. Wind in the Solar System

    Science.gov (United States)

    McIntosh, Gordon

    2010-01-01

    As an astronomy instructor I am always looking for commonly experienced Earthly phenomena to help my students and me understand and appreciate similar occurrences elsewhere in the solar system. Recently I wrote short "TPT" articles on frost and precipitation. The present article is on winds in the solar system. A windy day or storm might motivate…

  12. Wind in the Solar System

    Science.gov (United States)

    McIntosh, Gordon

    2010-01-01

    As an astronomy instructor I am always looking for commonly experienced Earthly phenomena to help my students and me understand and appreciate similar occurrences elsewhere in the solar system. Recently I wrote short "TPT" articles on frost and precipitation. The present article is on winds in the solar system. A windy day or storm might…

  13. Local and Regional Winds: Their Names and Attributes,

    Science.gov (United States)

    1982-03-30

    of the European part of the USSR, in the USA, and in Australia; white storms are also observed, but rarely, arising over saline or salt-bearing soils...and in the Persian Gulf; this term is also used in Djezirg [4]. Sahat -- a local term for the sirocco wind in Morocco [23]. Sahel -- strong wind

  14. Wind loads on solar energy systems

    NARCIS (Netherlands)

    Kampen, B.J.M. van; Geurts, C.P.W.; Borsboom, W.A.; Blackmore, P.

    2005-01-01

    Wind loads on solar energy systems are not covered by current wind loading standards. This paper describes results of a parametric study into the wind loads 0on solar energy systems,. which are placed on flat roofs. Wind tunnel measurements have been carried out on a number of configurations. The

  15. Wind loads on solar energy systems

    NARCIS (Netherlands)

    Kampen, B.J.M. van; Geurts, C.P.W.; Borsboom, W.A.; Blackmore, P.

    2005-01-01

    Wind loads on solar energy systems are not covered by current wind loading standards. This paper describes results of a parametric study into the wind loads 0on solar energy systems,. which are placed on flat roofs. Wind tunnel measurements have been carried out on a number of configurations. The re

  16. Wind loads on solar energy systems

    NARCIS (Netherlands)

    Kampen, B.J.M. van; Geurts, C.P.W.; Borsboom, W.A.; Blackmore, P.

    2005-01-01

    Wind loads on solar energy systems are not covered by current wind loading standards. This paper describes results of a parametric study into the wind loads 0on solar energy systems,. which are placed on flat roofs. Wind tunnel measurements have been carried out on a number of configurations. The re

  17. Hydraulic wind energy conversion system

    Energy Technology Data Exchange (ETDEWEB)

    1981-07-01

    The purpose of this research was to design, build and test a hydraulic wind energy system. This design used a three bladed turbine, which drove a hydraulic pump. The energy is transmitted from the pump through a long hose and into a hydraulic motor, where the energy is used. This wind system was built and tested during the winter of 1980-1981. The power train included a five meter, three bladed wind turbine, a 9.8:1 ratio gearbox, a 1.44 cubic inch displacement pump with a small supercharge gear pump attached. The hydraulic fluid was pumped through a 70', 3/4'' I-D-high pressure flexhose, then through a volume control valve and into a 1.44 cubic inch displacement motor. The fluid was returned through a 70', 1'' I-D-flexhose.

  18. Wind energy XXL. Creating local advantages

    Energy Technology Data Exchange (ETDEWEB)

    Iken, Joern; Thomas, Torsten

    2010-07-01

    Still in its infancy, the wind energy industry is rapidly developing into a global business. Research institutes around the globe are working to develop the next technological advances. Tomorrow's turbines will be more efficient, generate more power, and be less expensive. (orig.)

  19. SMES for wind energy systems

    Science.gov (United States)

    Paul Antony, Anish

    simulation results the utility of SMES in voltage sag mitigation for momentary interruptions. The 1MJ SMES mitigates voltage sags for a useful duration ~50 seconds. In conclusion (Chapter 7), we believe that in this dissertation, we have documented the design of SMES for both momentary and sustained interruptions in wind turbines. We have put forth some novel and relevant hypotheses, developed and performed suitable simulation studies to validate these hypotheses. By doing so, we have been able to expand our knowledge in our quest to grasp the underlying mechanisms of storage systems in wind energy integration. Although the resulting analysis has allowed us to gain valuable insight, we feel that it is only the tip of the iceberg, and that many yet unknown discoveries are to be made. We remain hopeful that the future of SMES for wind energy will only look brighter from here onward. (Abstract shortened by UMI.).

  20. Distributed Energy Systems with Wind Power and Energy Storage

    OpenAIRE

    Korpås, Magnus

    2004-01-01

    The topic of this thesis is the study of energy storage systems operating with wind power plants. The motivation for applying energy storage in this context is that wind power generation is intermittent and generally difficult to predict, and that good wind energy resources are often found in areas with limited grid capacity. Moreover, energy storage in the form of hydrogen makes it possible to provide clean fuel for transportation. The aim of this work has been to evaluate how local energy s...

  1. Distributed Energy Systems with Wind Power and Energy Storage

    OpenAIRE

    Korpås, Magnus

    2004-01-01

    The topic of this thesis is the study of energy storage systems operating with wind power plants. The motivation for applying energy storage in this context is that wind power generation is intermittent and generally difficult to predict, and that good wind energy resources are often found in areas with limited grid capacity. Moreover, energy storage in the form of hydrogen makes it possible to provide clean fuel for transportation. The aim of this work has been to evaluate how local energy s...

  2. An Appropriate Wind Model for Wind Integrated Power Systems Reliability Evaluation Considering Wind Speed Correlations

    Directory of Open Access Journals (Sweden)

    Rajesh Karki

    2013-02-01

    Full Text Available Adverse environmental impacts of carbon emissions are causing increasing concerns to the general public throughout the world. Electric energy generation from conventional energy sources is considered to be a major contributor to these harmful emissions. High emphasis is therefore being given to green alternatives of energy, such as wind and solar. Wind energy is being perceived as a promising alternative. This source of energy technology and its applications have undergone significant research and development over the past decade. As a result, many modern power systems include a significant portion of power generation from wind energy sources. The impact of wind generation on the overall system performance increases substantially as wind penetration in power systems continues to increase to relatively high levels. It becomes increasingly important to accurately model the wind behavior, the interaction with other wind sources and conventional sources, and incorporate the characteristics of the energy demand in order to carry out a realistic evaluation of system reliability. Power systems with high wind penetrations are often connected to multiple wind farms at different geographic locations. Wind speed correlations between the different wind farms largely affect the total wind power generation characteristics of such systems, and therefore should be an important parameter in the wind modeling process. This paper evaluates the effect of the correlation between multiple wind farms on the adequacy indices of wind-integrated systems. The paper also proposes a simple and appropriate probabilistic analytical model that incorporates wind correlations, and can be used for adequacy evaluation of multiple wind-integrated systems.

  3. 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....

  4. Wind energy systems information user study

    Energy Technology Data Exchange (ETDEWEB)

    Belew, W.W.; Wood, B.L.; Marle, T.L.; Reinhardt, C.L.

    1981-01-01

    This report describes the results of a series of telephone interviews with potential users of information on wind energy conversion. These interviews, part of a larger study covering nine different solar technologies, attempted to identify: the type of information each distinctive group of information users needed, and the best way of getting information to that group. Groups studied include: wind energy conversion system researchers; wind energy conversion system manufacturer representatives; wind energy conversion system distributors; wind turbine engineers; utility representatives; educators; county agents and extension service agents; and wind turbine owners.

  5. Wind power in modern power systems

    DEFF Research Database (Denmark)

    Chen, Zhe

    2013-01-01

    In recent years, wind power is experiencing a rapid growth, and large-scale wind turbines/wind farms have been developed and connected to power systems. However, the traditional power system generation units are centralized located synchronous generators with different characteristics compared...... with wind turbines. This paper presents an overview of the issues about integrating large-scale wind power plants into modern power systems. Firstly, grid codes are introduced. Then, the main technical problems and challenges are presented. Finally, some possible technical solutions are discussed....

  6. Influence of local wind speed and direction on wind power dynamics – Application to offshore very short-term forecasting

    DEFF Research Database (Denmark)

    Gallego, Cristobal; Pinson, Pierre; Madsen, Henrik

    2011-01-01

    Wind power time series usually show complex dynamics mainly due to non-linearities related to the wind physics and the power transformation process in wind farms. This article provides an approach to the incorporation of observed local variables (wind speed and direction) to model some of these e......Wind power time series usually show complex dynamics mainly due to non-linearities related to the wind physics and the power transformation process in wind farms. This article provides an approach to the incorporation of observed local variables (wind speed and direction) to model some...... of these effects by means of statistical models. To this end, a benchmarking between two different families of varyingcoefficient models (regime-switching and conditional parametric models) is carried out. The case of the offshore wind farm of Horns Rev in Denmark has been considered. The analysis is focused...... underlying effects in the dynamics of wind power time series....

  7. Twin signal signature sensing: Application to shorted winding monitoring, detection and localization

    Energy Technology Data Exchange (ETDEWEB)

    Streifel, R.J.; Marks, R.J.; El-Sharkawi, A.E.; Kerszenbaum, I. [Univ. of Washington, Seattle, WA (United States)

    1995-12-31

    Using twin signal sensing we propose a method to monitor, detect and localize shorts in power system devices with windings: including rotors, transformers and motors. There has, to date, been no effective way to do so. The most obvious approach, time domain reflectometry, fails due to the reactive coupling of the windings. Twin signal signature sensing of shorts results from identical signals being simultaneously injected in both sides of the windings. The reflected signals are measured and the difference amplified to produce the signature signal. The signature signal characterizes the current state of the windings. When winding shorts are present, the electrical characteristics of the device will be different and thus the signature signal will also change. The changes in the signature signal can be monitored to detect shorted windings. While a device is in operation, the signature signals can be monitored and the development of winding shorts can be diagnosed through the process of novelty detection. After a device is cleaned or otherwise known to be functioning correctly (no winding shorts), signature signals can be collected which represent the healthy device. If a sufficient number of signals can be collected, the signal space representing healthy windings can be characterized. A detection surface can be placed around the healthy signature signals to provide a partition of the signal space into two regions: healthy and faulty. Any signature signal which is not within the healthy signature partition will indicate a faulted device.

  8. 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.

  9. Wind-solar Hybrid Power System

    OpenAIRE

    Jin, Fei

    2014-01-01

    In the development and utilization of new energy sources, the solar energy and wind energy are paid more attention by various countries, and have become a new field of energy development and utilization of the highest level, the most mature technology, the most widely used and commercial development conditions for new energy. But both the traditional wind power system and solar power system have the characteristic of energy instability. Therefore, wind-solar hybrid power system was proposed i...

  10. WIND ENERGY CONVERSION SYSTEMS - A TECHNICAL REVIEW

    Directory of Open Access Journals (Sweden)

    N. RAMESH BABU

    2013-08-01

    Full Text Available Wind power production has been under the main focus for the past decade in power production and tremendous amount of research work is going on renewable energy, specifically on wind power extraction. Wind power provides an eco-friendly power generation and helps to meet the national energy demand when there is a diminishing trend in terms of non-renewable resources. This paper reviews the modeling of Wind Energy Conversion Systems (WECS, control strategies of controllers and various Maximum Power Point Tracking (MPPT technologies that are being proposed for efficient production of wind energy from the available resource.

  11. AUTONOMOUS WIND POWER INSTALLATIONS AND SYSTEMS

    Directory of Open Access Journals (Sweden)

    Kvitko A. V.

    2015-10-01

    Full Text Available The article shows the main advantages and disadvantages of renewable energy sources. It is shown, that in general, the use of renewable energy in the world has acquired real momentum and stable growth trend. An interesting fact is that the greatest application was currently the most mutable and unstable form of energy - wind. The total global installed capacity of large wind turbines, according to various estimates, is approximately 20 GW. This is because the specific investment in wind power is lower than with most other forms of renewable energy. The article presents features of the design and operation of modern wind power stations. It is shown that when choosing wind power plants and stations we must take into account the following main parameters and factors: the average value of amount of electricity consumed by power consumers on a monthly basis; power generator; uptime in the absence wind or when weak wind. The study shows block-circuit solutions of different options of energy systems made using wind power plants. We have also disclosed prospects of development wind energy and considered the advantages and the features of the choice of the main functional units of wind power stations which will increase the effectiveness of predesign work on the creation of high-performance systems of electrosupply with combined power supply systems based on renewable energy sources

  12. Downscaling of Airborne Wind Energy Systems

    Science.gov (United States)

    Fechner, Uwe; Schmehl, Roland

    2016-09-01

    Airborne wind energy systems provide a novel solution to harvest wind energy from altitudes that cannot be reached by wind turbines with a similar nominal generator power. The use of a lightweight but strong tether in place of an expensive tower provides an additional cost advantage, next to the higher capacity factor and much lower total mass. This paper investigates the scaling effects of airborne wind energy systems. The energy yield of airborne wind energy systems, that work in pumping mode of operation is at least ten times higher than the energy yield of conventional solar systems. For airborne wind energy systems the yield is defined per square meter wing area. In this paper the dependency of the energy yield on the nominal generator power for systems in the range of 1 kW to 1 MW is investigated. For the onshore location Cabauw, The Netherlands, it is shown, that a generator of just 1.4 kW nominal power and a total system mass of less than 30 kg has the theoretical potential to harvest energy at only twice the price per kWh of large scale airborne wind energy systems. This would make airborne wind energy systems a very attractive choice for small scale remote and mobile applications as soon as the remaining challenges for commercialization are solved.

  13. 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......This paper presents stability analysis of wind farms in frequency domain. The interaction between the wind turbine control system and the wind farm structure in wind farms is deeply investigated. Two wind farms (i.e. Horns Rev II and Karnice) are taken in to consideration in the study. It is shown...

  14. Long-Range WindScanner System

    DEFF Research Database (Denmark)

    Vasiljevic, Nikola; Lea, Guillaume; Courtney, Michael

    2016-01-01

    The technical aspects of a multi-Doppler LiDAR instrument, the long-range WindScanner system, are presented accompanied by an overview of the results from several field campaigns. The long-range WindScanner system consists of three spatially-separated, scanning coherent Doppler LiDARs and a remot...

  15. Kongiganak Wind Turbine Replacement and System Upgrade Project

    Energy Technology Data Exchange (ETDEWEB)

    Boonstra, Patrick [Intelligent Energy Systems, Anchorage, AK (United States)

    2016-12-13

    The Native Village of Kongiganak, Alaska was awarded a grant to upgrade the braking systems on five wind turbines and upgrade the monitoring and data collection unit to insure that enough energy is available to power the utility. The project manager for this award is Intelligent Energy Systems, LLC located in Anchorage, Alaska. In addition to accomplishing these upgrades, it was the intent for a local wind tech crew to be trained in Kongiganak so that routine maintenance and future repairs will be made by local workers.

  16. Solar energy system with wind vane

    Energy Technology Data Exchange (ETDEWEB)

    Grip, Robert E

    2015-11-03

    A solar energy system including a pedestal defining a longitudinal axis, a frame that is supported by the pedestal and that is rotateable relative to the pedestal about the longitudinal axis, the frame including at least one solar device, and a wind vane operatively connected to the frame to urge the frame relative to the pedestal about the longitudinal axis in response to wind acting on the wind vane.

  17. Monitoring, modeling and mitigating impacts of wind farms on local meteorology

    Science.gov (United States)

    Baidya Roy, Somnath; Traiteur, Justin; Kelley, Neil

    2010-05-01

    Wind power is one of the fastest growing sources of energy. Most of the growth is in the industrial sector comprising of large utility-scale wind farms. Recent modeling studies have suggested that such wind farms can significantly affect local and regional weather and climate. In this work, we present observational evidence of the impact of wind farms on near-surface air temperatures. Data from perhaps the only meteorological field campaign in an operational wind farm shows that downwind temperatures are lower during the daytime and higher at night compared to the upwind environment. Corresponding radiosonde profiles at the nearby Edwards Air Force Base WMO meteorological station show that the diurnal environment is unstable while the nocturnal environment is stable during the field campaign. This behavior is consistent with the hypothesis proposed by Baidya Roy et al. (JGR 2004) that states that turbulence generated in the wake of rotors enhance vertical mixing leading to a warming/cooling under positive/negative potential temperature lapse rates. We conducted a set of 306 simulations with the Regional Atmospheric Modeling System (RAMS) to test if regional climate models can capture the thermal effects of wind farms. We represented wind turbines with a subgrid parameterization that assumes rotors to be sinks of momentum and sources of turbulence. The simulated wind farms consistently generated a localized warming/cooling under positive/negative lapse rates as hypothesized. We found that these impacts are inversely correlated with background atmospheric boundary layer turbulence. Thus, if the background turbulence is high due to natural processes, the effects of additional turbulence generated by wind turbine rotors are likely to be small. We propose the following strategies to minimize impacts of wind farms: • Engineering solution: design rotors that generate less turbulence in their wakes. Sensitivity simulations show that these turbines also increase the

  18. Mobile measurement system for wind turbines

    Energy Technology Data Exchange (ETDEWEB)

    Kildemoes Moeller, T.

    1997-06-01

    The aim of this project `Udviklingsafproevning af smaa moellevinger` has been to develop a mobile measurement system for wind turbines. The following report describes the measurement system. The project has been financed by the Danish Ministry of Energy. (au)

  19. Initial results of local grid control using wind farms with grid support

    Energy Technology Data Exchange (ETDEWEB)

    Soerensen, Poul; Hansen, Anca D.; Iov, F.; Blaabjerg, F.

    2005-09-01

    This report describes initial results with simulation of local grid control using wind farms with grid support. The focus is on simulation of the behaviour of the wind farms when they are isolated from the main grid and establish a local grid together with a few other grid components. The isolated subsystems used in the work presented in this report do not intend to simulate a specific subsystem, but they are extremely simplified single bus bar systems using only a few more components than the wind farm. This approach has been applied to make it easier to understand the dynamics of the subsystem. The main observation is that the fast dynamics of the wind turbines seem to be able to contribute significantly to the grid control, which can be useful where the wind farm is isolated with a subsystem from the main grid with surplus of generation. Thus, the fast down regulation of the wind farm using automatic frequency control can keep the subsystem in operation and thereby improve the reliability of the grid. (LN)

  20. Introduction to wind energy systems

    Directory of Open Access Journals (Sweden)

    Wagner H.-J.

    2015-01-01

    Full Text Available This article presents the basic concepts of wind energy and deals with the physics and mechanics of operation. It describes the conversion of wind energy into rotation of turbine, and the critical parameters governing the efficiency of this conversion. After that it presents an overview of various parts and components of windmills. The connection to the electrical grid, the world status of wind energy use for electricity production, the cost situation and research and development needs are further aspects which will be considered.

  1. Solar wind control of the local time of substorm onset

    Science.gov (United States)

    Grocott, Adrian; Case, Nathan; Laundal, Karl; Laurens, Hannah; Milan, Steve

    2017-04-01

    We use solar wind and interplanetary magnetic field data, along with satellite global auroral imagery, to investigate what controls the magnetic local time (MLT) of substorm onset. We find that substorm onsets occur over a wide range of MLTs (18 - 4 hrs), with a typical MLT (mode) of 23 hrs. In agreement with previous studies, IMF BY , acts to move the onset to an earlier/later local time in the northern hemisphere and a later/earlier local time in the southern hemisphere, depending on the sign of BY , consistent with a twist of the conjugate magnetic field line. This effect explains a small fraction of the observed MLT variation (˜ 1 hr), but cannot account for the tendency of onset to be often displaced to earlier ( 23 hrs) MLTs in both hemispheres. We also inspect the relationship between solar wind V Y and onset MLT, which also has a small, but measurable effect on the local time of substorm onset. This effect acts in the same sense in the northern and southern hemispheres, moving onset to earlier times for positive V Y and later times for negative V Y . We find that a function relating both BY and V Y to onset MLT produces a better fit than a function based on either parameter alone.

  2. Control of a multivariable web winding system

    OpenAIRE

    N. RABBAH; B. BENSASSI

    2007-01-01

    To guarantee a good productivity and a better quality of the industrial systems, it is necessary to know the evolution of its various parameters but also its operation mode. The main goal of this work is to carry out a study to improve a flatness control in a reversing cold rolling mill, precisely the web winding system part. We designate by a winding process any system applying the cycles of unwinding, transport, treatment and winding to various flat products. This system knows several const...

  3. Wind energy systems: program summary

    Energy Technology Data Exchange (ETDEWEB)

    None

    1980-05-01

    The Federal Wind Energy Program (FWEP) was initiated to provide focus, direction and funds for the development of wind power. Each year a summary is prepared to provide the American public with an overview of government sponsored activities in the FWEP. This program summary describes each of the Department of Energy's (DOE) current wind energy projects initiated or renewed during FY 1979 (October 1, 1978 through September 30, 1979) and reflects their status as of April 30, 1980. The summary highlights on-going research, development and demonstration efforts and serves as a record of progress towards the program objectives. It also provides: the program's general management structure; review of last year's achievements; forecast of expected future trends; documentation of the projects conducted during FY 1979; and list of key wind energy publications.

  4. Wind energy systems: program summary

    Energy Technology Data Exchange (ETDEWEB)

    None

    1980-05-01

    The Federal Wind Energy Program (FWEP) was initiated to provide focus, direction and funds for the development of wind power. Each year a summary is prepared to provide the American public with an overview of government sponsored activities in the FWEP. This program summary describes each of the Department of Energy's (DOE) current wind energy projects initiated or renewed during FY 1979 (October 1, 1978 through September 30, 1979) and reflects their status as of April 30, 1980. The summary highlights on-going research, development and demonstration efforts and serves as a record of progress towards the program objectives. It also provides: the program's general management structure; review of last year's achievements; forecast of expected future trends; documentation of the projects conducted during FY 1979; and list of key wind energy publications.

  5. Small Wind Energy Systems for the Homeowner

    Energy Technology Data Exchange (ETDEWEB)

    None

    1997-01-01

    If you live in a rural or remote location, this publication will help you decide whether a wind system is practical for you. It explains the benefits, helps you assess your wind resource and possible sites, discusses legal and environmental obstacles, and analyzes economic considerations such as pricing.

  6. Long-distance transport of radioactive plume by nocturnal local winds

    Science.gov (United States)

    Yoshikane, Takao; Yoshimura, Kei; Chang, Eun-Chul; Saya, Akane; Oki, Taikan

    2016-11-01

    Radioactive plumes can spread far and wide depending on wind conditions. The plumes often frequently reached the Tokyo metropolitan area, which is approximately 200 km away from the Fukushima Daiichi nuclear power plant, under spatially heterogeneous wind fields in March 2011. To reduce exposure to radioactive plumes, the behaviour of the plumes must be known. However, the transport mechanism of radioactive plumes is not fully understood. Using a regional climate model, we show that multiple diurnal cycle processes play a key role in the frequent transport of radioactive plumes to the Tokyo metropolitan area. The observed data and hindcast results indicate that the radioactive plume moves along the local winds, which comprise the northeasterly local wind (NELW) associated with the meso-scale low-pressure system (meso-low) and the northerly sea wind (NSW) during the night. The long-term analysis and sensitivity simulations also show the nocturnal processes that the NELW caused by the meso-low and the NSW are formed east of the Tokyo metropolitan area and from Fukushima offshore east of the Tokyo metropolitan area, respectively, when neither winter monsoons nor extra-tropical cyclones are predominant. These findings indicate that the radioactive plumes could reach faraway places frequently via nocturnal local processes.

  7. Localized and systemic scleroderma.

    Science.gov (United States)

    Hawk, A; English, J C

    2001-03-01

    Scleroderma is a broad term encompassing both localized and systemic sclerosis. Localized scleroderma is a cutaneous limited fibrosis that manifests as plaque morphea, generalized morphea, linear scleroderma, and deep morphea. Systemic scleroderma (sclerosis) can manifest as either limited or diffuse disease. Limited systemic sclerosis is typically preceded by Raynaud's phenomenon, involves cutaneous sclerosis distal to the elbows, with gastrointestinal and pulmonary fibrosis, and anticentromere antibody positivity. Diffuse systemic scleroderma is characterized by simultaneous Raynaud's phenomenon, cutaneous skin involvement proximal to the elbow with gastrointestinal, pulmonary, renal and cardiac fibrosis, and positive serology for antitopoisomerase and anti-RNAP III antibodies. This article discusses the classification, epidemiology, pathogenesis, clinical manifestations, treatment, and prognosis of the scleroderma.

  8. Wind farm - A power source in future power systems

    DEFF Research Database (Denmark)

    Chen, Zhe; Blaabjerg, Frede

    2009-01-01

    wind turbines and wind farms, and then introduces the wind power development and wind farms. An optimization platform for designing electrical systems of offshore wind farms is briefed. The major issues related to the grid connection requirements and the operation of wind turbines/farms in power......The paper describes modern wind power systems, introduces the issues of large penetration of wind power into power systems, and discusses the possible methods of making wind turbines/farms act as a power source, like conventional power plants in power systems. Firstly, the paper describes modern...... systems are illustrated....

  9. 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...

  10. On System Identification of Wind Turbines

    DEFF Research Database (Denmark)

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

    . 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......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...

  11. Isolated systems with wind power. Main report

    DEFF Research Database (Denmark)

    Lundsager, P.; Bindner, Henrik W.; Clausen, Niels-Erik;

    2001-01-01

    approach for assessing the technical and economical feasibility of isolated power supply systems with wind energy. As a part of the project the following tasks were carried out: Review of literature, fieldmeasurements in Egypt, development of an inventory of small isolated systems, overview of end......The overall objective of this research project is to study the development of methods and guidelines rather than "universal solutions" for the use of wind energy in isolated communities. The main specific objective of the project is to develop and present amore unified and generally applicable...... for Isolated Systems with Wind Power, applicable for international organisations such as donoragencies and development banks....

  12. Distributed energy systems with wind power and energy storage

    Energy Technology Data Exchange (ETDEWEB)

    Korpaas, Magnus

    2004-07-01

    The topic of this thesis is the study of energy storage systems operating with wind power plants. The motivation for applying energy storage in this context is that wind power generation is intermittent and generally difficult to predict, and that good wind energy resources are often found in areas with limited grid capacity. Moreover, energy storage in the form of hydrogen makes it possible to provide clean fuel for transportation. The aim of this work has been to evaluate how local energy storage systems should be designed and operated in order to increase the penetration and value of wind power in the power system. Optimization models and sequential and probabilistic simulation models have been developed for this purpose. Chapter 3 presents a sequential simulation model of a general wind hydrogen energy system. Electrolytic hydrogen is used either as a fuel for transportation or for power generation in a stationary fuel cell. The model is useful for evaluating how hydrogen storage can increase the penetration of wind power in areas with limited or no transmission capacity to the main grid. The simulation model is combined with a cost model in order to study how component sizing and choice of operation strategy influence the performance and economics of the wind-hydrogen system. If the stored hydrogen is not used as a separate product, but merely as electrical energy storage, it should be evaluated against other and more energy efficient storage options such as pumped hydro and redox flow cells. A probabilistic model of a grid-connected wind power plant with a general energy storage unit is presented in chapter 4. The energy storage unit is applied for smoothing wind power fluctuations by providing a firm power output to the grid over a specific period. The method described in the chapter is based on the statistical properties of the wind speed and a general representation of the wind energy conversion system and the energy storage unit. This method allows us to

  13. The Etesian wind system and wind energy potential over the Aegean Sea

    Science.gov (United States)

    Dafka, Stella; Xoplaki, Elena; Garcia-Bustamante, Elena; Toreti, Andrea; Zanis, Prodromos; Luterbacher, Juerg

    2013-04-01

    The Mediterranean region lies in an area of great climatic interest since it is influenced by some of the most relevant mechanisms of the global climate system. In the frame of the three Europe 2020 priorities for a smart, sustainable and inclusive economy delivering high levels of employment, productivity and social cohesion, the Mediterranean energy plan is of paramount importance at the European level, being an area with a significant potential for renewable energy from natural sources that could play an important role in responding to climate change effects over the region. We present preliminary results on a study of the Etesian winds in the past, present and future time. We investigate the variability and predictability of the wind field over the Aegean. Statistical downscaling based on several methodologies will be applied (e.g. canonical correlation analysis and multiple linear regression). Instrumental time series, Era-Interim and the 20CR reanalyses will be used. Large-scale climate drivers as well as the influence of local/regional factors and their interaction with the Etesian wind field will be addressed. Finally, the Etesian wind resources on the present and future climate will be assessed in order to identify the potential areas suitable for the establishment of wind farms and the production of wind power in the Aegean Sea.

  14. Efficiency assessment of a wind pumping system

    Energy Technology Data Exchange (ETDEWEB)

    Lara, David D.; Merino, Gabriel G. [Department of Mechanization and Energy, University of Concepcion, Avenida Vicente Mendez 595, Chillan (Chile); Pavez, Boris J. [Department of Electrical Engineering, University of La Frontera, Casilla 54-D, Temuco (Chile); Tapia, Juan A. [Department of Electrical Engineering, University of Concepcion, Casilla 160-C, Concepcion (Chile)

    2011-02-15

    The combined efficiency of the components determines overall system performance in electric wind pumping systems. We evaluated a system composed of a 3 kW wind generator feeding a battery bank of 48 V/880 Ah by means of a non-controlled 6-pulse rectifier. Connected to this battery bank was a 1.5 kW inverter that generated 220 V at 50 Hz, which powers a 1.1 kW single-phase electric pump. At the University of Concepcion, Chile, energy losses in each electrical component was determined using a data collection system configured to measure electrical variables in real time. The electrical power generated by the wind generator for different wind speeds averaged 38% lower than the power curve provided by the manufacturer. Electromechanical tests performed in a lab showed the operation efficiency of the electric generator of the wind turbine averaged 80%. This information, along with the electrical power output, and the wind velocity measured during field operation allowed us to determine the rotor's power coefficient C{sub p}, which had a maximum value of 35%. For the stored energy components measured data indicated that the rectifier, the battery bank, and the inverter operated with average efficiencies of 95%, 78% and 86% respectively. The combined component efficiencies showed a maximum of 17% of the wind energy would be available for water pumping. Since a large amount of wind energy was dissipated during the energy conversion process, new configurations should be analyzed that could avoid such losses in wind pumping systems. (author)

  15. Offshore Wind Energy Systems Engineering Curriculum Development

    Energy Technology Data Exchange (ETDEWEB)

    McGowan, Jon G. [Univ. of Massachusetts, Amherst, MA (United States); Manwell, James F. [Univ. of Massachusetts, Amherst, MA (United States); Lackner, Matthew A. [Univ. of Massachusetts, Amherst, MA (United States)

    2012-12-31

    Utility-scale electricity produced from offshore wind farms has the potential to contribute significantly to the energy production of the United States. In order for the U.S. to rapidly develop these abundant resources, knowledgeable scientists and engineers with sound understanding of offshore wind energy systems are critical. This report summarizes the development of an upper-level engineering course in "Offshore Wind Energy Systems Engineering." This course is designed to provide students with a comprehensive knowledge of both the technical challenges of offshore wind energy and the practical regulatory, permitting, and planning aspects of developing offshore wind farms in the U.S. This course was offered on a pilot basis in 2011 at the University of Massachusetts and the National Renewable Energy Laboratory (NREL), TU Delft, and GL Garrad Hassan have reviewed its content. As summarized in this report, the course consists of 17 separate topic areas emphasizing appropriate engineering fundamentals as well as development, planning, and regulatory issues. In addition to the course summary, the report gives the details of a public Internet site where references and related course material can be obtained. This course will fill a pressing need for the education and training of the U.S. workforce in this critically important area. Fundamentally, this course will be unique due to two attributes: an emphasis on the engineering and technical aspects of offshore wind energy systems, and a focus on offshore wind energy issues specific to the United States.

  16. 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...... is based on available standard sensors on wind turbines. The method can be used both on-line as well as off-line. Faults or changes in the rotor system will result in asymmetries, which can be monitored and diagnosed. This can be done by using the multi-blade coordinate transformation. Changes in the rotor...... system that can be diagnosed and monitored are: actuator faults, sensor faults and internal blade changes as e.g. change in mass of a blade....

  17. Fluvial and glacial implications of tephra localities in the western Wind River basin, Wyoming, U. S. A

    Energy Technology Data Exchange (ETDEWEB)

    Jaworowski, C. (Univ. of Wyoming, Laramie, WY (United States). Dept. of Geology)

    1993-04-01

    Examination of Quaternary fluvial and glacial deposits in the western Wind River Basin allows a new understanding of the Quaternary Wind River fluvial system. Interbedded fluvial sediments and volcanic ashes provide important temporal information for correlation of Quaternary deposits. In the western Wind River Basin, six mid-Pleistocene localities of tephra, the Muddy Creek, Red Creek, Lander, Kinnear, Morton and Yellow Calf ashes are known. Geochronologic studies confirm the Muddy Creek, Red Creek, Kinnear and Lander ashes as the 620--650ka Lava Creek tephra from the Yellowstone region in northwestern Wyoming. The stratigraphic position and index of refraction of volcanic glass from the Morton and Yellow Calf ashes are consistent with identification as Lava Creek tephra. Approximately 350 feet (106 meters) above the Wind River and 13 miles downstream from Bull Lake, interbedded Wind River fluvial gravels, volcanic glass and pumice at the Morton locality correlate to late (upper) Sacajawea Ridge gravels mapped by Richmond and Murphy. Associated with the oxygen isotope 16--15 boundary, the ash-bearing terrace deposits reveal the nature of the Wind River fluvial system during late glacial-early interglacial times. The Lander and Yellow Calf ashes, are found in terrace deposits along tributaries of the Wind River. Differences in timing and rates of incision between the Wind River and its tributary, the Little Wind River, results in complex terrace development near their junction.

  18. Trends in Wind Turbine Generator Systems

    DEFF Research Database (Denmark)

    Polinder, Henk; Ferreira, Jan Abraham; Jensen, Bogi Bech;

    2013-01-01

    This paper reviews the trends in wind turbine generator systems. After discussing some important requirements and basic relations, it describes the currently used systems: the constant speed system with squirrel-cage induction generator, and the three variable speed systems with doubly fed...

  19. Local positioning system

    Energy Technology Data Exchange (ETDEWEB)

    Kyker, R.

    1995-07-25

    Navigation systems have been vital to transportation ever since man took to the air and sea. Early navigation systems utilized the sextant to navigate by starlight as well as the magnetic needle compass. As electronics and communication technologies improved, inertial navigation systems were developed for use in ships and missile delivery. These systems consisted of electronic compasses, gyro-compasses, accelerometers, and various other sensors. Recently, systems such as LORAN and the Global Positioning System (GPS) have utilized the properties of radio wave propagation to triangulate position. The Local Positioning System (LPS), described in this paper, is an implementation of a limited inertial navigation system designed to be used on a bicycle. LPS displays a cyclist`s current position relative to a starting location. This information is displayed in Cartesian-like coordinates. To accomplish this, LPS relies upon two sensors, an electronic compass sensor and a distance sensor. The compass sensor provides directional information while the distance sensor provides the distance traveled. This information yields a distance vector for each point in time which when summed produces the cyclist`s current position. LPS is microprocessor controlled and is designed for a range of less than 90 miles.

  20. Optimizing wind turbine control system parameters

    Energy Technology Data Exchange (ETDEWEB)

    Schluter, L.L. [Sandia National Labs., Albuquerque, NM (United States); Vachon, W.A. [Vachon (W.A.) and Associates, Inc., Manchester, MA (United States)

    1993-08-01

    The impending expiration of the levelized period in the Interim Standard Offer Number 4 (ISO4) utility contracts for purchasing wind-generated power in California mandates, more than ever, that windplants be operated in a cost-effective manner. Operating plans and approaches are needed that maximize the net revenue from wind parks--after accounting for operation and maintenance costs. This paper describes a design tool that makes it possible to tailor a control system of a wind turbine (WT) to maximize energy production while minimizing the financial consequences of fatigue damage to key structural components. Plans for code enhancements to include expert systems and fuzzy logic are discussed, and typical results are presented in which the code is applied to study the controls of a generic Danish 15-m horizontal axis wind turbine (HAWT).

  1. Changing local land systems

    DEFF Research Database (Denmark)

    Friis, Cecilie; Reenberg, Anette; Heinimann, Andreas

    2016-01-01

    This paper investigates the direct and cascading land system consequences of a Chinese company's land acquisition for rubber cultivation in northern Laos. Transnational land acquisitions are increasingly acknowledged as an important driver of direct land use conversion with implications for local....... Combining the conceptual lenses of land systems and livelihood approaches, this paper demonstrates how the land use system has changed substantially because of the establishment of the rubber plantation by the company, notably in the linkages between livestock rearing, upland shifting cultivation...... and lowland paddy rice cultivation. The changes go beyond the immediate competition for land caused by the rubber plantation: a penalty scheme introduced by the rubber company for damage to rubber trees caused by browsing animals has led the villagers to abandon livestock rearing, causing a cascade...

  2. Magnetorotationally driven wind cycles in local disc models

    Science.gov (United States)

    Riols, A.; Ogilvie, G. I.; Latter, H.; Ross, J. P.

    2016-12-01

    Jets, from the protostellar to the AGN context, have been extensively studied but their connection to the turbulent dynamics of the underlying accretion disc is poorly understood. Following a similar approach to Lesur, Fereira & Ogilvie, we examine the role of the magnetorotational instability (MRI) in the production and acceleration of outflows from discs. Via a suite of 1D shearing-box simulations of stratified discs, we show that magnetocentrifugal winds exhibit cyclic activity with a period of 10-20 Ω-1, a few times the orbital period. The cycle seems to be more vigorous for strong vertical field; it is robust to the variation of relevant parameters and independent of numerical details. The convergence of these solutions (in particular the mass-loss rate) with vertical box size is also studied. By considering a sequence of magnetohydrostatic equilibria and their stability, the periodic activity may be understood as the succession of the following phases: (a) a dominant MRI channel mode, (b) strong magnetic field generation, (c) consequent wind launching, and ultimately (d) vertical expulsion of the excess magnetic field by the expanding and accelerating gas associated with the wind. We discuss potential connections between this behaviour and observed time-variability in disc-jet systems.

  3. McCabe wind energy system

    Energy Technology Data Exchange (ETDEWEB)

    Norton, R. [Wyndmoor (United States); McCabe, F. [Levr/Air, Inc., Doylestown (United States); MacMichael, G. [Regional Technical College, Galway (Iran, Islamic Republic of)

    1995-12-31

    A wind machine utilizing novel low-speed air foils and shrouds has been developed and is now undergoing a refinement process. Energy generated by the machine at a variety of wind speeds is significant. Use of the machine to compress air, which can serve a variety of applications, simplifies the total power producing system ranking it economical and practical for use at a variety of locations to fill many energy requirements. (author)

  4. 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).

  5. Some results concerning no-storage wind-diesel systems control

    Directory of Open Access Journals (Sweden)

    Ciprian VLAD

    2006-12-01

    Full Text Available This paper deal with the dynamics of an autonomous no storage wind-diesel system, comprising a diesel generator and a controlled wind system with a hypo/hyper synchronous cascade. The objective is to maximize the wind energy penetration rate, by an optimization control system, respecting the quality standard concerning the frequency deviation in the AC local grid. Also, the influence of the diesel drive train on the system’s dynamics performances is discussed.

  6. An approach to determining the local boundaries of voltage stability region with wind farms in power injection space

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    A new approach to determining the local boundaries of voltage stability region in power injection space (IVSR) for power system with wind farms is presented. It can be used for power system voltage stability analysis and on-line security assessment with considering the output uncertainty of the wind farms. Firstly, power flow tracing and double dispatching are used to determine the generators that are closely related to the wind farms, in order to balance the power fluctuations caused by the wind speed variation. Then, modal analysis is used to get the key generators to achieve an effective dimension reduction for IVSR. Finally, the forecasting output power (or wind speed) of wind farms is divided into several intervals. For each interval, the corresponding local IVSR boundaries can be calculated by the method based on small disturbance. Moreover, parallel process is used to accelerate the computing speed. The presented approach is validated by several power systems. It can be revealed that the approach can give the local IVSR boundaries at different wind speeds and has a good engineering application prospect.

  7. Automated wind-icing monitoring system

    Energy Technology Data Exchange (ETDEWEB)

    Horokhov, Y.; Nekrasov, Y.; Turbin, S. [Donbas National Academy of Civil Engineering and Architecture, Makeyevka, Donetsk (Ukraine); Grimud, G. [NEC Ukrenergo, Kiev (Ukraine)

    2005-07-01

    The development of automated wind-icing monitoring systems (AWIMS) has increased the operational reliability of existing overhead lines through a more accurate prediction of icing events in the Ukraine. The systems are capable of operating without the presence of personnel, and allow operators to immediately obtain information about icing processes. The systems provide statistically significant sets of data for determining and predicting loading conditions, as well as combining measurements of icing mass, wind speed and direction, temperature and humidity. An outline of the principles of AWIMS was presented in paper, as well as a description of the system's architecture and operating principles. The monitoring system consists of an ice mass measuring device; a strain gauge sensor; a photoelectric pickup to determine perpendicular mean wind direction; and a wire simulator. The measuring devices are installed 10 meters above ground. Data is transmitted every 30 minutes to a central information office, where information is processed and stored. Details of the ultrasonic anemometer for wind measurements as well as the devices used for humidity and temperature measurement were presented. The AWIMS computer software measures 6 climatic parameters: wind speed; wind direction; air temperature; humidity; icing mass; and wind pressure on ice-covered wires. Results of a series of tests were presented which included a weather station data analysis and a comparison of the AWIMS with standard climatic loads. An analysis of overhead line failure statistical data was also conducted. Spatial icing distributions were used to calculate the threshold sensitivity for the AWIMS. As estimation of overhead lines density per square kilometer showed was made to determine placement of the systems. It was concluded that 8 more AWIMS will be installed in the following year. 3 refs., 10 figs.

  8. Combined Solar and Wind Energy Systems

    Science.gov (United States)

    Tripanagnostopoulos, Y.; Souliotis, M.; Makris, Th.

    2010-01-01

    In this paper we present the new concept of combined solar and wind energy systems for buildings applications. Photovoltaics (PV) and small wind turbines (WTs) can be install on buildings, in case of sufficient wind potential, providing the building with electricity. PVs can be combined with thermal collectors to form the hybrid photovoltaic/thermal (PV/T) systems. The PVs (or the PV/Ts) and WT subsystems can supplement each other to cover building electrical load. In case of using PV/T collectors, the surplus of electricity, if not used or stored in batteries, can increase the temperature of the thermal storage tank of the solar thermal unit. The description of the experimental set-up of the suggested PV/T/WT system and experimental results are presented. In PV/T/WT systems the output from the solar part depends on the sunshine time and the output of the wind turbine part depends on the wind speed and is obtained any time of day or night. The use of the three subsystems can cover a great part of building energy load, contributing to conventional energy saving and environment protection. The PV/T/WT systems are considered suitable in rural and remote areas with electricity supply from stand-alone units or mini-grid connection. PV/T/WT systems can also be used in typical grid connected applications.

  9. Hydraulic Soft Yaw System for Multi MW Wind Turbines

    DEFF Research Database (Denmark)

    Stubkier, Søren

    Horizontal axis wind turbines utilize a yaw system to keep the rotor plane of the wind turbine perpendicular to the main wind direction. If the wind direction changes, the wind turbine follows the direction change by yawing. If the wind turbine does not yaw, there will be a reduction in produced...... of nine concepts for hydraulic yaw systems and shown that the loading of the turbine structure may be damped if the yaw system is allowed to deflect under loading. An extensions of the open source wind turbine code FAST of a state of the art wind turbine including the yaw degree of freedom and friction...

  10. A Critique of `Trees as a Local Climatic Wind Indicator'.

    Science.gov (United States)

    Hennessey, Joseph P., Jr.

    1980-08-01

    This comment reviews many of the problems associated with using deformed vegetation as an indicator of mean annual wind speed and wind power potential. It critiques the Wade and Hewson (1979) use of a `jackknife technique' to estimate prediction errors for mean annual wind speeds and presents a reanalysis of the data. It is concluded that the available evidence still suggests that wind deformed trees will prove to be unreliable as well as imprecise estimators of either mean annual wind speeds or more complicated quantities such as wind power potential.

  11. Power Electronics in Wind Turbine Systems

    DEFF Research Database (Denmark)

    Blaabjerg, Frede; Chen, Zhe; Teodorescu, Remus

    2006-01-01

    the conventional, fossil (and short term) based energy sources to renewable energy resources. The other is to use high efficient power electronics in power systems, power production and end-user application. This paper discuss the most emerging renewable energy source, wind energy, which by means of power...... electronics is changing from being a minor energy source to be acting as an important power source in the energy system. By that wind power is also getting an added value in the power system operation....

  12. 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...

  13. A review of large wind turbine systems

    Science.gov (United States)

    Selzer, H.; Lerner, J. I.

    Research areas in the design and operation of large wind turbines in the U.S. and Europe are detailed, with attention given to current and completed programs. Theoretical work in the U.S. is focused on aerodynamics of blades, structural dynamics, control systems, and safety through safe life design, redundancy, and quality assurance. Work is continuing on wind characteristics over the rotor disk and design criteria with regard to cost/benefits and tradeoffs involving various configurations and materials for the rotor blades, placement, pitch control, blade articulation, the tower, the drive train, the gear box, a quill shaft, generator type, and reliability and maintenance. Costing models are being developed. Test experience has been gained through the manufacture and operation of the five Mod 0A, one Mod-1, four Mod-2, and one WTS-4 wind turbines. The European work on blade loading, wind turbine dimensioning, materials, wind structure, environmental impacts, and economics are reviewed, together with the operational experience with the Gedser, two Nibe, the Tvind, and Growian machines. Several countries are also testing smaller wind turbines manufactured indigenously or imported.

  14. Wind power integration connection and system operational aspects

    CERN Document Server

    Fox, Brendan

    2014-01-01

    Wind Power Integration provides a wide-ranging discussion on all major aspects of wind power integration into electricity supply systems. This second edition has been fully revised and updated to take account of the significant growth in wind power deployment in the past few years. New discussions have been added to describe developments in wind turbine generator technology and control, the network integration of wind power, innovative ways to integrate wind power when its generation potential exceeds 50% of demand, case studies on how forecasting errors have affected system operation, and an update on how the wind energy sector has fared in the marketplace. Topics covered include: the development of wind power technology and its world-wide deployment; wind power technology and the interaction of various wind turbine generator types with the utility network; and wind power forecasting and the challenges faced by wind energy in modern electricity markets.

  15. Synchronous generator wind energy conversion control system

    Energy Technology Data Exchange (ETDEWEB)

    Medeiros, A.L.R. [Wind Energy Group, Recife (Brazil); Lima, A.M.N.; Jacobina, C.B.; Simoes, F.J. [DEE, Campina Grande (Brazil)

    1996-12-31

    This paper presents the performance evaluation and the design of the control system of a WECS (Wind Energy Conversion System) that employs a synchronous generator based on its digital simulation. The WECS discussed in this paper is connected to the utility grid through two Pulse Width Modulated (PWM) power converters. The structure of the proposed WECS enables us to achieve high performance energy conversion by: (i) maximizing the wind energy capture and (ii) minimizing the reactive power flowing between the grid and the synchronous generator. 8 refs., 19 figs.

  16. Wind loads on solar energy systems, mounted on flat roofs

    NARCIS (Netherlands)

    Geurts, C.P.W.; Bentum, C.A. van; Blackmore, P.

    2005-01-01

    Wind loads on solar energy systems are not covered by current wind loading standards. This paper describes results of a parametric study into the wind loads on solar energy systems, which are placed on flat roofs. Wind tunnel measurements have been carried out on a number of configurations. The resu

  17. Wind Farms’ Spatial Distribution Effect on Power System Reserves Requirements

    DEFF Research Database (Denmark)

    Sørensen, Poul Ejnar; Cutululis, Nicolaos Antonio

    2010-01-01

    in smaller areas, which causes the total wind power fluctuations in power system areas to increase significantly. The impact of future large wind farms spatial distribution with respect to the power system reserve requirements is analyzed in this paper. For this purpose, Correlated Wind (CorWind) power time...

  18. Wind loads on solar energy systems, mounted on flat roofs

    NARCIS (Netherlands)

    Geurts, C.P.W.; Bentum, C.A. van; Blackmore, P.

