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Book Analysis of Wind Turbine Blade Vibration and Drivetrain Loads

Download or read book Analysis of Wind Turbine Blade Vibration and Drivetrain Loads written by Venkatanarayanan Ramakrishnan and published by . This book was released on 2017 with total page 142 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Book Vibration Based Condition Monitoring of Wind Turbines

Download or read book Vibration Based Condition Monitoring of Wind Turbines written by Tomasz Barszcz and published by Springer. This book was released on 2018-12-04 with total page 233 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book describes in detail different types of vibration signals and the signal processing methods, including signal resampling and signal envelope, used for condition monitoring of drivetrains. A special emphasis is placed on wind turbines and on the fact that they work in highly varying operational conditions. The core of the book is devoted to cutting-edge methods used to validate and process vibration data in these conditions. Key case studies, where advanced signal processing methods are used to detect failures of gearboxes and bearings of wind turbines, are described and discussed in detail. Vibration sensors, SCADA (Supervisory Control and Data Acquisition), portable data analyzers and online condition monitoring systems, are also covered. This book offers a timely guide to both researchers and professionals working with wind turbines (but also other machines), and to graduate students willing to extend their knowledge in the field of vibration analysis.

Book Dynamics and Vibration Analyses of Gearbox in Wind Turbine

Download or read book Dynamics and Vibration Analyses of Gearbox in Wind Turbine written by Qingkai Han and published by Springer. This book was released on 2016-09-27 with total page 168 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book explores the dynamics and vibration properties of gearboxes, with a focus on geared rotor systems. It discusses mechanical theories, finite-element based simulations, experimental measurements and vibration signal processing techniques. It introduces the vibration-resonance calculation method for the geared rotor system in wind turbines and load sharing of the planetary gear train, and offers a method for calculating the vibrations of geared rotor systems under either internal excitations from gear sets or external loads transferred from wind loads. It also defines and elaborates on parameter optimization for planetary gear systems based on the torsional dynamics of wind-turbine geared rotor systems. Moreover, it describes experimental measurements of vibrations on the wind-turbine gearbox performed on the test rig and on site, and analyzes the vibration signals of different testing points, showing them in both time and frequency domains. Lastly, it lists the gear coupling frequencies and fault characteristic frequencies from the vibrations of the gearbox housing. The technologies and results presented are valuable resources for use in dynamic design, vibration prediction and analysis of gearboxes and geared rotor systems in wind turbines as well as many other machines.

Book Structural Analysis of Composite Wind Turbine Blades

Download or read book Structural Analysis of Composite Wind Turbine Blades written by Dimitris I Chortis and published by Springer Science & Business Media. This book was released on 2013-06-29 with total page 240 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book concerns the development of novel finite elements for the structural analysis of composite beams and blades. The introduction of material damping is also an important aspect of composite structures and it is presented here in terms of their static and dynamic behavior. The book thoroughly presents a new shear beam finite element, which entails new blade section mechanics, capable of predicting structural blade coupling due to composite coupling and/or internal section geometry. Theoretical background is further expanded towards the inclusion of nonlinear structural blade models and damping mechanics for composite structures. The models effectively include geometrically nonlinear terms due to large displacements and rotations, improve the modeling accuracy of very large flexible blades, and enable the modeling of rotational stiffening and buckling, as well as, nonlinear structural coupling. Validation simulations on specimen level study the geometric nonlinearities effect on the modal frequencies and damping values of composite strips of various angle-ply laminations under either tensile or buckling loading. A series of correlation cases between numerical predictions and experimental measurements give credence to the developed nonlinear beam finite element models and underline the essential role of new nonlinear damping and stiffness terms.

Book Modeling and Modern Control of Wind Power

Download or read book Modeling and Modern Control of Wind Power written by Qiuwei Wu and published by John Wiley & Sons. This book was released on 2018-02-05 with total page 281 pages. Available in PDF, EPUB and Kindle. Book excerpt: An essential reference to the modeling techniques of wind turbine systems for the application of advanced control methods This book covers the modeling of wind power and application of modern control methods to the wind power control—specifically the models of type 3 and type 4 wind turbines. The modeling aspects will help readers to streamline the wind turbine and wind power plant modeling, and reduce the burden of power system simulations to investigate the impact of wind power on power systems. The use of modern control methods will help technology development, especially from the perspective of manufactures. Chapter coverage includes: status of wind power development, grid code requirements for wind power integration; modeling and control of doubly fed induction generator (DFIG) wind turbine generator (WTG); optimal control strategy for load reduction of full scale converter (FSC) WTG; clustering based WTG model linearization; adaptive control of wind turbines for maximum power point tracking (MPPT); distributed model predictive active power control of wind power plants and energy storage systems; model predictive voltage control of wind power plants; control of wind power plant clusters; and fault ride-through capability enhancement of VSC HVDC connected offshore wind power plants. Modeling and Modern Control of Wind Power also features tables, illustrations, case studies, and an appendix showing a selection of typical test systems and the code of adaptive and distributed model predictive control. Analyzes the developments in control methods for wind turbines (focusing on type 3 and type 4 wind turbines) Provides an overview of the latest changes in grid code requirements for wind power integration Reviews the operation characteristics of the FSC and DFIG WTG Presents production efficiency improvement of WTG under uncertainties and disturbances with adaptive control Deals with model predictive active and reactive power control of wind power plants Describes enhanced control of VSC HVDC connected offshore wind power plants Modeling and Modern Control of Wind Power is ideal for PhD students and researchers studying the field, but is also highly beneficial to engineers and transmission system operators (TSOs), wind turbine manufacturers, and consulting companies.