    2005-01-01

    Wind loads on solar energy systems are not covered by current wind loading standards. This paper describes results of a parametric study into the wind loads on solar energy systems, which are placed on flat roofs. Wind tunnel measurements have been carried out on a number of configurations. The resu

  19. Dynamic influences of wind power on the power system

    Energy Technology Data Exchange (ETDEWEB)

    Rosas, Pedro

    2003-03-01

    The thesis first presents the basics influences of wind power on the power system stability and quality by pointing out the main power quality issues of wind power in a small-scale case and following, the expected large-scale problems are introduced. Secondly, a dynamic wind turbine model that supports power quality assessment of wind turbines is presented. Thirdly, an aggregate wind farm model that support power quality and stability analysis from large wind farms is presented. The aggregate wind farm model includes the smoothing of the relative power fluctuation from a wind farm compared to a single wind turbine. Finally, applications of the aggregate wind farm model to the power systems are presented. The power quality and stability characteristics influenced by large-scale wind power are illustrated with three cases. In this thesis, special emphasis has been given to appropriate models to represent the wind acting on wind farms. The wind speed model to a single wind turbine includes turbulence and tower shadow effects from the wind and the rotational sampling turbulence due to the rotation of the blades. In a park scale, the wind speed model to the wind farm includes the spatial coherence between different wind turbines. Here the wind speed model is applied to a constant rotational speed wind turbine/farm, but the model is suitable to variable speed wind turbine/farm as well. The cases presented here illustrate the influences of the wind power on the power system quality and stability. The flicker and frequency deviations are the main power quality parameters presented. The power system stability concentrates on the voltage stability and on the power system oscillations. From the cases studied, voltage and the frequency variations were smaller than expected from the large-scale wind power integration due to the low spatial correlation of the wind speed. The voltage quality analysed in a Brazilian power system and in the Nordel power system from connecting large

  20. A new wind energy conversion system

    Science.gov (United States)

    Smetana, F. O.

    1975-01-01

    It is presupposed that vertical axis wind energy machines will be superior to horizontal axis machines on a power output/cost basis and the design of a new wind energy machine is presented. The design employs conical cones with sharp lips and smooth surfaces to promote maximum drag and minimize skin friction. The cones are mounted on a vertical axis in such a way as to assist torque development. Storing wind energy as compressed air is thought to be optimal and reasons are: (1) the efficiency of compression is fairly high compared to the conversion of mechanical energy to electrical energy in storage batteries; (2) the release of stored energy through an air motor has high efficiency; and (3) design, construction, and maintenance of an all-mechanical system is usually simpler than for a mechanical to electrical conversion system.

  1. A new wind energy conversion system

    Energy Technology Data Exchange (ETDEWEB)

    Smetana, F.O.

    1975-11-01

    It is presupposed that vertical axis wind energy machines will be superior to horizontal axis machines on a power output/cost basis and the design of a new wind energy machine is presented. The design employs conical cones with sharp lips and smooth surfaces to promote maximum drag and minimize skin friction. The cones are mounted on a vertical axis in such a way as to assist torque development. Storing wind energy as compressed air is thought to be optimal and reasons are: (1) the efficiency of compression is fairly high compared to the conversion of mechanical energy to electrical energy in storage batteries; (2) the release of stored energy through an air motor has high efficiency; and (3) design, construction, and maintenance of an all-mechanical system is usually simpler than for a mechanical to electrical conversion system. (GRA)

  2. Structural Health Monitoring of Wind Turbine Blades: Acoustic Source Localization Using Wireless Sensor Networks

    Directory of Open Access Journals (Sweden)

    Omar Mabrok Bouzid

    2015-01-01

    Full Text Available Structural health monitoring (SHM is important for reducing the maintenance and operation cost of safety-critical components and systems in offshore wind turbines. This paper proposes an in situ wireless SHM system based on an acoustic emission (AE technique. By using this technique a number of challenges are introduced due to high sampling rate requirements, limitations in the communication bandwidth, memory space, and power resources. To overcome these challenges, this paper focused on two elements: (1 the use of an in situ wireless SHM technique in conjunction with the utilization of low sampling rates; (2 localization of acoustic sources which could emulate impact damage or audible cracks caused by different objects, such as tools, bird strikes, or strong hail, all of which represent abrupt AE events and could affect the structural health of a monitored wind turbine blade. The localization process is performed using features extracted from aliased AE signals based on a developed constraint localization model. To validate the performance of these elements, the proposed system was tested by testing the localization of the emulated AE sources acquired in the field.

  3. Control of a multivariable web winding system

    Directory of Open Access Journals (Sweden)

    N. RABBAH

    2007-12-01

    Full Text Available To guarantee a good productivity and a better quality of the industrial systems, it is necessary to know the evolution of its various parameters but also its operation mode. The main goal of this work is to carry out a study to improve a flatness control in a reversing cold rolling mill, precisely the web winding system part. We designate by a winding process any system applying the cycles of unwinding, transport, treatment and winding to various flat products. This system knows several constraints such as the thermal effects caused by the frictions, and the mechanical effects provoked by metal elongation, that generates dysfunctions due to the influence of the process conditions. For this installations type, the various automatisms functions, often very advanced, are realized in modular systems with distributed architecture. Our main goal is to obtain a precise thickness, with the best possible regularity. With this intention, we are preceded to the modelling and the control of the nonlinear dynamic behaviour of a web winding process.

  4. Incentives and barriers for wind power expansion and system integration in Denmark

    DEFF Research Database (Denmark)

    Hvelplund, Frede; Ostergaard, Poul Alberg; Meyer, Niels I

    2017-01-01

    In Denmark expansion of on-shore, near-shore and off-shore wind power is planned to increase the wind power share to 50% of electricity consumption by 2020. In this situation a continuation of past policies will not suffice, and a dual-track incentive system that both establishes incentives......-shore and near-shore wind power expansion is a growing citizens' resistance due to an unequal distribution of benefits and burdens. Ownership should be open for more types of investors especially local investors in order to ensure public support and local acceptance of wind power projects. The Danish political...

  5. Aeroelastic analysis of wind energy conversion systems

    Science.gov (United States)

    Dugundji, J.

    1978-01-01

    An aeroelastic investigation of horizontal axis wind turbines is described. The study is divided into two simpler areas; (1) the aeroelastic stability of a single blade on a rigid tower; and (2) the mechanical vibrations of the rotor system on a flexible tower. Some resulting instabilities and forced vibration behavior are described.

  6. A High Efficiency Wind Energy System

    DEFF Research Database (Denmark)

    Khan, M. Z.; Hussain, M. M.; Naveed, M. M.;

    2012-01-01

    In this paper, a wind generator system that employs a Fourphase Interleaved Bi-directional DC / DC Converter, a Selective Harmonic Elimination Sinusoidal Pulse Width Modulation (SHE SPWM) based Inverter and a PermanentMagnet Synchronous Generator (PMSG) is studied. The merits of using the topolog...

  7. Vestas Wind Systems A/S

    OpenAIRE

    2009-01-01

    Much had happened since the CEO of Vestas Wind Systems A/S, Ditlev Engel, broadcast the company’s new corporate strategy – The Will to Win 2005-2008 – from headquarters in Randers, Denmark to all Vestas employees worldwide in 2005. Vestas, the market-leading producer of high-tech wind turbines, had since a merger the year before with a Danish turbine producer experienced financial difficulties, and management was therefore replaced with fresh leadership that could bring the Dan...

  8. Cooperative field test program for wind systems

    Energy Technology Data Exchange (ETDEWEB)

    Bollmeier, W.S. II; Dodge, D.M.

    1992-03-01

    The objectives of the Federal Wind Energy Program, managed by the US Department of Energy (DOE), are (1) to assist industry and utilities in achieving a multi-regional US market penetration of wind systems, and (2) to establish the United States as the world leader in the development of advanced wind turbine technology. In 1984, the program conducted a series of planning workshops with representatives from the wind energy industry to obtain input on the Five-Year Research Plan then being prepared by DOE. One specific suggestion that came out of these meetings was that the federal program should conduct cooperative research tests with industry to enhance the technology transfer process. It was also felt that the active involvement of industry in DOE-funded research would improve the state of the art of wind turbine technology. DOE established the Cooperative Field Test Program (CFTP) in response to that suggestion. This program was one of the first in DOE to feature joint industry-government research test teams working toward common objectives.

  9. 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.

  10. System Reliability for Offshore Wind Turbines

    DEFF Research Database (Denmark)

    Marquez-Dominguez, Sergio; Sørensen, John Dalsgaard

    2013-01-01

    are considered for reliability verification according to international design standards of OWTs. System effects become important for each substructure with many potential fatigue hot spots. Therefore, in this paper a framework for system effects is presented. This information can be e.g. no detection of cracks......E). In consequence, a rational treatment of uncertainties is done in order to assess the reliability of critical details in OWTs. Limit state equations are formulated for fatigue critical details which are not influenced by wake effects generated in offshore wind farms. Furthermore, typical bi-linear S-N curves...... 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....

  11. Laboratory Simulations of Local Winds in the Atmospheric Boundary Layer via Image Analysis

    Directory of Open Access Journals (Sweden)

    Monica Moroni

    2015-01-01

    Full Text Available In the atmospheric boundary layer, under high pressure conditions and negligible geostrophic winds, problems associated with pollution are the most critical. In this situation local winds play a major role in the evaluation of the atmospheric dynamics at small scales and in dispersion processes. These winds originate as a result of nonuniform heating of the soil, either when it is homogeneous or in discontinuous terrain in the presence of sea and/or slopes. Depending on the source of the thermal gradient, local winds are classified into convective boundary layer, sea and land breezes, urban heat islands, and slope currents. Local winds have been analyzed by (i simple analytical models; (ii numerical models; (iii field measurements; (iv laboratory measurements through which it is impossible to completely create the necessary similarities, but the parameters that determine the phenomenon can be controlled and each single wind can be separately analyzed. The present paper presents a summary of laboratory simulations of local winds neglecting synoptic winds and the effects of Coriolis force. Image analysis techniques appear suitable to fully describe both the individual phenomenon and the superposition of more than one local wind. Results do agree with other laboratory studies and numerical experiments.

  12. Local acceptance of wind energy. A comparison between Germany, Argentina and Spain

    Energy Technology Data Exchange (ETDEWEB)

    Jimeno, Moira [Freie Univ. Berlin (DE). Forschungszentrum fuer Umweltpolitik (ffu)

    2011-07-01

    Commercial exploitation of wind parks started in the early 1990s in Germany, and in the mid 1990s in Spain and Argentina. Then, there have been an incremental use of wind turbines in rural areas. Many of them are characterised in economic terms by a diversified economic structure with a marginal significance. In the ''innovative democracy and concrete institutional economy'' approach one of the key problems regarding wind turbines, is the local acceptance. This raises the following questions: how is local acceptance, from the perspective of the innovative democracy, of the wind regions in Germany and Spain and why it was developed in this way. Another central question concerning the local acceptance of wind energy is how wind regions in Argentina (as an example of an emerging country investing in renewable energy) can learn from the European experiences. Based on this, I would like to make a comparative analysis between Germany, Spain and Argentina on the basis of various regions with the corresponding wind parks, within regional differences and similarities are to be worked out. First results tend to demonstrate that wind energy promotion programs will be most successful (in terms of their higher level of social acceptance) in locales that have participatory decision making structures and incorporate wind energy development into broader local or regional development programs. For example in touristic programs. In order to verify this the case study approach is focused on comparing selected regions based on the three countries. (orig.)

  13. Integrated energy systems and local energy markets

    DEFF Research Database (Denmark)

    Lund, Henrik; Münster, Ebbe

    2006-01-01

    Significant benefits are connected with an increase in the flexibility of the Danish energy system. On the one hand, it is possible to benefit from trading electricity with neighbouring countries, and on the other, Denmark will be able to make better use of wind power and other types of renewable...... energy in the future. This paper presents the analysis of different ways of increasing flexibility in the Danish energy system by the use of local regulation mechanisms. This strategy is compared with the opposite extreme, i.e. trying to solve all balancing problems via electricity trade...

  14. 76 FR 76333 - Notification for Airborne Wind Energy Systems (AWES)

    Science.gov (United States)

    2011-12-07

    ... Federal Aviation Administration 14 CFR Part 77 Notification for Airborne Wind Energy Systems (AWES) AGENCY...,'' to airborne wind energy systems (AWES). In addition, this notice requests information from airborne wind energy system developers and the public related to these systems so that the FAA...

  15. A Vision for Systems Engineering Applied to Wind Energy (Presentation)

    Energy Technology Data Exchange (ETDEWEB)

    Felker, F.; Dykes, K.

    2015-01-01

    This presentation was given at the Third Wind Energy Systems Engineering Workshop on January 14, 2015. Topics covered include the importance of systems engineering, a vision for systems engineering as applied to wind energy, and application of systems engineering approaches to wind energy research and development.

  16. Prognosticating fault development rate in wind turbine generator bearings using local trend models

    DEFF Research Database (Denmark)

    Skrimpas, Georgios Alexandros; Palou, Jonel; Sweeney, Christian Walsted;

    2016-01-01

    Generator bearing defects, e.g. ball, inner and outer race defects, are ranked among the most frequent mechanical failures encountered in wind turbines. Diagnosis and prognosis of bearing faults can be successfully implemented using vibration based condition monitoring systems, where tracking...... the signal energy between 10Hz to 1000Hz is utilized as feature to characterize the severity of developing bearing faults. Furthermore, local trend models are employed to predict the progression of bearing defects from a vibration standpoint in accordance with the limits suggested in ISO 10816. Predictions...... of vibration trends from multi-megawatt wind turbine generators are presented, showing the effectiveness of the suggested approach on the calculation of the RUL and fault progression rate....

  17. Intelligent non-linear modelling of an industrial winding process using recurrent local linear neuro-fuzzy networks

    Institute of Scientific and Technical Information of China (English)

    Hasan ABBASI NOZARI; Hamed DEHGHAN BANADAKI; Mohammad MOKHTARE; Somaveh HEKMATI VAHED

    2012-01-01

    This study deals with the neuro-fuzzy (NF) modelling of a real industrial winding process in which the acquired NF model can be exploited to improve control performance and achieve a robust fault-tolerant system.A new simulator model is proposed for a winding process using non-linear identification based on a recurrent local linear neuro-fuzzy (RLLNF) network trained by local linear model tree (LOLIMOT),which is an incremental tree-based learning algorithm.The proposed NF models are compared with other known intelligent identifiers,namely multilayer perceptron (MLP) and radial basis function (RBF).Comparison of our proposed non-linear models and associated models obtained through the least square error (LSE) technique (the optimal modelling method for linear systems) confirms that the winding process is a non-linear system.Experimental results show the effectiveness of our proposed NF modelling approach.

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

    DEFF Research Database (Denmark)

    Barahona Garzón, Braulio

    conditions that stem from disturbances in the power system. An integrated simulation environment, wind turbine models, and power system models are developed in order to take an integral perspective that considers the most important aeroelastic, structural, electrical, and control dynamics. Applications...... system frequency control studies of variable-speed wind turbines with the integrated simulation environment, show that is possible to make a sensible estimation of the contribution of a wind farm to power system frequency control, while studying the impact on wind turbine structural loads. Finally......Megawatt-size wind turbines nowadays operate in very complex environmental conditions, and increasingly demanding power system requirements. Pursuing a cost-effective and reliable wind turbine design is a multidisciplinary task. However nowadays, wind turbine design and research areas...

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2017-08-14

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

  20. An Integrated Framework of Drivetrain Degradation Assessment and Fault Localization for Offshore Wind Turbines

    Directory of Open Access Journals (Sweden)

    Jay Lee

    2013-01-01

    Full Text Available As wind energy proliferates in onshore and offshore applications, it has become significantly important to predict wind turbine downtime and maintain operation uptime to ensure maximal yield. Two types of data systems have been widely adopted for monitoring turbine health condition: supervisory control and data acquisition (SCADA and condition monitoring system (CMS. Provided that research and development have focused on advancing analytical techniques based on these systems independently, an intelligent model that associates information from both systems is necessary and beneficial. In this paper, a systematic framework is designed to integrate CMS and SCADA data and assess drivetrain degradation over its lifecycle. Information reference and advanced feature extraction techniques are employed to procure heterogeneous health indicators. A pattern recognition algorithm is used to model baseline behavior and measure deviation of current behavior, where a Self-organizing Map (SOM and minimum quantization error (MQE method is selected to achieve degradation assessment. Eventually, the computation and ranking of component contribution to the detected degradation offers component-level fault localization. When validated and automated by various applications, the approach is able to incorporate diverse data resources and output actionable information to advise predictive maintenance with precise fault information. The approach is validated on a 3 MW offshore turbine, where an incipient fault is detected well before existing system shuts down the unit. A radar chart is used to illustrate the fault localization result.

  1. Dynamic Influences of Wind Power on The Power System

    DEFF Research Database (Denmark)

    Rosas, Pedro Andrè Carvalho

    2004-01-01

    The thesis first presents the basic influences of wind power on the power system stability and quality by pointing out the main power quality issues of wind power in a small-scale case and following, the expected large-scale problems are introduced.Secondly, a dynamic wind turbine model...... to a single wind turbine. Finally, applications of the aggregate wind farm model to the power systems are presented. The power quality and stabilitycharacteristics influenced by large-scale wind power are illustrated with three cases. In this thesis, special emphasis has been given to appropriate models...... that supports power quality assessment of wind turbines is presented. Thirdly, an aggregate wind farm model that support power quality and stability analysis from large wind farms is presented. The aggregate windfarm model includes the smoothing of the relative power fluctuation from a wind farm compared...

  2. Intention to respond to local wind turbines: the role of attitudes and visual perception

    Energy Technology Data Exchange (ETDEWEB)

    Johansson, Maria; Laike, Thorbjorn [Environmental Psychology Unit, Department of Architecture and the Built Environment, Lund University, PO Box 118, SE-221 00 Lund, (Sweden)

    2007-06-21

    Wind power projects frequently face public opposition during the siting process. A deeper understanding of social factors has therefore been called for. Based on psychological theories, the present research was initiated in order to study the relative importance of individual aspects related to visual perception and attitudinal factors in public intention to oppose local wind turbines. In an empirical study, 80 people assessed the visual characteristics of wind turbines on site and rated their emotional state. They also completed a questionnaire covering attitudes towards the turbines, perception of significant others' opinions of local wind turbines, and perceived possibilities to oppose as well as intention to oppose local turbines. Moreover, socio-demographics, factors related to the place of residence and general attitude towards wind power, were investigated. In a multiple regression analysis explaining 50% of the variance, it was found that intention to oppose was related to only a few perceptual and attitudinal factors, i.e. the perceived unity of the environment, the personal attitude towards the effects of wind turbines on landscape aesthetics and recreation, and the general attitude towards wind power. Of minor importance was the attitude towards the effects of wind turbines on people's daily quality of life. It seems important to involve the public in the discussion of how wind power installations can be integrated into the landscape without threatening the visual beauty and the recreational value of the natural and cultural environment. Moreover, social intervention is required to promote positive attitudes towards wind turbines. (Author).

  3. 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.

  4. 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.

  5. Wind Sensorless Control of Wind Energy Conversion System with PMS Generator

    OpenAIRE

    El Magri, Abdelmounime; Giri, Fouad; Elfadili, Abderrahim; Dugard, Luc

    2012-01-01

    6 pages; International audience; This paper addresses the problem of controlling wind energy conversion systems (WECS) which involve permanent magnet synchronous generator (PMSG) fed by IGBT-based buck-to-buck rectifier-inverter. The goal of control is to maximize wind energy extraction and this needs letting the wind turbine rotor operate in variable-speed mode. Interestingly, the present study features the achievement of the above energetic goal without resorting to sensors for wind velocit...

  6. Comprehensive Measurements of Wind Systems at the Dead Sea

    Science.gov (United States)

    Metzger, Jutta; Corsmeier, Ulrich; Kalthoff, Norbert; Wieser, Andreas; Alpert, Pinhas; Lati, Joseph

    2016-04-01

    The Dead Sea is a unique place on earth. It is located at the lowest point of the Jordan Rift valley and its water level is currently at -429 m above mean sea level (amsl). To the West the Judean Mountains (up to 1000 m amsl) and to the East the Moab mountains (up to 1300 m amsl) confine the north-south oriented valley. The whole region is located in a transition zone of semi-arid to arid climate conditions and together with the steep orography, this forms a quite complex and unique environment. The Virtual Institute DEad SEa Research Venue (DESERVE) is an international project funded by the German Helmholtz Association and was established to study coupled atmospheric, hydrological, and lithospheric processes in the changing environment of the Dead Sea. Previous studies showed that the valley's atmosphere is often governed by periodic wind systems (Bitan, 1974), but most of the studies were limited to ground measurements and could therefore not resolve the three dimensional development and evolution of these wind systems. Performed airborne measurements found three distinct layers above the Dead Sea (Levin, 2005). Two layers are directly affected by the Dead Sea and the third is the commonly observed marine boundary layer over Israel. In the framework of DESERVE a field campaign with the mobile observatory KITcube was conducted to study the three dimensional structure of atmospheric processes at the Dead Sea in 2014. The combination of several in-situ and remote sensing instruments allows temporally and spatially high-resolution measurements in an atmospheric volume of about 10x10x10 km3. With this data set, the development and evolution of typical local wind systems, as well as the impact of regional scale wind conditions on the valley's atmosphere could be analyzed. The frequent development of a nocturnal drainage flow with wind velocities of over 10 m s-1, the typical lake breeze during the day, its onset and vertical extension as well as strong downslope winds

  7. Isolated systems with wind power. Main report

    Energy Technology Data Exchange (ETDEWEB)

    Lundsager, P.; Bindner, H.; Clausen, N.E.; Frandsen, S.; Hansen, L.H.; Hansen, J.C.

    2001-06-01

    The overall objective of this research project is to study the development of methods and guidelines rather than 'universal solutions' for the use of wind energy in isolated communities. The main specific objective of the project is to develop and present a more unified and generally applicable approach for assessing the technical and economical feasibility of isolated power supply systems with wind energy. As a part of the project the following tasks were carried out: Review of literature, field measurements in Egypt, development of an inventory of small isolated systems, overview of end-user demands, analysis of findings and development of proposed guidelines. The project is reported in one main report and four topical reports, all of them issued as Risoe reports. This is the Main Report Risoe-R-1256, summing up the activities and findings of the project and outlining an Implementation Strategy for Isolated Systems with Wind Power, applicable for international organisations such as donor agencies and development banks. (au)

  8. Design of Wind Turbine Vibration Monitoring System

    National Research Council Canada - National Science Library

    Shoubin Wang; Wei Gong; Gang Su; Hongyue Sun

    2013-01-01

    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...

  9. Wind energy systems solutions for power quality and stabilization

    CERN Document Server

    Ali, Mohd Hasan

    2012-01-01

    Unlike conventional power plants, wind plants emit no air pollutants or greenhouse gases--and wind energy is a free, renewable resource. However, the induction machines commonly used as wind generators have stability problems similar to the transient stability of synchronous machines. To minimize power, frequency, and voltage fluctuations caused by network faults or random wind speed variations, control mechanisms are necessary. Wind Energy Systems: Solutions for Power Quality and Stabilization clearly explains how to solve stability and power quality issues of wind generator systems. Covering

  10. Balancing modern Power System with large scale of wind power

    OpenAIRE

    Basit, Abdul; Altin, Müfit; Hansen, Anca Daniela; Sørensen, Poul Ejnar

    2014-01-01

    Power system operators must ensure robust, secure and reliable power system operation even with a large scale integration of wind power. Electricity generated from the intermittent wind in large propor-tion may impact on the control of power system balance and thus deviations in the power system frequency in small or islanded power systems or tie line power flows in interconnected power systems. Therefore, the large scale integration of wind power into the power system strongly concerns the s...

  11. Impact of advanced wind power ancillary services on power system

    DEFF Research Database (Denmark)

    Hansen, Anca Daniela; Altin, Müfit

    The objective of this report is to illustrate and analyse, by means of simulation test cases, the impact of wind power advanced ancillary services, like inertial response (IR), power oscillation damping (POD) and synchronising power (SP) on the power system. Generic models for wind turbine, wind...... power plant and power system are used in the investigation....

  12. Intermittency and local heating in the solar wind.

    Science.gov (United States)

    Osman, K T; Matthaeus, W H; Wan, M; Rappazzo, A F

    2012-06-29

    Evidence for nonuniform heating in the solar wind plasma near current sheets dynamically generated by magnetohydrodynamic (MHD) turbulence is obtained using measurements from the ACE spacecraft. These coherent structures only constitute 19% of the data, but contribute 50% of the total plasma internal energy. Intermittent heating manifests as elevations in proton temperature near current sheets, resulting in regional heating and temperature enhancements extending over several hours. The number density of non-Gaussian structures is found to be proportional to the mean proton temperature and solar wind speed. These results suggest magnetofluid turbulence drives intermittent dissipation through a hierarchy of coherent structures, which collectively could be a significant source of coronal and solar wind heating.

  13. Investigation on wind energy-compressed air power system

    Institute of Scientific and Technical Information of China (English)

    贾光政; 王宣银; 吴根茂

    2004-01-01

    Wind energy is a pollution free and renewable resource widely distributed over China. Aimed at protecting the environment and enlarging application of wind energy, a new approach to application of wind energy by using compressed air power to some extent instead of electricity put forward. This includes: explaining the working principles and characteristics of the wind energy-compressed air power system; discussing the compatibility of wind energy and compressor capacity; presenting the theoretical model and computational simulation of the system. The obtained compressor capacity vs wind power relationship in certain wind velocity range can be helpful in the designing of the wind power-compressed air system. Results of investigations on the application of high-pressure compressed air for pressure reduction led to conclusion that pressure reduction with expander is better than the throttle regulator in energy saving.

  14. Systemic and localized scleroderma.

    Science.gov (United States)

    Chung, Lorinda; Lin, Jan; Furst, Daniel E; Fiorentino, David

    2006-01-01

    Sclerosing conditions of the skin are manifested by a full spectrum of presentations that includes skin-limited forms as well as those which can involve internal organs and result in death. At this point, we are just beginning to understand the mechanisms of tissue fibrosis, and it is likely that the fibrotic processes are a heterogeneous group of disorders in which perturbation of multiple molecular pathways, including vascular and immunologically mediated pathways, can lead to fibrosis. We now have some moderately effective therapies for vascular aspects of systemic sclerosis (eg, bosentan for pulmonary arterial hypertension, calcium-channel blockers for Raynaud's, or angiotensin-converting enzyme inhibitors for renal crisis). We also are beginning to find treatments interrupting the immunologic pathways that manifest as systemic sclerosis (eg, methotrexate for the skin or cyclophosphamide for the lungs). The basic process of fibrosis, however, awaits proven, effective therapy.

  15. Review of Energy Storage System for Wind Power Integration Support

    DEFF Research Database (Denmark)

    Zhao, Haoran; Wu, Qiuwei; Hu, Shuju

    2015-01-01

    -discharging characteristics, Energy Storage System (ESS) is considered as an effective tool to enhance the flexibility and controllability not only of a specific wind farm, but also of the entire grid. This paper reviews the state of the art of the ESS technologies for wind power integration support from different aspects....... Firstly, the modern ESS technologies and their potential applications for wind power integration support are introduced. Secondly, the planning problem in relation to the ESS application for wind power integration is reviewed, including the selection of the ESS type, and the optimal sizing and siting......With the rapid growth of wind energy development and increasing wind power penetration level, it will be a big challenge to operate the power system with high wind power penetration securely and reliably due to the inherent variability and uncertainty of wind power. With the flexible charging...

  16. Lunar Localization System (LLS) Project

    Data.gov (United States)

    National Aeronautics and Space Administration — In support of NASA's vision for space, the goal of this project is to research and prototype a multi-component localization system which uses radiometry and vision...

  17. Simulation of interaction between wind farm and power system

    DEFF Research Database (Denmark)

    Sørensen, Poul Ejnar; Hansen, Anca Daniela; Janosi, L.

    2002-01-01

    A dynamic model of the wind farm Hagesholm has been implemented in the dedicated power system simulation program DIgSILENT. The wind farm con- sists of six 2MW NM2000/72 wind turbines from NEG-Micon. The model has been verified using simultaneous powerquality measurements on the 10 kV terminals...

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

    Energy Technology Data Exchange (ETDEWEB)

    Wakui, Tetsuya; Hashizume, Takumi; Outa, Eisuke

    1999-07-01

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

  19. Technology assessment of wind energy conversion systems

    Energy Technology Data Exchange (ETDEWEB)

    Meier, B. W.; Merson, T. J.

    1980-09-01

    Environmental data for wind energy conversion systems (WECSs) have been generated in support of the Technology Assessment of Solar Energy (TASE) program. Two candidates have been chosen to characterize the WECS that might be deployed if this technology makes a significant contribution to the national energy requirements. One WECS is a large machine of 1.5-MW-rated capacity that can be used by utilities. The other WECS is a small machine that is characteristic of units that might be used to meet residential or small business energy requirements. Energy storage systems are discussed for each machine to address the intermittent nature of wind power. Many types of WECSs are being studied and a brief review of the technology is included to give background for choosing horizontal axis designs for this study. Cost estimates have been made for both large and small systems as required for input to the Strategic Environmental Assessment Simulation (SEAS) computer program. Material requirements, based on current generation WECSs, are discussed and a general discussion of environmental impacts associated with WECS deployment is presented.

  20. Assessing local population vulnerability to wind energy development with branching process models: an application to wind energy development

    Science.gov (United States)

    Erickson, Richard A.; Eager, Eric A.; Stanton, Jessica C.; Beston, Julie A.; Diffendorfer, James E.; Thogmartin, Wayne E.

    2015-01-01

    Quantifying the impact of anthropogenic development on local populations is important for conservation biology and wildlife management. However, these local populations are often subject to demographic stochasticity because of their small population size. Traditional modeling efforts such as population projection matrices do not consider this source of variation whereas individual-based models, which include demographic stochasticity, are computationally intense and lack analytical tractability. One compromise between approaches is branching process models because they accommodate demographic stochasticity and are easily calculated. These models are known within some sub-fields of probability and mathematical ecology but are not often applied in conservation biology and applied ecology. We applied branching process models to quantitatively compare and prioritize species locally vulnerable to the development of wind energy facilities. Specifically, we examined species vulnerability using branching process models for four representative species: A cave bat (a long-lived, low fecundity species), a tree bat (short-lived, moderate fecundity species), a grassland songbird (a short-lived, high fecundity species), and an eagle (a long-lived, slow maturation species). Wind turbine-induced mortality has been observed for all of these species types, raising conservation concerns. We simulated different mortality rates from wind farms while calculating local extinction probabilities. The longer-lived species types (e.g., cave bats and eagles) had much more pronounced transitions from low extinction risk to high extinction risk than short-lived species types (e.g., tree bats and grassland songbirds). High-offspring-producing species types had a much greater variability in baseline risk of extinction than the lower-offspring-producing species types. Long-lived species types may appear stable until a critical level of incidental mortality occurs. After this threshold, the risk of

  1. Wind Energy Innovative Systems conference proceedings

    Energy Technology Data Exchange (ETDEWEB)

    Vas, I. E. [ed.

    1979-12-01

    Separate abstracts are included for 20 of the 22 papers presented concerning innovative wind turbines which vary in design from the standard horizontal-axis propellor-type wind turbines. Two papers have been previously included in the data base.

  2. Research on the Wind Power Penetration Limit in Power System

    Directory of Open Access Journals (Sweden)

    Yang Zhang

    2013-08-01

    Full Text Available An approach to calculate the wind farm penetration capacity based on chance constrained programming combining with transient check was presented. A novel model for programming penetration of wind farm under indeterminacy operating mode was presented. Constraint condition consisted of conventional generator output limits, system spinning reserve, transmission lines capability, nodal voltage, system frequency etc, and genetic algorithm based on Monte Carlo simulating was used to solve the problem, and the actual sample system verified the feasibility of the model and method. Results for the application of this approach revealed the influencing factors of penetration of wind farm consisted of the parallel node voltage, the output variation range of wind generating set and mean wind speed etc. The research results have important practical significance, which can guide the actual wind farms in the planning and operation analysis of reality wind farm.  

  3. Short-Term Wind Speed Forecasting for Power System Operations

    KAUST Repository

    Zhu, Xinxin

    2012-04-01

    The emphasis on renewable energy and concerns about the environment have led to large-scale wind energy penetration worldwide. However, there are also significant challenges associated with the use of wind energy due to the intermittent and unstable nature of wind. High-quality short-term wind speed forecasting is critical to reliable and secure power system operations. This article begins with an overview of the current status of worldwide wind power developments and future trends. It then reviews some statistical short-term wind speed forecasting models, including traditional time series approaches and more advanced space-time statistical models. It also discusses the evaluation of forecast accuracy, in particular, the need for realistic loss functions. New challenges in wind speed forecasting regarding ramp events and offshore wind farms are also presented. © 2012 The Authors. International Statistical Review © 2012 International Statistical Institute.

  4. Design of gear systems for moving wind turbines

    Energy Technology Data Exchange (ETDEWEB)

    Venkatesh, C.; Bhuvanesh, N.; Kumar, V.S.; Aravindh, M. [Jansons Institute of Technology, Coimbatore, Tamilnadu (India)

    2012-07-01

    Power generation from renewable energy resources has been a widespread approach in today's technology fields. One of the cheapest energies from which power can be generated may be through wind energy resource. Very known method of power generation from wind energy is wind turbine. The constraints experienced in power generation from wind turbine is inconsistent power generation according to blow of wind. In this study, to overcome the constraints, a small wind turbine can be equipped on the top of the moving vehicle through which the velocity of the wind can be enhanced. This paper describes the design of gear system which is required for the moving wind mill. Also the paper focuses on modeling of the entire setup. (Author)

  5. A time-localized response of wave growth process under turbulent winds

    Directory of Open Access Journals (Sweden)

    Z. Ge

    2007-06-01

    Full Text Available Very short time series (with lengths of approximately 40 s or 5~7 wave periods of wind velocity fluctuations and wave elevation were recorded simultaneously and investigated using the wavelet bispectral analysis. Rapid changes in the wave and wind spectra were detected, which were found to be intimately related to significant energy transfers through transient quadratic wind-wave and wave-wave interactions. A possible pattern of energy exchange between the wind and wave fields was further deduced. In particular, the generation and variation of the strong wave-induced perturbation velocity in the wind can be explained by the strengthening and diminishing of the associated quadratic interactions, which cannot be unveiled by linear theories. On small time scales, the wave-wave quadratic interactions were as active and effective in transferring energy as the wind-wave interactions. The results also showed that the wind turbulence was occasionally effective in transferring energy between the wind and the wave fields, so that the background turbulence in the wind cannot be completely neglected. Although these effects are all possibly significant over short times, the time-localized growth of the wave spectrum may not considerably affect the long-term process of wave development.

  6. Applications of Systems Engineering to the Research, Design, and Development of Wind Energy Systems

    Energy Technology Data Exchange (ETDEWEB)

    Dykes, K.; Meadows, R.; Felker, F.; Graf, P.; Hand, M.; Lunacek, M.; Michalakes, J.; Moriarty, P.; Musial, W.; Veers, P.

    2011-12-01

    This paper surveys the landscape of systems engineering methods and current wind modeling capabilities to assess the potential for development of a systems engineering to wind energy research, design, and development. Wind energy has evolved from a small industry in a few countries to a large international industry involving major organizations in the manufacturing, development, and utility sectors. Along with this growth, significant technology innovation has led to larger turbines with lower associated costs of energy and ever more complex designs for all major subsystems - from the rotor, hub, and tower to the drivetrain, electronics, and controls. However, as large-scale deployment of the technology continues and its contribution to electricity generation becomes more prominent, so have the expectations of the technology in terms of performance and cost. For the industry to become a sustainable source of electricity, innovation in wind energy technology must continue to improve performance and lower the cost of energy while supporting seamless integration of wind generation into the electric grid without significant negative impacts on local communities and environments. At the same time, issues associated with wind energy research, design, and development are noticeably increasing in complexity. The industry would benefit from an integrated approach that simultaneously addresses turbine design, plant design and development, grid interaction and operation, and mitigation of adverse community and environmental impacts. These activities must be integrated in order to meet this diverse set of goals while recognizing trade-offs that exist between them. While potential exists today to integrate across different domains within the wind energy system design process, organizational barriers such as different institutional objectives and the importance of proprietary information have previously limited a system level approach to wind energy research, design, and

  7. 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....... The WT is, furthermore, equipped with a park level WPP voltage controller and comparisons are presented. The WT model for this work is a validated dynamic model of the 3.6 MW Siemens Wind Power WT. The study is based on modal analysis which is complemented with time domain simulations on the nonlinear...

  8. Primary reserve studies for high wind power penetrated systems

    DEFF Research Database (Denmark)

    Das, Kaushik; Altin, Müfit; Hansen, Anca Daniela;

    2015-01-01

    With high penetration of non-synchronous wind generations replacing conventional generators, the inertia of power system will reduce. A large disturbance in such a power system can cause faster frequency change in this power system and might invoke emergency defence strategies like underfrequency....... This paper further explores the capabilities of wind turbines to provide support during underfrequency to prevent load shedding. Maximum wind penetration possible without causing load shedding following a large disturbance is also investigated....

  9. ENERGY MANAGEMENT OF WIND/PV AND BATTERY HYBRID SYSTEM

    OpenAIRE

    M. F. Almi; M. Arrouf; H.Belmili; S. Boulouma; Bendib, B

    2014-01-01

    This paper deals with power control of a wind and solar hybrid generation system for interconnection operation with electric distribution system. Power control strategy is to extract the maximum energy available from varying condition of wind speed and solar irradiance while maintaining power quality at a satisfactory level. In order to capture the maximum power, variable speed control is employed for wind turbine and maximum power point tracking is applied for photovoltaic system. The grid i...

  10. Transient stability risk assessment of power systems incorporating wind farms

    DEFF Research Database (Denmark)

    Miao, Lu; Fang, Jiakun; Wen, Jinyu

    2013-01-01

    Large-scale wind farm integration has brought several aspects of challenges to the transient stability of power systems. This paper focuses on the research of the transient stability of power systems incorporating with wind farms by utilizing risk assessment methods. The detailed model of double ....... An investigation has been conducted into an improved 10-generator 39-bus system with a wind farm incorporated to verify the validity and feasibility of the risk assessment method proposed....

  11. Sea level changes induced by local winds on the west coast of India

    Digital Repository Service at National Institute of Oceanography (India)

    Mehra, P.; Tsimplis, M.N.; Desai, R.G.P.; Joseph, A.; Shaw, A.G.P.; Somayajulu, Y.K.; Cipollini, P.

    The contribution of atmospheric pressure and local wind to sea level variability at Goa (West coast of India) for the period 2007–2008 is investigated. Sea level data from a tide gauge are compared with measured local surface meteorological as well...

  12. Frequency control in power systems with high wind power penetration

    Energy Technology Data Exchange (ETDEWEB)

    Tarnowski, German Claudio [Technical Univ. of Denmark (Denmark). Centre for Electric Technology; Vestas Wind Systems A/S, Alsve (Denmark); Kjaer, Philip Carne [Vestas Wind Systems A/S, Alsve (Denmark); Oestergaard, Jacob [Technical Univ. of Denmark (Denmark). Centre for Electric Technology; Soerensen, Poul E. [Risoe National Laboratory for Sustainable Energy, Roskilde (Denmark). Wind Energy Dept.

    2010-07-01

    The fluctuating nature of wind power introduces several challenges to reliable operation of power system. With high wind power penetration, conventional power plants are displaced and wind speed fluctuations introduce large power imbalances which lead to power system frequency control and operational problems. This paper analysis the impact of wind power in the frequency control of power systems for different amount of controllable variable speed wind turbines. Real measurements from short term wind power penetration tests in a power system are shown and used to study the amount of total regulating power needed from conventional power plants. Dynamic simulations with validated model of the power system support the studies. The paper also presents control concepts for wind power plants necessary to achieve characteristic of frequency response and active power balancing similarly to conventional power plants, therefore allowing higher wind power penetration. As the power system dependency on wind power increases, wind power generation has to contribute with dynamic response and control actions similarly to conventional power plants. (orig.)

  13. Doppler Navigation System with a Non-Stabilized Antenna as a Sea-Surface Wind Sensor.

    Science.gov (United States)

    Nekrasov, Alexey; Khachaturian, Alena; Veremyev, Vladimir; Bogachev, Mikhail

    2017-06-09

    We propose a concept of the utilization of an aircraft Doppler Navigation System (DNS) as a sea-surface wind sensor complementary to its normal functionality. The DNS with an antenna, which is non-stabilized physically to the local horizontal with x-configured beams, is considered. We consider the wind measurements by the DNS configured in the multi-beam scatterometer mode for a rectilinear flight scenario. The system feasibility and the efficiency of the proposed wind algorithm retrieval are supported by computer simulations. Finally, the associated limitations of the proposed approach are considered.

  14. Photovoltaic-wind hybrid autonomous generation systems in Mongolia

    Energy Technology Data Exchange (ETDEWEB)

    Dei, Tsutomu; Ushiyama, Izumi

    2005-01-01

    Two hybrid stand-alone (autonomous) power systems, each with wind and PV generation, were studied as installed at health clinics in semi-desert and mountainous region in Mongolia. Meteorological and system operation parameters, including power output and the consumption of the system, were generally monitored by sophisticated monitoring. However, where wind and solar site information was lacking, justifiable estimates were made. The results show that there is a seasonal complementary relationship between wind and solar irradiation in Tarot Sum. The users understood the necessity of Demand Side Management of isolated wind-PV generation system through technology transfer seminars and actually executed DSM at both sites. (author)

  15. Optimal Control of a Wind Farm Group Using the WindEx System

    Directory of Open Access Journals (Sweden)

    Piotr Kacejko

    2014-09-01

    Full Text Available The aim of this paper is to present achievements obtained in implementing the framework project N R01 0021 06 in the Power System Department of Lublin University of Technology. The result of the work was “A system of optimal wind farm power control in the conditions of limited transmission capabilities of power networks”, which one of two main modules is a state estimator. The featured wind farm control system was integrated with a SCADA dispatcher system WindEx using the WebSVC service.

  16. Effect of Wind Farm Noise on Local Residents' Decision to Adopt Mitigation Measures.

    Science.gov (United States)

    Botelho, Anabela; Arezes, Pedro; Bernardo, Carlos; Dias, Hernâni; Pinto, Lígia M Costa

    2017-07-11

    Wind turbines' noise is frequently pointed out as the reason for local communities' objection to the installation of wind farms. The literature suggests that local residents feel annoyed by such noise and that, in many instances, this is significant enough to make them adopt noise-abatement interventions on their homes. Aiming at characterizing the relationship between wind turbine noise, annoyance, and mitigating actions, we propose a novel conceptual framework. The proposed framework posits that actual sound pressure levels of wind turbines determine individual homes' noise-abatement decisions; in addition, the framework analyzes the role that self-reported annoyance, and perception of noise levels, plays on the relationship between actual noise pressure levels and those decisions. The application of this framework to a particular case study shows that noise perception and annoyance constitutes a link between the two. Importantly, however, noise also directly affects people's decision to adopt mitigating measures, independently of the reported annoyance.

  17. Effect of Wind Farm Noise on Local Residents’ Decision to Adopt Mitigation Measures

    Science.gov (United States)

    Botelho, Anabela; Bernardo, Carlos; Dias, Hernâni; Pinto, Lígia M. Costa

    2017-01-01

    Wind turbines’ noise is frequently pointed out as the reason for local communities’ objection to the installation of wind farms. The literature suggests that local residents feel annoyed by such noise and that, in many instances, this is significant enough to make them adopt noise-abatement interventions on their homes. Aiming at characterizing the relationship between wind turbine noise, annoyance, and mitigating actions, we propose a novel conceptual framework. The proposed framework posits that actual sound pressure levels of wind turbines determine individual homes’ noise-abatement decisions; in addition, the framework analyzes the role that self-reported annoyance, and perception of noise levels, plays on the relationship between actual noise pressure levels and those decisions. The application of this framework to a particular case study shows that noise perception and annoyance constitutes a link between the two. Importantly, however, noise also directly affects people’s decision to adopt mitigating measures, independently of the reported annoyance. PMID:28696404

  18. Effect of Wind Farm Noise on Local Residents’ Decision to Adopt Mitigation Measures

    Directory of Open Access Journals (Sweden)

    Anabela Botelho

    2017-07-01

    Full Text Available Wind turbines’ noise is frequently pointed out as the reason for local communities’ objection to the installation of wind farms. The literature suggests that local residents feel annoyed by such noise and that, in many instances, this is significant enough to make them adopt noise-abatement interventions on their homes. Aiming at characterizing the relationship between wind turbine noise, annoyance, and mitigating actions, we propose a novel conceptual framework. The proposed framework posits that actual sound pressure levels of wind turbines determine individual homes’ noise-abatement decisions; in addition, the framework analyzes the role that self-reported annoyance, and perception of noise levels, plays on the relationship between actual noise pressure levels and those decisions. The application of this framework to a particular case study shows that noise perception and annoyance constitutes a link between the two. Importantly, however, noise also directly affects people’s decision to adopt mitigating measures, independently of the reported annoyance.

  19. Coordinated Frequency Control of Wind Turbines in Power Systems with High Wind Power Penetration

    DEFF Research Database (Denmark)

    Tarnowski, Germán Claudio

    particular views. These models were developed and verified during this work, basedaround a particular manufacturer’s wind turbine and on said isolated power system withwind power. The capability of variable speed wind turbines for providing Inertial Response is analysed. To perform this assessment, a control...... and the dynamic stability of the grid frequency under large disturbances would be compromised. The aim of this study is to investigate the integration of large scale wind power generation in power systems and its active power control.Novel methods and solutions dealing specifically with the electric frequency...... stability and high wind power penetration or in islanding situations are addressed. The review of relevant theoretical concepts is supported by measurements carried out on an isolated power system characterized by high wind power penetration. Different mathematical and simulation models are used in several...

  20. Integrating Systems Health Management with Adaptive Controls for a Utility-Scale Wind Turbine

    Science.gov (United States)

    Frost, Susan A.; Goebel, Kai; Trinh, Khanh V.; Balas, Mark J.; Frost, Alan M.

    2011-01-01

    Increasing 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. 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. Advanced adaptive controls can provide the mechanism to enable optimized operations that also provide the enabling technology for Systems Health Management goals. The work reported herein explores the integration of condition monitoring of wind turbine blades with contingency management and adaptive controls. Results are demonstrated using a high fidelity simulator of a utility-scale wind turbine.

  1. Land-use implications of wind-energy-conversion systems

    Science.gov (United States)

    Noun, R. J.

    1981-02-01

    An estimated 20 utilities in the United States are now investigating potential wind machine sites in their areas. Identifying sites for wind machine clusters (wind farms) involves more than just finding a location with a suitable wind resource. Consideration must also be given to the proximity of sites to existing transmission lines, environmental impacts, aesthetics, and legal concerns as well as the availability of and alternative uses for the land. These issues have made it increasingly difficult for utilities to bring conventional power plants on-line quickly. Utilities are now required, however, to give careful consideration to specific legal, social, and environmental questions raised by the siting of wind energy conversion systems.

  2. TAP Helps States and Local Governments Reach Their Wind Power Goals

    Energy Technology Data Exchange (ETDEWEB)

    2007-08-01

    Technical Assistance Project: Wind and Hydropower Program provides information to state and local officials regarding the U.S. Department of Energy's Technical Assistance Project (TAP). The TAP program provides access to wind energy experts at U.S. Department of Energy (DOE) national laboratories, including the National Renewable Energy Laboratory (NREL), Oak Ridge National Laboratory (ORNL), and Lawrence Berkeley National Laboratory (LBNL).

  3. Electrical Collection and Transmission Systems for Offshore Wind Power: Preprint

    Energy Technology Data Exchange (ETDEWEB)

    Green, J.; Bowen, A.; Fingersh, L.J.; Wan, Y.

    2007-03-01

    The electrical systems needed for offshore wind farms to collect power from wind turbines--and transmit it to shore--will be a significant cost element of these systems. This paper describes the development of a simplified model of the cost and performance of such systems.

  4. Rule - based Fault Diagnosis Expert System for Wind Turbine

    Directory of Open Access Journals (Sweden)

    Deng Xiao-Wen

    2017-01-01

    Full Text Available Under the trend of increasing installed capacity of wind power, the intelligent fault diagnosis of wind turbine is of great significance to the safe and efficient operation of wind farms. Based on the knowledge of fault diagnosis of wind turbines, this paper builds expert system diagnostic knowledge base by using confidence production rules and expert system self-learning method. In Visual Studio 2013 platform, C # language is selected and ADO.NET technology is used to access the database. Development of Fault Diagnosis Expert System for Wind Turbine. The purpose of this paper is to realize on-line diagnosis of wind turbine fault through human-computer interaction, and to improve the diagnostic capability of the system through the continuous improvement of the knowledge base.

  5. Simulations of an inhomogeneous stellar wind interacting with a pulsar wind in a binary system

    CERN Document Server

    Paredes-Fortuny, Xavier; Perucho, Manel; Ribó, Marc

    2014-01-01

    Binary systems containing a massive star and a non-accreting pulsar present strong interaction between the stellar and the pulsar winds. The properties of this interaction, which largely determine the non-thermal radiation in these systems, strongly depend on the structure of the stellar wind, which can be clumpy or strongly anisotropic, as in Be stars. We study numerically the influence of inhomogeneities in the stellar wind on the structure of the two-wind interaction region. We carried out for the first time axisymmetric, relativistic hydrodynamical simulations, with Lorentz factors of ~6 and accounting for the impact of instabilities, to study the impact in the two-wind interaction structure of an over-dense region of the stellar wind. We also followed the evolution of this over-dense region or clump as it faces the impact of the pulsar wind. For typical system parameters, and adopting a stellar wind inhomogeneity with a density contrast >~10, clumps with radii of a few percent of the binary size can sign...

  6. Colliding Winds in Low-Mass Binary Star Systems: wind interactions and implications for habitable planets

    CERN Document Server

    Johnstone, C P; Pilat-Lohinger, E; Bisikalo, D; Güdel, M; Eggl, S

    2015-01-01

    Context. In binary star systems, the winds from the two components impact each other, leading to strong shocks and regions of enhanced density and temperature. Potentially habitable circumbinary planets must continually be exposed to these interactions regions. Aims. We study, for the first time, the interactions between winds from low-mass stars in a binary system, to show the wind conditions seen by potentially habitable circumbinary planets. Methods. We use the advanced 3D numerical hydrodynamic code Nurgush to model the wind interactions of two identical winds from two solar mass stars with circular orbits and a binary separation of 0.5 AU. As input into this model, we use a 1D hydrodynamic simulation of the solar wind, run using the Versatile Advection Code. We derive the locations of stable and habitable orbits in this system to explore what wind conditions potentially habitable planets will be exposed to during their orbits. Results. Our wind interaction simulations result in the formation of two stron...

  7. Wind diesel systems - design assessment and future potential

    DEFF Research Database (Denmark)

    Infield, D.G.; Scotney, A.; Lundsager, P.

    1992-01-01

    system models for assessing both dynamic characteristics and overall performance and economics. An introduction is provided to the Wind Diesel Engineering Design Toolkit currently under development (for implementation on PC) by a consortium of leading wind diesel experts, representing six European......Diesels are the obvious form. of back-up electricity generation in small to medium sized wind systems. High wind penetrations pose significant technical problems for the system designer, ranging from component sizing to control specification and dynamic stability. A key role is seen for proven...

  8. Value analysis of wind energy systems to electric utilities

    Energy Technology Data Exchange (ETDEWEB)

    Percival, D.; Harper, J.

    1981-01-01

    A method has been developed for determining the value of utility-operated wind energy systems to electric utilities. The analysis is performed by a package of computer models that interface with most conventional utility planning models. Weather data are converted to wind turbine output powers, which are used to modify the utility load representation. Execution of the utility planning models with both the original and modified load representation yields the gross and marginal value ($/rated kW/) of the added wind energy systems. This value is then compared with cost estimates to determine if for economic reasons the wind energy system should be included in future generation plans.

  9. Optimizing Hybrid Wind/Diesel Generator System Using BAT Algorithm

    Directory of Open Access Journals (Sweden)

    Sudhir Sharma,

    2016-01-01

    Full Text Available Hybrid system comprising of Wind/Diesel generation system for a practical standalone application considers Wind turbine generators and diesel generator as primary power sources for generating electricity. Battery banks are considered as a backup power source. The total value of cost is reduced by meeting energy demand required by the customers. Bat optimization technique is implemented to optimize wind and battery modules. Wind and battery banks are considered as primary sources and diesel generator as a secondary power source for the system

  10. Systems and methods for an integrated electrical sub-system powered by wind energy

    Science.gov (United States)

    Liu, Yan; Garces, Luis Jose

    2008-06-24

    Various embodiments relate to systems and methods related to an integrated electrically-powered sub-system and wind power system including a wind power source, an electrically-powered sub-system coupled to and at least partially powered by the wind power source, the electrically-powered sub-system being coupled to the wind power source through power converters, and a supervisory controller coupled to the wind power source and the electrically-powered sub-system to monitor and manage the integrated electrically-powered sub-system and wind power system.

  11. Power fluctuations smoothing and regulations in wind turbine generator systems

    Science.gov (United States)

    Babazadehrokni, Hamed

    Wind is one of the most popular renewable energy sources and it has the potential to become the biggest energy source in future. Since the wind does not always blow constantly, the output wind power is not constant which may make some problem for the power grid. According to the grid code which is set by independent system operator, ISO, wind turbine generator systems need to follow some standards such as the predetermined acceptable power fluctuations. In order to smooth the output powers, the energy storage system and some power electronics modules are employed. The utilized power electronics modules in the wind turbine system can pursue many different goals, such as maintaining the voltage stability, frequency stability, providing the available and predetermined output active and reactive power. On the other side, the energy storage system can help achieving some of these goals but its main job is to store the extra energy when not needed and release the stored energy when needed. The energy storage system can be designed in different sizes, material and also combination of different energy storage systems (hybrid designs). Combination of power electronics devises and also energy storage system helps the wind turbine systems to smooth the output power according to the provided standards. In addition prediction of wind speed may improve the performance of wind turbine generator systems. In this research study all these three topics are studied and the obtained results are written in 10 papers which 7 of them are published and three of them are under process.

  12. Design Optimization and Evaluation of Different Wind Generator Systems

    DEFF Research Database (Denmark)

    Chen, Zhe; Li, Hui

    2008-01-01

    -stage gearbox (DFIG_3G) and with the single-stage gearbox (DFIG_1G), the electricity excited synchronous generator with the direct-driven (EESG_DD), and the VSCF squirrel cage induction generator with the three-stage gearbox (SCIG_3G). Firstly, the design models of wind turbines, three/single stage gearbox......With rapid development of wind power technologies and significant growth of wind power capacity installed worldwide, various wind generator systems have been developed and built. The objective of this paper is to evaluate various wind generator systems by optimization designs and comparisons....... In this paper, seven variable speed constant frequency (VSCF) wind generator systems are investigated, namely permanent magnet synchronous generators with the direct-driven (PMSG_DD), the single-stage gearbox (PMSG_1G) and three-stage gearbox (PMSG_3G) concepts, doubly fed induction generators with the three...

  13. Power System Operation with Large Scale Wind Power Integration

    DEFF Research Database (Denmark)

    Suwannarat, A.; Bak-Jensen, B.; Chen, Z.

    2007-01-01

    to the uncertain nature of wind power. In this paper, proposed models of generations and control system are presented which analyze the deviation of power exchange at the western Danish-German border, taking into account the fluctuating nature of wind power. The performance of the secondary control of the thermal...... power plants and the spinning reserves control from the Combined Heat and Power (CHP) units to achieve active power balance with the increased wind power penetration is presented.......The Danish power system starts to face problems of integrating thousands megawatts of wind power, which produce in a stochastic behavior due to natural wind fluctuations. With wind power capacities increasing, the Danish Transmission System Operator (TSO) is faced with new challenges related...

  14. Wind power planning in France (Aveyron), from State regulation to local planning

    Energy Technology Data Exchange (ETDEWEB)

    Nadai, Alain [CIRED - Centre Int. de Recherche sur l' Environnement et le Developpement (France); Labussiere, Olivier [Univ. de Pau et des Pays de l' Adour, Laboratoire Societe Environnement Territoire (France)

    2007-07-01

    Since a few years, French wind power has undertaken an unprecedented development. Few turbines are in place (756 MW), but the overall granted capacity amounts to about 2.7 GW. The administrative territory of Aveyron, one of the best wind power potential in the Country, is an interesting case for understanding the ways in which industrial wind power is being developed and regulated in France. The paper presents Aveyron wind power development by dividing it into three periods. For each period, we also sketch national developments in wind power policy.Between 1996 and 2000, Aveyron was one of the few places selected for developing wind parks under the French 'Eole 2005' call for tender. Between 2000 and 2005, French regulation shifted to fixed tariffs for small wind parks (less than 12 MW). The lack of planning approach provided developers with a window for profits. Numerous projects of small parks were submitted for development authorisation, overflowing the local administration. During the year of 2003, a new law on urbanism provided some rules for individual project developments without answering the key issue of territorial planning. In Aveyron, a local scheme devised by the decentralized branches of the State had a limited reach due to the lack of mandatory status and concentration.In July 2005, a new Energy Law imposed the design of Wind Power Development Zones (WPDZ) as a condition for tariff benefit (starting July 2007). WPDZ appeared to local actors as a promising tool but it came late. Many projects were already granted with construction permits.

  15. Renewable Energy Systems: Development and Perspectives of a Hybrid Solar-Wind System

    Directory of Open Access Journals (Sweden)

    C. Shashidhar

    2012-02-01

    Full Text Available Considering the intermittent natural energy resources and the seasonal un-balance, a phtovoltaic-wind hybrid electrical power supply system was developed to accommodate remote locations where a conventional grid connection is inconvenient or expensive. However, the hybrid system can also be applied with grid connection and owners are allowed to sell excessive power back to the electric utility. The proposed set-up consists of a photo-voltaic solar-cell array, a mast mounted wind generator, lead-acid storage batteries, an inverter unit to convert DC to AC, electrical lighting loads, electrical heating loads, several fuse and junction boxes and associated wiring, and test instruments for measuring voltages, currents, power factors, and harmonic contamination data throughout the system. The proposed hybrid solar-wind power generating system can be extensively used to illustrate electrical concepts in hands-on laboratories and also for demonstrations in the Industrial Technology curriculum. This paper describes an analysis of local PV-wind hybrid systems for supplying electricity to a private house, farmhouse or small company with electrical power depending on the site needs. The major system components, work principle and specific working condition are presented.

  16. A Wind Power and Load Prediction Based Frequency Control Approach for Wind-Diesel-Battery Hybrid Power System

    OpenAIRE

    Chao Peng; Zhenzhen Zhang; Jia Wu

    2015-01-01

    A frequency control approach based on wind power and load power prediction information is proposed for wind-diesel-battery hybrid power system (WDBHPS). To maintain the frequency stability by wind power and diesel generation as much as possible, a fuzzy control theory based wind and diesel power control module is designed according to wind power and load prediction information. To compensate frequency fluctuation in real time and enhance system disturbance rejection ability, a battery energy ...

  17. Combining Droop Curve Concepts with Control Systems for Wind Turbine Active Power Control: Preprint

    Energy Technology Data Exchange (ETDEWEB)

    Buckspan, A.; Aho, J.; Pao, L.; Fleming, P.; Jeong, Y.

    2012-06-01

    Wind energy is becoming a larger portion of the global energy portfolio and wind penetration has increased dramatically in certain regions of the world. This increasing wind penetration has driven the need for wind turbines to provide active power control (APC) services to the local utility grid, as wind turbines do not intrinsically provide frequency regulation services that are common with traditional generators. It is common for large scale wind turbines to be decoupled from the utility grid via power electronics, which allows the turbine to synthesize APC commands via control of the generator torque and blade pitch commands. Consequently, the APC services provided by a wind turbine can be more flexible than those provided by conventional generators. This paper focuses on the development and implementation of both static and dynamic droop curves to measure grid frequency and output delta power reference signals to a novel power set point tracking control system. The combined droop curve and power tracking controller is simulated and comparisons are made between simulations using various droop curve parameters and stochastic wind conditions. The tradeoffs involved with aggressive response to frequency events are analyzed. At the turbine level, simulations are performed to analyze induced structural loads. At the grid level, simulations test a wind plant's response to a dip in grid frequency.

  18. Economic incentives to wind systems commercialization. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Lotker, M.; Shaw, Jr, R. W.; Adolfson, W. F.; Bernardi, R. P.; Davidoff, P. H.; Eckhart, M. T.; Gunwaldsen, D. S.; Mettam, P. J.; Narayanan, P.; Sillin, J. O.

    1978-08-01

    This assessment of Economic Incentives to Wind Systems Commercialization is an analysis of the quantitative and qualitative impacts of a variety of Government funded economic incentives on Wind Energy Conversion Systems (WECS). The purpose of this study is to achieve better understanding of the relationship between implementation of specific economic incentives for WECS, and the factors surrounding WECS commercial introduction.

  19. Economic incentives to wind systems commercialization. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Lotker, M.; Shaw, Jr, R. W.; Adolfson, W. F.; Bernardi, R. P.; Davidoff, P. H.; Eckhart, M. T.; Gunwaldsen, D. S.; Mettam, P. J.; Narayanan, P.; Sillin, J. O.

    1978-08-01

    This assessment of Economic Incentives to Wind Systems Commercialization is an analysis of the quantitative and qualitative impacts of a variety of Government funded economic incentives on Wind Energy Conversion Systems (WECS). The purpose of this study is to achieve better understanding of the relationship between implementation of specific economic incentives for WECS, and the factors surrounding WECS commercial introduction.

  20. An Appropriate Wind Model for Wind Integrated Power Systems Reliability Evaluation Considering Wind Speed Correlations

    OpenAIRE

    Rajesh Karki; Dinesh Dhungana; Roy Billinton

    2013-01-01

    Adverse environmental impacts of carbon emissions are causing increasing concerns to the general public throughout the world. Electric energy generation from conventional energy sources is considered to be a major contributor to these harmful emissions. High emphasis is therefore being given to green alternatives of energy, such as wind and solar. Wind energy is being perceived as a promising alternative. This source of energy technology and its applications have undergone significant researc...

  1. Winding sense of galaxies around the Local Supercluster

    CERN Document Server

    Aryal, B

    2010-01-01

    We present an analysis of the winding sense (S and Z-shaped) of 1\\,621 field galaxies that have radial velocity between 3\\,000 km s$^{-1}$ to 5\\,000 km s$^{-1}$. The preferred alignments of S- and Z-shaped galaxies are studied using chi-square, auto-correlation and the Fourier tests. We classified total galaxies into 32 subsamples and noticed a good agreement between the position angle (PA) distribution of S- and Z-shaped galaxies. The homogeneous distribution of the S- and Z-shaped galaxies is noticed for the late-type spirals (Sc, Scd, Sd and Sm) than that of the early-types (Sa, Sab, Sb and Sbc). A significant dominance of S-mode galaxies is noticed in the barred spirals. A random alignment is noticed in the PA-distribution of Z- and S-mode spirals. In addition, homogeneous distribution of the S- and Z-shaped galaxies is found to be invariant under the global expansion. The PA-distribution of the total S-mode galaxies is found to be random, whereas preferred alignment is noticed for the total Z-mode galaxi...

  2. Magnetorotationally driven wind cycles in local disc models

    CERN Document Server

    Riols, A; Latter, H; Ross, J P

    2016-01-01

    Jets, from the protostellar to the AGN context, have been extensively studied but their connection to the turbulent dynamics of the underlying accretion disc is poorly understood. Following a similar approach to Lesur et al. (2013), we examine the role of the magnetorotational instability (MRI) in the production and acceleration of outflows from discs. Via a suite of one-dimensional shearing-box simulations of stratified discs we show that magneto-centrifugal winds exhibit cyclic activity with a period of 10-20 Omega^{-1}, a few times the orbital period. The cycle seems to be more vigorous for strong vertical field; it is robust to the variation of relevant parameters and independent of numerical details. The convergence of these solutions (in particular the mass loss rate) with vertical box size is also studied. By considering a sequence of magnetohydrostatic equilibria and their stability, the periodic activity may be understood as the succession of the following phases: (a) a dominant MRI channel mode, (b)...

  3. Winding sense of galaxies around the local supercluster

    Institute of Scientific and Technical Information of China (English)

    Binil Aryal

    2011-01-01

    We present an analysis of the winding sense (S and Z-shapes) of 1 621 field galaxies that have radial velocity between 3 000 km s- 1 and 5 000 km s-1. The preferred alignments of S- and Z-shaped galaxies are studied using chi-square, autocorrelation and Fourier series tests. We classify all the galaxies into 32 subsamples and notice a good agreement between the position angle (PA) distribution of the S- and Z-shaped galaxies. The homogeneous distribution of the S- and Z-shaped galaxies is more noticeable for the late-type spirals (Sc, Scd, Sd and Sm) than for the early-types (Sa, Sab, Sb and Sbc). A significant dominance of S-mode galaxies is apparent in the barred spirals. A random alignment is evident in the PA-distribution of Z- and S-mode spirals. In addition, a homogeneous distribution of the S- and Z-shaped galaxies is found to be invariant under global expansion. The PA-distribution of the total S-mode galaxies is found to be random, whereas a preferred alignment is clear for all the Z-mode galaxies. It is found that the galactic planes of Z-mode galaxies tend to lie in the equatorial plane.

  4. 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

    turbine model which is developed for the short-term voltage stability studies can be inaccurate and sufficient for the frequency stability studies. Accordingly, a complete and detailed wind power plant model for every kind of study is not feasible in terms of the computational time and also...... 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....

  5. Generic 12-Bus Test System for Wind Power Integration Studies

    DEFF Research Database (Denmark)

    Adamczyk, Andrzej Grzegorz; Altin, Müfit; Göksu, Ömer;

    2012-01-01

    High wind power penetration levels into power systems requires an appropriate power system model when assessing impact on the overall system stability. The model should capture the wide range of dynamics related to the wind integration studies, such as voltage control, synchronizing power control...... system characteristics. Additionally, the power system model should be simple and computationally manageable in order to simulate multiple scenarios with different control parameters in a reasonable time. In this paper, a generic power system model is presented in order to comprehend the wind integration...

  6. 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,...

  7. 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. ...

  8. 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,...

  9. Cropping system effects on wind erosion potential

    Science.gov (United States)

    Wind erosion of soil is a destructive process impacting crop productivity and human health and safety. The mechanics of wind erosion and soil properties that influence erosion are well understood. Less well-studied are the effects that cropping intensity has upon those soil properties. We collected ...

  10. Wind data analysis for the design of a hybrid generation system at the Algodoal Island - Brazil

    Energy Technology Data Exchange (ETDEWEB)

    Bezerra, U.H.; Pinho, J.T.; J.C. da Cunha, D. de; Araujo, A.C.S. [Universidade Federal do Para (Brazil)

    1997-12-31

    The northeastern coast of the State of Para and the Marajo Island - in Brazil, exhibit a wind potential that seems adequate to the generation of electric energy to supply local demands. These local demands are mostly formed by small towns and villages located invariably far from the big urban centers with little or no possibility to be supplied by the utility grid. In this paper it is intended to report the studies being conducted to design a hybrid wind diesel system to attend a small population center, namely the Algodoal Island, that is a representative sample of this region. It will be described the process of data acquisition and statistical treatment as well as some environmental, social and economic aspects regarding the Algodoal Island. Finally it will be presented a preliminary estimate of energy demand for this locality as well as a probable wind-diesel system arrangement to supply this demand.

  11. Balancing modern Power System with large scale of wind power

    DEFF Research Database (Denmark)

    Basit, Abdul; Altin, Müfit; Hansen, Anca Daniela

    2014-01-01

    Power system operators must ensure robust, secure and reliable power system operation even with a large scale integration of wind power. Electricity generated from the intermittent wind in large propor-tion may impact on the control of power system balance and thus deviations in the power system...... to be analysed with improved analytical tools and techniques. This paper proposes techniques for the active power balance control in future power systems with the large scale wind power integration, where power balancing model provides the hour-ahead dispatch plan with reduced planning horizon and the real time...... frequency in small or islanded power systems or tie line power flows in interconnected power systems. Therefore, the large scale integration of wind power into the power system strongly concerns the secure and stable grid operation. To ensure the stable power system operation, the evolving power system has...

  12. Triboelectric nanogenerator for harvesting wind energy and as self-powered wind vector sensor system.

    Science.gov (United States)

    Yang, Ya; Zhu, Guang; Zhang, Hulin; Chen, Jun; Zhong, Xiandai; Lin, Zong-Hong; Su, Yuanjie; Bai, Peng; Wen, Xiaonan; Wang, Zhong Lin

    2013-10-22

    We report a triboelectric nanogenerator (TENG) that plays dual roles as a sustainable power source by harvesting wind energy and as a self-powered wind vector sensor system for wind speed and direction detection. By utilizing the wind-induced resonance vibration of a fluorinated ethylene-propylene film between two aluminum foils, the integrated TENGs with dimensions of 2.5 cm × 2.5 cm × 22 cm deliver an output voltage up to 100 V, an output current of 1.6 μA, and a corresponding output power of 0.16 mW under an external load of 100 MΩ, which can be used to directly light up tens of commercial light-emitting diodes. Furthermore, a self-powered wind vector sensor system has been developed based on the rationally designed TENGs, which is capable of detecting the wind direction and speed with a sensitivity of 0.09 μA/(m/s). This work greatly expands the applicability of TENGs as power sources for self-sustained electronics and also self-powered sensor systems for ambient wind detection.

  13. IEA Task 32: Wind Lidar Systems for Wind Energy Deployment (LIDAR)

    Energy Technology Data Exchange (ETDEWEB)

    Kuhn, Martin; Trabucchi, Davide; Clifton, Andrew; Courtney, Mike; Rettenmeier, Andreas

    2016-05-09

    Under the International Energy Agency Wind Implementing Agreement (IEA Wind) Task 11, researchers started examining novel applications for remote sensing and the issues around them during the 51st topical expert meeting about remote sensing in January 2007. The 59th topical expert meeting organized by Task 11 in October 2009 was also dedicated to remote sensing, and the first draft of the Task's recommended practices on remote sensing was published in January 2013. The results of the Task 11 topical expert meetings provided solid groundwork for a new IEA Wind Task 32 on wind lidar technologies. Members of the wind community identified the need to consolidate the knowledge about wind lidar systems to facilitate their use, and to investigate how to exploit the advantages offered by this technology. This was the motivation that led to the start of IEA Wind Task 32 'Lidar Application for Wind Energy Deployment' in November 2011. The kick-off was meeting was held in May 2012.

  14. Offshore Wind Balance-of-System Cost Modeling

    Energy Technology Data Exchange (ETDEWEB)

    Maness, Michael; Stehly, Tyler; Maples, Ben; Mone, Christopher

    2015-09-29

    Offshore wind balance-of-system (BOS) costs contribute up to 70% of installed capital costs. Thus, it is imperative to understand the impact of these costs on project economics as well as potential cost trends for new offshore wind technology developments. As a result, the National Renewable Energy Laboratory (NREL) developed and recently updated a BOS techno-economic model using project cost estimates created from wind energy industry sources.

  15. Wind power electric systems modeling, simulation and control

    CERN Document Server

    Rekioua, Djamila

    2014-01-01

    The book helps readers understand key concepts in standalone and grid connected wind energy systems and features analysis into the modeling and optimization of commonly used configurations through the implementation of different control strategies.Utilizing several electrical machinery control approaches, such as vector control and direct torque control 'Wind Power Electric Systems' equips readers with the means to understand, assess and develop their own wind energy systems and to evaluate the performance of such systems.Mathematical models are provided for each system and a corresponding MAT

  16. A hybrid reconfigurable solar and wind energy system

    Science.gov (United States)

    Gadkari, Sagar A.

    We study the feasibility of a novel hybrid solar-wind hybrid system that shares most of its infrastructure and components. During periods of clear sunny days the system will generate electricity from the sun using a parabolic concentrator. The concentrator is formed by individual mirror elements and focuses the light onto high intensity vertical multi-junction (VMJ) cells. During periods of high wind speeds and at night, the same concentrator setup will be reconfigured to channel the wind into a wind turbine which will be used to harness wind energy. In this study we report on the feasibility of this type of solar/wind hybrid energy system. The key mechanisms; optics, cooling mechanism of VMJ cells and air flow through the system were investigated using simulation tools. The results from these simulations, along with a simple economic analysis giving the levelized cost of energy for such a system are presented. An iterative method of design refinement based on the simulation results was used to work towards a prototype design. The levelized cost of the system achieved in the economic analysis shows the system to be a good alternative for a grid isolated site and could be used as a standalone system in regions of lower demand. The new approach to solar wind hybrid system reported herein will pave way for newer generation of hybrid systems that share common infrastructure in addition to the storage and distribution of energy.

  17. Simulation and optimum design of hybrid solar-wind and solar-wind-diesel power generation systems

    Science.gov (United States)

    Zhou, Wei

    Solar and wind energy systems are considered as promising power generating sources due to its availability and topological advantages in local power generations. However, a drawback, common to solar and wind options, is their unpredictable nature and dependence on weather changes, both of these energy systems would have to be oversized to make them completely reliable. Fortunately, the problems caused by variable nature of these resources can be partially overcome by integrating these two resources in a proper combination to form a hybrid system. However, with the increased complexity in comparison with single energy systems, optimum design of hybrid system becomes more complicated. In order to efficiently and economically utilize the renewable energy resources, one optimal sizing method is necessary. This thesis developed an optimal sizing method to find the global optimum configuration of stand-alone hybrid (both solar-wind and solar-wind-diesel) power generation systems. By using Genetic Algorithm (GA), the optimal sizing method was developed to calculate the system optimum configuration which offers to guarantee the lowest investment with full use of the PV array, wind turbine and battery bank. For the hybrid solar-wind system, the optimal sizing method is developed based on the Loss of Power Supply Probability (LPSP) and the Annualized Cost of System (ACS) concepts. The optimization procedure aims to find the configuration that yields the best compromise between the two considered objectives: LPSP and ACS. The decision variables, which need to be optimized in the optimization process, are the PV module capacity, wind turbine capacity, battery capacity, PV module slope angle and wind turbine installation height. For the hybrid solar-wind-diesel system, minimization of the system cost is achieved not only by selecting an appropriate system configuration, but also by finding a suitable control strategy (starting and stopping point) of the diesel generator. The

  18. A short-term ensemble wind speed forecasting system for wind power applications

    Science.gov (United States)

    Baidya Roy, S.; Traiteur, J. J.; Callicutt, D.; Smith, M.

    2011-12-01

    This study develops an adaptive, blended forecasting system to provide accurate wind speed forecasts 1 hour ahead of time for wind power applications. The system consists of an ensemble of 21 forecasts with different configurations of the Weather Research and Forecasting Single Column Model (WRFSCM) and a persistence model. The ensemble is calibrated against observations for a 2 month period (June-July, 2008) at a potential wind farm site in Illinois using the Bayesian Model Averaging (BMA) technique. The forecasting system is evaluated against observations for August 2008 at the same site. The calibrated ensemble forecasts significantly outperform the forecasts from the uncalibrated ensemble while significantly reducing forecast uncertainty under all environmental stability conditions. The system also generates significantly better forecasts than persistence, autoregressive (AR) and autoregressive moving average (ARMA) models during the morning transition and the diurnal convective regimes. This forecasting system is computationally more efficient than traditional numerical weather prediction models and can generate a calibrated forecast, including model runs and calibration, in approximately 1 minute. Currently, hour-ahead wind speed forecasts are almost exclusively produced using statistical models. However, numerical models have several distinct advantages over statistical models including the potential to provide turbulence forecasts. Hence, there is an urgent need to explore the role of numerical models in short-term wind speed forecasting. This work is a step in that direction and is likely to trigger a debate within the wind speed forecasting community.

  19. 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...

  20. 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...... strategies have different goals e.g. fast response over disturbances, optimum power efficiency over a wider range of wind speeds, voltage ride-through capability including grid support. A dynamic model of a DC connection for active stall wind farms to the grid including the control is also implemented...

  1. Power Electronics for the Next Generation Wind Turbine System

    DEFF Research Database (Denmark)

    Ma, Ke

    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......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...... semiconductors is emphasized and a multidisciplinary approach for the stress analysis is introduced. Based on the proposed criteria and tools, the electrical and thermal behaviors of wind power converters are investigated under both normal and fault conditions, where the factors of wind speeds, grid codes...

  2. Damage localization in a residential-sized wind turbine blade by use of the SDDLV method

    DEFF Research Database (Denmark)

    Johansen, Rasmus Johan; Hansen, Lasse Majgaard; Ulriksen, Martin Dalgaard

    2015-01-01

    of the SDDLV method for localization of structural damages in a cantilevered residential-sized wind turbine blade. The blade was excited by an unmeasured multi-impulse load and the resulting dynamic response was captured through accelerometers mounted along the blade. The static pseudo-loads were applied...

  3. Offshore wind farms in the local environment - an examination at Horns Rev Offshore Wind Farm. Background report; Havvindmoeller i lokalomraadet - en undersoegelse ved Horns Rev Havmoellepark. Baggrundsrapport

    Energy Technology Data Exchange (ETDEWEB)

    Kuehn, Susanne

    2005-07-01

    Horns Rev Offshore Wind Farm was built in 2002. A presentation is made of a sociological, qualitative survey on the local community's reception of the offshore wind farm. The survey aims at identifying attitudes towards the farm before and after the construction, with a view to identifying possible changes in attitudes, and explain the reasons for these (ml)

  4. Development of large wind energy power generation system

    Science.gov (United States)

    1985-01-01

    The background and development of an experimental 100 kW wind-energy generation system are described, and the results of current field tests are presented. The experimental wind turbine is a two-bladed down-wind horizontal axis propeller type with a 29.4 m diameter rotor and a tower 28 m in height. The plant was completed in March, 1983, and has been undergoing trouble-free tests since then. The present program calls for field tests during two years from fiscal 1983 to 1984. The development of technologies relating to the linkage and operation of wind-energy power generation system networks is planned along with the acquisition of basic data for the development of a large-scale wind energy power generation system.

  5. Modeling and Parameter Estimation of a Small Wind Generation System

    Directory of Open Access Journals (Sweden)

    Carlos A. Ramírez Gómez

    2013-11-01

    Full Text Available The modeling and parameter estimation of a small wind generation system is presented in this paper. The system consists of a wind turbine, a permanent magnet synchronous generator, a three phase rectifier, and a direct current load. In order to estimate the parameters wind speed data are registered in a weather station located in the Fraternidad Campus at ITM. Wind speed data were applied to a reference model programed with PSIM software. From that simulation, variables were registered to estimate the parameters. The wind generation system model together with the estimated parameters is an excellent representation of the detailed model, but the estimated model offers a higher flexibility than the programed model in PSIM software.

  6. A review of the European offshore wind innovation system

    NARCIS (Netherlands)

    Wieczorek, A.J.; Negro, S.O.; Harmsen, R.; Heimeriks, G.J.; Luo, L.; Hekkert, M.P.

    2013-01-01

    Offshore wind has the potential of becoming an important pillar of the future European energy system. It can contribute to policy objectives on climate change, energy security, green growth and social progress. However, the large potential of offshore wind does not automatically lead to a large shar

  7. Power Electronics for the Next Generation Wind Turbine System

    DEFF Research Database (Denmark)

    Ma, Ke

    This book presents recent studies on the power electronics used for the next generation wind turbine system. Some criteria and tools for evaluating and improving the critical performances of the wind power converters have been proposed and established. The book addresses some emerging problems...

  8. Wind Energy Conversion Systems. A Unit of Instruction.

    Science.gov (United States)

    Greenwald, Martin

    The number of secondary schools, colleges, and universities offering courses in wind energy machine construction, repair, and installation, continues to increase. It is the purpose of this unit to include the study of wind energy conversion systems (WECS) as an integral part of related vocational and technical curriculum materials. The unit's…

  9. Power Electronics for the Next Generation Wind Turbine System

    DEFF Research Database (Denmark)

    Ma, Ke

    This book presents recent studies on the power electronics used for the next generation wind turbine system. Some criteria and tools for evaluating and improving the critical performances of the wind power converters have been proposed and established. The book addresses some emerging problems...

  10. X-ray emission from the local hot bubble and solar wind charge exchange

    Science.gov (United States)

    Uprety, Youaraj

    DXL (Diffuse X-rays from the Local galaxy) is a sounding rocket mission to quantify the Solar Wind Charge Exchange (SWCX) X-ray emission in the interplanetary medium, and separate its contribution from the Local Hot Bubble (LHB) emission. The first launch of DXL took place in December 2012. This thesis will describe the DXL instrumentation and calibrations, and discuss the results obtained. The mission uses two large area proportional counters to scan through the Helium Focusing Cone (HFC), a high helium density region in the solar system emitting excess X-rays due to SWCX. Using well determined models of the interplanetary neutral distribution and comparing the DXL results with data from the same region obtained by the ROSAT satellite away from the cone, we calculated that SWCX contributes at most 36% to the ¼ keV ROSAT band and 13% to the ¾ keV ROSAT band, in the galactic plane. This provides a firm proof for existence of a LHB which dominates the Diffuse X-ray Background (DXB) at ¼ keV, while raising new questions on the origin of the ¾ keV emission.

  11. Damage localization in a residential-sized wind turbine blade by use of the SDDLV method

    Science.gov (United States)

    Johansen, R. J.; Hansen, L. M.; Ulriksen, M. D.; Tcherniak, D.; Damkilde, L.

    2015-07-01

    The stochastic dynamic damage location vector (SDDLV) method has previously proved to facilitate effective damage localization in truss- and plate-like structures. The method is based on interrogating damage-induced changes in transfer function matrices in cases where these matrices cannot be derived explicitly due to unknown input. Instead, vectors from the kernel of the transfer function matrix change are utilized; vectors which are derived on the basis of the system and state-to-output mapping matrices from output-only state-space realizations. The idea is then to convert the kernel vectors associated with the lowest singular values into static pseudo-loads and apply these alternately to an undamaged reference model with known stiffness matrix. By doing so, the stresses in the potentially damaged elements will, theoretically, approach zero. The present paper demonstrates an application of the SDDLV method for localization of structural damages in a cantilevered residential-sized wind turbine blade. The blade was excited by an unmeasured multi-impulse load and the resulting dynamic response was captured through accelerometers mounted along the blade. The static pseudo-loads were applied to a finite element (FE) blade model, which was tuned against the modal parameters of the actual blade. In the experiments, an undamaged blade configuration was analysed along with different damage scenarios, hereby testing the applicability of the SDDLV method.

  12. Robust multi-model control of an autonomous wind power system

    Energy Technology Data Exchange (ETDEWEB)

    Cutululis, Nicolas Antonio; Hansen, Anca Daniela; Soerensen, Poul [Risoe National Lab., Wind Energy Dept., Roskilde (Denmark); Ceanga, Emil [' Dunarea de Jos' Univ., Faculty of Electrical Engineering, Galati (Romania)

    2006-07-01

    This article presents a robust multi-model control structure for a wind power system that uses a variable speed wind turbine (VSWT) driving a permanent magnet synchronous generator (PMSG) connected to a local grid. The control problem consists in maximizing the energy captured from the wind for varying wind speeds. The VSWT-PMSG linearized model analysis reveals the resonant nature of its dynamic at points on the optimal regimes characteristic (ORC). The natural frequency of the system and the damping factor are strongly dependent on the operating point on the ORC. Under these circumstances a robust multi-model control structure is designed. The simulation results prove the viability of the proposed control structure. (Author)

  13. Robust multi-model control of an autonomous wind power system

    Science.gov (United States)

    Cutululis, Nicolas Antonio; Ceanga, Emil; Hansen, Anca Daniela; Sørensen, Poul

    2006-09-01

    This article presents a robust multi-model control structure for a wind power system that uses a variable speed wind turbine (VSWT) driving a permanent magnet synchronous generator (PMSG) connected to a local grid. The control problem consists in maximizing the energy captured from the wind for varying wind speeds. The VSWT-PMSG linearized model analysis reveals the resonant nature of its dynamic at points on the optimal regimes characteristic (ORC). The natural frequency of the system and the damping factor are strongly dependent on the operating point on the ORC. Under these circumstances a robust multi-model control structure is designed. The simulation results prove the viability of the proposed control structure. Copyright

  14. Short-term wind-speed forecasting system for wind power applications

    Science.gov (United States)

    Traiteur, J. J.; Baidya Roy, S.

    2010-12-01

    Accurate short-term wind speed forecasts for utility-scale large wind farms will be crucial for the U.S. Department of Energy's goal of providing 20% of total electricity from wind by 2030. Communicating the level of uncertainty in these wind speed forecasts will allow the industry to better quantify the level of financial risk inherent with these forecasts. In this study, a computationally efficient and accurate system for short-term (0-60 mins) forecasting of wind speed is developed. This system uses a 27 member ensemble of the Weather Research and Forecasting Single-Column Model (WRF-SCM) to generate a probability density function (pdf) of daytime forecasts at 90m height for a location in Chalmers Township in West/Central Illinois. The WRF-SCM ensemble is initialized by the 20km Rapid Update Cycle (RUC) 00h forecast and perturbed by both perturbations in the initial conditions and physics options. The pdf is calibrated using Bayesian Model Averaging (BMA) where the individual forecasts are weighted according to their performance. This combination of a numerical weather prediction ensemble system and Bayesian statistics allows for accurate and computationally efficient prediction of 1 hour wind speed and the level of uncertainty in the forecasts.

  15. Communications for Coordinative Control of Wind Power Systems

    DEFF Research Database (Denmark)

    Wei, Mu

    system control strategies for wind power integration, in order to achieve coordinative control for a secure and efficient power system. The project basically contains three main aspects: studies on DGS (Distributed Generation System) characteristics, analysis of communication technologies......, and integration of power system and communication system. For the DGS studies, the main components, such as WTs (Wind Turbines) and CHPs (Combined Head and Power), are modelled. Since WTs are sensitive to disturbances, one focus of this PhD study is the investigation of WTs characteristics; mainly covering FSIG...... (Fixed Speed Induction Generator) and DFIG (Doubly-Fed Induction Generator) based wind turbine systems. Based on the study, the critical points to stabilize FSWTs (Fixed Speed Wind Turbines), after disturbances, are determined. This demands the latency requirements on the possible control and protection...

  16. Review of Power System Stability with High Wind Power Penetration

    DEFF Research Database (Denmark)

    Hu, Rui; Hu, Weihao; Chen, Zhe

    2015-01-01

    analyzing methods and stability improvement approaches. With increasing wind power penetration, system balancing and the reduced inertia may cause a big threaten for stable operation of power systems. To mitigate or eliminate the wind impacts for high wind penetration systems, although the practical......This paper presents an overview of researches on power system stability with high wind power penetration including analyzing methods and improvement approaches. Power system stability issues can be classified diversely according to different considerations. Each classified issue has special...... and reliable choices currently are the strong outside connections or sufficient reserve capacity constructions, many novel theories and approaches are invented to investigate the stability issues, looking forward to an extra-high penetration or totally renewable resource based power systems. These analyzing...

  17. Performance Analysis of a Grid connected Wind Energy system

    Directory of Open Access Journals (Sweden)

    Manju Khare

    2016-07-01

    Full Text Available This paper is concerned with the study of a small wind generation system used for battery charging. A topology that aims at the exploitation of maximum energy from the generator, generated at low speed is proposed. The characteristics of the wind turbine and the generator are discussed, providing the overview of the system modeling. Simulation tests of the system are obtained using MATLAB/SIMULINK. We adopt compact permanent magnet type synchronous generator, which doesn’t need exciting current, and step- up /down buck-boost chopper to wind power generating system of a few kW output with rotor speed sensor. In addition, we employ rectifier circuit using Diode Bridge instead of AC-DC converter with PWM method and a battery charging system. Using these methods we achieve a simple wind power generation system

  18. Efficiency improvement for wind energy pumped storage systems

    DEFF Research Database (Denmark)

    Forcos, A.; Marinescu, C.; Teodorescu, Remus

    2011-01-01

    Integrating wind energy into the grid may raise stability problems. Solutions for avoiding these situations are studied and energy storage methods are suitable for balancing the energy between the wind turbine and grid. In this paper, an autonomous wind turbine pumped storage system is presented....... The focus of this paper is to improve the efficiency of this system, which is small at low power levels. The driving motorpump group of the storage system is the key point presented in this paper for efficiency improving. Two control methods, experimentally implemented for induction machine are presented...

  19. Magnetised winds in single and binary star systems

    Science.gov (United States)

    Johnstone, Colin

    2016-07-01

    Stellar winds are fundamentally important for the stellar magnetic activity evolution and for the immediate environment surrounding their host stars. Ionised winds travel at hundreds of km/s, impacting planets and clearing out large regions around the stars called astropheres. Winds influence planets in many ways: for example, by compressing the magnetosphere and picking up atmospheric particles, they can cause significant erosion of a planetary atmosphere. By removing angular momentum, winds cause the rotation rates of stars to decrease as they age. This causes the star's magnetic dynamo to decay, leading to a significant decay in the star's levels of X-ray and extreme ultraviolet emission. Despite their importance, little is currently known about the winds of other Sun-like stars. Their small mass fluxes have meant that no direct detections have so far been possible. What is currently known has either been learned indirectly or through analogies with the solar wind. In this talk, I will review what is known about the properties and evolution of the winds of other Sun-like stars. I will also review wind dynamics in binary star systems, where the winds from both stars impact each other, leading to shocks and compression regions.

  20. Upper wind observing systems used for meteorological operations

    Directory of Open Access Journals (Sweden)

    J. Nash

    Full Text Available Methods of upper wind measurements used in operational meteorology have been reviewed to provide guidance to those developing wind profiler radar systems. The main limitations of the various methods of tracking weather balloons are identified using results from the WMO radiosonde comparisons and additional tests in the United Kingdom. Costs associated with operational balloon measurements are reviewed. The sampling and quality of operational aircraft wind observations are illustrated with examples from the ASDAR system. Measurement errors in horizontal winds are quantified wherever possible. When tracking equipment is functioning correctly, random errors in southerly and westerly wind component measurements from aircraft and weather balloons are usually in the range 0.5-2 m s-1.

  1. 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...... better control performance under the unbalanced AC source. It is concluded that power electronics will play more important role and regulate all the generated power in the next generation wind turbine system. In this case, the stress in the converter components becomes more critical because the power...

  2. FEM Simulation of Small Wind Power Generating System Using PMSG

    Science.gov (United States)

    Kesamaru, Katsumi; Ohno, Yoshihiro; Sonoda, Daisuke

    The paper describes a new approach to simulate the small wind power generating systems using PMSG, in which the output is connected to constant resistive load, such as heaters, through the rectifier and the dc chopper. The dynamics of the wind power generating system is presented, and it is shown by simulation results that this approach is useful for system dynamics, such as starting phenomena.

  3. A simulation approach to sizing hybrid photovoltaic and wind systems

    Science.gov (United States)

    Anderson, L. A.

    1983-12-01

    A simulation approach to sizing hybrid photovoltaic and wind systems provides a combination of components to realize zero downtime and minimum initial or life-cycle cost. Using Dayton, OH as a test site for weather data, cost advantages in the neighborhood of four are predicted for a hybrid system with battery storage when compared to a wind-energy-only system for the same electrical load.

  4. Sizing and Simulation of PV-Wind Hybrid Power System

    OpenAIRE

    Mustafa Engin

    2013-01-01

    A sizing procedure is developed for hybrid system with the aid of mathematical models for photovoltaic cell, wind turbine, and battery that are readily present in the literature. This sizing procedure can simulate the annual performance of different kinds of photovoltaic-wind hybrid power system structures for an identified set of renewable resources, which fulfills technical limitations with the lowest energy cost. The output of the program will display the performance of the system during t...

  5. Coupled Dynamic Modeling of Floating Wind Turbine Systems: Preprint

    Energy Technology Data Exchange (ETDEWEB)

    Wayman, E. N.; Sclavounos, P. D.; Butterfield, S.; Jonkman, J.; Musial, W.

    2006-03-01

    This article presents a collaborative research program that the Massachusetts Institute of Technology (MIT) and the National Renewable Energy Laboratory (NREL) have undertaken to develop innovative and cost-effective floating and mooring systems for offshore wind turbines in water depths of 10-200 m. Methods for the coupled structural, hydrodynamic, and aerodynamic analysis of floating wind turbine systems are presented in the frequency domain. This analysis was conducted by coupling the aerodynamics and structural dynamics code FAST [4] developed at NREL with the wave load and response simulation code WAMIT (Wave Analysis at MIT) [15] developed at MIT. Analysis tools were developed to consider coupled interactions between the wind turbine and the floating system. These include the gyroscopic loads of the wind turbine rotor on the tower and floater, the aerodynamic damping introduced by the wind turbine rotor, the hydrodynamic damping introduced by wave-body interactions, and the hydrodynamic forces caused by wave excitation. Analyses were conducted for two floater concepts coupled with the NREL 5-MW Offshore Baseline wind turbine in water depths of 10-200 m: the MIT/NREL Shallow Drafted Barge (SDB) and the MIT/NREL Tension Leg Platform (TLP). These concepts were chosen to represent two different methods of achieving stability to identify differences in performance and cost of the different stability methods. The static and dynamic analyses of these structures evaluate the systems' responses to wave excitation at a range of frequencies, the systems' natural frequencies, and the standard deviations of the systems' motions in each degree of freedom in various wind and wave environments. This article in various wind and wave environments. This article explores the effects of coupling the wind turbine with the floating platform, the effects of water depth, and the effects of wind speed on the systems' performance. An economic feasibility analysis of

  6. Tensions between Scottish National Policies for onshore wind energy and local dissatisfaction - insights from regulation theory

    Energy Technology Data Exchange (ETDEWEB)

    Parkhill, Karen [School of Psychology, Tower Building, Cardiff University, Cardiff, (United Kingdom)

    2007-09-15

    Although best described as a meta theory addressing the endurance of capitalism, regulation theory can successfully be used to explore not only the economic dimensions, but also the political, socio-cultural and environmental dimensions of particular developmental strategies. Thus, it offers a framework for embedding abstract debates about social attitudes to new technologies within debates about real regulation - the economic, social and cultural relationships operating through particular places. This paper uses regulation theory and qualitative, interview-based data to analyse Scotland's drive for onshore wind energy. This approach teases out how responses to wind farms are bound up with wider debates about how rural spaces are, and should be, regulated; the tensions within and between national political objectives, local political objectives and local communities' dissatisfaction; and the connections between local actors and more formal dimensions of renewable energy policy. (Author)

  7. The UTRC wind energy conversion system performance analysis for horizontal axis wind turbines (WECSPER)

    Science.gov (United States)

    Egolf, T. A.; Landgrebe, A. J.

    1981-01-01

    The theory for the UTRC Energy Conversion System Performance Analysis (WECSPER) for the prediction of horizontal axis wind turbine performance is presented. Major features of the analysis are the ability to: (1) treat the wind turbine blades as lifting lines with a prescribed wake model; (2) solve for the wake-induced inflow and blade circulation using real nonlinear airfoil data; and (3) iterate internally to obtain a compatible wake transport velocity and blade loading solution. This analysis also provides an approximate treatment of wake distortions due to tower shadow or wind shear profiles. Finally, selected results of internal UTRC application of the analysis to existing wind turbines and correlation with limited test data are described.

  8. Impact of Wind Shear and Tower Shadow Effects on Power System with Large Scale Wind Power Penetration

    OpenAIRE

    Hu, Weihao; Su, Chi; Chen, Zhe

    2011-01-01

    Grid connected wind turbines are fluctuating power sources due to wind speed variations, the wind shear and the tower shadow effects. The fluctuating power may be able to excite the power system oscillation at a frequency close to the natural oscillation frequency of a power system. This paper presents a simulation model of a variable speed wind farm with permanent magnet synchronous generators (PMSGs) and fullscale back-to-back converters in the simulation tool of DIgSILENT/PowerFactory. In ...

  9. PV-Wind System with Fuel Cell & Electrolyzer

    Directory of Open Access Journals (Sweden)

    Deepa Sharma

    2015-12-01

    Full Text Available In this paper, a detailed modeling and simulation of solar cell/ wind turbine/ fuel cell hybrid power system is developed using a novel topology to complement each other and to alleviate the effects of environmental variations. Comparing with the other sources , the renewable energy is inexhaustible and has non-pollution characteristics. The solar energy, wind power, hydraulic power and tidal energy are natural resources of the interest to generate electrical power. As the wind turbine output power varies with the wind speed and the solar cell output power varies with both the ambient temperature and radiation, a fuel cell with ultra capacitor bank can be integrated to ensure that the system performs under all conditions. Excess wind and solar energies when available are converted to hydrogen using electrolysis for later use in the fuel cell. In this paper dynamic modeling of various components of this isolated system system is presented. Transient responses of the system to step change in the load, ambient temperature, radiation, and wind speed in a number of possible situations are studied. Modeling and simulations are conducted using MATLAB/Simulink software packages to verify the effectiveness of the proposed system. The results show that the proposed hybrid power system can tolerate the rapid change in natural conditions and suppress the effects of these fluctuations on the voltage within the acceptable range.The proposed system can be used for off grid power generation in non interconnected areas or remote isolated communities of nation.

  10. Performance optimization for doubly fed wind power generation systems

    Energy Technology Data Exchange (ETDEWEB)

    Bhowmik, S.; Spee, R.; Enslin, J.H.R.

    1999-08-01

    Significant variation of the resource kinetic energy, in the form of wind speed, results in substantially reduced energy capture in a fixed-speed wind turbine. In order to increase the wind energy capture in the turbine, variable-speed generation (VSG) strategies have been proposed and implemented. However, that requires an expensive ac/ac power converter, which increases the capital investment significantly. Consequently, doubly fed systems have been proposed to reduce the size of the power converter and, thereby, the associated cost. Additionally, in doubly fed systems, as a fixed operating point (power and speed), power flow can be regulated between the two winding systems on the machine. This feature can by utilized to essentially minimize losses in the machine associated with the given operating point or achieve other desired performance enhancements. In this paper, a brushless doubly fed machine (BDFM) is utilized to develop a VSG wind power generator. The VSG controller employs a wind-speed-estimation-based maximum power point tracker and a heuristic-model-based maximum efficiency point tracker to optimize the power output of the system. The controller has been verified for efficacy on a 1.5-kW laboratory VSG wind generator. The strategy is applicable to all doubly fed configurations, including conventional wound-rotor induction machines, Scherbius cascades, BDFM's and doubly fed reluctance machines.

  11. Future on Power Electronics for Wind Turbine Systems

    DEFF Research Database (Denmark)

    Blaabjerg, Frede; Ma, Ke

    2013-01-01

    generators, power electronic systems, and control solutions have to be introduced to improve the characteristics of the wind power plant and make it more suitable to be integrated into the power grid. Meanwhile, there are also some emerging technology challenges, which need to be further clarified...... and investigated. This paper gives an overview and discusses some development trends in the technologies used for wind power systems. First, the developments of technology and market are generally discussed. Next, several state-of-the-art wind turbine concepts, as well as the corresponding power electronic...

  12. Isolated systems with wind power. An implementation guideline

    DEFF Research Database (Denmark)

    Clausen, Niels-Erik; Bindner, Henrik W.; Frandsen, Sten Tronæs

    2001-01-01

    The overall objective of this research project is to study the development of methods and guidelines rather than "universal solutions" for the use of wind energy in isolated communities. So far most studies of isolated systems with wind power have beencase-oriented and it has proven difficult...... feasibility of isolated power supply systems with wind energy. General guidelines and checklists on which facts and data are needed to carry out a projectfeasibility analysis are presented as well as guidelines how to carry out the project feasibility study and the environmental analysis. The report outlines...

  13. Modeling and Simulation Multi Motors Web Winding System

    Directory of Open Access Journals (Sweden)

    Hachemi Glaoui

    2013-03-01

    Full Text Available Web winding systems allow the operations of unwinding and rewinding of various products including plastic films, sheets of paper, sheets, and fabrics. These operations are necessary for the development and the treatment of these products. Web winding systems generally consist of the same machine elements in spite of the diversity of the transported products. Due to the wide rang variation of the radius and inertia of the rollers the system dynamic change considerably during the winding/ unwinding process. Decentralized PI controller for web tension control and linear speed control are presented in this paper. The PI control method can be applied easily and is widely known, it has an important place in control applications. Simulation results show the effectiveness of the proposed linear speed and tension controller for web winding multi motors systems.

  14. Wind hybrid electrical supply system: behaviour simulation and sizing optimization

    Science.gov (United States)

    Notton, G.; Cristofari, C.; Poggi, P.; Muselli, M.

    2001-04-01

    Using a global approach, a wind hybrid system operation is simulated and the evolution of several parameters is analysed, such as the wasted energy, the fuel consumption and the role of the wind turbine subsystem in the global production. This analysis shows that all the energies which take part in the system operation are more dependent on the wind turbine size than on the battery storage capacity. A storage of 2 or 3 days is sufficient, because an increase in storage beyond these values does not have a notable impact on the performance of the wind hybrid system. Finally, a cost study is performed to determine the optimal configuration of the system conducive to the lowest cost of electricity production.

  15. Transient stability risk assessment of power systems incorporating wind farms

    DEFF Research Database (Denmark)

    Miao, Lu; Fang, Jiakun; Wen, Jinyu;

    2013-01-01

    Large-scale wind farm integration has brought several aspects of challenges to the transient stability of power systems. This paper focuses on the research of the transient stability of power systems incorporating with wind farms by utilizing risk assessment methods. The detailed model of double...... fed induction generator has been established. Wind penetration variation and multiple stochastic factors of power systems have been considered. The process of transient stability risk assessment based on the Monte Carlo method has been described and a comprehensive risk indicator has been proposed....... An investigation has been conducted into an improved 10-generator 39-bus system with a wind farm incorporated to verify the validity and feasibility of the risk assessment method proposed....

  16. WIND TURBINE DRIVETRAIN TEST FACILITY DATA ACQUISITION SYSTEM

    Energy Technology Data Exchange (ETDEWEB)

    Mcintosh, J.

    2012-01-03

    The Wind Turbine Drivetrain Test Facility (WTDTF) is a state-of-the-art industrial facility used for testing wind turbine drivetrains and generators. Large power output wind turbines are primarily installed for off-shore wind power generation. The facility includes two test bays: one to accommodate turbine nacelles up to 7.5 MW and one for nacelles up to 15 MW. For each test bay, an independent data acquisition system (DAS) records signals from various sensors required for turbine testing. These signals include resistance temperature devices, current and voltage sensors, bridge/strain gauge transducers, charge amplifiers, and accelerometers. Each WTDTF DAS also interfaces with the drivetrain load applicator control system, electrical grid monitoring system and vibration analysis system.

  17. ATM Systems In Nigerian Banks: The Wind Of Change | Agundu ...

    African Journals Online (AJOL)

    ATM Systems In Nigerian Banks: The Wind Of Change. ... widespread application of automated teller machines (ATMs) in some top-ranking banks in Nigeria. ... It is however imperative that inherent technology/operations risks be effectively ...

  18. Study of local winds over Tehran using WRF in ideal conditions

    Directory of Open Access Journals (Sweden)

    I Soltanzadeh

    2011-09-01

    Full Text Available   Wind is the carrier of pollutants and any other gaseous or particle matters in the atmosphere. Stable atmosphere with low wind provides favourable conditions for high contamination of pollutants in urban areas. The importance of mesoscale atmospheric flows in air pollution dispersion has been recognized in the past three decades and has been the focus of intensive research; both observational and numerical. Mesoscale or local scale circulations are more prominent when the synoptic pressure gradients are weak, allowing horizontal temperature contrasts to develop, which in turn lead to mesoscale pressure perturbations. Tehran, a city which is situated at the southern foothills of the Alborz Mountain chain has an average elevation of 1500m, and covers an area of 864 km2. Alborz Mountains have a significant influence on the dynamics and thermodynamic modification of wind regime over the city. At the same time, the Urban Heat Island effect (UHI can cause its own mesoscale flow, complicating an already complex local scale flow. The topography and the urban fabric can cause slope flows, mountain flows, and valley flows amongst many other factors. Th is paper focuses on the use of state-of-the-art atmospheric numerical model – The Weather Research and Forecasting (WRF – in an ideal situation to study the characteristics of the mesoscale flow systems that prevail over Tehran when air quality is unfavourable. So average sound of Radiosonde at Mehrabad station, for almost all the fair days of cold seasons from 2005 to 2008 was selected as an ideal initial condition and boundary condition with 10 × 10 km spatial and 12-hour temporal resolution. The simulations were carried out for a 3-day period in December 2005 when an aircraft , due to low visibility caused by high concentration of air pollution, crashed 2 miles away from the end of runway into an inhabited area. Three simulations were prepared. For the first experiment, called control run, we

  19. From technology transfer to local manufacturing: China's emergence in the global wind power industry

    Science.gov (United States)

    Lewis, Joanna Ingram

    This dissertation examines the development of China's large wind turbine industry, including the players, the status of the technology, and the strategies used to develop turbines for the Chinese market. The primary goals of this research project are to identify the models of international technology transfer that have been used among firms in China's wind power industry; examine to what extent these technology transfers have contributed to China's ability to locally manufacture large wind turbine technology; and evaluate China's ability to become a major player in the global wind industry. China is a particularly important place to study the opportunities for and dynamics of clean energy development due to its role in global energy consumption. China is the largest coal consuming and producing nation in the world, and consequently the second largest national emitter of carbon dioxide after only the United States. Energy consumption and carbon emissions are growing rapidly, and China is expected to surpass the US and become the largest energy consuming nation and carbon dioxide emitter in coming decades. The central finding of this dissertation is that even though each firm involved in the large wind turbine manufacturing industry in China has followed a very different pathway of technology procurement for the Chinese market, all of the firms are increasing the utilization of locally-manufactured components, and many are doing so without transferring turbine technology or the associated intellectual property. Only one fully Chinese-owned firm, Goldwind, has succeeded in developing a commercially available large wind turbine for the Chinese market. No Chinese firms or foreign firms are manufacturing turbines in China for export overseas, though many have stated plans to do so. There already exists a possible niche market for the smaller turbines that are currently being made in China, particularly in less developed countries that are looking for less expensive

  20. Revising the Local Bubble Model due to Solar Wind Charge Exchange X-ray Emission

    CERN Document Server

    Shelton, Robin L

    2008-01-01

    The hot Local Bubble surrounding the solar neighborhood has been primarily studied through observations of its soft X-ray emission. The measurements were obtained by attributing all of the observed local soft X-rays to the bubble. However, mounting evidence shows that the heliosphere also produces diffuse X-rays. The source is solar wind ions that have received an electron from another atom. The presence of this alternate explanation for locally produced diffuse X-rays calls into question the existence and character of the Local Bubble. This article addresses these questions. It reviews the literature on solar wind charge exchange (SWCX) X-ray production, finding that SWCX accounts for roughly half of the observed local 1/4 keV X-rays found at low latitudes. This article also makes predictions for the heliospheric O VI column density and intensity, finding them to be smaller than the observational error bars. Evidence for the continued belief that the Local Bubble contains hot gas includes the remaining local...

  1. Dynamic wind turbine models in power system simulation tool

    DEFF Research Database (Denmark)

    Hansen, A.; Jauch, Clemens; Soerensen, P.

    The present report describes the dynamic wind turbine models implemented in the power system simulation tool DIgSILENT. The developed models are a part of the results of a national research project, whose overall objective is to create a model database in different simulation tools. The report...... provides a description of the wind turbine modelling, both at a component level and at a system level....

  2. Supernova feedback in a local vertically stratified medium: interstellar turbulence and galactic winds

    CERN Document Server

    Martizzi, Davide; Faucher-Giguere, Claude-Andre; Quataert, Eliot

    2016-01-01

    We use local Cartesian simulations with a vertical gravitational potential to study how supernova (SN) feedback in stratified galactic discs drives turbulence and launches galactic winds. Our analysis includes three disc models with gas surface densities ranging from Milky Way-like galaxies to gas-rich ultra-luminous infrared galaxies (ULIRGs), and two different SN driving schemes (random and correlated with local gas density). In order to isolate the physics of SN feedback, we do not include additional feedback processes. We find that, in these local box calculations, SN feedback excites relatively low mass-weighted gas turbulent velocity dispersions ~3-7 km/s and low wind mass loading factors <1 in all the cases we study. The low turbulent velocities and wind mass loading factors predicted by our local box calculations are significantly below those suggested by observations of gas-rich and rapidly star-forming galaxies; they are also in tension with global simulations of disc galaxies regulated by stella...

  3. Identifying predictors of attitudes towards local onshore wind development with reference to an English case study

    Energy Technology Data Exchange (ETDEWEB)

    Jones, Christopher R.; Eiser, J. Richard [Department of Psychology, University of Sheffield, Western Bank, Sheffield S10 2TP (United Kingdom)

    2009-11-15

    The threats posed by climate change are placing governments under increasing pressure to meet electricity demand from low-carbon sources. In many countries, including the UK, legislation is in place to ensure the continued expansion of renewable energy capacity. Onshore wind turbines are expected to play a key role in achieving these aims. However, despite high levels of public support for onshore wind development in principle, specific projects often experience local opposition. Traditionally this difference in general and specific attitudes has been attributed to NIMBYism (not in my back yard), but evidence is increasingly calling this assumption into question. This study used multiple regression analysis to identify what factors might predict attitudes towards mooted wind development in Sheffield, England. We report on the attitudes of two groups; one group (target) living close to four sites earmarked for development and an unaffected comparison group (comparison). We found little evidence of NIMBYism amongst members of the target group; instead, differences between general and specific attitudes appeared attributable to uncertainty regarding the proposals. The results are discussed with respect to literature highlighting the importance of early, continued and responsive community involvement in combating local opposition and facilitating the deployment of onshore wind turbines. (author)

  4. Wind Tunnel Management and Resource Optimization: A Systems Modeling Approach

    Science.gov (United States)

    Jacobs, Derya, A.; Aasen, Curtis A.

    2000-01-01

    Time, money, and, personnel are becoming increasingly scarce resources within government agencies due to a reduction in funding and the desire to demonstrate responsible economic efficiency. The ability of an organization to plan and schedule resources effectively can provide the necessary leverage to improve productivity, provide continuous support to all projects, and insure flexibility in a rapidly changing environment. Without adequate internal controls the organization is forced to rely on external support, waste precious resources, and risk an inefficient response to change. Management systems must be developed and applied that strive to maximize the utility of existing resources in order to achieve the goal of "faster, cheaper, better". An area of concern within NASA Langley Research Center was the scheduling, planning, and resource management of the Wind Tunnel Enterprise operations. Nine wind tunnels make up the Enterprise. Prior to this research, these wind tunnel groups did not employ a rigorous or standardized management planning system. In addition, each wind tunnel unit operated from a position of autonomy, with little coordination of clients, resources, or project control. For operating and planning purposes, each wind tunnel operating unit must balance inputs from a variety of sources. Although each unit is managed by individual Facility Operations groups, other stakeholders influence wind tunnel operations. These groups include, for example, the various researchers and clients who use the facility, the Facility System Engineering Division (FSED) tasked with wind tunnel repair and upgrade, the Langley Research Center (LaRC) Fabrication (FAB) group which fabricates repair parts and provides test model upkeep, the NASA and LARC Strategic Plans, and unscheduled use of the facilities by important clients. Expanding these influences horizontally through nine wind tunnel operations and vertically along the NASA management structure greatly increases the

  5. 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

    (WPP) equipped with a WPP voltage controller and comparisons are presented. The models of wind turbine and WPP voltage controller are kindly provided by Siemens Wind Power A/S for this work. The study is based on modal analysis which are complemented with simulations on the nonlinear system.......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...

  6. Wind energy conversion. Volume IV. Drive system dynamics

    Energy Technology Data Exchange (ETDEWEB)

    Martinez-Sanchez, M.; Labuszewski, T.

    1978-09-01

    The dynamics of the drive system and various approaches to power transmission are described. The effects on performance of using a constant rotor speed as opposed to a rotor speed varying with the wind speed are discussed for various rotor operating schedules and typical wind distributions. The dynamics of the combined rotor, alternator, and drive system are analyzed. Conditions which could lead to electro-dynamic instabilities and desynchronization are discussed as well as means for stabilizing the system. The dynamics of the drive system and important design conditions for various drive systems are discussed, such as location of the alternators, use of hydraulic drive systems and smoothing techniques.

  7. Optimal Sizing of wind power systems in three high wind potential zones in Kuwait for remote housing electrification

    OpenAIRE

    Hajiah, Ali; M. Sebzali

    2016-01-01

    This paper presents a technical study for wind power systems in three sites in Kuwait namely Al-Wafra, Um-Omara and Al-Taweel. Hourly wind speed data for three years are used in order to optimally sizing the wind power systems. Firstly, the Wiebull, function is used to model the wind speed data for each sites. After that a numerical method is used to optimize the energy sources in the power system (wind turbine and battery) using MATLAB. After that the MATLAB is used to analyze the performanc...

  8. Grid Converters for Photovoltaic and Wind Power Systems

    DEFF Research Database (Denmark)

    Teodorescu, Remus; Liserre, Marco; Rodriguez, Pedro

    power, operation within a wide range of voltage and frequency, voltage ride-through capability, reactive current injection during faults, grid services support. This book explains the topologies, modulation and control of grid converters for both photovoltaic and wind power applications. In addition...... to power electronics, this book focuses on the specific applications in photovoltaic wind power systems where grid condition is an essential factor. With a review of the most recent grid requirements for photovoltaic and wind power systems, the book discusses these other relevant issues: Modern grid...... inverter topologies for photovoltaic and wind turbines Islanding detection methods for photovoltaic systems Synchronization techniques based on second order generalized integrators (SOGI) Advanced synchronization techniques with robust operation under grid unbalance condition grid filter design and active...

  9. Noise source localization using Matched Field Processing: wind turbines, mofettes and geysirs.

    Science.gov (United States)

    Umlauft, Josefine; Flores Estrella, Hortencia; Christin Obermann, Anne; Korn, Michael

    2017-04-01

    The Matched Field Processing (MFP) is a beamforming method, derived from ocean acoustics, that serves as a noise source localization and exploration tool in applied geophysics. Here, we present three case studies to explore the applicability of MFP in the presence of different source types, and using sensor arrays with different aperture and density. First, we show the localization of a single wind turbine (Saxony, Eastern Germany), which acts as a point source at the surface generating continuous vibrations due to the rotation of their blades. Using 30 vertical sensors (Reftek Texans) randomly distributed within an area of approximately 50 x 50 m2 around the wind turbine, we identified the turbine as the dominant noise source within the array. Therefore we verified that the MFP procedure gives useful results. The second test was performed in Hartouŝov (NW Bohemia, Czech Republic). This area is characterized by several natural degassing areas of mantle-originating fluids and CO2 (mofettes). Mofettes either appear as little sinks filled with bubbling groundwater or more extensive as vegetation anomalies. We located these mofettes, using the collapsing water bubbles as seismic noise source, and compared our results with CO2 flux values of the same field measured by Nickschick et al. (2015). The array consisted of 130 stations in total (30 Reftek Texans, 50 Omnirecs Data-Cubes3 and 50 Summit X-One channels) and covered an area of about 500 x 1000 m2. Additionally to MFP, we perfomed a polarization analysis of surface waves to characterize the wave field generated by the the degassing process. The last example is a geysering system in NE Java (Indonesia) which is called LUSI (Lumpur Sidoarjo). The geysir was surrounded by 5 stations (Trillium Compacts) arranged in a circle with about 1.5 km diameter. Here, we could successfully locate the surface position of the geysir as well as image its feeding channel to a depth of 100 m. This example shows the suitability of MFP

  10. Local fatigue behavior in tapered areas of large offshore wind turbine blades

    Science.gov (United States)

    Aydin Raeis Hosseiny, Seyed; Jakobsen, Johnny

    2016-07-01

    Thickness transitions in load carrying elements lead to improved geometries and efficient material utilization. However, these transitions may introduce localized areas with high stress concentrations and may act as crack initiators that could potentially cause delamination and further catastrophic failure of an entire blade structure. The local strength degradation under an ultimate static loading, subsequent to several years of fatigue, is predicted for an offshore wind turbine blade. Fatigue failure indexes of different damage modes are calculated using a sub-modeling approach. Multi axial stresses are accounted for using a developed failure criterion with residual strengths instead of the virgin strengths. Damage initiation is predicted by including available Wohler curve data of E-Glass fabrics and epoxy matrix into multi-axial fatigue failure criteria. As a result of this study, proper knock-down factors for ply-drop effects in wind turbine blades under multi-axial static and fatigue loadings can be obtained.

  11. Nose in the wind. Sensors for angles and pathways in wind power systems; Mit der Nase gegen den Wind. Sensorik fuer Winkel und Wege in Windkraftanlagen

    Energy Technology Data Exchange (ETDEWEB)

    Anon.

    2006-07-01

    For an optimum performance of wind power systems, the nacelle and rotor blades must be adjusted to the wind direction and wind speed. Angle coding sensors on each rotor blade provide information on the current position; their signals are taken into account for readjustment. Further angle sensors define the wind direction and the nacelle position. The high requirements made on availability and life of wind power systems require reliable measuring probes which provide accurate and undisturbed signals even in the rough weather conditions of extreme climate zones. (orig.)

  12. Adaptive Controller for Drive System PMSG in Wind Turbine

    Directory of Open Access Journals (Sweden)

    Gnanambal

    2014-07-01

    Full Text Available This paper proposes adaptive Maximum Power Point Tracking (MPPT controller for Permanent Magnet Synchronous Generator (PMSG wind turbine and direct power control for grid side inverter for transformer less integration of wind energy. PMSG wind turbine with two back to back voltage source converters are considered more efficient, used to make real and reactive power control. The optimal control strategy has introduced for integrated control of PMSG Maximum Power Extraction, DC link voltage control and grid voltage support controls. Simulation model using MATLAB Simulink has developed to investigate the performance of proposed control techniques for PMSG wind turbine steady and variable wind conditions. This paper shows that the direct driven grid connected PMSG system has excellent performances and confirms the feasibility of the proposed techniques. While the wind turbine market continues to be dominated by conventional gear-driven wind turbine systems, the direct drive is attracting attention. PM machines are more attractive and superior with higher efficiency and energy yield, higher reliability, and power-to-weight ratio compared with electricity-excited machines.

  13. Proposed Wind Turbine Aeroelasticity Studies Using Helicopter Systems Analysis

    Science.gov (United States)

    Ladkany, Samaan G.

    1998-01-01

    Advanced systems for the analysis of rotary wing aeroelastic structures (helicopters) are being developed at NASA Ames by the Rotorcraft Aeromechanics Branch, ARA. The research has recently been extended to the study of wind turbines, used for electric power generation Wind turbines play an important role in Europe, Japan & many other countries because they are non polluting & use a renewable source of energy. European countries such as Holland, Norway & France have been the world leaders in the design & manufacture of wind turbines due to their historical experience of several centuries, in building complex wind mill structures, which were used in water pumping, grain grinding & for lumbering. Fossil fuel cost in Japan & in Europe is two to three times higher than in the USA due to very high import taxes. High fuel cost combined with substantial governmental subsidies, allow wind generated power to be competitive with the more traditional sources of power generation. In the USA, the use of wind energy has been limited mainly because power production from wind is twice as expensive as from other traditional sources. Studies conducted at the National Renewable Energy Laboratories (NREL) indicate that the main cost in the production of wind turbines is due to the materials & the labor intensive processes used in the construction of turbine structures. Thus, for the US to assume world leadership in wind power generation, new lightweight & consequently very flexible wind turbines, that could be economically mass produced, would have to be developed [4,5]. This effort, if successful, would result in great benefit to the US & the developing nations that suffer from overpopulation & a very high cost of energy.

  14. IMPRINTS OF EXPANSION ON THE LOCAL ANISOTROPY OF SOLAR WIND TURBULENCE

    Energy Technology Data Exchange (ETDEWEB)

    Verdini, Andrea [Dipartimento di fisica e astronomia, Università di Firenze, Firenze (Italy); Grappin, Roland [LPP, Ecole Polytechnique, Palaiseau (France)

    2015-08-01

    We study the anisotropy of II-order structure functions (SFs) defined in a frame attached to the local mean field in three-dimensional (3D) direct numerical simulations of magnetohydrodynamic turbulence, with the solar wind expansion both included and not included. We simulate spacecraft flybys through the numerical domain by taking increments along the radial (wind) direction that form an angle of 45° with the ambient magnetic field. We find that only when expansion is taken into account do the synthetic observations match the 3D anisotropy observed in the solar wind, including the change of anisotropy with scale. Our simulations also show that the anisotropy changes dramatically when considering increments oblique to the radial directions. Both results can be understood by noting that expansion reduces the radial component of the magnetic field at all scales, thus confining fluctuations in the plane perpendicular to the radial. Expansion is thus shown to affect not only the (global) spectral anisotropy, but also the local anisotropy of second-order SF by influencing the distribution of the local mean field, which enters this higher-order statistics.

  15. System-wide emissions implications of increased wind power penetration.

    Science.gov (United States)

    Valentino, Lauren; Valenzuela, Viviana; Botterud, Audun; Zhou, Zhi; Conzelmann, Guenter

    2012-04-03

    This paper discusses the environmental effects of incorporating wind energy into the electric power system. We present a detailed emissions analysis based on comprehensive modeling of power system operations with unit commitment and economic dispatch for different wind penetration levels. First, by minimizing cost, the unit commitment model decides which thermal power plants will be utilized based on a wind power forecast, and then, the economic dispatch model dictates the level of production for each unit as a function of the realized wind power generation. Finally, knowing the power production from each power plant, the emissions are calculated. The emissions model incorporates the effects of both cycling and start-ups of thermal power plants in analyzing emissions from an electric power system with increasing levels of wind power. Our results for the power system in the state of Illinois show significant emissions effects from increased cycling and particularly start-ups of thermal power plants. However, we conclude that as the wind power penetration increases, pollutant emissions decrease overall due to the replacement of fossil fuels.

  16. Wind Turbine Blade Nondestructive Testing with a Transportable Radiography System

    Directory of Open Access Journals (Sweden)

    J. G. Fantidis

    2011-01-01

    Full Text Available Wind turbines are becoming widely used as they are an environmentally friendly way for energy production without emissions; however, they are exposed to a corrosive environment. In addition, as wind turbines typically are the tallest structures in the surrounding area of a wind farm, it is expected that they will attract direct lightning strikes several times during their operating life. The purpose of this paper is to show that the radiography with a transportable unit is a solution to find defects in the wind turbine blade and reduce the cost of inspection. A transportable neutron radiography system, incorporating an Sb–Be source, has been simulated using the MCNPX code. The simulated system has a wide range of radiography parameters.

  17. LCA of electricity systems with high wind power penetration

    DEFF Research Database (Denmark)

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

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

  18. Integrated Bidding and Operating Strategies for Wind-Storage Systems

    DEFF Research Database (Denmark)

    Ding, Huajie; Pinson, Pierre; Hu, Zechun

    2016-01-01

    to perform arbitrage and to alleviate wind power deviations from day-ahead contracts. The strategy is developed with two-price balancing markets in mind. A mixed integer nonlinear optimization formulation is built to determine optimal offers by taking into account expected wind power forecasting errors......Due to their flexible charging and discharging capabilities, energy storage systems (ESS) are considered a promising complement to wind farms (WFs) participating in electricity markets. This paper presents integrated day-ahead bidding and real-time operation strategies for a wind-storage system...... and the power balancing capability of the ESS. A modified gradient descent algorithm is designed to solve this nonlinear problem. A number of case studies validate the computational efficiency and optimality of the algorithm. Compared to the existing strategies, the proposed strategies yield increased economic...

  19. Model predictive control of wind energy conversion systems

    CERN Document Server

    Yaramasu, Venkata Narasimha R

    2017-01-01

    The authors provide a comprehensive analysis on the model predictive control of power converters employed in a wide variety of variable-speed wind energy conversion systems (WECS). The contents of this book includes an overview of wind energy system configurations, power converters for variable-speed WECS, digital control techniques, MPC, modeling of power converters and wind generators for MPC design. Other topics include the mapping of continuous-time models to discrete-time models by various exact, approximate, and quasi-exact discretization methods, modeling and control of wind turbine grid-side two-level and multilevel voltage source converters. The authors also focus on the MPC of several power converter configurations for full variable-speed permanent magnet synchronous generator based WECS, squirrel-cage induction generator based WECS, and semi-variable-speed doubly fed induction generator based WECS.

  20. Automatic Voltage Control (AVC) System under Uncertainty from Wind Power

    DEFF Research Database (Denmark)

    Qin, Nan; Abildgaard, Hans; Flynn, Damian

    2016-01-01

    An automatic voltage control (AVC) system maintains the voltage profile of a power system in an acceptable range and minimizes the operational cost by coordinating the regulation of controllable components. Typically, all of the parameters in the optimization problem are assumed to be certain...... and constant in the decision making process. However, for high shares of wind power, uncertainty in the decision process due to wind power variability may result in an infeasible AVC solution. This paper proposes a voltage control approach which considers the voltage uncertainty from wind power productions....... The proposed method improves the performance and the robustness of a scenario based approach by estimating the potential voltage variations due to fluctuating wind power production, and introduces a voltage margin to protect the decision against uncertainty for each scenario. The effectiveness of the proposed...

  1. Feedback Linearization Controller for a Wind Energy Power System

    Directory of Open Access Journals (Sweden)

    Muthana Alrifai

    2016-09-01

    Full Text Available This paper deals with the control of a doubly-fed induction generator (DFIG-based variable speed wind turbine power system. A system of eight ordinary differential equations is used to model the wind energy conversion system. The generator has a wound rotor type with back-to-back three-phase power converter bridges between its rotor and the grid; it is modeled using the direct-quadrature rotating reference frame with aligned stator flux. An input-state feedback linearization controller is proposed for the wind energy power system. The controller guarantees that the states of the system track the desired states. Simulation results are presented to validate the proposed control scheme. Moreover, further simulation results are shown to investigate the robustness of the proposed control scheme to changes in some of the parameters of the system.

  2. Electricity for road transport, flexible power systems and wind power

    Energy Technology Data Exchange (ETDEWEB)

    Nielsen, Lars Henrik; Ravn, H.; Meibom, P. (and others)

    2011-12-15

    The aim of the project is to analyse the potential synergistic interplay that may arise between the power sector and the transport sector, if parts of the road transport energy needs are based on electricity via the utilisation of plug-in hybrid electric vehicles and pure electric vehicles. The project focuses on the technical elements in the chain that comprises: 1: The electric vehicle status, potentials and expected development. Electric batteries are in focus in this part of the analysis. 2: Analysis of plug-in hybrid electric vehicle interacting with a local grid. 3: Analysis of grid-vehicle connection systems including technical regulation options and analysis of needs for standardisation. 4: Setting up scenarios covering potential developments for utilizing electric drive trains in road transport. Period: Up to year 2030. 5: Analysis of capacity constraints in the electricity grid (transmission and distribution) as consequence of increasing electricity demand, and new flexible consumption patterns from segments in the transport sector, and as consequence of increasing capacity on wind power in the system. 6: Setting up and analysis of combined scenarios covering both the heat and power system and the transport sector. (Author)

  3. Power Electronics and Controls for Wind Turbine Systems

    DEFF Research Database (Denmark)

    Blaabjerg, Frede; Iov, Florin; Chen, Zhe

    2010-01-01

    term) based energy sources to renewable energy sources. Another is to use power electronics to achieve high efficiency in power generation, transmission/distribution and utilization. This paper discuss trends of the most promising renewable energy sources, wind energy, which ,integrated with power...... electronics, is changing the future electrical infrastructure and also contributes steadily to non-carbon based electricity production. The paper’s focus is on the power electronics technologies used in wind turbine systems....

  4. Sizing PV-wind hybrid energy system for lighting

    Directory of Open Access Journals (Sweden)

    Mustafa Engin

    2012-09-01

    Full Text Available Sizing of wind and photovoltaic generators ensures lower operational costs and therefore, is considered as an important issue. An approach for sizing along with a best management technique for a PV-wind hybrid system with batteries is proposed in this paper, in which the best size for every component of the system could be optimized according to the weather conditions and the load profile. The average hourly values for wind speed and solar radiation for Izmir, Turkey has been used in the design of the systems, along with expected load profile. A hybrid power model is also developed for battery operation according to the power balance between generators and loads used in the software, to anticipate performances for the different systems according to the different weather conditions. The output of the program will display the performance of the system during the year, the total cost of the system, and the best size for the PV-generator, wind generator, and battery capacity. Using proposed procedure, a 1.2 kWp PV-wind hybrid system was designed for Izmir, and simulated and measured results are presented.

  5. Comparative Study Between Wind and Photovoltaic (PV) Systems

    Science.gov (United States)

    Taha, Wesam

    This paper reviews two renewable energy systems; wind and photovoltaic (PV) systems. The common debate between the two of them is to conclude which one is better, in terms of cost and efficiency. Therefore, comparative study, in terms of cost and efficiency, is attempted. Regarding total cost of both, wind and PV systems, many parameters must be taken into consideration such as availability of energy (either wind or solar), operation and maintenance, availability of costumers, political influence, and the components used in building the system. The main components and parameters that play major role in determining the overall efficiency of wind systems are the wind turbine generator (WTG), gearbox and control technologies such as power, and speed control. On the other hand, in grid-connected PV systems (GCPVS), converter architecture along with maximum power point tracking (MPPT) algorithm and inverter topologies are the issues that affects the efficiency significantly. Cost and efficiency analyses of both systems have been carried out based on the statistics available till today and would be useful in the progress of renewable energy penetration throughout the world.

  6. Sizing and Simulation of PV-Wind Hybrid Power System

    Directory of Open Access Journals (Sweden)

    Mustafa Engin

    2013-01-01

    Full Text Available A sizing procedure is developed for hybrid system with the aid of mathematical models for photovoltaic cell, wind turbine, and battery that are readily present in the literature. This sizing procedure can simulate the annual performance of different kinds of photovoltaic-wind hybrid power system structures for an identified set of renewable resources, which fulfills technical limitations with the lowest energy cost. The output of the program will display the performance of the system during the year, the total cost of the system, and the best size for the PV-generator, wind generator, and battery capacity. Security lightning application is selected, whereas system performance data and environmental operating conditions are measured and stored. This hybrid system, which includes a PV, wind turbine, inverter, and a battery, was installed to supply energy to 24 W lamps, considering that the renewable energy resources of this site where the system was installed were 1700 Wh/m2/day solar radiation and 3.43 m/s yearly average wind speed. Using the measured variables, the inverter and charge regulator efficiencies were calculated as 90% and 98%, respectively, and the overall system’s electrical efficiency is calculated as 72%. Life cycle costs per kWh are found to be $0.89 and LLP = 0.0428.

  7. An optimal sizing method for energy storage system in wind farms based on the analysis of wind power forecast error

    Science.gov (United States)

    Ye, R. L.; Guo, Z. Z.; Liu, R. Y.; Liu, J. N.

    2016-11-01

    Energy storage system (ESS) in a wind farm can effectively compensate the fluctuations of wind power. How to determine the size of ESS in wind farms is an urgent problem to be solved. A novel method is proposed for designing the optimal size of ESS considering wind power uncertainty. This approach uses non-parametric estimation method to analysis the wind power forecast error (WPFE) and the cumulative wind power deviation (CWPD) within the scheduling period. Then a cost-benefit analysis model is established to obtain the optimal size of ESS based on the analysis of WPFE and CWPD. A series of wind farm data in California are used as numerical cases, which presents that the algorithm presented in this paper has good feasibility and performance in optimal ESS sizing in wind farms.

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2015-01-01

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

  9. Development of an intelligent hypertext system for wind tunnel testing

    Science.gov (United States)

    Lo, Ching F.; Shi, George Z.; Steinle, Frank W.; Wu, Y. C. L. Susan; Hoyt, W. Andes

    1991-01-01

    This paper summarizes the results of a system utilizing artificial intelligence technology to improve the productivity of project engineers who conduct wind tunnel tests. The objective was to create an intelligent hypertext system which integrates a hypertext manual and expert system that stores experts' knowledge and experience. The preliminary (Phase I) effort implemented a prototype IHS module encompassing a portion of the manuals and knowledge used for wind tunnel testing. The effort successfully demonstrated the feasibility of the intelligent hypertext system concept. A module for the internal strain gage balance, implemented on both IBM-PC and Macintosh computers, is presented. A description of the Phase II effort is included.

  10. Wind turbine generators having wind assisted cooling systems and cooling methods

    Science.gov (United States)

    Bagepalli, Bharat [Niskayuna, NY; Barnes, Gary R [Delanson, NY; Gadre, Aniruddha D [Rexford, NY; Jansen, Patrick L [Scotia, NY; Bouchard, Jr., Charles G.; Jarczynski, Emil D [Scotia, NY; Garg, Jivtesh [Cambridge, MA

    2008-09-23

    A wind generator includes: a nacelle; a hub carried by the nacelle and including at least a pair of wind turbine blades; and an electricity producing generator including a stator and a rotor carried by the nacelle. The rotor is connected to the hub and rotatable in response to wind acting on the blades to rotate the rotor relative to the stator to generate electricity. A cooling system is carried by the nacelle and includes at least one ambient air inlet port opening through a surface of the nacelle downstream of the hub and blades, and a duct for flowing air from the inlet port in a generally upstream direction toward the hub and in cooling relation to the stator.

  11. Towards a Danish power system with 50% wind

    DEFF Research Database (Denmark)

    Xu, Zhao; Gordon, Mark; Lind, Morten;

    2009-01-01

    The new Danish Energy Strategy implies 50% wind power penetration for the Danish electric power system by 2025. Accordingly, it is the vision to develop the Danish electric power system into world's best renewable based electricity system, and many research and development activities have taken...

  12. Offshore wind farms in the local community - a survey at Nysted offshore wind farm. Background report; Havvindmoeller i lokalomraedet - en undersoegelse ved Nysted havmoellepark. Baggrundsrapport

    Energy Technology Data Exchange (ETDEWEB)

    Kuehn, S.

    2005-07-15

    This report is part of a socio-economic project about offshore wind farms' influence on the local community. The project is part of the monitoring programme in connection with the establishment of the offshore wind farms at Horns Rev and Nysted. The socio-economic project consists of a sociological and an environment-economic project. This report is part of the sociological project which has the purpose of identifying attitudes towards the wind farm before and after the erection with a view to identify possible changes in opinions and reasons for these changes. (BA)

  13. Offshore wind farms in the local community - a survey at Horns Rev wind farm. Background report; Havvindmoeller i lokalomraedet - en undersoegelse ved Horns Rev havmoellepark. Baggrundsrapport

    Energy Technology Data Exchange (ETDEWEB)

    Kuehn, S.

    2005-07-15

    This report is part of a socio-economic project about offshore wind farms' influence on the local community. The project is part of the monitoring programme in connection with the establishment of the offshore wind farms at Horns Rev and Nysted. The socio-economic project consists of a sociological and an environment-economic project. This report is part of the sociological project which has the purpose of identifying attitudes towards the wind farm before and after the erection with a view to identify possible changes in opinions and reasons for these changes. (BA)

  14. Massive Stars in Colliding Wind Systems: the GLAST Perspective

    Energy Technology Data Exchange (ETDEWEB)

    Reimer, Anita; Reimer, Olaf; /Stanford U., HEPL /KIPAC, Menlo Park

    2011-11-29

    Colliding winds of massive stars in binary systems are considered as candidate sites of high-energy non-thermal photon emission. They are already among the suggested counterparts for a few individual unidentified EGRET sources, but may constitute a detectable source population for the GLAST observatory. The present work investigates such population study of massive colliding wind systems at high-energy gamma-rays. Based on the recent detailed model (Reimer et al. 2006) for non-thermal photon production in prime candidate systems, we unveil the expected characteristics of this source class in the observables accessible at LAT energies. Combining the broadband emission model with the presently cataloged distribution of such systems and their individual parameters allows us to conclude on the expected maximum number of LAT-detections among massive stars in colliding wind binary systems.

  15. Electric Vehicles in Power Systems with 50% Wind Power Penetration

    DEFF Research Database (Denmark)

    Østergaard, Jacob; Foosnæs, Anders; Xu, Zhao

    2009-01-01

    . This paper analyse the potential for using EVs in Denmark and identify the benefits of the electric power system with high wind power generation by intelligent charging of the EVs. Based on the analysis important technology gabs are identified, and the corresponding research and development initiatives...... will be an important balancing measure to enable the Danish government’s energy strategy, which implies 50% wind power penetration in the electric power system. An EV will be a storage device for smoothing power fluctuations from renewable resources especially wind power and provide valuable system services...... for a reliable power system operation. Cost-benefit analysis shows that intelligent bidirectional charging – vehicle to grid (V2G) – provides a socio-economic profit of 150 million Euro/year in the Danish electric power system in 2025 assuming that 15% of the Danish road transport need is supplied by electricity...

  16. Sociological investigation of the reception of Horns Rev and Nysted offshore wind farms in the local communities[Denmark

    Energy Technology Data Exchange (ETDEWEB)

    Kuehn, S.

    2005-03-15

    This annual report presents the work related to the sociological part of the socio-economic project on the local communities' reception of the Horns Rev Offshore Wind Farm, west of Blaavands Huk in Jutland, and the Nysted Offshore Wind Farm, south of Lolland. The project is part of the monitoring programme in connection with the construction of the offshore wind farms. Unlike projects, which examine the impact of the wind farms on nature, the socio-economic project did not start until 2003. The socio-economic project examines the effects on the local communities. Among other things the environmental-economic part of the project examines the preferences of the population in relation to location of the wind farm and the willingness to pay for increasing the distance between the wind farms and the coast. The sociological survey is qualitative. The survey is divided into three phases, as the aim is to investigate the public community's attitude towards the erection of an offshore wind farm before and after the construction of the wind farm. This aim is based on the assumption that attitudes may change once the wind farm is erected and the population has experienced the visibility of the wind farm, etc. The division into phases is as follows: 1) Phase 1 treats the conditions as they were before the erection of Nysted Offshore Wind Farm. 2) Phase 2 is an investigation of the development in attitudes towards Horns Rev Offshore Wind Farm a year after erection. 3) Phase 3 comprises a follow-up investigation of the local area at Nysted Offshore Wind Farm. This annual report treats phases 1 and 2. Phase 1 was carried out in April-August 2003, and the interviews at Nysted were thus made during the erection of the first offshore wind turbines. Phase 2 was carried out in September-November 2003. The follow-up investigation of the conditions in the local area around Nysted offshore wind farm is to be carried out in August-December 2004. The results of the investigations

  17. Responses of Local Birds to the Offshore Wind Farms PAWP and OWEZ off the Dutch mainland coast

    NARCIS (Netherlands)

    Leopold, M.F.; Bemmelen, van R.S.A.; Zuur, A.F.

    2012-01-01

    Offshore wind turbines are an alien element at sea, a “landscape” that is normally wide and open. Large, turning turbines might affect the local seabirds, that are dependent on the sea. One of the possible effects of offshore wind farms might be that the seabirds will be displaced from the sites, wh

  18. CubeSat Constellation Cloud Winds(C3Winds) A New Wind Observing System to Study Mesoscale Cloud Dynamics and Processes

    Science.gov (United States)

    Wu, D. L.; Kelly, M.A.; Yee, J.-H.; Boldt, J.; Demajistre, R.; Reynolds, E. L.; Tripoli, G. J.; Oman, L. D.; Prive, N.; Heidinger, A. K.; hide

    2016-01-01

    The CubeSat Constellation Cloud Winds (C3Winds) is a NASA Earth Venture Instrument (EV-I) concept with the primary objective to better understand mesoscale dynamics and their structures in severe weather systems. With potential catastrophic damage and loss of life, strong extratropical and tropical cyclones (ETCs and TCs) have profound three-dimensional impacts on the atmospheric dynamic and thermodynamic structures, producing complex cloud precipitation patterns, strong low-level winds, extensive tropopause folds, and intense stratosphere-troposphere exchange. Employing a compact, stereo IR-visible imaging technique from two formation-flying CubeSats, C3Winds seeks to measure and map high-resolution (2 km) cloud motion vectors (CMVs) and cloud geometric height (CGH) accurately by tracking cloud features within 5-15 min. Complementary to lidar wind observations from space, the high-resolution wind fields from C3Winds will allow detailed investigations on strong low-level wind formation in an occluded ETC development, structural variations of TC inner-core rotation, and impacts of tropopause folding events on tropospheric ozone and air quality. Together with scatterometer ocean surface winds, C3Winds will provide a more comprehensive depiction of atmosphere-boundary-layer dynamics and interactive processes. Built upon mature imaging technologies and long history of stereoscopic remote sensing, C3Winds provides an innovative, cost-effective solution to global wind observations with potential of increased diurnal sampling via CubeSat constellation.

  19. An Energy Storage System Sizing Method for Wind Power Integration

    Directory of Open Access Journals (Sweden)

    Wei Wang

    2013-07-01

    Full Text Available Combining an energy storage system (ESS with a wind farm is an effective way to increase the penetration rate of wind power. ESS sizing is an important part in wind farm planning nowadays. In this paper, a basic method for determining the optimal capacity of an ESS integrated with a wind power generator to meet the requirements of grid integration is presented. With the proposed method, the necessary ESS capacity which can provide the best benefits between the regulation effects and energy storage size was calculated. The segmentation method and automatic segmentation method are proposed to improve the performance of the basic method. Further work on expanding the method to determine the necessary capacity of ESS for real-time control is studied. The time window method is used to enable the proposed method available under all working conditions. The simulation results verify the effectiveness of the proposed method.

  20. Conceptual Model of Offshore Wind Environmental Risk Evaluation System

    Energy Technology Data Exchange (ETDEWEB)

    Anderson, Richard M.; Copping, Andrea E.; Van Cleve, Frances B.; Unwin, Stephen D.; Hamilton, Erin L.

    2010-06-01

    In this report we describe the development of the Environmental Risk Evaluation System (ERES), a risk-informed analytical process for estimating the environmental risks associated with the construction and operation of offshore wind energy generation projects. The development of ERES for offshore wind is closely allied to a concurrent process undertaken to examine environmental effects of marine and hydrokinetic (MHK) energy generation, although specific risk-relevant attributes will differ between the MHK and offshore wind domains. During FY10, a conceptual design of ERES for offshore wind will be developed. The offshore wind ERES mockup described in this report will provide a preview of the functionality of a fully developed risk evaluation system that will use risk assessment techniques to determine priority stressors on aquatic organisms and environments from specific technology aspects, identify key uncertainties underlying high-risk issues, compile a wide-range of data types in an innovative and flexible data organizing scheme, and inform planning and decision processes with a transparent and technically robust decision-support tool. A fully functional version of ERES for offshore wind will be developed in a subsequent phase of the project.

  1. 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.

  2. Modeling and Simulation for Hybrid of PV-Wind system

    Directory of Open Access Journals (Sweden)

    Maged N. F. Nashed

    2015-04-01

    Full Text Available The rising consumption rate of fossil fuels causes a significant pollution impact on the atmosphere, unwanted greenhouse gases has drawn worldwide attention towards renewable energy sources. Moreover, in recent year’s generation of electricity using the different types of renewable sources are specifically evaluated in the economical performance of the overall equipment. This paper focuses on the modeling and analysis of a Standalone Photovoltaic (PV- wind energy hybrid generation system under different conditions using MATLAB. The proposed system consists of two renewable sources i.e. wind and solar energy. Modeling of PV array and wind turbine is explained. The wind subsystem is equipped of an induction generator. In photovoltaic system, the variable DC output voltage is controlled using buck-boost converter for the MPPT. These two systems are combined to operate in parallel and the common bus collects the total energy from the wind and PV systems are uses it to the load and with change the load

  3. Fuzzy logic based variable speed wind generation system

    Energy Technology Data Exchange (ETDEWEB)

    Simoes, M.G. [Sao Paulo Univ., SP (Brazil). Escola Politecnica. PMC - Mecatronica; Bose, B.K. [Tennessee Univ., Knoxville, TN (United States). Dept. of Electrical Engineering; Spiegel, Ronal J. [Environmental Protection Agency, Research Triangle Park, NC (United States). Air and Energy Engineering Research Lab.

    1996-12-31

    This work demonstrates the successful application of fuzzy logic to enhance the performance and control of a variable speed wind generation system. A maximum power point tracker control is performed with three fuzzy controllers, without wind velocity measurement, and robust to wind vortex and turbine torque ripple. A squirrel cage induction generator feeds the power to a double-sided PWM converter system which pumps the power to a utility grid or supplies to an autonomous system. The fuzzy logic controller FLC-1 searches on-line the generator speed so that the aerodynamic efficiency of the wind turbine is optimized. A second fuzzy controller FLC-2 programs the machine flux by on-line search so as to optimize the machine-converter system wind vortex. Detailed analysis and simulation studies were performed for development of the control strategy and fuzzy algorithms, and a DSP TMS320C30 based hardware with C control software was built for the performance evaluation of a laboratory experimental set-up. The theoretical development was fully validated and the system is ready to be reproduced in a higher power installation. (author) 7 refs., 3 figs., 1 tab.

  4. Advanced Control of Photovoltaic and Wind Turbines Power Systems

    DEFF Research Database (Denmark)

    Yang, Yongheng; Chen, Wenjie; Blaabjerg, Frede

    2014-01-01

    Much more efforts have been made on the integration of renewable energies into the grid in order to meet the imperative demand of a clean and reliable electricity generation. In this case, the grid stability and robustness may be violated due to the intermittency and interaction of the solar...... and wind renewables. Thus, in this chapter, advanced control strategies, which can enable the power conversion efficiently and reliably, for both photovoltaic (PV) and wind turbines power systems are addressed in order to enhance the integration of those technologies. Related grid demands have been...... power injection for both single-phase and three-phase systems. Other control strategies like constant power generation control for PV systems to further increase the penetration level, and the improvements of LVRT performance for a doubly fed induction generator based wind turbine system by means...

  5. Control design for an autonomous wind based hydrogen production system

    Energy Technology Data Exchange (ETDEWEB)

    Valenciaga, F.; Evangelista, C.A. [CONICET, Laboratorio de Electronica Industrial Control e Instrumentacion (LEICI), Facultad de Ingenieria, Universidad Nacional de La Plata, CC.91, C.P. 1900, La Plata (Argentina)

    2010-06-15

    This paper presents a complete control scheme to efficiently manage the operation of an autonomous wind based hydrogen production system. This system comprises a wind energy generation module based on a multipolar permanent magnet synchronous generator, a lead-acid battery bank as short term energy storage and an alkaline von Hoerner electrolyzer. The control is developed in two hierarchical levels. The higher control level or supervisor control determines the general operation strategy for the whole system according to the wind conditions and the state of charge of the battery bank. On the other hand, the lower control level includes the individual controllers that regulate the respective module operation assuming the set-points determined by the supervisor control. These last controllers are approached using second-order super-twisting sliding mode techniques. The performance of the closed-loop system is assessed through representative computer simulations. (author)

  6. Design of intelligent controllers for wind generation system with sensorless maximum wind energy control

    Energy Technology Data Exchange (ETDEWEB)

    Lin, Whei-Min; Hong, Chih-Ming [Department of Electrical Engineering, National Sun Yat-Sen University, Kaohsiung 80424 (China); Cheng, Fu-Sheng [Department of Electrical Engineering, Cheng-Shiu University, Kaohsiung 83305 (China)

    2011-02-15

    This paper presents the design of an on-line training recurrent fuzzy neural network (RFNN) controller with a high-performance model reference adaptive system (MRAS) observer for the sensorless control of a induction generator (IG). The modified particle swarm optimization (MPSO) is adopted in this study to adapt the learning rates in the back-propagation process of the RFNN to improve the learning capability. By using the proposed RFNN controller with MPSO, the IG system can work for stand-alone power application effectively. The proposed output maximization control is achieved without mechanical sensors such as the wind speed or position sensor, and the new control system will deliver maximum electric power with light weight, high efficiency, and high reliability. The estimation of the rotor speed is based on the MRAS control theory. A sensorless vector-control strategy for an IG operating in a grid-connected variable speed wind energy conversion system can be achieved. (author)

  7. Fiber-Optic Defect and Damage Locator System for Wind Turbine Blades

    Energy Technology Data Exchange (ETDEWEB)

    Dr. Vahid Sotoudeh; Dr. Richard J. Black; Dr. Behzad Moslehi; Mr. Aleks Plavsic

    2010-10-30

    IFOS in collaboration with Auburn University demonstrated the feasibility of a Fiber Bragg Grating (FBG) integrated sensor system capable of providing real time in-situ defect detection, localization and quantification of damage. In addition, the system is capable of validating wind turbine blade structural models, using recent advances in non-contact, non-destructive dynamic testing of composite structures. This new generation method makes it possible to analyze wind turbine blades not only non-destructively, but also without physically contacting or implanting intrusive electrical elements and transducers into the structure. Phase I successfully demonstrated the feasibility of the technology with the construction of a 1.5 kHz sensor interrogator and preliminary instrumentation and testing of both composite material coupons and a wind turbine blade.

  8. Field measurement of wind pressure and wind-induced vibration of large-span spatial cable-truss system under strong wind or typhoon

    Directory of Open Access Journals (Sweden)

    ZHANG Zhihong

    2013-10-01

    Full Text Available In order to ensure wind-resistance safety of large-span pre-stressed flexible system in southeast coast area of China,and to prepare something for revising of current codes of practice or technical standards,the present paper conducts field measurement of wind pressure and wind-induced vibration of a practical and typical large-span spatial cable-truss system-lunar stadium in Yueqing city.Wind loading and wind effects on full-scale structure under strong wind or typhoon in real architectural environment can be obtained directly and effectively.Field measurement is the best way to investigate the wind loading property,wind effects,and wind-structure interactions of large-span flexible system.Measured data will be highly valuable for scientific research and practical design.On the other hand,it also provides the basis of wind-resistance safety design of this kind of tension structures.If any creative development,it would dramatically improve the research level of large-span pre-stressed flexible system in our country.

  9. Wind energy in Manitoba

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1995-12-31

    Various types of wind energy systems were described. The most popular wind energy system uses a high speed propeller, and has a typical efficiency of 40 per cent. A 3 kW two blade propeller wind energy system was set up as a demonstration project at Fort Whyte Centre in Winnipeg, Manitoba. It generates about four per cent of the electrical requirements of the centre. Other types of wind energy systems include the Darrieus wind energy system using a wind turbine, the Savonius and Multiblade systems, and Hybrid systems. A group of wind energy systems working together is known as a wind farm; such farms have been in operation for many years in high wind areas of the USA. In Manitoba, no wind energy system operates for the sole purpose of generating and selling electricity to a local utility, but some wind energy systems can feed surplus energy into the utility system. A review of environmental impacts, economic considerations and an assessment of wind resources within Manitoba, was also provided. 4 figs.

  10. Wind Turbine Blade Design System - Aerodynamic and Structural Analysis

    Science.gov (United States)

    Dey, Soumitr

    2011-12-01

    The ever increasing need for energy and the depletion of non-renewable energy resources has led to more advancement in the "Green Energy" field, including wind energy. An improvement in performance of a Wind Turbine will enhance its economic viability, which can be achieved by better aerodynamic designs. In the present study, a design system that has been under development for gas turbine turbomachinery has been modified for designing wind turbine blades. This is a very different approach for wind turbine blade design, but will allow it to benefit from the features inherent in the geometry flexibility and broad design space of the presented system. It starts with key overall design parameters and a low-fidelity model that is used to create the initial geometry parameters. The low-fidelity system includes the axisymmetric solver with loss models, T-Axi (Turbomachinery-AXIsymmetric), MISES blade-to-blade solver and 2D wing analysis code XFLR5. The geometry parameters are used to define sections along the span of the blade and connected to the CAD model of the wind turbine blade through CAPRI (Computational Analysis PRogramming Interface), a CAD neutral API that facilitates the use of parametric geometry definition with CAD. Either the sections or the CAD geometry is then available for CFD and Finite Element Analysis. The GE 1.5sle MW wind turbine and NERL NASA Phase VI wind turbine have been used as test cases. Details of the design system application are described, and the resulting wind turbine geometry and conditions are compared to the published results of the GE and NREL wind turbines. A 2D wing analysis code XFLR5, is used for to compare results from 2D analysis to blade-to-blade analysis and the 3D CFD analysis. This kind of comparison concludes that, from hub to 25% of the span blade to blade effects or the cascade effect has to be considered, from 25% to 75%, the blade acts as a 2d wing and from 75% to the tip 3D and tip effects have to be taken into account

  11. Local fatigue behavior in tapered areas of large offshore wind turbine blades

    DEFF Research Database (Denmark)

    Raeis Hosseiny, Seyed Aydin; Jakobsen, Johnny

    2016-01-01

    failure of an entire blade structure. The local strength degradation under an ultimate static loading, subsequent to several years of fatigue, is predicted for an offshore wind turbine blade. Fatigue failure indexes of different damage modes are calculated using a sub-modeling approach. Multi axial...... stresses are accounted for using a developed failure criterion with residual strengths instead of the virgin strengths. Damage initiation is predicted by including available Wohler curve data of E-Glass fabrics and epoxy matrix into multi-axial fatigue failure criteria. As a result of this study, proper...... knock-down factors for ply-drop effects in wind turbine blades under multi-axial static and fatigue loadings can be obtained....

  12. Local entropy of a nonequilibrium fermion system

    Science.gov (United States)

    Stafford, Charles A.; Shastry, Abhay

    2017-03-01

    The local entropy of a nonequilibrium system of independent fermions is investigated and analyzed in the context of the laws of thermodynamics. It is shown that the local temperature and chemical potential can only be expressed in terms of derivatives of the local entropy for linear deviations from local equilibrium. The first law of thermodynamics is shown to lead to an inequality, not equality, for the change in the local entropy as the nonequilibrium state of the system is changed. The maximum entropy principle (second law of thermodynamics) is proven: a nonequilibrium distribution has a local entropy less than or equal to a local equilibrium distribution satisfying the same constraints. It is shown that the local entropy of the system tends to zero when the local temperature tends to zero, consistent with the third law of thermodynamics.

  13. Dynamics of the east India coastal current. 1. Analytic solutions forced by interior Ekman pumping and local alongshore winds

    Digital Repository Service at National Institute of Oceanography (India)

    Shankar, D.; McCreary, J.P.; Han, W.; Shetye, S.R.

    OF GEOPHYSICAL RESEARCH, VOL. 101, NO. C6, PAGES 13,975-13,991, JUNE 15, 1996 Dynamics of the East India Coastal Current 1. Analytic solutions forced by interior Ekman pumping and local alongshore winds D. Snankar Centre for Mathematical Modelling... linear, continuously stratified model is used to investigate how forcing by interior Ekman pumping and local alongshore winds affects the East India Coastal Current (EICC). Solutions are found analytically to an approximate version of the equations...

  14. Developing an Indicator System for Measuring the Social Sustainability of Offshore Wind Power Farms

    Directory of Open Access Journals (Sweden)

    Tzay-An Shiau

    2016-05-01

    Full Text Available Taiwan’s government has promoted investment in an offshore wind power farm, and local fishermen have protested. A social impact assessment (SIA has examined the impact of the proposed offshore wind power farm on all stakeholders. The main objective of the present study was to develop an indicator system for measuring the social sustainability of offshore wind power farms; this study also reports on the particular case of Taiwan’s offshore wind power project. This study began by defining 35 social sustainability indicators and selecting 23 representative indicators by using rough set theory. Subsequently, 14 key indicators were constructed using the social construction of technology (SCOT method. Finally, we developed a social impact index for evaluating the social sustainability of offshore wind power farms by using the analytic network process and Dempster-Shafer theory. Our social impact index yields a total score of 0.149 for Taiwan’s pilot offshore wind power project; this result indicates that the pilot project is socially sustainable. A substantial contradiction exists between the fishermen’s protest and the results of the social impact assessment. The findings can assist the government in building a coordination platform for the investors and the fishermen. Government regulation is necessary to set boundaries for fishing areas that protect both the fishermen’s and investors’ rights.

  15. Effect of land uses and wind direction on the contribution of local sources to airborne pollen.

    Science.gov (United States)

    Rojo, Jesús; Rapp, Ana; Lara, Beatriz; Fernández-González, Federico; Pérez-Badia, Rosa

    2015-12-15

    The interpretation of airborne pollen levels in cities based on the contribution of the surrounding flora and vegetation is a useful tool to estimate airborne allergen concentrations and, consequently, to determine the allergy risk for local residents. This study examined the pollen spectrum in a city in central Spain (Guadalajara) and analysed the vegetation landscape and land uses within a radius of 20km in an attempt to identify and locate the origin of airborne pollen and to determine the effect of meteorological variables on pollen emission and dispersal. The results showed that local wind direction was largely responsible for changes in the concentrations of different airborne pollen types. The land uses contributing most to airborne pollen counts were urban green spaces, though only 0.1% of the total surface area studied, and broadleaved forest which covered 5% of the study area. These two types of land use together accounted for 70% of the airborne pollen. Crops, scrubland and pastureland, though covering 80% of the total surface area, contributed only 18.6% to the total pollen count, and this contribution mainly consisted of pollen from Olea and herbaceous plants, including Poaceae, Urticaceae and Chenopodiaceae-Amaranthaceae. Pollen from ornamental species were mainly associated with easterly (Platanus), southerly (Cupressaceae) and westerly (Cupressaceae and Platanus) winds from the areas where the city's largest parks and gardens are located. Quercus pollen was mostly transported by winds blowing in from holm-oak stands on the eastern edge of the city. The highest Populus pollen counts were associated with easterly and westerly winds blowing in from areas containing rivers and streams. The airborne pollen counts generally rose with increasing temperature, solar radiation and hours of sunlight, all of which favour pollen release. In contrast, pollen counts declined with increased relative humidity and rainfall, which hinder airborne pollen transport.

  16. How to Establish Local Renewable Energy Scenarios in the Context of National Energy Systems

    DEFF Research Database (Denmark)

    Thellufsen, Jakob Zinck

    2014-01-01

    In the transition to 100% renewable energy systems, the local and regional implementation of renewable energy becomes essential. To implement energy systems that fulfill national targets, local investments have to be made creating a need for local energy planning. However, challenges emerge when...... local energy plans must be related to each other and to national targets. For instance, in terms of the division of resources between the countryside and cities, the amount of biomass to be used, and the placement of wind turbines. If local plans do not include the context of surrounding energy systems...... and only optimise locally, the consequences might be national sub-optimisation, including excessive biomass use, wind turbines in non-favourable positions, and the misalignment of resources between the open land and the cities. Thus, there is a risk that these necessary local plans can lead...

  17. Mitigation of Power System Oscillation Caused by Wind Power Fluctuation

    DEFF Research Database (Denmark)

    Su, Chi; Hu, Weihao; Chen, Zhe

    2013-01-01

    oscillation mitigation controllers are proposed and compared. A model of direct-drive-full-convertor-based wind farm connected to the IEEE 10-machine 39-bus system is adopted as the test system. The calculations and simulations are conducted in DIgSILENT PowerFactory 14.0. Results are presented to show...

  18. Wind Solar Hybrid System Rectifier Stage Topology Simulation

    Directory of Open Access Journals (Sweden)

    Anup M. Gakare

    2014-06-01

    Full Text Available This paper presents power-control strategies of a grid-connected hybrid generation system with versatile power transfer. The hybrid system allows maximum utilization of freely available renewable sources like wind and photovoltaic energies. This paper presents a new system configuration of the multi input rectifier stage for a hybrid wind and photovoltaic energy system. This configuration allows the two sources to supply the load simultaneously depending on the availability of the energy sources maximum power from the sun when it is available. An adaptive MPPT algorithm with a standard perturbs and observed method will be used for the Photo Voltaic system. The main advantage of the hybrid system is to give continuous power supply to the load. The gating pulses to the inverter switches are implemented with conventional and fuzzy controller. This hybrid wind-photo voltaic system is modeled in MATLAB/ SIMULINK environment. Simulation circuit is analyzed and results are presented for this hybrid wind and solar energy system.

  19. Improvement of Wind Energy Production through HVDC Systems

    Directory of Open Access Journals (Sweden)

    Morris Brenna

    2017-01-01

    Full Text Available Variable and non-programmable resources, such as solar and wind, have undergone a stunning growth in recent years and are likely to gain even more importance in the future. Their strong presence in the national electricity mix has created issues in many countries regarding the secure operation of the power system. In order to guarantee the stability of the system, several TSOs have resorted to wind energy curtailment, which represents a waste of clean energy and an economic loss. In order to analyze this issue, a model of the Italian power system was developed, a program able to simulate the electricity dispatching mechanism. The model was, then, used to evaluate possible solutions to reduce wind curtailment. In particular, a proposal for the construction of an HVDC line linking Southern and Northern Italy was studied.

  20. Reliability-oriented energy storage sizing in wind power systems

    DEFF Research Database (Denmark)

    Qin, Zian; Liserre, Marco; Blaabjerg, Frede;

    2014-01-01

    Energy storage can be used to suppress the power fluctuations in wind power systems, and thereby reduce the thermal excursion and improve the reliability. Since the cost of the energy storage in large power application is high, it is crucial to have a better understanding of the relationship...... between the size of the energy storage and the reliability benefit it can generate. Therefore, a reliability-oriented energy storage sizing approach is proposed for the wind power systems, where the power, energy, cost and the control strategy of the energy storage are all taken into account....... With the proposed approach, the computational effort is reduced and the impact of the energy storage system on the reliability of the wind power converter can be quantified....

  1. Lightning protection of flap system for wind turbine blades

    DEFF Research Database (Denmark)

    Candela Garolera, Anna; Madsen, Søren Find

    The aim of this PhD project was to investigate the behaviour of a Controllable Rubber Trailing Edge Flap (CRTEF) in a wind turbine blade when it is exposed to lightning discharges, and find the best technical solution to protect the CRTEF and the controlling system against lightning, based...... on the results of simulation models and high voltage tests. Wind turbines are a common target of lightning due to their height and location, and blades are the components most exposed to direct discharges. Protecting the blades against lightning is specially challenging, mainly because of the combination...... of a broader, EUDP funded project, whose overall objective was to develop a prototype active trailing edge flap system for a wind turbine blade which constitutes a complete, reliable and robust load control flap system for a full scale turbine, ready for prototype testing....

  2. Study of LANs access technologies in wind power system

    DEFF Research Database (Denmark)

    Wei, Mu; Chen, Zhe

    2010-01-01

    Due to the energy challenges in the world, new types of generation technologies, such as renewable energy based generators, attract great attention and are being quickly developed, which results in the dramatic developments and changes in modern power systems, the communication technologies play...... a increasingly important role in guaranteeing the power system’s stability, reliability, and security. In this paper the necessity of communication technologies employed in wind power system are introduced. According the International Standards Organization (ISO) reference 7-layered model, the communication...... power environment are explained and discussed. Furthermore the simulation of application of Ethernet in an offshore wind farm communication network by a software, OPNET, is elaborated. With the investigation of the communication technologies in this paper, the offshore wind farm SCADA system can...

  3. 622 Mbps High-speed satellite communication system for WINDS

    Science.gov (United States)

    Ogawa, Yasuo; Hashimoto, Yukio; Yoshimura, Naoko; Suzuki, Ryutaro; Gedney, Richard T.; Dollard, Mike

    2006-07-01

    WINDS is the experimental communications satellite currently under joint development by Japanese Aerospace Exploration Agency (JAXA) and the National Institute of Information and Communications Technology (NICT). The high-speed satellite communication system is very effective for quick deployment of high-speed networks economically. The WINDS will realize ultra high-speed networking and demonstrate operability of satellite communication systems in high-speed internet. NICT is now developing high-speed satellite communication system for WINDS. High-speed TDMA burst modem with high performance TPC error correction is underdevelopment. Up to the DAC on the transmitter and from the ADC on the receiver, all modem functions are performed in the digital processing technology. Burst modem has been designed for a user data rate up to 1244 Mbps. NICT is developing the digital terminal as a user interface and a network controller for this earth station. High compatibility with the Internet will be provided.

  4. Proceedings of the fourth biennial conference and workshop on wind energy conversion systems

    Energy Technology Data Exchange (ETDEWEB)

    Kottler, Jr., R. J. [ed.

    1980-06-01

    Separate abstracts are included for papers presented concerning research and development requirements and utility interface and institutional issues for small-scale systems; design requirements and research and development requirements for large-scale systems; economic and operational requirements of large-scale wind systems; wind characteristics and wind energy siting; international activities; wind energy applications in agriculture; federal commercialization and decentralization plans; and wind energy innovative systems.

  5. Wind Power - WINDSPD100_IN: Mean Wind Speed at Height of 100 Meters above Ground, Derived from Mesoscale Atmospheric Simulation System and WindMap (TrueWind Solutions, 200-Meter Grid)

    Data.gov (United States)

    NSGIC GIS Inventory (aka Ramona) — The following is excerpted from an unpublished report by Michael Brower (2004): "Using the MesoMap system, TrueWind has produced maps of mean wind speed in Indiana...

  6. Wind Power - WINDPWR100_IN: Mean Wind Power at Height of 100 Meters above Ground, Derived from Mesoscale Atmospheric Simulation System and WindMap(TrueWind Solutions, 200-Meter Grid)

    Data.gov (United States)

    NSGIC GIS Inventory (aka Ramona) — The following is excerpted from an unpublished report by Michael Brower (2004): "Using the MesoMap system, TrueWind has produced maps of mean wind speed in Indiana...

  7. Wind Power - WINDSPD50_IN: Mean Wind Speed at Height of 50 Meters above Ground, Derived from Mesoscale Atmospheric Simulation System and WindMap (TrueWind Solutions, 200-Meter Grid)

    Data.gov (United States)

    NSGIC GIS Inventory (aka Ramona) — The following is excerpted from an unpublished report by Michael Brower (2004): "Using the MesoMap system, TrueWind has produced maps of mean wind speed in Indiana...

  8. Wind Power - WINDPWR50_IN: Mean Wind Power at Height of 50 Meters above Ground, Derived from Mesoscale Atmospheric Simulation System and WindMap (TrueWind Solutions, 200-Meter Grid)

    Data.gov (United States)

    NSGIC GIS Inventory (aka Ramona) — The following is excerpted from an unpublished report by Michael Brower (2004): "Using the MesoMap system, TrueWind has produced maps of mean wind speed in Indiana...

  9. Wind Generation Participation in Power System Frequency Response: Preprint

    Energy Technology Data Exchange (ETDEWEB)

    Gevorgian, Vahan; Zhang, Yingchen

    2017-01-01

    The electrical frequency of an interconnected power system must be maintained close its nominal level at all times. Excessive under- and overfrequency excursions can lead to load shedding, instability, machine damage, and even blackouts. There is a rising concern in the electric power industry in recent years about the declining amount of inertia and primary frequency response (PFR) in many interconnections. This decline may continue due to increasing penetrations of inverter-coupled generation and the planned retirements of conventional thermal plants. Inverter-coupled variable wind generation is capable of contributing to PFR and inertia with a response that is different from that of conventional generation. It is not yet entirely understood how such a response will affect the system at different wind power penetration levels. The modeling work presented in this paper evaluates the impact of wind generation's provision of these active power control strategies on a large, synchronous interconnection. All simulations were conducted on the U.S. Western Interconnection with different levels of instantaneous wind power penetrations (up to 80%). The ability of wind power plants to provide PFR - and a combination of synthetic inertial response and PFR - significantly improved the frequency response performance of the system.

  10. Keys to success for wind power in isolated power systems

    Energy Technology Data Exchange (ETDEWEB)

    Hansen, J.C.; Lundsager, P.; Bindner, H.; Hansen, L.; Frandsen, S. [Risoe National Lab., Wind Energy and Atmospheric Physics Dept., Roskilde (Denmark)

    1999-03-01

    It is generally expected that wind power could contribute significantly to the electricity supply in power systems of small and medium sized isolated communities. The market for such applications of wind power has not yet materialized. Wind power in isolated power systems have the main market potentials in developing countries. The money available world-wide for this technological development is limited and the necessary R and D and pilot programmes have difficult conditions. Consequently, technology developed exclusively for developing countries rarely becomes attractive for consumers, investors and funding agencies. A Danish research project is aimed at studying development of methods and guidelines rather than `universal solutions` for the use of wind energy in isolated communities. This paper report on the findings of the project regarding barriers removal and engineering methods development, with a focus on analysis and specification of user demand and priorities, numerical modeling requirements as well as wind power impact on power quality and power system operation. Input will be provided on these subjects for establishing of common guidelines on relevant technical issues, and thereby enabling the making of trustworthy project preparation studies. (au) EFP-97. 12 refs.

  11. A Review of Hybrid Solar PV and Wind Energy System

    Directory of Open Access Journals (Sweden)

    Rashid Al Badwawi

    2015-07-01

    Full Text Available Due to the fact that solar and wind power is intermittent and unpredictable in nature, higher penetration of their types in existing power system could cause and create high technical challenges especially to weak grids or stand-alone systems without proper and enough storage capacity. By integrating the two renewable resources into an optimum combination, the impact of the variable nature of solar and wind resources can be partially resolved and the overall system becomes more reliable and economical to run. This paper provides a review of challenges and opportunities / solutions of hybrid solar PV and wind energy integration systems. Voltage and frequency fluctuation, and harmonics are major power quality issues for both grid-connected and stand-alone systems with bigger impact in case of weak grid. This can be resolved to a large extent by having proper design, advanced fast response control facilities, and good optimization of the hybrid systems. The paper gives a review of the main research work reported in the literature with regard to optimal sizing design, power electronics topologies and control. The paper presents a review of the state of the art of both grid-connected and stand-alone hybrid solar and wind systems.

  12. Grid-connected inverter for wind power generation system

    Institute of Scientific and Technical Information of China (English)

    YANG Yong; RUAN Yi; SHEN Huan-qing; TANG Yan-yan; YANG Ying

    2009-01-01

    In wind power generation system the grid-connected inverter is an important section for energy conversion and transmission, of which the performance has a direct influence on the entire wind power generation system. The mathematical model of the grid-connected inverter is deduced firstly. Then, the space vector pulse width modulation (SVPWM) is analyzed. The power factor can be controlled close to unity, leading or lagging, which is realized based on PI-type current controller and grid voltage vector-oriented control. The control strategy is verified by the simulation and experimental results with a good sinusoidal current, a small harmonic component and a fast dynamic response.

  13. Grid converters for photovoltaic and wind power systems

    CERN Document Server

    Teodorescu, Remus; Rodríguez, Pedro

    2011-01-01

    "Grid Converters for Photovoltaic and Wind Power Systems provides a comprehensive description of the control of grid converters for photovoltaic and wind power systems. The authors present a range of control methods for meeting the latest application, power quality and power conversion requirements and standards, as well as looking towards potential future control functions. Practical examples, exercises, and an accompanying website with simulation models using Matlab and Simulink environments, and PSIM software make this text a pragmatic resource for electrical engineers as well as students taking related courses"--

  14. An Optimal Parameterization Framework for Infrasonic Tomography of the Stratospheric Winds Using Non-Local Sources

    Science.gov (United States)

    Blom, Philip S.; Marcillo, Omar

    2016-12-01

    A method is developed to apply acoustic tomography methods to a localized network of infrasound arrays with intention of monitoring the atmosphere state in the region around the network using non-local sources without requiring knowledge of the precise source location or non-local atmosphere state. Closely spaced arrays provide a means to estimate phase velocities of signals that can provide limiting bounds on certain characteristics of the atmosphere. Larger spacing between such clusters provide a means to estimate celerity from propagation times along multiple unique stratospherically or thermospherically ducted propagation paths and compute more precise estimates of the atmosphere state. In order to avoid the commonly encountered complex, multi-modal distributions for parametric atmosphere descriptions and to maximize the computational efficiency of the method, an optimal parameterization framework is constructed. This framework identifies the ideal combination of parameters for tomography studies in specific regions of the atmosphere and statistical model selection analysis shows that high quality corrections to the middle atmosphere winds can be obtained using as few as three parameters. Comparison of the resulting estimates for synthetic datasets shows qualitative agreement between the middle atmosphere winds and those estimated from infrasonic travel time observations.

  15. An optimal parametrization framework for infrasonic tomography of the stratospheric winds using non-local sources

    Science.gov (United States)

    Blom, Philip S.; Marcillo, Omar E.

    2017-03-01

    A method is developed to apply acoustic tomography methods to a localized network of infrasound arrays with intention of monitoring the atmosphere state in the region around the network using non-local sources without requiring knowledge of the precise source location or non-local atmosphere state. Closely spaced arrays provide a means to estimate phase velocities of signals that can provide limiting bounds on certain characteristics of the atmosphere. Larger spacing between such clusters provide a means to estimate celerity from propagation times along multiple unique stratospherically or thermospherically ducted propagation paths and compute more precise estimates of the atmosphere state. In order to avoid the commonly encountered complex, multimodal distributions for parametric atmosphere descriptions and to maximize the computational efficiency of the method, an optimal parametrization framework is constructed. This framework identifies the ideal combination of parameters for tomography studies in specific regions of the atmosphere and statistical model selection analysis shows that high quality corrections to the middle atmosphere winds can be obtained using as few as three parameters. Comparison of the resulting estimates for synthetic data sets shows qualitative agreement between the middle atmosphere winds and those estimated from infrasonic traveltime observations.

  16. A Reexamination of the Emergy Input to a System from the Wind.

    Science.gov (United States)

    The wind energy absorbed in the global boundary layer (GBL, 900 mb surface) is the basis for calculating the wind emergy input for any system on the Earth’s surface. Estimates of the wind emergy input to a system depend on the amount of wind energy dissipated, which can hav...

  17. Distributed generation system using wind/photovoltaic/fuel cell

    Science.gov (United States)

    Buasri, Panhathai

    This dissertation investigates the performance and the operation of a distributed generation (DG) power system using wind/photovoltaic/fuel cell (W/PV/FC). The power system consists of a 2500 W photovoltaic array subsystem, a 500 W proton exchange membrane fuel cell (PEMFC) stack subsystem, 300 W wind turbine, 500 W wind turbine, and 1500 W wind energy conversion subsystems. To extract maximum power from the PV, a maximum power point tracker was designed and fabricated. A 4 kW single phase inverter was used to convert the DC voltage to AC voltage; also a 44 kWh battery bank was used to store energy and prevent fluctuation of the power output of the DG system. To connect the fuel cell to the batteries, a DC/DC controller was designed and fabricated. To monitor and study the performance of the DG system under variable conditions, a data acquisition system was designed and installed. The fuel cell subsystem performance was evaluated under standalone operation using a variable resistance and under interactive mode, connected to the batteries. The manufacturing data and the experimental data were used to develop an electrical circuit model to the fuel cell. Furthermore, harmonic analysis of the DG system was investigated. For an inverter, the AC voltage delivered to the grid changed depending on the time, load, and electronic equipment that was connected. The quality of the DG system was evaluated by investigating the harmonics generated by the power electronics converters. Finally, each individual subsystem of the DG system was modeled using the neuro-fuzzy approach. The model was used to predict the performance of the DG system under variable conditions, such as passing clouds and wind gust conditions. The steady-state behaviors of the model were validated by the experimental results under different operating conditions.

  18. Future on Power Electronics for Wind Turbine Systems

    DEFF Research Database (Denmark)

    Blaabjerg, Frede; Ma, Ke

    2013-01-01

    generators, power electronic systems, and control solutions have to be introduced to improve the characteristics of the wind power plant and make it more suitable to be integrated into the power grid. Meanwhile, there are also some emerging technology challenges, which need to be further clarified...... and investigated. This paper gives an overview and discusses some development trends in the technologies used for wind power systems. First, the developments of technology and market are generally discussed. Next, several state-of-the-art wind turbine concepts, as well as the corresponding power electronic...... converters and control structures, are reviewed, respectively. Furthermore, grid requirements and the technology challenges for the future WTS are also addressed....

  19. Effect of operating methods of wind turbine generator system on net power extraction under wind velocity fluctuations in fields

    Energy Technology Data Exchange (ETDEWEB)

    Wakui, Tetsuya; Yamaguchi, Kazuya; Hashizume, Takumi [Waseda Univ., Advanced Research Inst. for Science and Engineering, Tokyo (Japan); Outa, Eisuke [Waseda Univ., Mechanical Engineering Dept., Tokyo (Japan); Tanzawa, Yoshiaki [Nippon Inst. of Technology, Mechanical Engineering Dept., Saitama (Japan)

    1999-01-01

    The effect of how a wind turbine generator system is operated is discussed from the viewpoint of net power extraction with wind velocity fluctuation in relation to the scale and the dynamic behaviour of the system. On a wind turbine generator system consisting of a Darrieus-Savonius hybrid wind turbine, a load generator and a battery, we took up two operating methods: constant tip speed ratio operation for a stand-alone system (Scheme 1) and synchronous operation by connecting a grid (Scheme 2). With our simulation model, using the result of the net extracting power, we clarified that Scheme 1 is more effective than Scheme 2 for small-scale systems. Furthermore, in Scheme 1, the appropriate rated power output of the system under each wind condition can be confirmed. (Author)

  20. Stability and control of wind farms in power systems

    Energy Technology Data Exchange (ETDEWEB)

    Jauch, C.

    2006-10-15

    The Ph.D. project 'Stability and Control of Wind Farms in Power Systems' deals with some selected problems related to wind power in power systems. With increasing wind power penetration, wind turbines substitute the power production of conventional power plants. Therefore, wind turbines also have to take over the power system stabilisation and control tasks, that were traditionally carried out by conventional power plants. Out of the many aspects related to this problem, this project focuses on transient fault ride-through and power system stabilisation. The selection of turbine types considered in this project is limited to active-stall turbines and variable speed, variable pitch turbines with gearboxes and full-scale converter-connected synchronous generators. As a basis for the project, a study into the state of the art is conducted at the beginning of the project. Grid connection requirements that were in force, or published as drafts, at the time, and scientific literature related to the topic, are studied. The project is based on simulations of wind turbines in a power system simulations tool. Some of the models used in this project were readily available prior to the project; the development of others is part of the project. The most extensive modelling work deals with the design of the electrical part of the variable speed turbine and its controls. To simulate realistic grid operation the wind turbine models are connected to an aggregated model of the Nordic power system. For that purpose the Nordic power system model, which was available prior to the project, is extended with a realistic feeder configuration. It is commonly demanded from modern wind turbines, that they must not disconnect in case of transient faults. Therefore, controllers are designed that enable the two turbine types to ride through transient faults. With these transient fault controllers the wind turbines can stay connected to the grid, such that their generation capacity is

  1. Development of a cooling system for superconducting wind turbine generator

    Science.gov (United States)

    Furuse, Mitsuho; Fuchino, Shuichiro; Okano, Makoto; Natori, Naotake; Yamasaki, Hirofumi

    2016-12-01

    This paper deals with the cooling system for high-Tc superconducting (HTS) generators for large capacity wind turbines. We have proposed a cooling system with a heat exchanger and circulation pumps to cool HTS field windings designed for 10 MW-class superconducting generators. In the cooling system, the refrigerants in the stationary and rotational systems are completely separated; heat between the two systems exchanges using a rotational-stationary heat exchanger. The refrigerant in rotational system is circulated by highly reliable pumps. We designed the rotational-stationary heat exchanger based on a conventional shell-and tube type heat exchanger. We also demonstrated that heat exchange in cryogenic temperature is possible with a commercially available heat exchanger. We devised a novel and highly reliable cryogenic helium circulation pump with magnetic reciprocating rotation system and verified its underlying principle with a small-scale model.

  2. Communications for Coordinative Control of Wind Power Systems

    DEFF Research Database (Denmark)

    Wei, Mu

    . The performances of FSWT and DFIG connected DGS are compared and analysed. At last, the cyber security study is presented, due to the important place of security in power system communications. A security domain model is proposed to guide the implementation of the security technologies. Cyber security related...... system control strategies for wind power integration, in order to achieve coordinative control for a secure and efficient power system. The project basically contains three main aspects: studies on DGS (Distributed Generation System) characteristics, analysis of communication technologies...... simulation results reveal the important impact of the security configuration on improving the performance of the associated electric power system data communication systems. This PhD study explores a new aspect of the investigations of wind power system components characteristics, from communication...

  3. Evaluation of different operational strategies for lithium ion battery systems connected to a wind turbine for primary frequency regulation and wind power forecast accuracy improvement

    DEFF Research Database (Denmark)

    Swierczynski, Maciej Jozef; Stroe, Daniel Ioan; Stan, Ana-Irina

    2012-01-01

    High penetration levels of variable wind energy sources can cause problems with their grid integration. Energy storage systems connected to wind turbine/wind power plants can improve predictability of the wind power production and provide ancillary services to the grid. This paper investigates ec...... economics of different operational strategies for Li-ion systems connected to wind turbines for wind power forecast accuracy improvement and primary frequency regulation....

  4. Source reliability in a combined wind-solar-hydro system

    Science.gov (United States)

    Traca de Almeida, A.; Martins, A.; Jesus, H.; Climaco, J.

    1983-06-01

    The results of an examination of the feasibility of using coupled wind-solar-hydro power generation systems to provide all of Portugal's electricity by the year 2000 are reported. Portugal used 15.6 TWh of electricity in 1981, of which hydro supplied 10 TWh. Demand is expected to reach 34 TWh in 2000 AD. The full development of hydropower resource would furnish 18 TWh and a storage capacity of 4.5 TWh. The installed hydro system could meet the peak demand of 6 GW, while solar cells and wind turbines must produce 16 TWh annually plus a reserve. The Growian wind turbine, 100 m tall, is considered for its 2.2 MW output. A coastal strip of wind turbines 150 x 20 km, with 1 km spacing between the machines, would be needed to produce 5.4 GW of power. Partially tracking solar cell arrays generating 9.4 GW of electricity would require an area of 100 sq km. Computer simulations of the annual rainfall, combined with projections of the variations in wind-solar output, demonstrates that a reserve margin of 1.20 will be necessary. The costs of installation of the renewable energy converters are estimated at about three times that currently necessary for obtaining the same capacity from fission power plants, although the situation may change due to import and technical considerations.

  5. Locally linear neurofuzzy modeling and prediction of geomagnetic disturbances based on solar wind conditions

    Science.gov (United States)

    Sharifie, Javad; Lucas, Caro; Araabi, Babak N.

    2006-06-01

    Disturbance storm time index (Dst) is nonlinearly related to solar wind data. In this paper, Dst past values, Dst derivative, past values of southward interplanetary magnetic field, and the square root of dynamic pressure are used as inputs for modeling and prediction of the Dst index, especially during extreme events. The geoeffective solar wind parameters are selected depending on the physical background of the geomagnetic storm procedure and physical models. A locally linear neurofuzzy model with a progressive tree construction learning algorithm is applied as a powerful tool for nonlinear modeling of Dst index on the basis of its past values and solar wind parameters. The result for modeling and prediction of several intense storms shows that the geomagnetic disturbance Dst index based on geoeffective parameters is a nonlinear model that could be considered as the nonlinear extension of empirical linear physical models. The method is applied for prediction of some geomagnetic storms. Obtained results show that using the proposed method, the predicted values of several extreme storms are highly correlated with observed values. In addition, prediction of the main phase of many storms shows a good match with observed data, which constitutes an appropriate approach for solar storm alerting to vulnerable industries.

  6. Evaluation protocol for the WIND system atmospheric models

    Energy Technology Data Exchange (ETDEWEB)

    Fast, J.D.

    1991-12-31

    Atmospheric transport and diffusion models have been developed for real-time calculations of the location and concentration of toxic or radioactive materials during a accidental release at the Savannah River Site (SRS). These models are have been incorporated into an automated menu-driven computer based system called the WIND (Weather INformation and Display) system. In an effort to establish more formal quality assurance procedures for the WIND system atmospheric codes, a software evaluation protocol is being developed. An evaluation protocol is necessary to determine how well they may perform in emergency response (real-time) situations. The evaluation of high-impact software must be conducted in accordance with WSRC QA Manual, 1Q, QAP 20-1. This report will describe the method that will be used to evaluate the atmospheric models. The evaluation will determine the effectiveness of the atmospheric models in emergency response situations, which is not necessarily the same procedure used for research purposes. The format of the evaluation plan will provide guidance for the evaluation of atmospheric models that may be added to the WIND system in the future. The evaluation plan is designed to provide the user with information about the WIND system atmospheric models that is necessary for emergency response situations.

  7. Evaluation protocol for the WIND system atmospheric models

    Energy Technology Data Exchange (ETDEWEB)

    Fast, J.D.

    1991-01-01

    Atmospheric transport and diffusion models have been developed for real-time calculations of the location and concentration of toxic or radioactive materials during a accidental release at the Savannah River Site (SRS). These models are have been incorporated into an automated menu-driven computer based system called the WIND (Weather INformation and Display) system. In an effort to establish more formal quality assurance procedures for the WIND system atmospheric codes, a software evaluation protocol is being developed. An evaluation protocol is necessary to determine how well they may perform in emergency response (real-time) situations. The evaluation of high-impact software must be conducted in accordance with WSRC QA Manual, 1Q, QAP 20-1. This report will describe the method that will be used to evaluate the atmospheric models. The evaluation will determine the effectiveness of the atmospheric models in emergency response situations, which is not necessarily the same procedure used for research purposes. The format of the evaluation plan will provide guidance for the evaluation of atmospheric models that may be added to the WIND system in the future. The evaluation plan is designed to provide the user with information about the WIND system atmospheric models that is necessary for emergency response situations.

  8. Effect of land uses and wind direction on the contribution of local sources to airborne pollen

    Energy Technology Data Exchange (ETDEWEB)

    Rojo, Jesús; Rapp, Ana; Lara, Beatriz; Fernández-González, Federico; Pérez-Badia, Rosa

    2015-12-15

    The interpretation of airborne pollen levels in cities based on the contribution of the surrounding flora and vegetation is a useful tool to estimate airborne allergen concentrations and, consequently, to determine the allergy risk for local residents. This study examined the pollen spectrum in a city in central Spain (Guadalajara) and analysed the vegetation landscape and land uses within a radius of 20 km in an attempt to identify and locate the origin of airborne pollen and to determine the effect of meteorological variables on pollen emission and dispersal. The results showed that local wind direction was largely responsible for changes in the concentrations of different airborne pollen types. The land uses contributing most to airborne pollen counts were urban green spaces, though only 0.1% of the total surface area studied, and broadleaved forest which covered 5% of the study area. These two types of land use together accounted for 70% of the airborne pollen. Crops, scrubland and pastureland, though covering 80% of the total surface area, contributed only 18.6% to the total pollen count, and this contribution mainly consisted of pollen from Olea and herbaceous plants, including Poaceae, Urticaceae and Chenopodiaceae–Amaranthaceae. Pollen from ornamental species were mainly associated with easterly (Platanus), southerly (Cupressaceae) and westerly (Cupressaceae and Platanus) winds from the areas where the city's largest parks and gardens are located. Quercus pollen was mostly transported by winds blowing in from holm-oak stands on the eastern edge of the city. The highest Populus pollen counts were associated with easterly and westerly winds blowing in from areas containing rivers and streams. The airborne pollen counts generally rose with increasing temperature, solar radiation and hours of sunlight, all of which favour pollen release. In contrast, pollen counts declined with increased relative humidity and rainfall, which hinder airborne pollen

  9. Variable-Speed Wind System Design : Final Report.

    Energy Technology Data Exchange (ETDEWEB)

    Lauw, Hinan K.; Weigand, Claus H.; Marckx, Dallas A.; Electronic Power Conditioning, Inc.

    1993-10-01

    Almost from the onset of the development of wind energy conversion systems (WECS), it was known that variable-speed operation of the turbine would maximize energy capture. This study was commissioned to assess the cost, efficiency gain, reduction of the cost of energy (COE), and other operating implications of converting the existing hardware of a modern fixed-speed wind energy conversion system to variable-speed operation. The purpose of this study was to develop a preliminary design for the hardware required to allow variable-speed operation using a doubly-fed generator with an existing fixed-speed wind turbine design. The turbine selected for this study is the AWT-26 designed and built by Advanced Wind Turbines Inc. of Redmond, Washington. The lowest projected COE using this variable-speed generation system is projected to be $0.0499/kWh, compared to the lowest possible COE with fixed-speed generation which is projected to be $0.0546/kWh. This translates into a 8.6% reduction of the COE using this variable-speed generation option. The preliminary system design has advanced to where the printed circuit boards can be physically laid out based on the schematics and the system software can be written based on the control flow-charts. The core of hardware and software has been proven to be successful in earlier versions of VSG systems. The body of this report presents the results of the VSWG system development. Operation under normal and fault conditions is described in detail, the system performance for variable-speed operation is estimated and compared to the original fixed-speed system performance, and specifications for all system components (generator, power electronic converter, and system controller) are given. Costs for all components are estimated, and incremental system cost is compared to incremental energy production. Finally, operational features of the VSWG which are not available in the existing FSWG system are outlined.

  10. Isolated systems with wind power. An implementation guideline

    Energy Technology Data Exchange (ETDEWEB)

    Clausen, N.E.; Bindner, H.; Frandsen, S.; Hansen, J.C.; Hansen, L.H.; Lundsager, P.

    2001-06-01

    The overall objective of this research project is to study the development of methods and guidelines rather than 'universal solutions' for the use of wind energy in isolated communities. So far most studies of isolated systems with wind power have been case-oriented and it has proven difficult to extend results from one project to another, not least due to the strong individuality that has characterised such systems in design and implementation. In the present report a unified and generally applicable approach is attempted in order to support a fair assessment of the technical and economical feasibility of isolated power supply systems with wind energy. General guidelines and checklists on which facts and data are needed to carry out a project feasibility analysis are presented as well as guidelines how to carry out the project feasibility study and the environmental analysis. The report outlines the results of the project as a set of proposed guidelines to be applied when developing a project containing an application of wind in an isolated power system. It is the author's hope that this will facilitate the development of projects and enhance electrification of small rural communities in developing countries. (au)

  11. Design of multi-energy Helds coupling testing system of vertical axis wind power system

    Science.gov (United States)

    Chen, Q.; Yang, Z. X.; Li, G. S.; Song, L.; Ma, C.

    2016-08-01

    The conversion efficiency of wind energy is the focus of researches and concerns as one of the renewable energy. The present methods of enhancing the conversion efficiency are mostly improving the wind rotor structure, optimizing the generator parameters and energy storage controller and so on. Because the conversion process involves in energy conversion of multi-energy fields such as wind energy, mechanical energy and electrical energy, the coupling effect between them will influence the overall conversion efficiency. In this paper, using system integration analysis technology, a testing system based on multi-energy field coupling (MEFC) of vertical axis wind power system is proposed. When the maximum efficiency of wind rotor is satisfied, it can match to the generator function parameters according to the output performance of wind rotor. The voltage controller can transform the unstable electric power to the battery on the basis of optimizing the parameters such as charging times, charging voltage. Through the communication connection and regulation of the upper computer system (UCS), it can make the coupling parameters configure to an optimal state, and it improves the overall conversion efficiency. This method can test the whole wind turbine (WT) performance systematically and evaluate the design parameters effectively. It not only provides a testing method for system structure design and parameter optimization of wind rotor, generator and voltage controller, but also provides a new testing method for the whole performance optimization of vertical axis wind energy conversion system (WECS).

  12. Modeling and analysis of DFIG in wind energy conversion system

    Directory of Open Access Journals (Sweden)

    Omer Elfaki Elbashir, Wang Zezhong, Liu Qihui

    2014-01-01

    Full Text Available This paper deals with the modeling, analysis, and simulation of a doubly-fed induction generator (DFIG driven by a wind turbine. The grid connected wind energy conversion system (WECS is composed of DFIG and two back to back PWM voltage source converters (VSCs in the rotor circuit. A machine model is derived in an appropriate dq reference frame. The grid voltage oriented vector control is used for the grid side converter (GSC in order to maintain a constant DC bus voltage, while the stator voltage orientated vector control is adopted in the rotor side converter (RSC to control the active and reactive powers.

  13. Smoothing of wind farm output power using prediction based flywheel energy storage system

    Science.gov (United States)

    Islam, Farzana

    Being socially beneficial, economically competitive and environment friendly, wind energy is now considered to be the world's fastest growing renewable energy source. However, the stochastic nature of wind imposes a considerable challenge in the optimal management and operation of wind power system. Wind speed prediction is critical for wind energy conversion system since it greatly influences the issues related to effective energy management, dynamic control of wind turbine, and improvement of the overall efficiency of the power generation system. This thesis focuses on integration of energy storage system with wind farm, considering wind speed prediction in the control scheme to overcome the problems associated with wind power fluctuations. In this thesis, flywheel energy storage system (FESS) with adjustable speed rotary machine has been considered for smoothing of output power in a wind farm composed of a fixed speed wind turbine generator (FSWTG). Since FESS has both active and reactive power compensation ability, it enhances the stability of the system effectively. An efficient energy management system combined with supervisory control unit (SCU) for FESS and wind speed prediction has been developed to improve the smoothing of the wind farm output effectively. Wind speed prediction model is developed by artificial neural network (ANN) which has advantages over the conventional prediction scheme including data error tolerance and ease in adaptability. The model for prediction with ANN is developed in MATLAB/Simulink and interfaced with PSCAD/EMTDC. Effectiveness of the proposed control system is illustrated using real wind speed data in various operating conditions.

  14. Control for Wind Power Generation Based on Inverse System Theory

    Directory of Open Access Journals (Sweden)

    Jiyong Zhang

    2013-11-01

    Full Text Available Traditional Double-fed Wind Generation systems are based on the vector control method, and it is dependent on motor parameters. The performance of the control system will be affected with the parameters changing,. This paper proposes a new control method based on inverse system and variable structure sliding mode(VSS theories, through the inverse system theory, the structure of its state’s equation, obtaining the structure of the inverse system, the establishment of Wind Power Generation closed-loop control system is established. The VSS controller, designed with exponential reaching law, can improve the dynamic performance in normal operation range effectively. When the system operates with variable speed constant frequency (VSCF and the phase voltage drops, the simulations show that the control system can control the DC link voltage steabily, maintain unity power factor, achieve the decoupling of the active and reactive power. And experiments show that the control method used in  VSCF wind power system is feasible.  

  15. Wind energy management for smart grids with storage systems

    Energy Technology Data Exchange (ETDEWEB)

    Gasco, Manuel [Universidad de Alicante (Spain). Area de Ingenieria Electrica; Rios, Alberto [Universidad Europea de Madrid (Spain). Area de Ingenieria Electrica

    2012-07-01

    Increasing integration of wind energy into the power system makes the optimal management of different situations that can occur more and more important. The objective of the present study is to replace the power necessary for electrical feed when the wind resources are not available, and to make a continuous demand tracking of the power. The energy storage systems treated in this study are as follows: a fuel cell, flywheel, pump systems and turbine systems, compressed air systems, electrochemical cells, electric vehicles, supercapacitors and superconductors. As a result the maximum benefit of the smart grid is achieved and it includes coexistence of the energy storage systems described and integrated in the numerous microgrids which can form the distribution grid. The current capacity is observed in order to be able to manage the wind generation for short periods of time. This way it is possible to plan the production which would be adjusted to the variations through these storage systems allowing the systems to maintain their constant programming for the base plants, adjusting the variations in these systems in the short term. (orig.)

  16. Cooperative field test program for wind systems. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Bollmeier, W.S. II; Dodge, D.M.

    1992-03-01

    The objectives of the Federal Wind Energy Program, managed by the US Department of Energy (DOE), are (1) to assist industry and utilities in achieving a multi-regional US market penetration of wind systems, and (2) to establish the United States as the world leader in the development of advanced wind turbine technology. In 1984, the program conducted a series of planning workshops with representatives from the wind energy industry to obtain input on the Five-Year Research Plan then being prepared by DOE. One specific suggestion that came out of these meetings was that the federal program should conduct cooperative research tests with industry to enhance the technology transfer process. It was also felt that the active involvement of industry in DOE-funded research would improve the state of the art of wind turbine technology. DOE established the Cooperative Field Test Program (CFTP) in response to that suggestion. This program was one of the first in DOE to feature joint industry-government research test teams working toward common objectives.

  17. Power Quality Improvement Wind Energy System Using Cascaded Multilevel Inverter

    Directory of Open Access Journals (Sweden)

    J.S. Sathiyanarayanan

    2013-02-01

    Full Text Available In this paper, a wind energy conversion system based on a cascaded H-bridgemultilevel inverter (CHBMLI topology has been proposed to be used for the grid interface of largesplit winding alternators (SWAs. A new method has been suggested for the generation of referencecurrents for the voltage source inverter (VSI depending upon the available wind power. TheCHBMLI has been used as a VSI and operated in a current control mode order to achieve theobjectives of real power injection and load compensation (power factor correction, load balancing,and harmonic compensation based on the proposed reference generation scheme. In the fieldexcitation control of SWA provides a single means vary the dc link voltages of all the CHBssimultaneously and proportionately.

  18. Short term fluctuations of wind and solar power systems

    CERN Document Server

    Anvari, M; Wächter, M; Milan, P; Lorenz, E; Heinemann, D; Tabar, M Reza Rahimi; Peinke, Joachim

    2016-01-01

    Wind and solar power are known to be highly influenced by weather events and may ramp up or down abruptly. Such events in the power production influence not only the availability of energy, but also the stability of the entire power grid. By analysing significant amounts of data from several regions around the world with resolutions of seconds to minutes, we provide strong evidence that renewable wind and solar sources exhibit multiple types of variability and nonlinearity in the time scale of {\\it seconds} and characterise their stochastic properties. In contrast to previous findings, we show that only the jumpy characteristic of renewable sources decreases when increasing the spatial size over which the renewable energies are harvested. Otherwise, the strong non-Gaussian, intermittent behaviour in the cumulative power of the total field survives even for a country-wide distribution of the systems. The strong fluctuating behaviour of renewable wind and solar sources can be well characterised by Kolmogorov-li...

  19. The Value of Wind Technology Innovation: Implications for the U.S. Power System, Wind Industry, Electricity Consumers, and Environment

    Energy Technology Data Exchange (ETDEWEB)

    Mai, Trieu T [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Lantz, Eric J [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Mowers, Matthew [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Wiser, Ryan [Lawrence Livermore National Laboratory

    2017-09-21

    Improvements to wind technologies have, in part, led to substantial deployment of U.S. wind power in recent years. The degree to which technology innovation will continue is highly uncertain adding to uncertainties in future wind deployment. We apply electric sector modeling to estimate the potential wind deployment opportunities across a range of technology advancement projections. The suite of projections considered span a wide range of possible cost and technology innovation trajectories, including those from a recent expert elicitation of wind energy experts, a projection based on the broader literature, and one reflecting estimates based on a U.S. DOE research initiative. In addition, we explore how these deployment pathways may impact the electricity system, electricity consumers, the environment, and the wind-related workforce. Overall, our analysis finds that wind technology innovation can have consequential implications for future wind power development throughout the United States, impact the broader electricity system, lower electric system and consumer costs, provide potential environmental benefits, and grow the U.S. wind workforce.

  20. Overview of DFIG-based Wind Power System Resonances under Weak Networks

    DEFF Research Database (Denmark)

    Song, Yipeng; Blaabjerg, Frede

    2017-01-01

    The wind power generation techniques are continuing to develop and increasing numbers of Doubly Fed Induction Generator (DFIG)-based wind power systems are connecting to the on-shore and off-shore grids, local standalone weak networks, and also micro grid applications. The impedances of the weak...... weak network respectively. This paper will discuss the SSR and the HFR phenomena based on the impedance modeling of the DFIG system and the weak networks, and the cause of these two resonances will be explained in details. The following factors including 1) transformer configuration; 2) different power...... networks are too large to be neglected and require careful attention. Due to the impedance interaction between the weak network and the DFIG system, both Sub- Synchronous Resonance (SSR) and High Frequency Resonance (HFR) may occur when the DFIG system is connected to the series or parallel compensated...

  1. 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.

  2. A design of vertical axis wind power generating system combined with Darrieus-Savonius for adaptation of variable wind speed

    Energy Technology Data Exchange (ETDEWEB)

    Seo, Young Taek; Oh, Chul Soo [Kyung Pook National University, Taegu (Korea, Republic of)

    1996-02-01

    This paper presents a design of vertical axis Darrieus wind turbine combined with Savonius for wind-power generating system to be adapted for variable wind speed. The wind turbine consists of two troposkien- and four Savonius-blades. Darrieus turbine is designed with diameter 9.4[m], chord length 380[mm], tip speed ratio 5. Savonius turbine is designed with diameter 1.8[m], height 2[m], tip speed ratio 0.95. The design of turbine is laid for the main data of rated wind speed 10[m/s], turbine speed 101.4[rpm]. The generating power is estimated to maximum power 20[kWh], and this is converted to commercial power line by means of three phase synchronous generator-inverter system. Generating system is designed for operation on VSVF(variable speed variable frequency) condition and constant voltage system. (author). 11 refs., 14 figs.

  3. Wind energy systems control engineering design

    CERN Document Server

    Garcia-Sanz, Mario

    2012-01-01

    IntroductionBroad Context and MotivationConcurrent Engineering: A Road Map for EnergyQuantitative Robust ControlNovel CAD Toolbox for QFT Controller DesignOutline Part I: Advanced Robust Control Techniques: QFT and Nonlinear SwitchingIntroduction to QFTQuantitative Feedback TheoryWhy Feedback? QFT OverviewInsight into the QFT TechniqueBenefits of QFTMISO Analog QFT Control SystemIntroductionQFT Method (Single-Loop MISO System)Design Procedure OutlineMinimum-Phase System Performance SpecificationsJ LTI Plant ModelsPlant Templates of P?(s), P( j_i )Nominal PlantU-Contour (Stability Bound)Trackin

  4. Pickup Ion Effect of the Solar Wind Interaction with the Local Interstellar Medium

    CERN Document Server

    Pogorelov, Nikolai V; Kryukov, Igor A; Zank, Gary P

    2016-01-01

    Pickup ions are created when interstellar neutral atoms resonantly exchange charge with the solar wind (SW) ions, especially in the supersonic part of the wind, where they carry most of the plasma pressure. Here we present numerical simulation results of the 3D heliospheric interface treating pickup ions as a separate proton fluid. To satisfy the fundamental conservation laws, we solve the system of equations describing the flow of the mixture of electrons, thermal protons, and pickup ions. To find the density and pressure of pickup ions behind the termination shock, we employ simple boundary conditions that take into account the \\emph{Voyager} observations that showed that the decrease in the kinetic energy of the mixture at the termination shock predominantly contributed to the increase in the pressure of pickup ions. We show that this model adequately describes the flow of the plasma mixture and results in a noticeable decrease in the heliosheath width.

  5. Pickup Ion Effect of the Solar Wind Interaction with the Local Interstellar Medium

    Science.gov (United States)

    Pogorelov, N. V.; Bedford, M. C.; Kryukov, I. A.; Zank, G. P.

    2016-11-01

    Pickup ions are created when interstellar neutral atoms resonantly exchange charge with the solar wind (SW) ions, especially in the supersonic part of the wind, where they carry most of the plasma pressure. Here we present numerical simulation results of the 3D heliospheric interface treating pickup ions as a separate proton fluid. To satisfy the fundamental conservation laws, we solve the system of equations describing the flow of the mixture of electrons, thermal protons, and pickup ions. To find the density and pressure of pickup ions behind the termination shock, we employ simple boundary conditions that take into account the Voyager observations that showed that the decrease in the kinetic energy of the mixture at the termination shock predominantly contributed to the increase in the pressure of pickup ions. We show that this model adequately describes the flow of the plasma mixture and results in a noticeable decrease in the heliosheath width.

  6. Increasing wind energy penetration level using pumped hydro storage in island micro-grid system

    Energy Technology Data Exchange (ETDEWEB)

    Islam, Sheikh Mominul [Memorial Univ. of Newfoundland, St. John' s, NL (Canada). Dept. of Engineering

    2012-07-01

    Ramea is a small island in southern Newfoundland. Since 2004, it has a wind-diesel hybrid power system to provide power for approximately 600 inhabitants. In this paper, wind speed data, load data, and sizing of pumped hydro system at Ramea, Newfoundland are presented. The dynamic model of wind turbine, pumped hydro system, and diesel generator are included in this paper. The dynamic model is simulated in SIMULINK/MATLAB to determine the system voltage and frequency variation and also to visualize different power outputs. Sizing of pumped hydro system indicates that a 150-kW pumped hydro storage system can be installed in Ramea to increase the renewable energy fraction to 37% which will reduce non-renewable fuel consumption on this island. Also, it is found that a pumped hydro energy storage system for Ramea is a much better choice than a hydrogen energy storage system. Such a system will have a higher overall efficiency and could be maintained using local technical expertise, therefore, a more appropriate technology for Ramea. (orig.)

  7. Dynamic modelling and robust control of a wind energy conversion system

    NARCIS (Netherlands)

    Steinbuch, M.

    1989-01-01

    The application of wind energy conversion systems for the production of electrical energy requires a cheap and reliable operation. Especially at high wind velocities fluctuations from the wind field result in large mechanical loads of the wind turbine. Also fluctuations in the grid voltage may yield

  8. System reliability effects in wind turbine blades

    DEFF Research Database (Denmark)

    Dimitrov, Nikolay Krasimirov; Friis-Hansen, Peter; Berggreen, Christian

    2012-01-01

    Laminated composite sandwich panels have a layered structure, where individual layers have randomly varying stiffness and strength properties. The presence of multiple failure modes and load redistribution following partial failures are the reason for laminated composites to exhibit system behavior...

  9. Pressure-Sensitive Paint and Video Model Deformation Systems at the NASA Langley Unitary Plan Wind Tunnel

    Science.gov (United States)

    Erickson, G. E.; Burner, A. W.; DeLoach, R.

    1999-01-01

    Pressure-sensitive paint (PSP) and video model deformation (VMD) systems have been installed in the Unitary Plan Wind Tunnel at the NASA Langley Research Center to support the supersonic wind tunnel testing requirements of the High Speed Research (HSR) program. The PSP and VMD systems have been operational since early 1996 and provide the capabilities of measuring global surface static pressures and wing local twist angles and deflections (bending). These techniques have been successfully applied to several HSR wind tunnel models for wide ranges of the Mach number, Reynolds number, and angle of attack. A review of the UPWT PSP and VMD systems is provided, and representative results obtained on selected HSR models are shown. A promising technique to streamline the wind tunnel testing process, Modern Experimental Design, is also discussed in conjunction with recently-completed wing deformation measurements at UPWT.

  10. Integration of Wind Energy, Hydrogen and Natural Gas Pipeline Systems to Meet Community and Transportation Energy Needs: A Parametric Study

    Directory of Open Access Journals (Sweden)

    Shahryar Garmsiri

    2014-04-01

    Full Text Available The potential benefits are examined of the “Power-to-Gas” (P2G scheme to utilize excess wind power capacity by generating hydrogen (or potentially methane for use in the natural gas distribution grid. A parametric analysis is used to determine the feasibility and size of systems producing hydrogen that would be injected into the natural gas grid. Specifically, wind farms located in southwestern Ontario, Canada are considered. Infrastructure requirements, wind farm size, pipeline capacity, geographical dispersion, hydrogen production rate, capital and operating costs are used as performance measures. The model takes into account the potential production rate of hydrogen and the rate that it can be injected into the local gas grid. “Straw man” systems are examined, centered on a wind farm size of 100 MW integrating a 16-MW capacity electrolysis system typically producing 4700 kg of hydrogen per day.

  11. Stability and control of wind farms in power systems

    DEFF Research Database (Denmark)

    Jauch, Clemens

    oscillating power injection can only be realised by controlling the pitch angle.Hence the power system stabiliser of an active-stall turbine is a pitch angle controller. Two different approaches are chosen for designing such a power system stabiliser: a conventional PID controller, and a fuzzy logic...... is part of the project. The mostextensive modelling work deals with the design of the electrical part of the variable speed turbine and its controls. To simulate realistic grid operation the wind turbine models are connected to an aggregated model of the Nordic power system. For thatpurpose the Nordic...... power system model, which was available prior to the project, is extended with a realistic feeder configuration. It is commonly demanded from modern wind turbines, that they must not disconnect in case of transient faults. Therefore,controllers are designed that enable the two turbine types to ride...

  12. Economic Operation of Power Systems with Significant Wind Power Penetration

    DEFF Research Database (Denmark)

    Farashbashi-Astaneh, Seyed-Mostafa

    This dissertation addresses economic operation of power systems with high penetration of wind power. Several studies are presented to address the economic operation of power systems with high penetration of variable wind power. The main concern in such power systems is high variability...... level should be economic and can be a provided by different tools such as developing new reserve scheduling techniques, demand response, using storage units, facilitating the capacity of cross-border interconnections and so on. These subjects are addressed in this PhD dissertation. In the first study...... (and thus power system security is enhanced). The optimal charging scheme of Eclectic Vehicles (EVs) in a distribution feeder is then studied considering the proposed pricing scheme. A formulation is then proposed for optimal reserve scheduling considering the role of reserve provision scenarios from...

  13. Photovoltaic-wind hybrid system for permanent magnet DC motor

    Science.gov (United States)

    Nasir, M. N. M.; Lada, M. Y.; Baharom, M. F.; Jaafar, H. I.; Ramani, A. N.; Sulaima, M. F.

    2015-05-01

    Hybrid system of Photovoltaic (PV) - Wind turbine (WT) generation has more advantages and reliable compared to PV or wind turbine system alone. The aim of this paper is to model and design hybrid system of PV-WT supplying 100W permanent-magnet dc motor. To achieve the objective, both of PV and WT are connected to converter in order to get the same source of DC supply. Then both sources were combined and straightly connected to 100W permanent magnet dc motor. All the works in this paper is only applied in circuit simulator by using Matlab Simulink. The output produced from each converter is expected to be suit to the motor specification. The output produced from each renewable energy system is as expected to be high as it can support the motor if one of them is breakdown

  14. Integration of wind power for optimal power system black-start restoration

    OpenAIRE

    ZONKOLY, AMANY EL

    2015-01-01

    Integration of wind farms into power systems may increase the risk of power system blackouts due to the uncertain nature of their output power. In the meantime, wind turbines have relatively short starting time when compared to non-black-start (NBS) generating units. For this reason, wind farms need to participate in power system restoration after blackouts. The decision of restoring a wind farm depends on its output power and the characteristics of the power system. The power system restorat...

  15. A Wind Power and Load Prediction Based Frequency Control Approach for Wind-Diesel-Battery Hybrid Power System

    Directory of Open Access Journals (Sweden)

    Chao Peng

    2015-01-01

    Full Text Available A frequency control approach based on wind power and load power prediction information is proposed for wind-diesel-battery hybrid power system (WDBHPS. To maintain the frequency stability by wind power and diesel generation as much as possible, a fuzzy control theory based wind and diesel power control module is designed according to wind power and load prediction information. To compensate frequency fluctuation in real time and enhance system disturbance rejection ability, a battery energy storage system real-time control module is designed based on ADRC (active disturbance rejection control. The simulation experiment results demonstrate that the proposed approach has a better disturbance rejection ability and frequency control performance compared with the traditional droop control approach.

  16. The Low-Level Wind Shear Alert System (LLWSAS)

    Science.gov (United States)

    1980-05-01

    known overshooting problems of cup -type anemometers such as the model F-420, the NWS sensor has far more severe damping characteristics than the LLWSAS...the Low-Level Wind Shear Alert System (LLWSAS) field test and evalua- tion are reported. The system is a computer controlled anemometer mesonetwork...Hardware 17 LLWSAS Software 46 Anemometer Siting Criteria 64 LLWSAS Data Collection and Analysis 88 Airport Sensor Configurations, Special Siting Factors

  17. Modeling Feasibility of a Proposed Renewable Energy System with Wind and Solar Resources and Hydro Storage in Complex Terrain

    Science.gov (United States)

    Jiang, J.; Koracin, D.; Hamilton, R.; Hagen, D.; King, K. C.

    2012-04-01

    High temporal and spatial variability in wind and solar power brings difficulties in integrating these resources into an electricity grid. These difficulties are even more emphasized in areas with complex topography due to complicated flow patterns and cloudiness evolution. This study investigates the feasibility and efficiency of a proposed renewable energy system with wind and solar resources and hydro storages in western Nevada, U.S.A. The state-of-the-art Weather Research and Forecasting (WRF) model was used for the prediction of wind fields and incoming solar radiation at the ground surface. Forecast winds and solar radiation were evaluated with observational data from four wind masts and four meteorological towers in two months, July 2007 and January 2010. Based on a hypothetical wind farm and an assumed neighboring solar power plant both located near the hydro storage facility, as well as considering local power demand, the efficiency of the renewable energy system is projected. One of the main questions was how to optimize a schedule of activating pump storages according to the characteristics of several available hydro pumps, and wind and/or solar power predictions. The results show that segmentation of the pump-storage channel provides improved efficiency of the entire system. This modeled renewable energy system shows promise for possible applications and grid integration.

  18. Modelisation et simulation d'un systeme de jumelage eolien-diesel alimentant une charge locale

    Science.gov (United States)

    Theubou Tameghe, Tommy Andy

    This thesis focuses on the modeling of a wind-diesel cogeneration system feeding a local load. The proposed system implements a wind turbine, connected to a diesel generator that supplies an electrical load. Such a system is commonly used in remote areas and allows the reduction of the diesel energy production. This yields a reduction of pollution and production costs of the electrical energy. At first, this report describes the socio-economic context and motivations of the subject. Thereafter, are inventoried the main technical issues related to wind-diesel cogeneration plants. To better meet the objectives of this work, study and mode ling of the system are organized into four key points: (1) a literature review based on general concepts related to wind-diesel systems and mathematical/numerical analysis tools; (2) the analysis and modeling of diesel generator, (3) of the wind turbine; (4) and finally, the interconnection of wind and diesel generators. Each point describes the dynamic equations, organized in the form of state model or transfer function, of the considered subsystem. Developed dynamic models were simulated using Matlab / Simulink. Typical values, commonly used in the literature, were used. Due to the lack of records and technical data on existing specific wind-diesel system, developed models were cross-validated, comparing the simulation results with those from the literature.

  19. Wind energy conversion system analysis model (WECSAM) computer program documentation

    Energy Technology Data Exchange (ETDEWEB)

    Downey, W T; Hendrick, P L

    1982-07-01

    Described is a computer-based wind energy conversion system analysis model (WECSAM) developed to predict the technical and economic performance of wind energy conversion systems (WECS). The model is written in CDC FORTRAN V. The version described accesses a data base containing wind resource data, application loads, WECS performance characteristics, utility rates, state taxes, and state subsidies for a six state region (Minnesota, Michigan, Wisconsin, Illinois, Ohio, and Indiana). The model is designed for analysis at the county level. The computer model includes a technical performance module and an economic evaluation module. The modules can be run separately or together. The model can be run for any single user-selected county within the region or looped automatically through all counties within the region. In addition, the model has a restart capability that allows the user to modify any data-base value written to a scratch file prior to the technical or economic evaluation. Thus, any user-supplied data for WECS performance, application load, utility rates, or wind resource may be entered into the scratch file to override the default data-base value. After the model and the inputs required from the user and derived from the data base are described, the model output and the various output options that can be exercised by the user are detailed. The general operation is set forth and suggestions are made for efficient modes of operation. Sample listings of various input, output, and data-base files are appended. (LEW)

  20. Three Sides Billboard Wind-Solar Hybrid System Design

    Directory of Open Access Journals (Sweden)

    Bai Xuefeng

    2015-01-01

    Full Text Available With the high development of world economy, the demand of energy is increasing all the time, As energy shortage and environment problem are increasing outstanding, Renewable energy has been attracting more and more attention. A kind of three sides billboard supply by wind-Solar hybrid system has been designed in this paper, the overall structure of the system, components, working principle and control strategy has been analyzed from the system perspective. The software and hardware of the system are debugged together and the result is acquired. System function is better and has achieved the expected results.

  1. Photovoltaics and Wind Power Systems. Course Syllabus.

    Science.gov (United States)

    Bergen County Vocational-Technical High School, Hackensack, NJ.

    This course is one of four in a solar systems and energy management program developed by the Bergen County Vocational-Technical Schools to help tradespeople (heating, ventilation, and air conditioning mechanics; plumbers; and electricians) to develop an awareness of alternate energy sources and to gain skills in the areas of solar installations…

  2. Structured Control of LPV Systems with Application to Wind Turbines

    DEFF Research Database (Denmark)

    Adegas, Fabiano Daher; Stoustrup, Jakob

    2012-01-01

    can synthesize structured controllers like decentralized, static output and reduced order output feedback for discrete-time LPV systems. Based on a coordinate decent, it relies on a sufficient matrix inequality condition extended with slack variables to an upper bound on the induced L2-norm...... of the closed-loop system. Algorithms for the computation of feasible as well as optimal controllers are presented. The general case where no restrictions are imposed on the parameter dependence is treated here due to its suitability for modeling wind turbines. A comprehensive numerical example of a gain......This paper deals with structured control of linear parameter varying systems (LPV) with application to wind turbines. Instead of attempting to reduce the problem to linear matrix inequalities (LMI), we propose to design the controllers via an LMI-based iterative algorithm. The proposed algorithm...

  3. Optimization of Multibrid Permanent-Magnet Wind Generator Systems

    DEFF Research Database (Denmark)

    Chen, Zhe; Li, H.; Polinder, H.

    2009-01-01

    This paper investigates the cost-effective ranges of gearbox ratios and power ratings of multibrid permanent-magnet (PM) wind generator systems by using a design optimization method. First, the analytical model of a multibrid wind turbine concept consisting of a single-stage gearbox and a three......-phase radial-flux PM synchronous generator with a back-to-back power converter is presented. The design optimization is adopted with a genetic algorithm forminimizing generator system cost. To demonstrate the effectiveness of the developed electromagnetic design model, the optimization results of a 500-k......W direct-drive PM generator and a 1.5-MW multibrid PM generator with various gear ratios are, respectively, compared with those from other methods. Then, the optimal design approach is further employed for a range from 750 kW up to 10 MW. The optimization results of PM generator systems including direct...

  4. Wind Power Ramping Product for Increasing Power System Flexibility

    Energy Technology Data Exchange (ETDEWEB)

    Cui, Mingjian; Zhang, Jie; Wu, Hongyu; Hodge, Bri-Mathias; Ke, Deping; Sun, Yuanzhang

    2016-05-05

    With increasing penetrations of wind power, system operators are concerned about a potential lack of system flexibility and ramping capacity in real-time dispatch stages. In this paper, a modified dispatch formulation is proposed considering the wind power ramping product (WPRP). A swinging door algorithm (SDA) and dynamic programming are combined and used to detect WPRPs in the next scheduling periods. The detected WPRPs are included in the unit commitment (UC) formulation considering ramping capacity limits, active power limits, and flexible ramping requirements. The modified formulation is solved by mixed integer linear programming. Numerical simulations on a modified PJM 5-bus System show the effectiveness of the model considering WPRP, which not only reduces the production cost but also does not affect the generation schedules of thermal units.

  5. Efficient operation of anisotropic synchronous machines for wind energy systems

    Science.gov (United States)

    Eldeeb, Hisham; Hackf, Christoph M.; Kullick, Julian

    2016-09-01

    This paper presents an analytical solution for the Maximum-Torque-per-Ampere (MTPA) operation of synchronous machines (SM) with anisotropy and magnetic cross-coupling for the application in wind turbine systems and airborne wind energy systems. For a given reference torque, the analytical MTPA solution provides the optimal stator current references which produce the desired torque while minimizing the stator copper losses. From an implementation point of view, the proposed analytical method is appealing in terms of its fast online computation (compared to classical numerical methods) and its efficiency enhancement of the electrical drive system. The efficiency of the analytical MTPA operation, with and without consideration of cross-coupling, is compared to the conventional method with zero direct current.

  6. Energy Storage Systems as a Compliment to Wind Power

    Science.gov (United States)

    Sieling, Jared D.; Niederriter, C. F.; Berg, D. A.

    2006-12-01

    As Gustavus Adolphus College prepares to install two wind turbines on campus, we are faced with the question of what to do with the excess electricity that is generated. Since the College pays a substantial demand charge, it would seem fiscally responsible to store the energy and use it for peak shaving, instead of selling it to the power company at their avoided cost. We analyzed six currently available systems: hydrogen energy storage, flywheels, pumped hydroelectric storage, battery storage, compressed air storage, and superconducting magnetic energy storage, for energy and financial suitability. Potential wind turbine production is compared to consumption to determine the energy deficit or excess, which is fed into a model for each of the storage systems. We will discuss the advantages and disadvantages of each of the storage systems and their suitability for energy storage and peak shaving in this situation.

  7. Wind speed forecasting for wind energy applications

    Science.gov (United States)

    Liu, Hong

    With more wind energy being integrated into our grid systems, forecasting wind energy has become a necessity for all market participants. Recognizing the market demands, a physical approach to site-specific hub-height wind speed forecasting system has been developed. This system is driven by the outputs from the Canadian Global Environmental Multiscale (GEM) model. A simple interpolation approach benchmarks the forecasting accuracy inherited from GEM. Local, site specific winds are affected on a local scale by a variety of factors including representation of the land surface and local boundary-layer process over heterogeneous terrain which have been a continuing challenge in NWP models like GEM with typical horizontal resolution of order 15-km. In order to resolve these small scale effects, a wind energy industry standard model, WAsP, is coupled with GEM to improve the forecast. Coupling the WAsP model with GEM improves the overall forecasts, but remains unsatisfactory for forecasting winds with abrupt surface condition changes. Subsequently in this study, a new coupler that uses a 2-D RANS model of boundary-layer flow over surface condition changes with improved physics has been developed to further improve the forecasts when winds coming from a water surface to land experience abrupt changes in surface conditions. It has been demonstrated that using vertically averaged wind speeds to represent geostrophic winds for input into the micro-scale models could reduce forecast errors. The hub-height wind speed forecasts could be further improved using a linear MOS approach. The forecasting system has been evaluated, using a wind energy standard evaluation matrix, against data from an 80-m mast located near the north shore of Lake Erie. Coupling with GEM-LAM and a power conversion model using a theoretical power curve have also been investigated. For hub-height wind speeds GEM appears to perform better with a 15-Ian grid than the high resolution GEM-2.5Ian version at the

  8. Impact of Wind Power on the Angular Stability of a Power System

    Directory of Open Access Journals (Sweden)

    Djemai NAIMI

    2008-06-01

    Full Text Available Wind energy conversion systems are very different in nature from conventional generators. Therefore dynamic studies must be addressed in order to integrate wind power into the power system. Angular stability assessment of wind power generator is one of main issues in power system security and operation. The angular stability for the wind power generator is determined by its corresponding Critical Clearing Time (CCT. In this paper, the effect of wind power on the transient fault behavior is investigated by replacing the power generated by two main types of wind turbine, increasing gradually a rate of wind power penetration and changing the location of wind resources. The simulation analysis was established on a 14 bus IEEE test system by PSAT/Matlab, which gives access to an extensive library of grid components, and relevant wind turbine model.

  9. Advanced Recovery Systems Wind Tunnel Test Report

    Science.gov (United States)

    1990-08-01

    120’ leg is basically an open circuit tunnel with a closed throat test section (Figure 4.1-1). The 135,000 horse power fan drive system is enough to... AMpAcs (c.g.) = WPACSL sin(ap + ,) This methodology was applied to all the data and the induced moment, due to the offset in the PACS c.g., was removed...around wires and cables . Figure 5.3-3 depicts the nomenclature for the Cross Flow Principle. To determine CD the following equations are used: Co1 = 1.10

  10. Wind turbine control systems: Dynamic model development using system identification and the fast structural dynamics code

    Energy Technology Data Exchange (ETDEWEB)

    Stuart, J.G.; Wright, A.D.; Butterfield, C.P.

    1996-10-01

    Mitigating the effects of damaging wind turbine loads and responses extends the lifetime of the turbine and, consequently, reduces the associated Cost of Energy (COE). Active control of aerodynamic devices is one option for achieving wind turbine load mitigation. Generally speaking, control system design and analysis requires a reasonable dynamic model of {open_quotes}plant,{close_quotes} (i.e., the system being controlled). This paper extends the wind turbine aileron control research, previously conducted at the National Wind Technology Center (NWTC), by presenting a more detailed development of the wind turbine dynamic model. In prior research, active aileron control designs were implemented in an existing wind turbine structural dynamics code, FAST (Fatigue, Aerodynamics, Structures, and Turbulence). In this paper, the FAST code is used, in conjunction with system identification, to generate a wind turbine dynamic model for use in active aileron control system design. The FAST code is described and an overview of the system identification technique is presented. An aileron control case study is used to demonstrate this modeling technique. The results of the case study are then used to propose ideas for generalizing this technique for creating dynamic models for other wind turbine control applications.

  11. The role of technology transfer for the development of a local wind component industry in Chile

    Energy Technology Data Exchange (ETDEWEB)

    Pueyo, Ana, E-mail: anapueyo@hotmail.com [Technical University of Madrid (UPM)-Escuela Tecnica Superior de Ingenieros Industriales (ETSII), Madrid (Spain); Garcia, Rodrigo [Centro de Energias Renovables (CER), Santiago de Chile (Chile); Mendiluce, Maria [World Business Council for Sustainable Development (WBCSD), Geneva (Switzerland); Morales, Dario [InnovaChile-CORFO Chile, Santiago de Chile (Chile)

    2011-07-15

    This paper contributes to the debate about climate change technology transfer by analysing barriers and enablers for a Chilean company starting up the production of wind blades. Literature on the role of technology transfer for the development and deployment of local renewable energy technologies in developing countries often refers to success stories in Brazil, India and China. Instead, this case study highlights the different challenges faced by smaller emerging economies. The paper argues that successful technology transfer in a smaller economy like Chile requires: a minimum internal demand and access to regional markets to attract foreign knowledge providers; a focus in the types of technologies where the recipient country or company have a competitive advantage; and active learning processes by the recipient company. Lessons are drawn for improving the design and implementation of technology-push and market-pull policies in small or medium emerging economies. - Highlights: > We analyse the case of a Chilean company starting up wind blades production. > Technology transfer is required as the relevant knowledge is not available in the country. > We examine the factors that enable technology transfer to draw policy conclusions. > We highlight the particularities of medium sized developing countries.

  12. Space Shuttle Damper System for Ground Wind Load Tests

    Science.gov (United States)

    Robinson, G. D.; Holt, J. R.; Chang, C. S.

    1973-01-01

    An active damper system which was originally developed for a 5.5% Saturn IB/Skylab Ground Winds Model was modified and used for similar purposes in a Space Shuttle model. A second damper system which was originally used in a 3% Saturn V/Dry Workshop model was also modified and made compatible with the Space Shuttle model to serve as a back-up system. Included in this final report are descriptions of the modified damper systems and the associated control and instrumentation.

  13. Statistical analysis and dimensioning of a wind farm energy storage system

    Directory of Open Access Journals (Sweden)

    Waśkowicz Bartosz

    2017-06-01

    Full Text Available The growth in renewable power generation and more strict local regulations regarding power quality indices will make it necessary to use energy storage systems with renewable power plants in the near future. The capacity of storage systems can be determined using different methods most of which can be divided into either deterministic or stochastic. Deterministic methods are often complicated with numerous parameters and complex models for long term prediction often incorporating meteorological data. Stochastic methods use statistics for ESS (Energy Storage System sizing, which is somewhat intuitive for dealing with the random element of wind speed variation. The proposed method in this paper performs stabilization of output power at one minute intervals to reduce the negative influence of the wind farm on the power grid in order to meet local regulations. This paper shows the process of sizing the ESS for two selected wind farms, based on their levels of variation in generated power and also, for each, how the negative influences on the power grid in the form of voltage variation and a shortterm flicker factor are decreased.

  14. Impacts of coastal upwelling off east Vietnam on the regional winds system: An air-sea-land interaction

    Science.gov (United States)

    Zheng, Zhe-Wen; Zheng, Quanan; Kuo, Yi-Chun; Gopalakrishnan, Ganesh; Lee, Chia-Ying; Ho, Chung-Ru; Kuo, Nan-Jung; Huang, Shih-Jen

    2016-12-01

    In this study, we analyze the influence of coastal upwelling off southeast Vietnam (CUEV) on local wind field using numerical simulations based on atmospheric model of Weather Research and Forecasting (WRF). Several scenarios are simulated by forcing identical model configurations with different SST fields. Based on simulation results, the relationship between CUEV and reduction of wind forcing is numerically evidenced. With the influence of a typical cold patch with a temperature drop of 3-5 °C, the local wind speeds can drop to less than 70% of original level. We find that the mechanism of response of the wind reduction to CUEV is enhancement of sea-breeze induced wind modulation. Onshore sea-breeze will enhance, while the contrast between land and sea is even more striking due to the contribution of a distinct coastal upwelling. This implies that air-sea-land interaction dominates the process of local wind system modulation in response to transient CUEV. This result sheds a new light on the air-sea interaction process within the SCS basin.

  15. Safety systems for the ESES 2002 wind pump

    Energy Technology Data Exchange (ETDEWEB)

    El Agamawy, H. [Engine Factory, Doki (Egypt)

    2001-07-01

    The ESES 2002 wind pump, a 4.6 m rotor diameter high-performance water pumping windmill, was tested at four different sites (Cairo, Giza, Wadi El Natroun and El-Tor city on the Red Sea coast) from September 1997 to July 1999. These machines utilize a 3:1 gearbox and a hydrodynamic sealing piston pump. These four ESES 2002 wind pumps were tested by pumping from a motionless water depth of 3 in up to an 84 m deep well. A variety of pump diameter sizes varying from 64 to 1400 mm were used. The water pumped was returned to the well after flowing through a settling storage tank having a capacity of 3 m{sup 3}. The instrumentation provided a 16 channel data acquisition system to accurately measure the machine performance, including rotor rpm, number of stroke, starting wind speed, flow rate, tail furl angle and other variables. The results verify that the ESES 2002 wind pump is a robust machine as two machines have been running for 2 years continuously without requiring any replacement parts or major or minor maintenance. (author)

  16. Control of wind turbine generators connected to power systems

    Science.gov (United States)

    Hwang, H. H.; Mozeico, H. V.; Gilbert, L. J.

    1978-01-01

    A unique simulation model based on a Mode-O wind turbine is developed for simulating both speed and power control. An analytical representation for a wind turbine that employs blade pitch angle feedback control is presented, and a mathematical model is formulated. For Mode-O serving as a practical case study, results of a computer simulation of the model as applied to the problems of synchronization and dynamic stability are provided. It is shown that the speed and output of a wind turbine can be satisfactorily controlled within reasonable limits by employing the existing blade pitch control system under specified conditions. For power control, an additional excitation control is required so that the terminal voltage, output power factor, and armature current can be held within narrow limits. As a result, the variation of torque angle is limited even if speed control is not implemented simultaneously with power control. Design features of the ERDA/NASA 100-kW Mode-O wind turbine are included.

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

    DEFF Research Database (Denmark)

    Lin, Jin; Sun, Yuanzhang; Song, Yonghua

    2013-01-01

    loss, this paper designs a risk assessment model of grid frequency deviation, which is capable of locally estimating the maximum grid frequency deviation risk of the next dispatch cycle. A wind turbine speed optimizer then uses the estimated frequency deviation risk to search for the optimal power......Wind power fluctuation raises the security concern of grid frequency deviation, especially for an isolated power system. Thus, better control methodology needs to be developed to smooth the fluctuation without excessive spillage. Based on an actual industrial power system, this paper proposes...... a smoothing controller to suppress the power fluctuation from doubly-fed induction generator (DFIG)-based wind farm. This controller consists of threemain functionality components: risk assessmentmodel, wind turbine rotor speed optimizer, and rotor speed upper limiter. In order to avoid unnecessary energy...

  18. 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

    of operation. The participation of the WT mechanical system in the inter-area modes were found to be orders of magnitudes smaller than the participation of the synchronous generators. The reactive power controller of the WPP and the WT were found have the highest participation among the WPP and WT states. WPPs......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...

  19. Technical analysis of photovoltaic/wind systems with hydrogen storage

    Directory of Open Access Journals (Sweden)

    Bakić Vukman V.

    2012-01-01

    Full Text Available The technical analysis of a hybrid wind-photovoltaic energy system with hydrogen gas storage was studied. The market for the distributed power generation based on renewable energy is increasing, particularly for the standalone mini-grid applications. The main design components of PV/Wind hybrid system are the PV panels, the wind turbine and an alkaline electrolyzer with tank. The technical analysis is based on the transient system simulation program TRNSYS 16. The study is realized using the meteorological data for a Typical Metrological Year (TMY for region of Novi Sad, Belgrade cities and Kopaonik national park in Serbia. The purpose of the study is to design a realistic energy system that maximizes the use of renewable energy and minimizes the use of fossil fuels. The reduction in the CO2 emissions is also analyzed in the paper. [Acknowledgment. This paper is the result of the investigations carried out within the scientific project TR33036 supported by the Ministry of Science of the Republic of Serbia.

  20. Global Auroral Energy Deposition during Substorm Onset Compared with Local Time and Solar Wind IMF Conditions

    Science.gov (United States)

    Spann, J. F.; Brittnacher, M.; Fillingim, M. O.; Germany, G. A.; Parks, G. K.

    1998-01-01

    The global images made by the Ultraviolet Imager (UVI) aboard the IASTP/Polar Satellite are used to derive the global auroral energy deposited in the ionosphere resulting from electron precipitation. During a substorm onset, the energy deposited and its location in local time are compared to the solar wind IMF conditions. Previously, insitu measurements of low orbiting satellites have made precipitating particle measurements along the spacecraft track and global images of the auroral zone, without the ability to quantify energy parameters, have been available. However, usage of the high temporal, spatial, and spectral resolution of consecutive UVI images enables quantitative measurement of the energy deposited in the ionosphere not previously available on a global scale. Data over an extended period beginning in January 1997 will be presented.

  1. Golden Eagle fatalities and the continental-scale consequences of local wind-energy generation.

    Science.gov (United States)

    Katzner, Todd E; Nelson, David M; Braham, Melissa A; Doyle, Jacqueline M; Fernandez, Nadia B; Duerr, Adam E; Bloom, Peter H; Fitzpatrick, Matthew C; Miller, Tricia A; Culver, Renee C E; Braswell, Loan; DeWoody, J Andrew

    2017-04-01

    Renewable energy production is expanding rapidly despite mostly unknown environmental effects on wildlife and habitats. We used genetic and stable isotope data collected from Golden Eagles (Aquila chrysaetos) killed at the Altamont Pass Wind Resource Area (APWRA) in California in demographic models to test hypotheses about the geographic extent and demographic consequences of fatalities caused by renewable energy facilities. Geospatial analyses of δ(2) H values obtained from feathers showed that ≥25% of these APWRA-killed eagles were recent immigrants to the population, most from long distances away (>100 km). Data from nuclear genes indicated this subset of immigrant eagles was genetically similar to birds identified as locals from the δ(2) H data. Demographic models implied that in the face of this mortality, the apparent stability of the local Golden Eagle population was maintained by continental-scale immigration. These analyses demonstrate that ecosystem management decisions concerning the effects of local-scale renewable energy can have continental-scale consequences.

  2. Golden Eagle fatalities and the continental-scale consequences of local wind-energy generation

    Science.gov (United States)

    Katzner, Todd E.; Nelson, David M.; Braham, Melissa; Doyle, Jacqueline M.; Fernandez, Nadia B.; Duerr, Adam E.; Bloom, Peter H.; Fitzpatrick, Matthew C.; Miller, Tricia A.; Culver, Renee C. E.; Braswell, Loan; DeWoody, J. Andrew

    2017-01-01

    Renewable energy production is expanding rapidly despite mostly unknown environmental effects on wildlife and habitats. We used genetic and stable isotope data collected from Golden Eagles (Aquila chrysaetos) killed at the Altamont Pass Wind Resource Area (APWRA) in California in demographic models to test hypotheses about the geographic extent and demographic consequences of fatalities caused by renewable energy facilities. Geospatial analyses of δ2H values obtained from feathers showed that ≥25% of these APWRA-killed eagles were recent immigrants to the population, most from long distances away (>100 km). Data from nuclear genes indicated this subset of immigrant eagles was genetically similar to birds identified as locals from the δ2H data. Demographic models implied that in the face of this mortality, the apparent stability of the local Golden Eagle population was maintained by continental-scale immigration. These analyses demonstrate that ecosystem management decisions concerning the effects of local-scale renewable energy can have continental-scale consequences.

  3. Impact of Wind Speed Correlation on the Operation of Energy Storage Systems

    Directory of Open Access Journals (Sweden)

    Davril Mathieu

    2016-01-01

    Full Text Available Renewable resources technologies such as wind power currently demonstrate a worldwide popularity thanks to their environmental friendly status and their economic potential. The variability of the wind power output implies the use of practical solutions such as energy storage systems in order to retain the power system stability and reliability. The wind geographical correlation between different wind farms also impacts the system reliability. This paper studies the effects of the wind speed correlation level on the performance of the associated energy storage system (ESS. Wind correlated model using Weibull probability distribution and Nataf transformation is presented. Energy storage system model and energy management algorithm are developed. Both are applied to a modified IEEE-RTS power generation and load model. The case simulation results indicate that the wind speed correlation level between two wind farms impacts the power distribution inside energy storages and that it needs to be considered in order not to overestimate ESS benefits on the system.

  4. A Semi-active Control System for Wind Turbines

    DEFF Research Database (Denmark)

    Caterino, N.; Georgakis, Christos T.; Trinchillo, F.

    2014-01-01

    A semi-active (SA) control system based on the use of smart magnetorheological (MR) dampers to control the structural response of a wind turbine is proposed herein. The innovative approach is based on the implementation and use of a variable-properties base restraint. This is able to modify in real......, and a control algorithm that instantaneously commands the latter during the motion, making them to modulate the reactive force as needed to achieve the performance goals. The design and operation of such a system are shown with reference to a case study consisting of an almost 100 m tall wind turbine, realized...... time its mechanical properties according to the instantaneous decision of a given control logic, the latter addressed to control one or more structural response parameters. The smart base restraint is thought to be a combination of a smooth hinge, elastic springs, large-scale adjustable MR dampers...

  5. A global condition monitoring system for wind turbines

    DEFF Research Database (Denmark)

    Schlechtingen, Meik

    , which bear the potential to support plant owners reducing turbine downtime and lowering costs. In this research a global condition monitoring system is proposed, which provides a platform to take advantage of the different information sources available to operators. One of the most common sources...... the output signal is entirely reconstructed by using other correlated signals. Benefits in fault visibility and lead-time to failure estimatesare observed. A very important signal to monitor contained in the SCADA data is the wind turbine power output. The power output has a direct influence on the revenue...... with false brinelling. Finally, a global fuzzy expert system is developed giving the possibility of linking all available information in terms of fuzzy logic rules. It is important to highlight that this research is based on real measured data coming from two wind power plants with turbines of a different...

  6. Dynamic behaviour of a wind turbine gear system with uncertainties

    Science.gov (United States)

    Beyaoui, Moez; Tounsi, Manel; Abboudi, Kamel; Feki, Nabih; Walha, Lassaad; Haddar, Mohamed

    2016-06-01

    In this paper, a new methodology for taking into account uncertainties in a gearbox transmission system of a horizontal-axis wind turbine is proposed. Gearbox transmission is the major part of the wind turbine's drive train. For a more reasonable evaluation of its dynamic behaviour, the influence of the uncertain parameters should be taken into consideration. The dynamic equations are solved by using the Polynomial Chaos method combined with the ODE45 solver of Matlab. The effects of the random perturbation caused by the aerodynamic torque excitation on the dynamic response of the studied system are discussed in detail. The proposed method is an efficient probabilistic tool for uncertainty propagation. For more accuracy, the Polynomial Chaos results are compared with direct simulations.

  7. SIGNAL : Water vapour flux variability and local wind field investigations within five differently managed agroforestry sites across Germany

    Science.gov (United States)

    Markwitz, Christian; Siebicke, Lukas; Knohl, Alexander

    2016-04-01

    Optimising soil water uptake and ground water consumption in mono-specific agricultural systems plays an important role for sustainable land management. By including tree alleys into the agricultural landscape, called agroforestry (AF), the wind flow is modified leading to a presumably favourable microclimate behind the tree alleys. We expect that this zone is characterized by increased air temperature and atmospheric water vapour content, compared to mono-specific fields. This would extend the growing season and increase the yield production behind the tree alleys. Within the SIGNAL (Sustainable Intensification of Agriculture through Agroforestry) project the evapotranspiration (ET) variability and the local wind field of agroforestry sites compared to mono-specific agricultural systems is investigated. Our study is based on the comparison of five differently managed agroforestry sites across Germany. All site feature one agroforestry plot and one reference plot, which represents a mono-specific cropped system. Each plot is equipped with an eddy-covariance tower, including a high frequency 3D SONIC anemometer and instruments gathering standard meteorological parameter as pressure, temperature, relative humidity, precipitation, ground heat flux, net- and global radiation. The Surface Energy Budget (SEB) method will be used to calculate evapotranspiration QE as QE = - QN - QH - QG - Res by measuring the sensible heat flux, QH, with the eddy covariance method, the radiation balance, QN and the ground heat flux, QG. QH and QN will be measured continuously long-term. We will quantify site specific energy balance non-closure, Res, by temporarily measuring QE, using eddy covariance and a roving tower and then solving the SEB equation for Res. The short term Res will be used to then continuously derive QE from the SEB method. We will compare measured evapotranspiration rates from the SEB method to modelled evapotranspiration of the agroforestry systems through upscaling

  8. Evaluation of different operational strategies for lithium ion battery systems connected to a wind turbine for primary frequency regulation and wind power forecast accuracy improvement

    DEFF Research Database (Denmark)

    Swierczynski, Maciej Jozef; Stroe, Daniel Ioan; Stan, Ana-Irina

    2012-01-01

    High penetration levels of variable wind energy sources can cause problems with their grid integration. Energy storage systems connected to wind turbine/wind power plants can improve predictability of the wind power production and provide ancillary services to the grid. This paper investigates ec...

  9. Coordinated control of wind generation and energy storage for power system frequency regulation

    Science.gov (United States)

    Baone, Chaitanya Ashok

    Large-scale centralized synchronous generators have long been the primary actors in exercising active power and frequency control, and much of the existing grid control framework is predicated upon their dynamic terminal characteristics. Important among these characteristics is the inertia of such generators. These play key roles in determining the electromechanical stability of the electric power grid. Modern wind generator systems are partially or fully connected to the grid through power electronic interfaces, and hence do not present the same level of inertial coupling. The absence of inertial frequency response from modern wind generator systems is a topic of growing concern in power engineering practice, as the penetration of wind generation is expected to grow dramatically in the next few years. Solutions proposed in the literature have sought to address this problem by seeking to mimic the inherent inertial response characteristics of traditional synchronous generators via control loops added to wind generators. Recent literature has raised concerns regarding this approach, and the work here will further examine its shortcomings, motivating approaches that seek to optimally design for the characteristics of the equipment exercising the control, rather than forcing new technologies to mimic the characteristics of synchronous machines. In particular, this work will develop a new approach to power system frequency regulation, with features suited to distributed energy storage devices such as grid-scale batteries and wind turbine speed and blade pitch control. The dynamic characteristics of these new technologies are treated along with existing mechanisms, such as synchronous machine governor control, to develop a comprehensive multi-input control design approach. To make the method practically feasible for geographically distributed power systems, an observer-based distributed control design utilizing phasor measurement unit (PMU) signals along with local

  10. A proposed national wind power R and D program. [offshore wind power system for electric energy supplies

    Science.gov (United States)

    Heronemus, W.

    1973-01-01

    An offshore wind power system is described that consists of wind driven electrical dc generators mounted on floating towers in offshore waters. The output from the generators supplies underwater electrolyzer stations in which water is converted into hydrogen and oxygen. The hydrogen is piped to shore for conversion to electricity in fuel cell stations. It is estimated that this system can produce 159 x 10 to the ninth power kilowatt-hours per year. It is concluded that solar energy - and that includes wind energy - is the only way out of the US energy dilemma in the not too distant future.

  11. Study on characteristics of chirp about Doppler wind lidar system

    Science.gov (United States)

    Du, Li-fang; Yang, Guo-tao; Wang, Ji-hong; Yue, Chuan; Chen, Lin-xiang

    2016-11-01

    In the doppler wind lidar, usually every 4MHz frequency error will produce wind error of 1m/s of 532nm laser. In the Doppler lidar system, frequency stabilization was achieved through absorption of iodine molecules. Commands that control the instrumental system were based on the PID algorithm and coded using VB language. The frequency of the seed laser was locked to iodine molecular absorption line 1109 which is close to the upper edge of the absorption range, with long-time (>4h) frequency-locking accuracy being≤0.5MHz and long-time frequency stability being 10-9 . The experimental result indicated that the seed frequency and the pulse laser frequency have a deviation, which effect is called the laser chirp characteristics. Finally chirp test system was constructed and tested the frequency offset in time. And such frequency deviation is known as Chirp of the laser pulse. The real-time measured frequency difference of the continuous and pulsed lights was about 10MHz, long-time stability deviation was around 5MHz. After experimental testing technology mature, which can monitoring the signal at long-term with corrected the wind speed.

  12. Local food systems: a sustainability review

    OpenAIRE

    Kwong, Edwin

    2011-01-01

    The evolution of global food systems has led to industrial food production processes that have environmental and social external costs. Consumer awareness about sustainability issues brings a heightened awareness of general consumption impacts in our food choices. This paper explores sustainability factors within local food systems in order to understand the impact on sustainability issues within the local food economy. A review of environmental, economic, and social issues within a sustai...

  13. Coastal-Trapped wave by local wind on Todos Santos Bay

    Science.gov (United States)

    Mateos, E.

    2016-12-01

    A numerical study, forced with summer wind, found that the BTS circulation is characterized by two systems: one at the exterior with a strong southward flow that enters to the bay but limited by the 35 m isobath and the other at the rest of the bay. The circulation, in the interior, oscillates between two spatial structures: one in which the general circulation is anticyclonic for two-three days overall the bay, producing a large eddy and a small cyclonic eddy in front of Ensenada's port. Then the anticyclonic eddy evolves to produce the second spatial structure by splitting into two counter rotating eddies making the original anticyclonic to be limited to the northern side of the bay and last three-four days and the small cyclonic eddy reverses its circulation. A study from velocity measurements, found amplification and attenuation of the mean flow with a three-day period in agreement with Mateos et al. (2009). Sea level, temperature and velocities fields, from numerical model, were analyzed to study the generation of coastal-trapped wave on Todos Santos Bay, Mexico. The model included the California Current System and synoptic winds, which are mainly towards the equator. The wind causes a net Southward water transport. In consequence, a bulge of water is formed at the south of the bay and the three-dimensional temperature structure shows a vertical homogeneous upper part of the water column (< 6 m) with a latitudinal gradient. This bulge of water is released every four to five days, as an internal coastal-trapped wave, and the vertical stratification becomes stronger. This coastal-trapped wave explains the current variability with period of three-five days reported in previous studies.

  14. Wind Farms in Rural Areas: How Far Do Community Benefits from Wind Farms Represent a Local Economic Development Opportunity?

    Science.gov (United States)

    Munday, Max; Bristow, Gill; Cowell, Richard

    2011-01-01

    Although the large-scale deployment of renewable technologies can bring significant, localised economic and environmental changes, there has been remarkably little empirical investigation of the rural development implications. This paper seeks to redress this through an analysis of the economic development opportunities surrounding wind energy…

  15. Wind Farms in Rural Areas: How Far Do Community Benefits from Wind Farms Represent a Local Economic Development Opportunity?

    Science.gov (United States)

    Munday, Max; Bristow, Gill; Cowell, Richard

    2011-01-01

    Although the large-scale deployment of renewable technologies can bring significant, localised economic and environmental changes, there has been remarkably little empirical investigation of the rural development implications. This paper seeks to redress this through an analysis of the economic development opportunities surrounding wind energy…

  16. CRES` wind-diesel hybrid system: system identification and performance testing

    Energy Technology Data Exchange (ETDEWEB)

    Vionis, P.S.; Fragoulis, A.N.; Ladakakos, P.D. [Center for Renewable Energy Sources (C.R.E.S.), Pikermi (Greece)

    1996-12-31

    A Wind-Diesel hybrid system has been developed at CRES for investigating the parallel operation of Wind Turbines and Diesel Generators into Autonomous Weak Grids. The system`s architecture is flexible enough so that it can be effectively used for optimising the integration of renewable energy sources in such autonomous power systems, while ensuring the successful implementation of innovative control strategies and testing of new design concepts. In this paper, the design of the wind-diesel simulator and its basic operation modes are described. Results of the components identification procedure are presented. The relevant analysis reveals the components` characteristics under various modes of operation along with the subsystem`s operation limits. The methodology set up for system testing and evaluation has been verified. Results of the first performance tests of the Wind-Diesel hybrid system showing its capabilities are presented and discussed. (Author)

  17. Wind energy system time-domain (WEST) analyzers

    Science.gov (United States)

    Dreier, M. E.; Hoffman, J. A.

    1981-01-01

    A portable analyzer which simulates in real time the complex nonlinear dynamics of horizontal axis wind energy systems was constructed. Math models for an aeroelastic rotor featuring nonlinear aerodynamic and inertial terms were implemented with high speed digital controllers and analog calculation. This model was combined with other math models of elastic supports, control systems, a power train and gimballed rotor kinematics. A stroboscopic display system graphically depicting distributed blade loads, motion, and other aerodynamic functions on a cathode ray tube is included. Limited correlation efforts showed good comparison between the results of this analyzer and other sophisticated digital simulations. The digital simulation results were successfully correlated with test data.

  18. A Meteorological Information Mining-Based Wind Speed Model for Adequacy Assessment of Power Systems With Wind Power

    DEFF Research Database (Denmark)

    Guo, Yifei; Gao, Houlei; Wu, Qiuwei

    2017-01-01

    factors are calculated. Secondly, the meteorological data are classified into several states using an improved Fuzzy C-means (FCM) algorithm. Then the Markov chain is used to model the chronological characteristics of meteorological states and wind speed. The proposed model was proved to be more accurate......Accurate wind speed simulation is an essential prerequisite to analyze the power systems with wind power. A wind speed model considering meteorological conditions and seasonal variations is proposed in this paper. Firstly, using the path analysis method, the influence weights of meteorological...... in capturing the characteristics of probability distribution, auto-correlation and seasonal variations of wind speed compared with the traditional Markov chain Monte Carlo (MCMC) and autoregressive moving average (ARMA) model. Furthermore, the proposed model was applied to adequacy assessment of generation...

  19. Simulation of Variable Speed Wind Generation System Using Boost Converter of Permanent Magnet Synchronous Generator

    Science.gov (United States)

    Ohyama, Kazuhiro; Sakamoto, Tsuyoshi; Arinaga, Shinji; Yamashita, Yukio

    This paper proposes variable-speed wind generation system using the boost converter. The proposed system has three speed control modes for the wind velocity. The control mode of low wind velocity regulates the armature current of the generator with the boost converter to control the speed of wind turbine. The control mode of middle wind velocity regulates the DC link voltage with the vector controlled inverter to control the speed of wind turbine. The control mode of high wind velocity regulates the pitch angle of the wind turbine with the pitch angle control system to control the speed of wind turbine. The hybrid of three control modes extends the variable-speed range. The proposed system simplifies the maintenance and improves the reliability and reduces the cost in compare with the variable-speed wind generation system using PWM converter. This paper describes the control strategy and modeling for simulation using Matlab Simulink of the proposed system. Also this paper describes the control strategy and modeling of variable-speed wind generation system using PWM converter. The steady state and transient responses for wind velocity changes are simulated using the Matlab Simulink. This paper verifies the fundamental performance of the system using boost converter by discussing the simulation results of the both systems.

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

    Science.gov (United States)

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

    2014-05-01

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

  1. Induction generator-induction motor wind-powered pumping system

    Energy Technology Data Exchange (ETDEWEB)

    Miranda, M.S.; Lyra, R.O.C.; Silva, S.R. [CPDEE - UFMG, Belo Horizonte (Brazil)

    1997-12-31

    The energy storage matter plays an important role in wind-electric conversion systems for isolated applications. Having that in mind, two different approaches can be basically considered: either the immediate conversion of the generated electric energy, as in a water pumping system or electric energy storage for later use, as in a battery charging system. Due to some features such as no need of an external reactive power source and, sometimes, a gearbox, permanent-magnet synchronous generators have been broadly used in low rated power isolated systems. Despite that, system performance can be affected when the generator is feeding an inductive load (e.g., an induction motor) under variable-speed-variable-frequency operational conditions. Since there is no effective flux control, motor overload may occur at high wind speeds. Thus, good system performance can be obtained through additional control devices which may increase system cost. Although being rugged and cheap, induction machines always work as a reactive power drain; therefore, they demand an external reactive power source. Considering that, reactive static compensators appear as an attractive alternative to the cost x performance problem. In addition to that, different control strategies can be used so that system performance can be improved.

  2. Wind energy and power system operations: a review of wind integration studies to date

    Energy Technology Data Exchange (ETDEWEB)

    Cesaro, Jennifer de; Porter, Kevin; Milligan, Michael

    2009-12-15

    Wind integration will not be accomplished successfully by doing ''more of the same.'' It will require significant changes in grid planning and operations, continued technical evolution in the design and operation of wind turbines, further adoption and implementation of wind forecasting in the control room, and incorporation of market and policy initiatives to encourage more flexible generation. (author)

  3. Summary of atmospheric wind design criteria for wind energy conversion system development

    Science.gov (United States)

    Frost, W.; Turner, R. E.

    1979-01-01

    Basic design values are presented of significant wind criteria, in graphical format, for use in the design and development of wind turbine generators for energy research. It is a condensed version of portions of the Engineering Handbook on the Atmospheric Environmental Guidelines for Use in Wind Turbine Generator Development.

  4. Optimization of wind-marine hybrid power system configuration based on genetic algorithm

    Science.gov (United States)

    Shi, Hongda; Li, Linna; Zhao, Chenyu

    2017-08-01

    Multi-energy power systems can use energy generated from various sources to improve power generation reliability. This paper presents a cost-power generation model of a wind-tide-wave energy hybrid power system for use on a remote island, where the configuration is optimized using a genetic algorithm. A mixed integer programming model is used and a novel object function, including cost and power generation, is proposed to solve the boundary problem caused by existence of two goals. Using this model, the final optimized result is found to have a good fit with local resources.

  5. Economic evaluation of small wind turbines and hybrid systems for residential use

    Directory of Open Access Journals (Sweden)

    Predescu Mihail

    2016-01-01

    Full Text Available Renewable electricity generating systems are gaining ground in residential sector for the purpose of diminishing the electricity bills or to reaching some degree of energy independence. The decision to invest in small wind turbines or hybrid energy generation technologies should be based on an economic estimation of money invested in such systems. Levelized Cost of Energy (LCOE calculation for local technologies of choice for residential energy generation is a very meaningful figure for deciding whether the investment can bring financial satisfaction and for selecting which type of technology is the best suited for a specific location.

  6. Wind Powering America Podcasts, Wind Powering America (WPA)

    Energy Technology Data Exchange (ETDEWEB)

    2012-04-01

    Wind Powering America and the National Association of Farm Broadcasters produce a series of radio interviews featuring experts discussing wind energy topics. The interviews are aimed at a rural stakeholder audience and are available as podcasts. On the Wind Powering America website, you can access past interviews on topics such as: Keys to Local Wind Energy Development Success, What to Know about Installing a Wind Energy System on Your Farm, and Wind Energy Development Can Revitalize Rural America. This postcard is a marketing piece that stakeholders can provide to interested parties; it will guide them to this online resource for podcast episodes.

  7. Economic and cost engineering aspects of wind energy conversion systems

    Energy Technology Data Exchange (ETDEWEB)

    MacRae, A.N.

    1990-08-01

    A comprehensive analysis of the economic feasibility of current wind energy conversion systems (WECS) from a cost engineering basis is presented. The initial stage covers a subjective review of the cost implications of various design aspects of current medium sized Horizontal Axis Wind Turbines (HAWTs), based around a 330 kW wind turbine (WT). The second stage is focused on the collection and initial analysis of a comprehensive database of WT technical, cost and performance information from over 100 WT models ranging in size from 8 metre to 55 metre rotor diameter. The formulation of a life cycle cost estimation model for HAWTs, based on semi-empirical relationships between sub-system cost, mass and design parameters is described. The economic feasibility of WECS private generating operation under the tariff structures available in the UK, under the auspices of the Energy Act of 1983, is examined, and broad results are given in terms of feasible tariff scenarios for topographical and regional locations throughout the UK. The prospects for reducing the cost of energy from WECS are explored, and the macro-economic and socio-environmental aspects of WECS are examined. (author).

  8. Scalar Controlled Boost PWM Rectifier for Micro Wind Energy Systems

    Directory of Open Access Journals (Sweden)

    J. Chelladurai

    2015-05-01

    Full Text Available Uses of Permanent Magnet Synchronous Generators (PMSG are increasing in variable speed micro-Wind Energy Conversion Systems (WECS. In stand-alone or grid-connected Micro-WECS, extraction of maximum power is vital. To extract maximum power output and to obtain a constant DC bus voltage from variable magnitude and variable frequency voltage output of PMSG and generally a two stage scheme namely i conventional diode bridge rectifier and ii DC-DC Boost/Buck/Buck-Boost converters are used. In this study, a single stage Scalar Controlled PWM (SCPWM Boost Rectifier is proposed in order to minimize the current harmonics and to improve the power factor on source side. The modeling and simulation of PMSG based wind generator and SCPWM Boost rectifier was developed in MATLAB. The harmonic content in the input current waveform of the proposed SCPWM rectifier is compared with the conventional three-phase bridge rectifier. The Simulation results show the effectiveness of the PWM Boost rectifier in terms of effective utilization of source, improved efficiency and harmonic mitigation for PMSG based Wind Generator. Simulation results demonstrate the effectiveness of the proposed system in reducing the current and voltage THD on source side.

  9. Crowbar system in doubly fed induction wind generators

    Energy Technology Data Exchange (ETDEWEB)

    Salles, M. B. C.; Cardoso, J. R. [Laboratory of Applied Electromagnetism-LMAG, University of Sao Paulo (Brazil); Hameyer, K. [Institute of Electrical Machines-IEM, RWTH Aachen University (Germany); Grilo, A. P. [Engineering, Modeling and Applied Social Science Center-Federal University of ABC, Santo Andre (Brazil); Rahmann, C. [Institute of Power Systems and Power Economics-IAEW, RWTH Aachen University (Germany)

    2010-07-01

    In the last 15 years, the use of doubly fed induction machines in modern variable-speed wind turbines has increased rapidly. This development has been driven by the cost reduction as well as the low-loss generation of Insulated Gate Bipolar Transistors (IGBT). According to new grid code requirements, wind turbines must remain connected to the grid during grid disturbances. Moreover, they must also contribute to voltage support during and after grid faults. The crowbar system is essential to avoid the disconnection of the doubly fed induction wind generators from the network during faults. The insertion of the crowbar in the rotor circuits for a short period of time enables a more efficient terminal voltage control. As a general rule, the activation and the deactivation of the crowbar system is based only on the DC-link voltage level of the back-to-back converters. In this context, the authors discuss the critical rotor speed to analyze the instability of doubly fed induction generators during grid faults. (author)

  10. Grid connection of active stall wind farms using a VSC based DC transmission system

    DEFF Research Database (Denmark)

    Iov, Florin; Sorensen, Paul; Hansen, Anca-Daniela;

    2005-01-01

    are fulfilled. However, the traditional squirrel-cage generators based wind turbines/wind farms directly connected to the grid have less control capabilities. These wind turbines/farms cannot regulate their production and contribute to power system stability. A DC transmission system for connection...

  11. Proceedings of the third biennial conference and workshop on wind energy conversion systems. Volume I

    Energy Technology Data Exchange (ETDEWEB)

    Kornreich, T R [ed.

    1978-05-01

    Separate abstracts are included for 38 papers presented concerning large scale wind systems, small scale wind systems, regional and economic analysis, wind characteristics research, environmental and institutional considerations, and international activities. Four papers were previously input into the energy data base.

  12. Analysis of off-grid hybrid wind turbine/solar PV water pumping systems

    Science.gov (United States)

    While many remote water pumping systems exist (e.g. mechanical windmills, solar photovoltaic , wind-electric, diesel powered), very few combine both the wind and solar energy resources to possibly improve the reliability and the performance of the system. In this paper, off-grid wind turbine (WT) a...

  13. A Chance-Constrained Economic Dispatch Model in Wind-Thermal-Energy Storage System

    Directory of Open Access Journals (Sweden)

    Yanzhe Hu

    2017-03-01

    Full Text Available As a type of renewable energy, wind energy is integrated into the power system with more and more penetration levels. It is challenging for the power system operators (PSOs to cope with the uncertainty and variation of the wind power and its forecasts. A chance-constrained economic dispatch (ED model for the wind-thermal-energy storage system (WTESS is developed in this paper. An optimization model with the wind power and the energy storage system (ESS is first established with the consideration of both the economic benefits of the system and less wind curtailments. The original wind power generation is processed by the ESS to obtain the final wind power output generation (FWPG. A Gaussian mixture model (GMM distribution is adopted to characterize the probabilistic and cumulative distribution functions with an analytical expression. Then, a chance-constrained ED model integrated by the wind-energy storage system (W-ESS is developed by considering both the overestimation costs and the underestimation costs of the system and solved by the sequential linear programming method. Numerical simulation results using the wind power data in four wind farms are performed on the developed ED model with the IEEE 30-bus system. It is verified that the developed ED model is effective to integrate the uncertain and variable wind power. The GMM distribution could accurately fit the actual distribution of the final wind power output, and the ESS could help effectively decrease the operation costs.

  14. Globalization and localization of Management Control Systems

    DEFF Research Database (Denmark)

    Toldbod, Thomas; Israelsen, Poul

    2014-01-01

    have more particular characteristics. Specifically, this study finds that cybernetic controls and administrative controls are designed as global management control systems. Planning controls are glocal systems and reward & compensation controls assume local characteristics. The finding leads......Through an empirical case study this article examines the operation of multiple management control systems as a package in a Danish manufacturing company. The analysis focuses on four different management control systems; cybernetic controls, planning controls, reward controls, and administrative...... controls, through the theoretical lens of globalization, localization, and glocalization. The analysis documents that these different management control systems are affected differently by the processes of globalization and localization, whereby some are universal throughout the organization and others...

  15. Laser Doppler velocimetry applied to the measurement of local and global wind

    Energy Technology Data Exchange (ETDEWEB)

    Vaughan, J.M.; Forrester, P.A. (Royal Signals and Radar Establishment, Malvern (GB))

    1989-01-01

    The analysis of radiation scattered from naturally occurring aerosols carried along by the wind provides a powerful tool for the study of wind structure and enables the air flow to be studied from a single, non-perturbing, measuring station. In this paper, we outline the current status of wind measurement from ground-based, air borne and space platforms. The potential for using Laser Doppler Velocimetry on a range of applications with wind turbine generators is discussed. (author).

  16. ANEMOS: Development of a next generation wind power forecasting system for the large-scale integration of onshore and offshore wind farms.

    Science.gov (United States)

    Kariniotakis, G.; Anemos Team

    2003-04-01

    offshore wind farms taking into account advances in marine meteorology (interaction between wind and waves, coastal effects). The benefits from the use of satellite radar images for modeling local weather patterns are investigated. A next generation forecasting software, ANEMOS, will be developed to integrate the various models. The tool is enhanced by advanced Information Communication Technology (ICT) functionality and can operate both in stand alone, or remote mode, or be interfaced with standard Energy or Distribution Management Systems (EMS/DMS) systems. Contribution: The project provides an advanced technology for wind resource forecasting applicable in a large scale: at a single wind farm, regional or national level and for both interconnected and island systems. A major milestone is the on-line operation of the developed software by the participating utilities for onshore and offshore wind farms and the demonstration of the economic benefits. The outcome of the ANEMOS project will help consistently the increase of wind integration in two levels; in an operational level due to better management of wind farms, but also, it will contribute to increasing the installed capacity of wind farms. This is because accurate prediction of the resource reduces the risk of wind farm developers, who are then more willing to undertake new wind farm installations especially in a liberalized electricity market environment.

  17. Power Electronics Control of Wind Energy in Distributed Power System

    DEFF Research Database (Denmark)

    Iov, Florin; Ciobotaru, Mihai; Blaabjerg, Frede

    2008-01-01

    is to change the electrical power production sources from the conventional, fossil (and short term) based energy sources to renewable energy resources. The other is to use high efficient power electronics in power generation, power transmission/distribution and end-user application. This paper discuss the most...... emerging renewable energy sources, wind energy, which by means of power electronics are changing from being a minor energy source to be acting as an important power source in the energy system. Power electronics is the enabling technology and the presentation will cover the development in wind turbine...... technology from kW to MW, discuss which power electronic solutions are most feasible and used today....

  18. Vibration-based SHM System: Application to Wind Turbine Blades

    DEFF Research Database (Denmark)

    Tcherniak, D.; Mølgaard, Lasse Lohilahti

    2015-01-01

    This study presents an vibration-based system designed for structural health monitoring of wind turbine blades. Mechanical energy is introduced by means of an electromechanical actuator mounted inside the blade. The actuator's plunger periodically hits the blade structure; the induced vibrations...... propagate along the blade and are measured by an array of accelerometers. Unsupervised learning is applied to the data: the vibration patterns corresponding to the undamaged blade are used to create a statistical model of the reference state. During the detection stage, the current vibration pattern...... is compared with the reference state, and the novelties can be associated with damage. The vibration pattern is described by the covariance matrix between the accelerometer signals. The mid-range frequencies are used: this range is above the frequencies excited by blade-wind interaction, thus ensuring a good...

  19. Power system integration and control of variable speed wind turbines

    Energy Technology Data Exchange (ETDEWEB)

    Eek, Jarle

    2009-12-15

    A wind power plant is a highly dynamic system that dependent on the type of technology requires a number of automatic control loops. This research deals with modelling, control and analysis related to power system integration of variable speed, pitch controlled wind turbines. All turbine components have been modelled and implemented in the power system simulation program SIMPOW, and a description of the modelling approach for each component is given. The level of model detail relates to the classical modelling of power system components for power system stability studies, where low frequency oscillations are of special importance. The wind turbine model includes a simplified representation of the developed rotor torque and the thrust force based on C{sub p-} and C{sub t} characteristic curves. The mechanical system model represents the fundamental torsional mode and the first mode of blades and tower movements. Two generator technologies have been investigated. The doubly fed induction generator (DFIG) and the stator converter interfaced permanent magnet synchronous generator (PMSG). A simplified model of a 2 level voltage source converter is used for both machine types. The generator converter controllers have been given special attention. All model components are linearized for the purpose of control system design and power system interaction related to small signal stability analysis. Different control strategies discussed in the literature have been investigated with regard to power system interaction aspects. All control parameters are identified using the internal model control approach. The analysis is focused on three main areas: 1. Identification of low damped oscillatory modes. This is carried out by the establishment and discussion of wind turbine modelling. 2. Interaction between control loops. A systematic approach is presented in order to analyse the influence of control loops used in variable speed wind turbines. 3.Impact on power system performance

  20. Power System Modeling of 20% Wind-Generated Electricity by 2030: Preprint

    Energy Technology Data Exchange (ETDEWEB)

    Hand, M.; Blair, N.; Bolinger, M.; Wiser, R.; O' Connell, R.; Hern, T.; Miller, B.

    2008-06-01

    This paper shows the results of the Wind Energy Deployment System model used to estimate the costs and benefits associated with producing 20% of the nation's electricity from wind technology by 2030.

  1. Compressed air energy storage system reservoir size for a wind energy baseload power plant

    Energy Technology Data Exchange (ETDEWEB)

    Cavallo, A.J.

    1996-12-31

    Wind generated electricity can be transformed from an intermittent to a baseload resource using an oversized wind farm in conjunction with a compressed air energy storage (CAES) system. The size of the storage reservoir for the CAES system (solution mined salt cavern or porous media) as a function of the wind speed autocorrelation time (C) has been examined using a Monte Carlo simulation for a wind class 4 (wind power density 450 W m{sup -2} at 50 m hub height) wind regime with a Weibull k factor of 2.5. For values of C typically found for winds over the US Great Plains, the storage reservoir must have a 60 to 80 hour capacity. Since underground reservoirs account for only a small fraction of total system cost, this larger storage reservoir has a negligible effect on the cost of energy from the wind energy baseload system. 7 refs., 2 figs., 1 tab.

  2. A new computational algorithm for the calculation of maximum wind energy penetration in autonomous electrical generation systems

    Energy Technology Data Exchange (ETDEWEB)

    Kaldellis, J.K.; Kavadias, K.A. [Lab of Soft Energy Applications and Environmental Protection, TEI Piraeus, P.O. Box 41046, Athens 12201 (Greece); Filios, A.E. [Fluid Mechanics and Turbomachines Lab., School of Pedagogical and Technological Education, 14121 N. Heraklio Attica (Greece)

    2009-07-15

    The entirety of Aegean Sea Islands, including Crete, is characterized during the last decade by a considerable annual increase of the electrical power demand exceeding the 5% in annual basis. This continuous amplifying electricity consumption is hardly fulfilled by several outmoded internal combustion engines usually at a very high operational cost. On the other hand most of the islands possess high wind potential that may substantially contribute in order to meet the corresponding load demand. However, in this case some wind energy absorption problems related with the collaboration between wind parks and the local electricity production system cannot be neglected. In this context, the present study is devoted to realistically estimating the maximum wind energy absorption in autonomous electrical island networks. For this purpose a new reliable and integrated numerical algorithm is developed, using the available information of the corresponding electricity generation system, in order to calculate the maximum acceptable wind power contribution in the system, under the normal restrictions that the system manager imposes. The proposed algorithm is successfully compared with existing historical data as well as with the results of a recent investigation based almost exclusively on the existing wind park's energy production. (author)

  3. Local construction of small wind turbines : the EOLSenegal Project experience; Vers la construction locale de petits aerogenerateurs : l'experience du projet EOLSenegal

    Energy Technology Data Exchange (ETDEWEB)

    Joulain, C.; Kebe, C.M.F. [Centre International de Formation et de Recherche en Energie Solaire (Senegal); Zambeaux, N. [Agence de l' Environnement et de la Maitrise de l' Energie, Paris (France); Galy, S. [La Fondation Nicola Hulot pour la Nature et l' Homme (France)

    2008-04-15

    The Centre International de Formation et de Recherche en Energie Solaire (CIFRES) is working to set-up a local branch of manufacturers and maintenance staff for small wind turbines destined for producing electricity in Senegal. The EOLSenegal Project stipulates that a minimum of 95 per cent of local materials must be used to manufacture the wind turbines and that all production and maintenance must occur in Senegal. The purpose of the project is to demonstrate the feasibility of rural electrification projects while determining which technology among wind power, solar photovoltaic or biofuel is best suited for contributing to energy independence and the industrial development of the country through job creation. There are multiple applications for wind energy, including domestic lighting; electrification of community buildings; electrification of district housing; pumping for drinking water; the transformation and conservation of agricultural products; driving force for local crafts such as woodworking, metals, sewing, and hairdressing; and, battery recharging for small food appliances. Wind power and solar energy were touted as being the best solution for meeting the electricity needs of rural populations. The first phase of the EOLSenegal Project involves a feasibility study and site selection followed by phase 2 in which the equipment will be installed. The last industrial phase of the project will be based on the experience gained during the first 2 phases with a market study and financial estimate to draw investors. It was concluded that while small wind turbines may solve some of Senegal's electricity needs, they cannot meet the needs alone and should be used in conjunction with other forms of energy such as solar, thermal, biomass or biogas. 4 figs.

  4. Wind-Enhanced Interaction of Radiation and Dust (WEIRD) and the Growth and Maintenance of Local Dust Storms on Mars

    CERN Document Server

    Rafkin, Scot C Randell

    2011-01-01

    A radiative-dynamic positive feedback mechanism (Wind Enhanced Interaction of Radiation and Dust: WEIRD) for localized Mars dust disturbances was previously found to operate in highly idealized numerical experiments. Numerical simulations are used to test for the presence and quantitative effect of the radiative-dynamic WEIRD feedback mechanism under more realistic conditions. Comparisons between cases where lifted dust is radiatively active and radiatively passive elucidate the importance of the dust radiative forcing on the thermodynamic and kinematic structure of the atmosphere. The WEIRD feedback mechanism does operate under realistic conditions, although it can be masked and diminished by a variety of other forcing mechanisms. Globally increased dust loading is found to accelerate the local winds while simultaneously diminishing the impact of local physiographical forcing. Local enhancements of dust produce a thermal and dynamical response that resembles many of the essential features seen in the idealiz...

  5. Digital Control System For Wind-Tunnel Model

    Science.gov (United States)

    Hoadley, Sherwood T.; Mcgraw, Sandra

    1995-01-01

    Multiple functions performed by multiple coordinated processors for real-time control. Multiple input, multiple-output, multiple-function digital control system developed for wind-tunnel model of advanced fighter airplane with actively controlled flexible wings. Digital control system provides flexibility in selection of control laws, sensors, and actuators, plus some redundancy to accommodate failures in some of its subsystems. Implements feedback control scheme providing simultaneously for suppression of flutter, control of roll angle, roll-rate tracking during maximized roll maneuvers, and alleviation of loads during roll maneuvers.

  6. Environmentally-adapted local energy systems

    Energy Technology Data Exchange (ETDEWEB)

    Moe, N.; Oefverholm, E. [NUTEK, Stockholm (Sweden); Andersson, Owe [EKAN Gruppen (Sweden); Froste, H. [Swedish Environmental Protection Agency, Stockholm (Sweden)

    1997-10-01

    Energy companies, municipalities, property companies, firms of consultants, environmental groups and individuals are examples of players working locally to shape environmentally adapted energy systems. These players have needed information making them better able to make decisions on cost-efficient, environmentally-adapted energy systems. This book answers many of the questions they have put. The volume is mainly based on Swedish handbooks produced by the Swedish National Board for Industrial and Technical Development, NUTEK, together with the Swedish Environmental Protection Agency. These handbooks have been used in conjunction with municipal energy planning, local Agenda 21 work, to provide a basis for deciding on concrete local energy systems. The contents in brief: -The book throws new light on the concept of energy efficiency; -A section on the environment compares how air-polluting emissions vary with different methods of energy production; -A section contains more than 40 ideas for measures which can be profitable, reduce energy consumption and the impact on the environment all at the same time; -The book gives concrete examples of new, alternative and environmentally-adapted local energy systems. More efficient use of energy is included as a possible change of energy system; -The greatest emphasis is laid upon alternative energy systems for heating. It may be heating in a house, block of flats, office building or school; -Finally, there are examples of environmentally-adapted local energy planning.

  7. Advanced design of local ventilation systems

    Energy Technology Data Exchange (ETDEWEB)

    Kulmala, I. [VTT Manufacturing Technology, Espoo (Finland). Safety Technology

    1997-12-31

    Local ventilation is widely used in industry for controlling airborne contaminants. However, the present design practices of local ventilation systems are mainly based on empirical equations and do not take quantitatively into account the various factors affecting the performance of these systems. The aim of this study was to determine the applicability and limitations of more advanced fluid mechanical methods to the design and development of local ventilation systems. The most important factors affecting the performance of local ventilation systems were determined and their effect was studied in a systematic manner. The numerical calculations were made with the FLUENT computer code and they were verified by laboratory experiments, previous measurements or analytical solutions. The results proved that the numerical calculations can provide a realistic simulation of exhaust openings, effects of ambient air flows and wake regions. The experiences with the low-velocity local supply air showed that these systems can also be modelled fairly well. The results were used to improve the efficiency and thermal comfort of a local ventilation unit and to increase the effective control range of exhaust hoods. In the simulation of the interaction of a hot buoyant source and local exhaust, the predicted capture efficiencies were clearly higher than those observed experimentally. The deviations between measurements and non-isothermal flow calculations may have partly been caused by the inability to achieve grid independent solutions. CFD simulations is an advanced and flexible tool for designing and developing local ventilation. The simulations can provide insight into the time-averaged flow field which may assist us in understanding the observed phenomena and to explain experimental results. However, for successful calculations the applicability and limitations of the models must be known. (orig.) 78 refs.

  8. Estimation of Local Scour around Wind Turbine's Base of Offshore Wind Farm%近海风电场风机基础局部冲刷估算

    Institute of Scientific and Technical Information of China (English)

    王卫远; 李睿元; 杨娟; 何倩倩

    2012-01-01

    建设近海风电场时,风机所处的海洋环境十分复杂,在复杂的气象水文条件影响下,风机基础周围会出现冲刷坑,进而影响风机基础的稳定.所以,风机基础的局部冲刷深度是工程设计的重要参数.采用埕岛油田海洋平台基础局部冲刷现场观测资料,对国内常用的两个计算基础局部冲刷深度的经验公式(韩海骞公式和王汝凯公式)进行验证,发现该海域波浪对泥沙的作用不可忽略.运用波流合成速度代替纯潮流速度,改进的韩海骞公式计算结果与实测值吻合良好.最后,对与埕岛油田海域环境相似的拟建的风电场工程风机基础的局部冲刷深度进行了计算,计算结果对实际工程具有一定的参考价值.%When building the offshore wind farm, the wind turbine's marine environment is very complex. Seour hole around wind turbine's base will form because of complex meieorology and hydrology factors' influence. Thereby, il will affect the stability of wind turbine's base. So, the local scour depth of wind turbine is an important parameter for engineering design. We use the field observed data of Chengdao oil field's pile to test domestic two commonly used empirical formulas (HAN Hai-qian's formula and WANG Ru-kai's formula), and we find that the role of wave on sand can not be ignored in the area. And then, we use the synthesis speed of wave and current instead of the pure tidal current speed, and we can find that the result by the improved HAN Hai-qian's formula is in good agreement with the measured result. At last, we calculate the local scour depth of wind turbine of the proposed wind farm which has a similar marine environment to Chengdao oil field. The results have some reference value to the actual project.

  9. Battery sizing for a stand alone passive wind system using statistical techniques

    OpenAIRE

    Belouda, Malek; Belhadj, Jamel; Sareni, Bruno; Roboam, Xavier

    2011-01-01

    In this paper, an original optimization method to jointly determine a reduced study term and an optimum battery sizing is investigated. This storage device is used to connect a passive wind turbine system with a stand alone network. A Weibull probability density function is used to generate different wind speed data. The passive wind system is composed of a wind turbine, a permanent magnet synchronous generator feeding a diode rectifier associated with a very low voltage DC battery bus. This ...

  10. Building 865 Hypersonic Wind Tunnel Power System Analysis

    Energy Technology Data Exchange (ETDEWEB)

    Schneider, Larry X. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

    2015-02-01

    This report documents the characterization and analysis of a high current power supply for the building 865 Hypersonic Wind Tunnel at Sandia National Laboratories. The system described in this report became operational in 2013, replacing the original 1968 system which employed an induction voltage regulator. This analysis and testing was completed to help the parent organization understand why an updated and redesigned power system was not delivering adequate power to resistive heater elements in the HWT. This analysis led to an improved understanding of the design and operation of the revised 2013 power supply system and identifies several reasons the revised system failed to achieve the performance of the original power supply installation. Design modifications to improve the performance of this system are discussed.

  11. Electric utility application of wind energy conversion systems on the island of Oahu

    Energy Technology Data Exchange (ETDEWEB)

    Lindley, C.A.; Melton, W.C.

    1979-02-23

    This wind energy application study was performed by The Aerospace Corporation for the Wind Systems Branch of the Department of Energy. The objective was to identify integration problems for a Wind Energy Conversion System (WECS) placed into an existing conventional utility system. The integration problems included environmental, institutional and technical aspects as well as economic matters, but the emphasis was on the economics of wind energy. The Hawaiian Electric Company utility system on the island of Oahu was selected for the study because of the very real potential for wind energy on that island, and because of the simplicity afforded in analyzing that isolated utility.

  12. Blowing against the wind-An exploratory application of actor network theory to the analysis of local controversies and participation processes in wind energy

    Energy Technology Data Exchange (ETDEWEB)

    Jolivet, Eric, E-mail: eric.jolivet@iae-toulouse.f [CRM-CNRS Centre for Research in Management, University of Toulouse I Capitole, 2, rue du Doyen Marty, 31 042 Toulouse Cedex 09 (France); Heiskanen, Eva, E-mail: eva.heiskanen@ncrc.f [National Consumer Research Centre and Helsinki School of Economics, P.O. Box, 00531 Helsinki (Finland)

    2010-11-15

    This paper analyses the deployment of wind power and the related local controversies using actor-network theory (ANT). ANT provides conceptual instruments for a fine-tuned analysis of the contingencies that condition a project's success or failure by focusing on the micro-decisions that intertwine the material aspects of the technology, the site where it is implemented, the participation process, and the social relations in which they are embedded. By considering controversies as alternative efforts of competing networks of actors to 'frame' the reality and enroll others, ANT sheds light on the complex and political nature of planning a wind farm project, insofar as it consist in aligning material and human behaviours into a predictable scenario. 'Overflows' occur when actors do not conform to expectations, adopt conflicting positions and develop their own interpretations of the project, thus obliging designers to adapt their frames and change their plans. To demonstrate this framework, we apply it to the case of a wind farm project in the South of France, near Albi. Our analysis suggests a new approach to examining wind power projects in terms of the interaction between globally circulating technologies, unique characteristics of the site, the participation process and the social dynamics that emerge when these are combined.

  13. Blowing against the wind - An exploratory application of actor network theory to the analysis of local controversies and participation processes in wind energy

    Energy Technology Data Exchange (ETDEWEB)

    Jolivet, Eric [CRM-CNRS Centre for Research in Management, University of Toulouse I Capitole, 2, rue du Doyen Marty, 31 042 Toulouse Cedex 09 (France); Heiskanen, Eva [National Consumer Research Centre and Helsinki School of Economics, P.O. Box, 00531 Helsinki (Finland)

    2010-11-15

    This paper analyses the deployment of wind power and the related local controversies using actor-network theory (ANT). ANT provides conceptual instruments for a fine-tuned analysis of the contingencies that condition a project's success or failure by focusing on the micro-decisions that intertwine the material aspects of the technology, the site where it is implemented, the participation process, and the social relations in which they are embedded. By considering controversies as alternative efforts of competing networks of actors to 'frame' the reality and enroll others, ANT sheds light on the complex and political nature of planning a wind farm project, insofar as it consist in aligning material and human behaviours into a predictable scenario. 'Overflows' occur when actors do not conform to expectations, adopt conflicting positions and develop their own interpretations of the project, thus obliging designers to adapt their frames and change their plans. To demonstrate this framework, we apply it to the case of a wind farm project in the South of France, near Albi. Our analysis suggests a new approach to examining wind power projects in terms of the interaction between globally circulating technologies, unique characteristics of the site, the participation process and the social dynamics that emerge when these are combined. (author)

  14. p-systems in local Noether lattices

    Directory of Open Access Journals (Sweden)

    E. W. Johnson

    1994-01-01

    Full Text Available In this paper we introduce the concept of a p-system in a local Noether lattice and obtain several characterizations of these elements. We first obtain a topological characterization and then a characterization in terms of the existence of a certain type of decreasing sequence of elements. In addition, p-systems are characterized in quotient lattices and completions.

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

    DEFF Research Database (Denmark)

    Michalke, Gabriele; Hansen, Anca Daniela

    2010-01-01

    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...... 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....

  16. Analysis of Highly Wind Power Integrated Power System model performance during Critical Weather conditions

    DEFF Research Database (Denmark)

    Basit, Abdul; Hansen, Anca Daniela; Sørensen, Poul Ejnar

    2014-01-01

    . For this purpose, the power system model has been developed that represents the relevant dynamic features of power plants and compensates for power imbalances caused by the forecasting error during critical weather conditions. The regulating power plan, as an input time series for the developed power system model......Secure power system operation of a highly wind power integrated power system is always at risk during critical weather conditions, e.g. in extreme high winds. The risk is even higher when 50% of the total electricity consumption has to be supplied by wind power, as the case for the future Danish...... power system in 2020. This paper analyses and compares the performance of the future Danish power system during extreme wind speeds, where wind power plants are either controlled through a traditional High Wind Shut Down storm controller or a new High Wind Extended Production storm controller...

  17. Stand-alone wind system with Vanadium Redox Battery energy storage

    DEFF Research Database (Denmark)

    Teodorescu, Remus; Barote, L.; Weissbach, R.

    2008-01-01

    Energy storage devices are required for power balance and power quality in stand alone wind energy systems. A Vanadium Redox Flow Battery (VRB) system has many features which make its integration with a stand-alone wind energy system attractive. This paper proposes the integration of a VRB system...... with a typical stand-alone wind energy system during wind speed variation as well as transient performance under variable load. The investigated system consists of a variable speed wind turbine with permanent magnet synchronous generator (PMSG), diode rectifier bridge, buck-boost converter, bidirectional charge...... controller, transformer, inverter, ac loads and VRB (to store a surplus of wind energy and to supply power during a wind power shortage). The main purpose is to supply domestic appliances through a single phase 230V, 50Hz inverter. Simulations are accomplished in order to validate the stability of the supply....

  18. Short term fluctuations of wind and solar power systems

    Science.gov (United States)

    Anvari, M.; Lohmann, G.; Wächter, M.; Milan, P.; Lorenz, E.; Heinemann, D.; Rahimi Tabar, M. Reza; Peinke, Joachim

    2016-06-01

    Wind and solar power are known to be highly influenced by weather events and may ramp up or down abruptly. Such events in the power production influence not only the availability of energy, but also the stability of the entire power grid. By analysing significant amounts of data from several regions around the world with resolutions of seconds to minutes, we provide strong evidence that renewable wind and solar sources exhibit multiple types of variability and nonlinearity in the time scale of seconds and characterise their stochastic properties. In contrast to previous findings, we show that only the jumpy characteristic of renewable sources decreases when increasing the spatial size over which the renewable energies are harvested. Otherwise, the strong non-Gaussian, intermittent behaviour in the cumulative power of the total field survives even for a country-wide distribution of the systems. The strong fluctuating behaviour of renewable wind and solar sources can be well characterised by Kolmogorov-like power spectra and q-exponential probability density functions. Using the estimated potential shape of power time series, we quantify the jumpy or diffusive dynamic of the power. Finally we propose a time delayed feedback technique as a control algorithm to suppress the observed short term non-Gaussian statistics in spatially strong correlated and intermittent renewable sources.

  19. Research Developments on Power System Integration of Wind Power

    DEFF Research Database (Denmark)

    Chen, Zhe; Hansen, Jens Carsten; Qiuwei, Wu

    2011-01-01

    This paper presents an overview on the recent research activities and tendencies regarding grid integration of wind power in Denmark and some related European activities, including power electronics for enhancing wind power controllability, wind turbines and wind farms modeling,wind power...... variability and prediction, wind power plant ancillary services, grid connection and operation, Smart grids and demand side management under market functionality. The topics of the first group of PhD program starting 2011 under the wind energy Sino-Danish Centre for Education & Research (SDC) are also...

  20. Calculation of design load for the MOD-5A 7.3 mW wind turbine system

    Science.gov (United States)

    Mirandy, L.; Strain, J. C.

    1995-01-01

    Design loads are presented for the General Electric MOD-SA wind turbine. The MOD-SA system consists of a 400 ft. diameter, upwind, two-bladed, teetered rotor connected to a 7.3 mW variable-speed generator. Fatigue loads are specified in the form of histograms for the 30 year life of the machine, while limit (or maximum) loads have been derived from transient dynamic analysis at critical operating conditions. Loads prediction was accomplished using state of the art aeroelastic analyses developed at General Electric. Features of the primary predictive tool - the Transient Rotor Analysis Code (TRAC) are described in the paper. Key to the load predictions are the following wind models: (1) yearly mean wind distribution; (2) mean wind variations during operation; (3) number of start/shutdown cycles; (4) spatially large gusts; and (5) spatially small gusts (local turbulence). The methods used to develop statistical distributions from load calculations represent an extension of procedures used in past wind programs and are believed to be a significant contribution to Wind Turbine Generator analysis. Test/theory correlations are presented to demonstrate code load predictive capability and to support the wind models used in the analysis. In addition MOD-5A loads are compared with those of existing machines. The MOD-5A design was performed by the General Electric Company, Advanced Energy Program Department, under Contract DEN3-153 with NASA Lewis Research Center and sponsored by the Department of Energy.

  1. Wind power integration into the automatic generation control of power systems with large-scale wind power

    DEFF Research Database (Denmark)

    Basit, Abdul; Hansen, Anca Daniela; Altin, Müfit

    2014-01-01

    Transmission system operators have an increased interest in the active participation of wind power plants (WPP) in the power balance control of power systems with large wind power penetration. The emphasis in this study is on the integration of WPPs into the automatic generation control (AGC......) of the power system. The present paper proposes a coordinated control strategy for the AGC between combined heat and power plants (CHPs) and WPPs to enhance the security and the reliability of a power system operation in the case of a large wind power penetration. The proposed strategy, described...... and exemplified for the future Danish power system, takes the hour-ahead regulating power plan for generation and power exchange with neighbouring power systems into account. The performance of the proposed strategy for coordinated secondary control is assessed and discussed by means of simulations for different...

  2. Reference Manual for the System Advisor Model's Wind Power Performance Model

    Energy Technology Data Exchange (ETDEWEB)

    Freeman, J.; Jorgenson, J.; Gilman, P.; Ferguson, T.

    2014-08-01

    This manual describes the National Renewable Energy Laboratory's System Advisor Model (SAM) wind power performance model. The model calculates the hourly electrical output of a single wind turbine or of a wind farm. The wind power performance model requires information about the wind resource, wind turbine specifications, wind farm layout (if applicable), and costs. In SAM, the performance model can be coupled to one of the financial models to calculate economic metrics for residential, commercial, or utility-scale wind projects. This manual describes the algorithms used by the wind power performance model, which is available in the SAM user interface and as part of the SAM Simulation Core (SSC) library, and is intended to supplement the user documentation that comes with the software.

  3. Structural analysis of wind turbine rotors for NSF-NASA Mod-0 wind power system

    Science.gov (United States)

    Spera, D. A.

    1976-01-01

    Preliminary estimates are presented of vibratory loads and stresses in hingeless and teetering rotors for the proposed NSF-NASA Mod-0 wind power system. Preliminary blade design utilizes a tapered tubular aluminum spar which supports nonstructural aluminum ribs and skin and is joined to the rotor hub by a steel shank tube. Stresses in the shank of the blade are calculated for static, rated, and overload operating conditions. Blade vibrations were limited to the fundamental flapping modes, which were elastic cantilever bending for hingeless rotor blades and rigid-body rotation for teetering rotor blades. The MOSTAB-C computer code was used to calculate aerodynamic and mechanical loads. The teetering rotor has substantial advantages over the hingeless rotor with respect to shank stresses, fatigue life, and tower loading. The hingeless rotor analyzed does not appear to be structurally stable during overloads.

  4. Hydraulic Motor Driving Variable-Pitch System for Wind Turbine

    Directory of Open Access Journals (Sweden)

    Ye HUANG

    2013-11-01

    Full Text Available The present hydraulic variable-pitch mechanism of wind turbine uses three hydraulic cylinders to drive three crank and connecting rod mechanisms respectively; the blades are moved with the cranks. The hydraulic variable-pitch mechanism has complex structure, occupies a lot of space and its maintenance is trouble. In order to make up for the shortcomings of hydraulic cylinder variable-pitch system, the present hydraulic variable-pitch mechanism should be changed as follows: hydraulic motors are used to drive gears; gears drive blades; the electro-hydraulic proportional valves are used to control hydraulic motors. The hydraulic control part and electrical control part of variable-pitch system is redesigned. The new variable-pitch system is called hydraulic motor driving variable-pitch system. The new variable-pitch system meets the control requirements of blade pitch, makes the structure simple and its application effect is perfect.    

  5. Speed Synchronization of web winding System with Sliding Mode Control

    Directory of Open Access Journals (Sweden)

    Hachemi Glaoui

    2013-02-01

    Full Text Available A continuous web winding system is a large-scale, complex interconnected dynamic system with numerous tension zones to transport the web while processing it. There are two control schemes for large-scale system control: the centralized scheme and the decentralized scheme. Centralized control is the traditional control method, which considers all the information about the system to be a single dynamic model and design a control system for this model. A speed synchronization control strategy for multiple induction motors, based on adjacent cross-coupling control structure, is developed by employing total sliding mode control method. The proposed control strategy is to stabilize speed tracking of each induction motor while synchronizing its speed with the speed of the other motors so as to make speed synchronization error amongst induction motors converge to zero. The global stability and the convergence of the designed controller are proved by using Lyapunov method. Simulation results demonstrate the effectiveness of the proposed method.

  6. Vibration-based SHM System: Application to Wind Turbine Blades

    Science.gov (United States)

    Tcherniak, D.; Mølgaard, L. L.

    2015-07-01

    This study presents an vibration-based system designed for structural health monitoring of wind turbine blades. Mechanical energy is introduced by means of an electromechanical actuator mounted inside the blade. The actuator's plunger periodically hits the blade structure; the induced vibrations propagate along the blade and are measured by an array of accelerometers. Unsupervised learning is applied to the data: the vibration patterns corresponding to the undamaged blade are used to create a statistical model of the reference state. During the detection stage, the current vibration pattern is compared with the reference state, and the novelties can be associated with damage. The vibration pattern is described by the covariance matrix between the accelerometer signals. The mid-range frequencies are used: this range is above the frequencies excited by blade-wind interaction, thus ensuring a good signal-to-noise ratio. Simultaneously, the frequencies are low enough to be able to propagate the entire blade length, so good results can be obtained even using only one actuator. The system is demonstrated on a real 34m blade mounted on a test rig. Using the suggested approach, the system enables detection of, e.g., a 20cm long trailing edge opening under realistic noise conditions. It is also demonstrated that the system provides rough information about damage location. Progression of damage, if any, can also be detected.

  7. Small Wind Electric Systems: A U.S. Consumer's Guide

    Energy Technology Data Exchange (ETDEWEB)

    None

    2007-08-01

    The handbook provides consumers with information to help them determine whether a small wind electric system can provide all or a portion of the energy they need for their home or business based on their wind resource, energy needs, and their economics. Topics discussed in the guide include how to make a home more energy efficient, how to choose the correct turbine size, the parts of a wind electric system, how to determine whether enough wind resource exists, how to choose the best site for a turbine, how to connect a system to the utility grid, and whether it's possible to become independent of the utility grid using wind energy.

  8. Optimal Operation of Plug-In Electric Vehicles in Power Systems with High Wind Power Penetrations

    DEFF Research Database (Denmark)

    Hu, Weihao; Su, Chi; Chen, Zhe

    2013-01-01

    The Danish power system has a large penetration of wind power. The wind fluctuation causes a high variation in the power generation, which must be balanced by other sources. The battery storage based Plug-In Electric Vehicles (PEV) may be a possible solution to balance the wind power variations...... in the power systems with high wind power penetrations. In this paper, the integration of plug-in electric vehicles in the power systems with high wind power penetrations is proposed and discussed. Optimal operation strategies of PEV in the spot market are proposed in order to decrease the energy cost for PEV...

  9. Operating the Irish power system with increased levels of wind power

    DEFF Research Database (Denmark)

    Tuohy, A.; Denny, E.; Meibom, Peter

    2008-01-01

    This paper summarises some of the main impacts of large amounts of wind power installed in the island of Ireland. Using results from various studies performed on this system, it is shown that wind power will impact on all time frames, from seconds to daily planning of the system operation. Results...... from studies examining operation of the system with up to approximately 40% of electricity provided by wind show that some of the most important aspects to be considered include the type of wind turbine technology, the provision of reserve to accommodate wind forecasting error and the method used...

  10. Matching of wind turbine type and system scale to wind conditions; Chiten no fukyo ni taisuru furyoku turbine no keitai to sytem taikaku no seigosei ni tsuite

    Energy Technology Data Exchange (ETDEWEB)

    Wakui, T. [Japan Society for the Promotion of Science, Tokyo (Japan); Tanzawa, Y. [Nippon Institute of Technology, Saitama (Japan); Ota, E. [Waseda University, Tokyo (Japan). School of Science and Engineering; Hashizume, T.

    2000-09-25

    The matching of the wind turbine type and system scale of the stand-alone wind turbine generator system to wind conditions is investigated using our dynamic simulation model. This paper examines three types of wind turbines: the Darrieus-Savonius hybrid wind turbine, the Darrieus turbine proper and the up-wind Propeller turbine. These systems are mainly operated at a constant tip speed ratio, which refers to a maximum power coefficient. As a computed result of the net extracting energy under fluctuations of wind speed and direction, the Darrieus turbine proper has little conformability to wind fluctuations because of its output characteristics. As for other wind turbines, large-scale systems do not always have advantages over small-scale systems as the effect of the dynamic characteristics. Furthermore, it is confirmed that the net extracting power of the Propeller turbine under wind direction fluctuations is much reduced when compared with that of the hybrid wind turbine. Thus, it is concluded that the appropriate wind turbine type and system scale exist for each wind condition. (author)

  11. System Dynamics Simulation of Large-Scale Generation System for Designing Wind Power Policy in China

    Directory of Open Access Journals (Sweden)

    Linna Hou

    2015-01-01

    Full Text Available This paper focuses on the impacts of renewable energy policy on a large-scale power generation system, including thermal power, hydropower, and wind power generation. As one of the most important clean energy, wind energy has been rapidly developed in the world. But in recent years there is a serious waste of wind power equipment and investment in China leading to many problems in the industry from wind power planning to its integration. One way overcoming the difficulty is to analyze the influence of wind power policy on a generation system. This paper builds a system dynamics (SD model of energy generation to simulate the results of wind energy generation policies based on a complex system. And scenario analysis method is used to compare the effectiveness and efficiency of these policies. The case study shows that the combinations of lower portfolio goal and higher benchmark price and those of higher portfolio goal and lower benchmark price have large differences in both effectiveness and efficiency. On the other hand, the combinations of uniformly lower or higher portfolio goal and benchmark price have similar efficiency, but different effectiveness. Finally, an optimal policy combination can be chosen on the basis of policy analysis in the large-scale power system.

  12. A simulation environment for assisting system design of coherent laser doppler wind sensor for active wind turbine pitch control

    Science.gov (United States)

    Shinohara, Leilei; Pham Tran, Tuan Anh; Beuth, Thorsten; Umesh Babu, Harsha; Heussner, Nico; Bogatscher, Siegwart; Danilova, Svetlana; Stork, Wilhelm

    2013-05-01

    In order to assist a system design of laser coherent Doppler wind sensor for active pitch control of wind turbine systems (WTS), we developed a numerical simulation environment for modeling and simulation of the sensor system. In this paper we present this simulation concept. In previous works, we have shown the general idea and the possibility of using a low cost coherent laser Doppler wind sensing system for an active pitch control of WTS in order to achieve a reduced mechanical stress, increase the WTS lifetime and therefore reduce the electricity price from wind energy. Such a system is based on a 1.55μm Continuous-Wave (CW) laser plus an erbium-doped fiber amplifier (EDFA) with an output power of 1W. Within this system, an optical coherent detection method is chosen for the Doppler frequency measurement in megahertz range. A comparatively low cost short coherent length laser with a fiber delay line is used for achieving a multiple range measurement. In this paper, we show the current results on the improvement of our simulation by applying a Monte Carlo random generation method for positioning the random particles in atmosphere and extend the simulation to the entire beam penetrated space by introducing a cylindrical co-ordinate concept and meshing the entire volume into small elements in order to achieve a faster calculation and gain more realistic simulation result. In addition, by applying different atmospheric parameters, such as particle sizes and distributions, we can simulate different weather and wind situations.

  13. Hierarchical parameter estimation of DFIG and drive train system in a wind turbine generator

    Science.gov (United States)

    Pan, Xueping; Ju, Ping; Wu, Feng; Jin, Yuqing

    2017-09-01

    A new hierarchical parameter estimation method for doubly fed induction generator (DFIG) and drive train system in a wind turbine generator (WTG) is proposed in this paper. Firstly, the parameters of the DFIG and the drive train are estimated locally under different types of disturbances. Secondly, a coordination estimation method is further applied to identify the parameters of the DFIG and the drive train simultaneously with the purpose of attaining the global optimal estimation results. The main benefit of the proposed scheme is the improved estimation accuracy. Estimation results confirm the applicability of the proposed estimation technique.

  14. CleverFarm - A superSCADA system for wind farms

    DEFF Research Database (Denmark)

    Juhl, A.; Hansen, K.G.; Giebhardt, J.;

    2004-01-01

    The CleverFarm project started out to build an integrated monitoring system for wind farms, where all information would be available and could be used across the wind farm for maintenance and component health assessments. This would enable wind farmoperators to prioritise their efforts, since the...

  15. Operation and control of a DC-grid offshore wind farm under DC transmission system faults

    DEFF Research Database (Denmark)

    Deng, Fujin; Chen, Zhe

    2013-01-01

    So far, all existing offshore wind farms have an ac collection system, and the collected power in the offshore wind farm is sent to an onshore ac grid through high-voltage ac (HVAC) or DC (HVDC) transmission lines. However, future of fshore wind farms may use dc also for power collection. Consequ...

  16. Overview of the Energy Storage Systems for the Wind Power Integration Enhancement

    DEFF Research Database (Denmark)

    Swierczynski, Maciej Jozef; Teodorescu, Remus; Rasmussen, Claus Nygaard

    2010-01-01

    As the installed worldwide wind energy capacity increases about 30% annually and Kyoto protocol that came in force in 2005, wind penetration level in power system is considered to significantly increase in near future. Due to increased penetration and nature of the wind, especially its...

  17. Electric Vehicles for Improved Operation of Power Systems with High Wind Power Penetration

    DEFF Research Database (Denmark)

    Larsen, Esben; Chandrashekhara, Divya K; Østergaard, Jacob

    2008-01-01

    In a power system with a high share of wind energy the wind fluctuation causes a variation in the power generation, which must be compensated from other sources. The situation in Denmark with a penetration of more than 20% wind in yearly average is presented. The introduction of electric drive ve...

  18. System Aspects and Modulation Strategies of an HVDC-based Converter System for Wind Farms

    Energy Technology Data Exchange (ETDEWEB)

    Meier, Stephan

    2009-05-15

    In this thesis, a new HVDC-based converter system for wind farms is investigated. It is based on a mutually commutated soft-switching converter system and provides a unique integrated solution for the wind turbine generator drive systems, the wind turbine interconnection, and the power conversion for HVDC transmission. In a wind farm, the mutually commutated converter system is a distributed system. A medium-frequency collection grid connects the converter station, equipped with a single-phase voltage source converter and a medium-frequency transmission transformer, with the wind turbines, each containing a cyclo converter and a medium-frequency distribution transformer. In this thesis, various system aspects regarding the application of a distributed mutually commutated converter system in a wind farm are investigated. Special attention is paid to the design of a medium-frequency collection grid that has an acceptable level of transient over voltages, the design of medium-frequency transformers with suitable magnetic, electric and thermal properties, and the development of a strategy to commutate the voltage source converter during low power generation. In order to adapt the mutually commutated converter system for an application in a wind farm, it had to be further developed. Different carrier-based and space-vector oriented modulation methods have been investigated. It turns out that for any load angle there is a quasi-discontinuous pulse width modulation strategy that can produce the same pulse patterns as space vector modulation. In addition, a modulation strategy has been developed that allows to replace the IGBTs in the cyclo converter with cheap, robust, and reliable fast thyristors, despite their absence of turn-off capability. The feasibility of different modulation strategies for mutually commutated converter systems has been verified on a down-scaled prototype converter system with both IGBT- and thyristor-based cyclo converters. Finally, a feasible

  19. Development of large scale wind energy conservation system. Development of large scale wind energy conversion system; Ogata furyoku hatsuden system no kaihatsu. Ogata furyoku hatsuden system no kaihatsu

    Energy Technology Data Exchange (ETDEWEB)

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

    1994-12-01

    Described herein are the results of the FY1994 research program for development of large scale wind energy conversion system. The study on technological development of key components evaluates performance of, and confirms reliability and applicability of, hydraulic systems centered by those equipped with variable pitch mechanisms and electrohydraulic servo valves that control them. The study on blade conducts fatigue and crack-propagation tests, which show that the blades developed have high strength. The study on speed-increasing gear conducts load tests, confirming the effects of reducing vibration and noise by modification of the gear teeth. The study on NACELLE cover conducts vibration tests to confirm its vibration characteristics, and analyzes three-dimensional vibration by the finite element method. Some components for a 500kW commercial wind mill are fabricated, including rotor heads, variable pitch mechanisms, speed-increasing gears, YAW systems, and hydraulic control systems. The others fabricated include a remote supervisory control system for maintenance, system to integrate the wind mill into a power system, and electrical control devices in which site conditions, such as atmospheric temperature and lightening, are taken into consideration.

  20. Costa de Cocos wind-diesel hybrid power system

    Energy Technology Data Exchange (ETDEWEB)

    Ellis, Abraham; Estrada, Luis [Southwest Thechnology Development Institute, New Mexico State University, Las Cruces (United States); Newcomb, Charles; Corbus, David [National Renewable Energy Laboratory, CO (United States)

    2000-07-01

    This paper describes the performance and reliability of the Costa de Cocos wind-diesel hybrid system. Located in a remote coastal area in southern Mexico, the system is exposed to high temperatures and humidity, slat spray and occasional storm wind. It continues to supply the load, but has experienced some problems associated with inverter failure, battery degradation and corrosion. Inadequate operation and maintenance practices have also caused some problems. The information collected to date from technical visits and remote data collection is discussed in this paper. The system design and operation are also covered. [Spanish] Este articulo describe el rendimiento y la confiabilidad del sistema hibrido de viento y diesel en Costa de Cocos. Localizado en una costa remota en la parte sur de Mexico, el sistema esta expuesto a altas temperaturas y humedad, fuerte brisa marina y vientos ocasionales de tormenta. Sigue suministrando la carga, pero ha experimentado algunos problemas asociados con fallas del inversor, la degradacion de las baterias y corrosion. La inadecuada operacion y practicas de mantenimiento tambien han causado algunos problemas. Este articulo analiza la informacion reunida a la fecha sobre las visitas tecnicas y la recoleccion remota de datos. Tambien incluye el disel del sistema y su operacion.

  1. 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.

  2. Feasibility study of a hybrid wind turbine system – integration with compressed air energy storage

    OpenAIRE

    Sun, Hao; Luo, Xing; Wang, Jihong

    2015-01-01

    Wind has been recognized as one of major realistic clean energy sources for power generation to meet the continuously increased energy demand and to achieve the carbon emission reduction targets. However, the utilisation of wind energy encounters an inevitable challenge resulting from the nature of wind intermittency. To address this, the paper presents the recent research work at Warwick on the feasibility study of a new hybrid system by integrating a wind turbine with compressed air energy ...

  3. Small Wind Electric Systems: A Maryland Consumer's Guide (Revised)

    Energy Technology Data Exchange (ETDEWEB)

    2009-08-01

    Small Wind Electric Systems: A Maryland Consumer's Guide provides consumers with information to help them determine whether a small wind electric system can provide all or a portion of the energy they need for their home or business based on their wind resource, energy needs, and their economics. Topics discussed in the guide include how to make a home more energy efficient, how to choose the correct turbine size, the parts of a wind electric system, how to determine whether enough wind resource exists, how to choose the best site for a turbine, how to connect a system to the utility grid, and whether it's possible to become independent of the utility grid using wind energy. In addition, the cover of the guide contains a regional wind resource map and a list of incentives and contacts for more information.

  4. Small Wind Electric Systems: A Guide Produced for the Tennessee Valley Authority (Revised) (Brochure)

    Energy Technology Data Exchange (ETDEWEB)

    2009-06-01

    Small Wind Electric Systems: A Guide Produced for the Tennessee Valley Authority provides consumers with information to help them determine whether a small wind electric system can provide all or a portion of the energy they need for their home or business based on their wind resource, energy needs, and their economics. Topics discussed in the guide include how to make a home more energy efficient, how to choose the correct turbine size, the parts of a wind electric system, how to determine whether enough wind resource exists, how to choose the best site for a turbine, how to connect a system to the utility grid, and whether it's possible to become independent of the utility grid using wind energy. In addition, the cover of the guide contains a regional wind resource map and a list of incentives and contacts for more information.

  5. Adequacy of operating reserves for power systems in future european wind power scenarios

    DEFF Research Database (Denmark)

    Das, Kaushik; Litong-Palima, Marisciel; Maule, Petr

    2015-01-01

    operating reserves. To study the effects of these imbalances, anticipated wind scenarios for European power systems are modelled for 2020 and 2030. Wind power forecasts for different time scales and real-time available wind power are modelled. Based on these studies, this paper qualitatively analyzes......Wind power generation is expected to increase in Europe by large extent in future. This will increase variability and uncertainty in power systems. Imbalances caused due to uncertainty in wind power forecast can trigger frequency instability in the system. These imbalances are handled using...... the adequacy of primary and secondary reserves requirements for future European power systems. This paper also discusses the challenges due to the uncertainty in wind power forecasts and their possible solutions for wind installation scenarios for 2020 and 2030....

  6. Wind-To-Hydrogen Project: Operational Experience, Performance Testing, and Systems Integration

    Energy Technology Data Exchange (ETDEWEB)

    Harrison, K. W.; Martin, G. D.; Ramsden, T. G.; Kramer, W. E.; Novachek, F. J.

    2009-03-01

    The Wind2H2 system is fully functional and continues to gather performance data. In this report, specifications of the Wind2H2 equipment (electrolyzers, compressor, hydrogen storage tanks, and the hydrogen fueled generator) are summarized. System operational experience and lessons learned are discussed. Valuable operational experience is shared through running, testing, daily operations, and troubleshooting the Wind2H2 system and equipment errors are being logged to help evaluate the reliability of the system.

  7. SYSTEMIC TOXIC REACTIONS TO LOCAL ANESTHETICS

    Science.gov (United States)

    Moore, Daniel C.; Green, John

    1956-01-01

    The topical use of anesthetic agents involves an element of risk. Systemic toxic reactions are rare, but they do occur and may result in death. When a reaction occurs from a topical application, it usually progresses rapidly to respiratory and cardiovascular collapse, and thus therapy must be instituted with more haste to avoid deaths. Fatal systemic toxic reactions from topically administered anesthetic drugs are, in effect, usually not due to well informed use of the drug but to misuse owing to less than complete understanding of absorption. Emphasis is placed on the causes, prophylaxis and treatment of severe systemic toxic reactions which follow the topical application of local anesthetic drugs. If systemic toxic reactions resulting from a safe dose of a local anesthetic agent are correctly treated, there will usually follow an uneventful recovery rather than a catastrophe. PMID:13343009

  8. A comparative study between three sensorless control strategies for PMSG in wind energy conversion system

    Energy Technology Data Exchange (ETDEWEB)

    Brahmi, Jemaa; Krichen, Lotfi; Ouali, Abderrazak [Advanced Control and Energy Management Research Unit ENIS, Department of Electrical Engineering, University of Sfax, 3038 Sfax (Tunisia)

    2009-09-15

    This paper presents a comparative study of sliding mode, artificial neural network and model reference adaptive speed observers for a speed sensorless permanent magnet synchronous generator (PMSG) in wind energy conversion system (WECS). Wind velocity and position sensorless operating methods for wind generation system using observer are proposed only by measuring phase voltages and currents. Maximum wind energy extraction is achieved by running the wind turbine generator in variable-speed mode. In addition the three speed observers are compared to verify the robustness against parameter variations. (author)

  9. Summertime coastal current reversal opposing offshore forcing and local wind near the middle east coast of Korea: Observation and dynamics

    Science.gov (United States)

    Park, Jae-Hyoung; Chang, Kyung-Il; Nam, SungHyun

    2016-07-01

    A 6 year long current measurement at a buoy station off the middle east coast of Korea reveals an equatorward reversal of coastal current in summer opposing poleward local wind stress and offshore boundary current. The current reversal extends about 40 km offshore from the coast and is concurrent with warming and freshening of water column. Estimates of the depth-averaged alongshore momentum balance suggest a major balance between the alongshore pressure gradient and the lateral friction. Sources of the pressure gradient for the summertime current reversal are identified as the alongshore buoyancy gradient driven by the wind curl gradient and the prevalence of warmer and lower salinity water in the north. Alongshore pressure gradient and velocity induced by the wind curl gradient are quantified, which yields the observed seasonal current reversal.

  10. Assessment of locally manufactured small wind turbines as an appropriate technology for the electrification of the Caribbean Coast of Nicaragua

    Directory of Open Access Journals (Sweden)

    Pedro Neves

    2015-02-01

    Full Text Available This article presents an assessment of the challenges facing the use of small locally manufactured wind turbines as a rural electrification solution for the Caribbean Coast of Nicaragua. Strongly based on the authors work experience at the non-profit, non-governmental organization blueEnergy, this assessment makes an objective analysis of the technical, social, economic and organizational challenges faced by blueEnergy when using small wind turbines for rural electrification. The article provides detail on the challenges faced and puts forward methodologies and technologies to overcome or to detect and avoid these. Based on the challenges faced, a set of key factors that are essential for the success of small wind turbines in other contexts is proposed, together with two methodologies for a preliminary feasibility assessment.

  11. Power control and management of the grid containing largescale wind power systems

    Science.gov (United States)

    Aula, Fadhil Toufick

    The ever increasing demand for electricity has driven many countries toward the installation of new generation facilities. However, concerns such as environmental pollution and global warming issues, clean energy sources, high costs associated with installation of new conventional power plants, and fossil fuels depletion have created many interests in finding alternatives to conventional fossil fuels for generating electricity. Wind energy is one of the most rapidly growing renewable power sources and wind power generations have been increasingly demanded as an alternative to the conventional fossil fuels. However, wind power fluctuates due to variation of wind speed. Therefore, large-scale integration of wind energy conversion systems is a threat to the stability and reliability of utility grids containing these systems. They disturb the balance between power generation and consumption, affect the quality of the electricity, and complicate load sharing and load distribution managing and planning. Overall, wind power systems do not help in providing any services such as operating and regulating reserves to the power grid. In order to resolve these issues, research has been conducted in utilizing weather forecasting data to improve the performance of the wind power system, reduce the influence of the fluctuations, and plan power management of the grid containing large-scale wind power systems which consist of doubly-fed induction generator based energy conversion system. The aims of this research, my dissertation, are to provide new methods for: smoothing the output power of the wind power systems and reducing the influence of their fluctuations, power managing and planning of a grid containing these systems and other conventional power plants, and providing a new structure of implementing of latest microprocessor technology for controlling and managing the operation of the wind power system. In this research, in order to reduce and smooth the fluctuations, two

  12. Quantifying the effects of LUCCs on local temperatures, precipitation, and wind using the WRF model.

    Science.gov (United States)

    Lian, Lishu; Li, Baofu; Chen, Yaning; Chu, Cuicui; Qin, Yanhua

    2017-09-11

    Land use/cover changes (LUCCs) are an important cause of regional climate changes, but the contribution of LUCCs to regional climate changes is not clear. In this study, the Weather Research and Forecasting (WRF) model and statistical methods were used to investigate changes in meteorologic variables in January, April, July, and October 2013 due to local LUCCs from 1990 to 2010 in southern Shandong province, China. The results indicate that the WRF model simulates temperatures in the region well, with high correlation coefficients (0.86-0.97, p < 0.001) between the modeled and measured values. The model simulates precipitation less well, with correlation coefficients of 0.41-0.91, but they are all at statistically significant levels, with p < 0.05. During the 20-year period, the LUCCs in the study area consisted mainly of conversions from dry land to urbanized land (747.3 km(2)) and bare/sparse vegetation (132.4 km(2)). The LUCCs caused a 0.16 °C temperature increase in January and October and 0.01 and 0.18 °C temperature decreases in April and July, respectively. The range of temperature changes over mixed forest and water bodies due to the LUCCs was wide (0.39-1.31 °C) and was narrower over deciduous broadleaf forest and wetland (0.01 to 0.06 °C). The LUCCs did not change the precipitation greatly in January, April, and October but did affect the precipitation in July substantially, causing a decrease of 23.71 mm. The LUCCs did not affect wind speed and direction substantially during these four months: average wind speeds increased by 0.02 and 0.01 m/s in January and October, respectively, and decreased by 0.02 and 0.05 m/s in April and July, respectively. Overall, The LUCCs affected spring temperatures the least and summer precipitation the most.

  13. Operation of a Wind Turbine-Flywheel Energy Storage System under Conditions of Stochastic Change of Wind Energy

    Science.gov (United States)

    2014-01-01

    The paper presents the issues of a wind turbine-flywheel energy storage system (WT-FESS) operation under real conditions. Stochastic changes of wind energy in time cause significant fluctuations of the system output power and as a result have a negative impact on the quality of the generated electrical energy. In the author's opinion it is possible to reduce the aforementioned effects by using an energy storage of an appropriate type and capacity. It was assumed that based on the technical parameters of a wind turbine-energy storage system and its geographical location one can determine the boundary capacity of the storage, which helps prevent power cuts to the grid at the assumed probability. Flywheel energy storage was selected due to its characteristics and technical parameters. The storage capacity was determined based on an empirical relationship using the results of the proposed statistical and energetic analysis of the measured wind velocity courses. A detailed algorithm of the WT-FESS with the power grid system was developed, eliminating short-term breaks in the turbine operation and periods when the wind turbine power was below the assumed level. PMID:25215326

  14. Operation of a wind turbine-flywheel energy storage system under conditions of stochastic change of wind energy.

    Science.gov (United States)

    Tomczewski, Andrzej

    2014-01-01

    The paper presents the issues of a wind turbine-flywheel energy storage system (WT-FESS) operation under real conditions. Stochastic changes of wind energy in time cause significant fluctuations of the system output power and as a result have a negative impact on the quality of the generated electrical energy. In the author's opinion it is possible to reduce the aforementioned effects by using an energy storage of an appropriate type and capacity. It was assumed that based on the technical parameters of a wind turbine-energy storage system and its geographical location one can determine the boundary capacity of the storage, which helps prevent power cuts to the grid at the assumed probability. Flywheel energy storage was selected due to its characteristics and technical parameters. The storage capacity was determined based on an empirical relationship using the results of the proposed statistical and energetic analysis of the measured wind velocity courses. A detailed algorithm of the WT-FESS with the power grid system was developed, eliminating short-term breaks in the turbine operation and periods when the wind turbine power was below the assumed level.

  15. Operation of a Wind Turbine-Flywheel Energy Storage System under Conditions of Stochastic Change of Wind Energy

    Directory of Open Access Journals (Sweden)

    Andrzej Tomczewski

    2014-01-01

    Full Text Available The paper presents the issues of a wind turbine-flywheel energy storage system (WT-FESS operation under real conditions. Stochastic changes of wind energy in time cause significant fluctuations of the system output power and as a result have a negative impact on the quality of the generated electrical energy. In the author’s opinion it is possible to reduce the aforementioned effects by using an energy storage of an appropriate type and capacity. It was assumed that based on the technical parameters of a wind turbine-energy storage system and its geographical location one can determine the boundary capacity of the storage, which helps prevent power cuts to the grid at the assumed probability. Flywheel energy storage was selected due to its characteristics and technical parameters. The storage capacity was determined based on an empirical relationship using the results of the proposed statistical and energetic analysis of the measured wind velocity courses. A detailed algorithm of the WT-FESS with the power grid system was developed, eliminating short-term breaks in the turbine operation and periods when the wind turbine power was below the assumed level.

  16. The Modeling and Control of a Wind Farm and Grid Interconnection in a multi-machine system

    OpenAIRE

    Skolthanarat, Siriya

    2009-01-01

    This dissertation focuses on the modeling and control of WECS (Wind Energy Conversion System) in a multi-machine system. As one of the fastest growing renewable energy resources, the trend of wind energy changes to variable speed wind turbines. The concept of the variable speed is based on the variable speed according to the instantaneous wind speed of wind turbines. Since the utility grid requires the stable frequency and magnitude voltages, there must be grid interconnection of the wind far...

  17. Integration of large wind farms into weak power grids. Emphasis on the Ethiopian interconnected system (ICS)

    Energy Technology Data Exchange (ETDEWEB)

    Bantyirga Gessesse, Belachew

    2013-07-18

    The impact of increased wind power on the steady state and dynamic behavior of the Ethiopian power system is the main focus of this thesis. The integration of wind power to the existing grid with conventional generators introduces new set of challenges regarding system security and operational planning, the main cause of the difference arising from the uncertainty of the primary source of energy and the response time following a disturbance. For incorporating wind turbine models into the overall dynamic model of the system and investigating the effect of wind on the dynamic behavior of the wind first models of wind turbine components were put together by reviewing the current state of the art in wind turbine modeling and control concepts. The theoretical insight thus gained was applied to the Ethiopian power system as a case study. Since the models of the installed turbines were either not available or incomplete, an alternative modeling approach based on generic models was adopted. The generic model, in addition to obviating the need for technology or manufacturer specific models, reduces the complexity the dynamic model. Using this procedure, generic dynamic models for wind farm in the system were developed. The capability of dynamic models to reproduce the dynamic response of the system has been verified by comparing simulation results obtained with a detailed and generic wind farm model. It could be shown that the generic wind turbine model is simple, but accurate enough to represent any wind turbine types or entire wind farms for power system stability analysis. The next task was the study of the effect of increased wind power level on the general behavior of the Ethiopian system. It is observed that overall the impact of wind turbines on the operational indices of the system was -as could be expected- more pronounced in the vicinity of the wind farm. But the power angle oscillation following a disturbance was observed across the whole system. Further, as a

  18. Broadband measuring system for unsteady flow investigation in wind tunnel

    Science.gov (United States)

    Biriukov, V. I.; Garifullin, M. F.; Korneeva, D. B.; Slitinskaya, A. Ju.

    2016-10-01

    Due to increasingly tough requirements to the accuracy and informativity of the wind tunnel experiments, the urgency has grown of the unsteady flows research. A distinctive feature of such studies is synchronous multichannel measurements of rapidly changing in time process parameters (with a broadband spectrum and characteristic frequencies of 0 Hz to 1000 Hz and above) and also the need for fast processing and storage of large volumes of the data received. To solve these problems and to meet the requirements, TsAGI has developed a measuring system (MS) and the corresponding software. The basic purpose of MS is to conduct transonic buffeting research in T-128 wind tunnel. Besides, it can be used to study separated flow regimes, aeroelastic vibrations, including: classic flutter, stall flutter, limit cycle oscillations, etc. The MS can be used also to study a variety of transient regimes. It is possible to expand the system further on to enhance its performance without introducing any fundamental changes in its structure and software, and without breaking its operability for the period of modernization.

  19. A cooling system for buildings using wind energy

    Energy Technology Data Exchange (ETDEWEB)

    Daiyan, H. [Islamic Azad Univ., Semnan Branch (Iran)

    2007-05-15

    In Iranian historical architecture wind towers are used for cooling and ventilation. A wind tower is a tall structure that stands on the building. A wind tower is used in dray land, and only uses wind energy for conditioning. Its technology dates back over 1000 years. Wind towers were designed according to several parameters, some of the most important of which were building type, cooling space volume, wind direction and velocity and ambient temperature. This paper studies wind towers and characterizes airflow route and explains how to decrease temperature. To confirm the quality of the wind tower, some experiments in a case study shows it can decrease room temperature on comfort range and room temperature is almost constant on during day. (au)

  20. Wind power integration into the automatic generation control of power systems with large-scale wind power

    Directory of Open Access Journals (Sweden)

    Abdul Basit

    2014-10-01

    Full Text Available Transmission system operators have an increased interest in the active participation of wind power plants (WPP in the power balance control of power systems with large wind power penetration. The emphasis in this study is on the integration of WPPs into the automatic generation control (AGC of the power system. The present paper proposes a coordinated control strategy for the AGC between combined heat and power plants (CHPs and WPPs to enhance the security and the reliability of a power system operation in the case of a large wind power penetration. The proposed strategy, described and exemplified for the future Danish power system, takes the hour-ahead regulating power plan for generation and power exchange with neighbouring power systems into account. The performance of the proposed strategy for coordinated secondary control is assessed and discussed by means of simulations for different possible future scenarios, when wind power production in the power system is high and conventional production from CHPs is at a minimum level. The investigation results of the proposed control strategy have shown that the WPPs can actively help the AGC, and reduce the real-time power imbalance in the power system, by down regulating their production when CHPs are unable to provide the required response.

  1. Adequacy assessment of composite generation and transmission systems incorporating wind energy conversion systems

    Science.gov (United States)

    Gao, Yi

    The development and utilization of wind energy for satisfying electrical demand has received considerable attention in recent years due to its tremendous environmental, social and economic benefits, together with public support and government incentives. Electric power generation from wind energy behaves quite differently from that of conventional sources. The fundamentally different operating characteristics of wind energy facilities therefore affect power system reliability in a different manner than those of conventional systems. The reliability impact of such a highly variable energy source is an important aspect that must be assessed when the wind power penetration is significant. The focus of the research described in this thesis is on the utilization of state sampling Monte Carlo simulation in wind integrated bulk electric system reliability analysis and the application of these concepts in system planning and decision making. Load forecast uncertainty is an important factor in long range planning and system development. This thesis describes two approximate approaches developed to reduce the number of steps in a load duration curve which includes load forecast uncertainty, and to provide reasonably accurate generating and bulk system reliability index predictions. The developed approaches are illustrated by application to two composite test systems. A method of generating correlated random numbers with uniform distributions and a specified correlation coefficient in the state sampling method is proposed and used to conduct adequacy assessment in generating systems and in bulk electric systems containing correlated wind farms in this thesis. The studies described show that it is possible to use the state sampling Monte Carlo simulation technique to quantitatively assess the reliability implications associated with adding wind power to a composite generation and transmission system including the effects of multiple correlated wind sites. This is an important

  2. Bessakerfjellet wind park: skepticism turned to local enthusiasm; Bessakerfjellet vindpark: Snudde skepsis til lokal jubel

    Energy Technology Data Exchange (ETDEWEB)

    2010-07-01

    TroenderEnergi started the dialogue with landowners and licensees before they submitted an application for development of Bessakerfjellet Wind Farm to NVE. With that they laid the foundation for the creation of one of the most profitable wind farms. (AG)

  3. Stand-alone wind system with Vanadium Redox Battery energy storage

    DEFF Research Database (Denmark)

    Teodorescu, Remus; Barote, L.; Weissbach, R.

    2008-01-01

    Energy storage devices are required for power balance and power quality in stand alone wind energy systems. A Vanadium Redox Flow Battery (VRB) system has many features which make its integration with a stand-alone wind energy system attractive. This paper proposes the integration of a VRB system...

  4. Influence of Wind Plant Ancillary Voltage Control on System Small Signal Stability

    DEFF Research Database (Denmark)

    Su, Chi; Chen, Zhe

    2012-01-01

    As a common tendency, large-scale wind farms are increasingly connected to the transmission system of modern power grids. This introduces some new challenges to the connected power systems, and the transmission system operators (TSOs) have to put some new requirements as part of the grid codes...... on the integration of wind farms. One common requirement to wind farms is the function of system voltage control which can be implemented in the grid-side convertor controller of a variable speed wind turbine. This ancillary voltage control provided by wind farms could have some influence on the system small signal...... stability. This paper implements an ancillary voltage control strategy on a direct-drive-full-convertor-based wind farm and studies its influence on the damping ratio values of the dominant oscillation mode within the connected power system. All the calculations and simulations are conducted in DIg...

  5. On Locality in Distributed Storage Systems

    CERN Document Server

    Rawat, Ankit Singh

    2012-01-01

    This paper studies the design of codes for distributed storage systems (DSS) that enable local repair in the event of node failure. This paper presents locally repairable codes based on low degree multivariate polynomials. Its code construction mechanism extends work on Noisy Interpolating Set by Dvir et al. \\cite{dvir2011}. The paper presents two classes of codes that allow node repair to be performed by contacting 2 and 3 surviving nodes respectively. It further shows that both classes are good in terms of their rate and minimum distance, and allow their rate to be bartered for greater flexibility in the repair process.

  6. Wind Forcing Experiments in the California Current System.

    Science.gov (United States)

    boundary on which either free-slip or zero-slip boundary conditions are imposed. Time-invariant winds, either with or without a component of wind stress curl...deeper and wider than the observed jet. Finally, the inclusion of wind stress curl and the zero-slip boundary condition are demonstrated to be important elements in model simulations of the coastal jet.

  7. Integration of Wind Energy Systems into Power Engineering Education Program at UW-Madison

    Energy Technology Data Exchange (ETDEWEB)

    Venkataramanan, Giri [Univ. of Wisconsin, Madison, WI (United States); Lesieutre, Bernard [Univ. of Wisconsin, Madison, WI (United States); Jahns, Thomas [Univ. of Wisconsin, Madison, WI (United States); Desai, Ankur R [Univ. of Wisconsin, Madison, WI (United States)

    2012-09-01

    This project has developed an integrated curriculum focused on the power engineering aspects of wind energy systems that builds upon a well-established graduate educational program at UW- Madison. Five new courses have been developed and delivered to students. Some of the courses have been offered on multiple occasions. The courses include: Control of electric drives for Wind Power applications, Utility Applications of Power Electronics (Wind Power), Practicum in Small Wind Turbines, Utility Integration of Wind Power, and Wind and Weather for Scientists and Engineers. Utility Applications of Power Electronics (Wind Power) has been provided for distance education as well as on-campus education. Several industrial internships for students have been organized. Numerous campus seminars that provide discussion on emerging issues related to wind power development have been delivered in conjunction with other campus events. Annual student conferences have been initiated, that extend beyond wind power to include sustainable energy topics to draw a large group of stakeholders. Energy policy electives for engineering students have been identified for students to participate through a certificate program. Wind turbines build by students have been installed at a UW-Madison facility, as a test-bed. A Master of Engineering program in Sustainable Systems Engineering has been initiated that incorporates specializations that include in wind energy curricula. The project has enabled UW-Madison to establish leadership at graduate level higher education in the field of wind power integration with the electric grid.

  8. Stochastic Modeling of Turbulence-Driven Systems: Application to Wind Energy

    Science.gov (United States)

    Milan, P.; Waechter, M.; Peinke, J.

    2010-11-01

    The recent increase in the exploitation of the wind energy resource stresses the need for fundamental research in fluid dynamics. The complex wind inflows that drive wind turbines affect their availability in terms of electric power production, as well as in operation lifetime. Short-scale turbulent effects in the wind such as intermittency, as well as large-scale atmospheric non-stationarity lead to ever-changing power signals fed into the electric grid. This calls for a theoretical classification of wind energy phenomena into complex, turbulence-driven systems. Our raising dependence on wind energy requires a better understanding of these phenomena, as well as reliable models. A stochastic model is proposed as an alternative to standard wind energy models that often neglect turbulent effects or CFD models that cannot decribe large wind turbines yet. This model is based on the stochastic equation of Langevin that can simulate these complex systems after their proper characterization. This stochastic model can be applied separately on both atmospheric wind speed signals as well as wind turbine power production signals, after the wind turbine was characterized properly. The signals generated display the proper statistics and represent fast and flexible models for wind energy applications such as monitoring, availability prediction or grid integration. A future analysis of fatigue loads is also under development.

  9. 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)

  10. 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)

  11. Small UAS-Based Wind Feature Identification System Part 1: Integration and Validation

    Directory of Open Access Journals (Sweden)

    Leopoldo Rodriguez Salazar

    2016-12-01

    Full Text Available This paper presents a system for identification of wind features, such as gusts and wind shear. These are of particular interest in the context of energy-efficient navigation of Small Unmanned Aerial Systems (UAS. The proposed system generates real-time wind vector estimates and a novel algorithm to generate wind field predictions. Estimations are based on the integration of an off-the-shelf navigation system and airspeed readings in a so-called direct approach. Wind predictions use atmospheric models to characterize the wind field with different statistical analyses. During the prediction stage, the system is able to incorporate, in a big-data approach, wind measurements from previous flights in order to enhance the approximations. Wind estimates are classified and fitted into a Weibull probability density function. A Genetic Algorithm (GA is utilized to determine the shaping and scale parameters of the distribution, which are employed to determine the most probable wind speed at a certain position. The system uses this information to characterize a wind shear or a discrete gust and also utilizes a Gaussian Process regression to characterize continuous gusts. The knowledge of the wind features is crucial for computing energy-efficient trajectories with low cost and payload. Therefore, the system provides a solution that does not require any additional sensors. The system architecture presents a modular decentralized approach, in which the main parts of the system are separated in modules and the exchange of information is managed by a communication handler to enhance upgradeability and maintainability. Validation is done providing preliminary results of both simulations and Software-In-The-Loop testing. Telemetry data collected from real flights, performed in the Seville Metropolitan Area in Andalusia (Spain, was used for testing. Results show that wind estimation and predictions can be calculated at 1 Hz and a wind map can be updated at 0.4 Hz

  12. Small UAS-Based Wind Feature Identification System Part 1: Integration and Validation

    Science.gov (United States)

    Rodriguez Salazar, Leopoldo; Cobano, Jose A.; Ollero, Anibal

    2016-01-01

    This paper presents a system for identification of wind features, such as gusts and wind shear. These are of particular interest in the context of energy-efficient navigation of Small Unmanned Aerial Systems (UAS). The proposed system generates real-time wind vector estimates and a novel algorithm to generate wind field predictions. Estimations are based on the integration of an off-the-shelf navigation system and airspeed readings in a so-called direct approach. Wind predictions use atmospheric models to characterize the wind field with different statistical analyses. During the prediction stage, the system is able to incorporate, in a big-data approach, wind measurements from previous flights in order to enhance the approximations. Wind estimates are classified and fitted into a Weibull probability density function. A Genetic Algorithm (GA) is utilized to determine the shaping and scale parameters of the distribution, which are employed to determine the most probable wind speed at a certain position. The system uses this information to characterize a wind shear or a discrete gust and also utilizes a Gaussian Process regression to characterize continuous gusts. The knowledge of the wind features is crucial for computing energy-efficient trajectories with low cost and payload. Therefore, the system provides a solution that does not require any additional sensors. The system architecture presents a modular decentralized approach, in which the main parts of the system are separated in modules and the exchange of information is managed by a communication handler to enhance upgradeability and maintainability. Validation is done providing preliminary results of both simulations and Software-In-The-Loop testing. Telemetry data collected from real flights, performed in the Seville Metropolitan Area in Andalusia (Spain), was used for testing. Results show that wind estimation and predictions can be calculated at 1 Hz and a wind map can be updated at 0.4 Hz. Predictions

  13. Calculation of local scour around wind turbine's pile of offshore wind farm%海上风电场风机桩基局部冲刷计算

    Institute of Scientific and Technical Information of China (English)

    王卫远; 杨娟; 李睿元

    2012-01-01

    建设海上风电场时,风机所处的海洋环境十分复杂,在风、浪、流等气象水文要素的影响下,风机桩基周围会出现冲刷坑,进而影响风机基础的稳定.因此,风机桩基的局部冲刷深度是工程设计的重要参数.采用埕岛油田海洋平台桩基局部冲刷现场观测资料,对国内常用的2个计算桩基局部冲刷深度的经验公式(韩海骞公式和王汝凯公式)进行验证,运用波流合成速度代替纯潮流速度.结果表明该海域波浪对泥沙的作用不可忽略.韩海骞公式重新计算的结果与实测值吻合良好.%When building the offshore wind farm, the marine environment of wind turbine is very complex. Scour hole around wind turbine's pile will form because of the influence of meteorology arid hydrology factors, such as wind,wave,current,and so on.It will affect the stability of wind turbine.Therefore,the local scour depth of wind turbine is an important parameter for engineering design. Based on the field observation data of the piles in Chengdao oil field,two commonly used empirical formulas (HAN Hai-qian and WANG Ru-kai) were verified.The synthesis speed of wave and current was used to replace the pure tidal current speed.The results show that the role of wave on sand can not be ignored in this area.The re-calculated result by HAN Hai-qian formula is in good agreement with measured result,and the results have some reference value to the actual project.

  14. Optimizing wind pumps system for crop irrigation based on wind data processing

    Science.gov (United States)

    Ruiz, Fernando; Tarquis, Ana M.; Sanchez, Raúl; Garcia, Jose Luis

    2015-04-01

    Crop irrigation is a major consumer of energy that can be resolved with renewable ones, such as wind, which has experienced recent developments in the area of power generation. Therefore, wind power can play an interesting role in irrigation projects in different areas [1]. A simple methodology has been developed in previous papers for technical evaluation of windmills for irrigation water pumping [2]. This methodology can determine the feasibility of the technology and the levels of daily irrigation demand satisfied by windmills. The present work compared the possibilities of this methodology adjusting the three-hourly wind velocity to the Weibull II distribution function, without considering the time sequence [2], or processing wind data using time series analysis. The study was applied to practical cases of wind pumps for irrigation of crops, both in the outside (corn) and inside greenhouses (tomato). The analysis showed that the use of three hourly time series analysis supplied a more realistic modelling of the situation with a better optimization of the water storage tank of the wind pump facility taking into account the risk of calm periods in which the pumping is null. A factor to consider in this study is available precision of the wind sampling rate. References [1] Díaz-Méndez, R., Adnan Rasheed, M. Peillón, A. Perdigones, R. Sánchez, A.M. Tarquis, José L. García-Fernández. Wind pumps for irrigating greenhouse crops: comparison in different socio-economical frameworks. Biosystems Engineering, 128, 21-28, 2014. [2] Peillón, M., Sánchez, R., Tarquis, A.M., García, J.L. The use of wind pumps for greenhouse microirrigation: A case study for tomato in Cuba. Agricultural Water Management, 120, 107-114, 2013.

  15. The Control System Simulation of Variable-Speed Constant-Frequency Wind Turbine

    Institute of Scientific and Technical Information of China (English)

    窦金延; 曹娜

    2010-01-01

    <正>In general,Variable-Speed Constant Frequency (VSCF)Wind generation system is controlled by stator voltage orientation method which based on the mathematic model of VSCF Wind generation system and discussed the control strategy.Present the whole dynamic control model of variable-speed wind generator system in MATLAB/ Simulink,and the simulation results confirm the validity and effectiveness of the proposed control strategy.

  16. How to improve the design of the electrical system in future wind power plants

    DEFF Research Database (Denmark)

    Arana, I.; Kocewiak, Lukasz Hubert; Holbøll, J.

    2009-01-01

    is to improve the understanding of the main electrical components in wind farms, based on available information, measurement data and simulation tools. The aim of these projects is to obtain validated models of wind turbine (WT) generators, WT converters, WT transformers, submarine cables, circuit breakers...... and wind farm transformers, and to develop a methodology on how to select appropriate equipment for the power system, control system and protection system....

  17. Incremental wind tunnel testing of high lift systems

    Science.gov (United States)

    Victor, Pricop Mihai; Mircea, Boscoianu; Daniel-Eugeniu, Crunteanu

    2016-06-01

    Efficiency of trailing edge high lift systems is essential for long range future transport aircrafts evolving in the direction of laminar wings, because they have to compensate for the low performance of the leading edge devices. Modern high lift systems are subject of high performance requirements and constrained to simple actuation, combined with a reduced number of aerodynamic elements. Passive or active flow control is thus required for the performance enhancement. An experimental investigation of reduced kinematics flap combined with passive flow control took place in a low speed wind tunnel. The most important features of the experimental setup are the relatively large size, corresponding to a Reynolds number of about 2 Million, the sweep angle of 30 degrees corresponding to long range airliners with high sweep angle wings and the large number of flap settings and mechanical vortex generators. The model description, flap settings, methodology and results are presented.

  18. Electricity for Road Transport, Flexible Power Systems and Wind Power

    DEFF Research Database (Denmark)

    Nielsen, Lars Henrik; Ravn, Hans; Meibom, Peter;

    -vehicle connection systems including technical regulation options and analysis of needs for standardisation. 4: Setting up scenarios covering potential developments for utilizing electric drive trains in road transport. Period: Up to year 2030. 5: Analysis of capacity constraints in the electricity grid...... (transmission and distribution) as consequence of increasing electricity demand, and new flexible consumption patterns from segments in the transport sector, and as consequence of increasing capacity on wind power in the system. 6: Setting up and analysis of combined scenarios covering both the heat and power......The aim of the project is to analyse the potential synergistic interplay that may arise between the power sector and the transport sector, if parts of the road transport energy needs are based on electricity via the utilisation of plug-in hybrid electric vehicles and pure electric vehicles...

  19. Wind Characteristics and development of wind forecasting at straits of Gibraltar; Caracterizacion del regimen de vientos y desarrollo de un modelo de prediccion eolica a escala local en el estrecho de Gibraltar

    Energy Technology Data Exchange (ETDEWEB)

    Palomares Losada, A. M.

    2003-07-01

    The straits of gibraltar is a privileged zone for the exploitation of the wind energy, and in a broad sense, its general wind regime is known. Nevertheless, in this zone, a special phenomenon takes place, in with the both effect of the synoptic weather systems and the peculiar orography of the straits, surrounded by two mountain chains, gives place to these wind characteristics, in which the behaviour of e and w winds is totally different in order to study this wind characteristics, two years of 10 minutes averages data,have been analysed evaluating not only the general wind regime (wind roses, weibull distributions, etc.) but also more details of the main differences between the e and w winds, as the different daily evolutions some possible explanations based on this peculiar orography are given for the obtained results. (Author) 104 refs.

  20. Space-time wind speed forecasting for improved power system dispatch

    KAUST Repository

    Zhu, Xinxin

    2014-02-27

    To support large-scale integration of wind power into electric energy systems, state-of-the-art wind speed forecasting methods should be able to provide accurate and adequate information to enable efficient, reliable, and cost-effective scheduling of wind power. Here, we incorporate space-time wind forecasts into electric power system scheduling. First, we propose a modified regime-switching, space-time wind speed forecasting model that allows the forecast regimes to vary with the dominant wind direction and with the seasons, hence avoiding a subjective choice of regimes. Then, results from the wind forecasts are incorporated into a power system economic dispatch model, the cost of which is used as a loss measure of the quality of the forecast models. This, in turn, leads to cost-effective scheduling of system-wide wind generation. Potential economic benefits arise from the system-wide generation of cost savings and from the ancillary service cost savings. We illustrate the economic benefits using a test system in the northwest region of the United States. Compared with persistence and autoregressive models, our model suggests that cost savings from integration of wind power could be on the scale of tens of millions of dollars annually in regions with high wind penetration, such as Texas and the Pacific northwest. © 2014 Sociedad de Estadística e Investigación Operativa.