Book Development of a Wind Turbine Condition Monitoring Facility for Drivetrain Torsional Dynamics Investigations

Download or read book Development of a Wind Turbine Condition Monitoring Facility for Drivetrain Torsional Dynamics Investigations written by Paul Van Niekerk and published by . This book was released on 2018 with total page 198 pages. Available in PDF, EPUB and Kindle. Book excerpt: Maintenance can be performed according to one of two strategies, failure based or condition based. In most cases, where large and expensive assets such as wind turbines are operated on a continuous basis, condition based maintenance is preferred. However, condition based maintenance relies on the continuous and accurate gathering of condition-information of the particular machine and its various components. This dissertation reports the experimental and numerical work performed as part of the development of an experimental facility that will allow the development of condition monitoring techniques for wind turbines. This work is focussed on the torsional dynamics of a wind turbine setup. A physical setup, consisting of a 1.6 m diameter turbine, a 1:1. ̇ speed-multiplication gearbox, and a 24 Volt direct current generator is built. All of it is mounted within an open-return wind tunnel, which is also designed and built as part of this work. The following two cost-effective experimental techniques are used to measure the torsional natural frequencies: a shaft encoder tachometer from which instantaneous rotational frequency is obtained, and power signal analysis, where the generated voltage is recorded and analysed. It is shown how an algorithm developed by Diamond et al. (2016) is used for the shaft encoder geometry compensation. Frequency spectra based on Fourier transforms and short time Fourier transforms are used to identify harmonic frequencies. Both measurement techniques proves useful to identify not only natural frequencies of torsional vibration, but also various characteristic frequencies of the drivetrain such as shaft rotation, blade pass, gear mesh and generator armature. It is found that power signal analysis is more useful to identify the characteristic frequencies. Torsional dynamics of the drivetrain and its components are also investigated with the following two numerical methods: an eight-degree-of-freedom torsional Lumped Mass Model (LMM), and a three-dimensional Finite Element Model (FEM). Torsional mode shapes and frequencies are calculated with both methods and a good agreement is found in the lower four modes. Numerical results are then compared with the experimental results, where there is also good agreement in the lower four modes. Model updating is performed on the FEM and by changing the torsional stiffness of the flexible couplings, the difference between measured and calculated natural frequencies are reduced to less than 6 %. It is concluded that future models should address lateral vibration of the drivetrain and the support structure. From this study the following is contributed to the wind turbine condition monitoring field: considerations for the design and a working example of an experimental facility for investigating torsional dynamics, illustration of two measurement techniques, and two types of validated numerical models.

Book Offshore Wind Energy Technology

Download or read book Offshore Wind Energy Technology written by Olimpo Anaya-Lara and published by John Wiley & Sons. This book was released on 2018-05-11 with total page 459 pages. Available in PDF, EPUB and Kindle. Book excerpt: A COMPREHENSIVE REFERENCE TO THE MOST RECENT ADVANCEMENTS IN OFFSHORE WIND TECHNOLOGY Offshore Wind Energy Technology offers a reference based on the research material developed by the acclaimed Norwegian Research Centre for Offshore Wind Technology (NOWITECH) and material developed by the expert authors over the last 20 years. This comprehensive text covers critical topics such as wind energy conversion systems technology, control systems, grid connection and system integration, and novel structures including bottom-fixed and floating. The text also reviews the most current operation and maintenance strategies as well as technologies and design tools for novel offshore wind energy concepts. The text contains a wealth of mathematical derivations, tables, graphs, worked examples, and illustrative case studies. Authoritative and accessible, Offshore Wind Energy Technology: Contains coverage of electricity markets for offshore wind energy and then discusses the challenges posed by the cost and limited opportunities Discusses novel offshore wind turbine structures and floaters Features an analysis of the stochastic dynamics of offshore/marine structures Describes the logistics of planning, designing, building, and connecting an offshore wind farm Written for students and professionals in the field, Offshore Wind Energy Technology is a definitive resource that reviews all facets of offshore wind energy technology and grid connection.

Book Vibration Analysis and Optimisation of a Wind Turbine Blade

Download or read book Vibration Analysis and Optimisation of a Wind Turbine Blade written by and published by . This book was released on 2010 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:

Book MARE WINT

Download or read book MARE WINT written by Wiesław Ostachowicz and published by Springer. This book was released on 2016-08-30 with total page 432 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book provides a holistic, interdisciplinary overview of offshore wind energy, and is a must-read for advanced researchers. Topics, from the design and analysis of future turbines, to the decommissioning of wind farms, are covered. The scope of the work ranges from analytical, numerical and experimental advancements in structural and fluid mechanics, to novel developments in risk, safety & reliability engineering for offshore wind.The core objective of the current work is to make offshore wind energy more competitive, by improving the reliability, and operations and maintenance (O&M) strategies of wind turbines. The research was carried out under the auspices of the EU-funded project, MARE-WINT. The project provided a unique opportunity for a group of researchers to work closely together, undergo multidisciplinary doctoral training, and conduct research in the area of offshore wind energy generation. Contributions from expert, external authors are also included, and the complete work seeks to bridge the gap between research and a rapidly-evolving industry.

Book Advances in wind turbine blade design and materials

Download or read book Advances in wind turbine blade design and materials written by J. G.Holierhoek and published by Elsevier Inc. Chapters. This book was released on 2013-10-31 with total page 30 pages. Available in PDF, EPUB and Kindle. Book excerpt: Aeroelasticity concerns the interaction between aerodynamics, dynamics and elasticity. This interaction can result in negatively or badly damped wind turbine blade modes, which can have a significant effect on the turbine lifetime. The first aeroelastic problem that occurred on commercial wind turbines concerned a negatively damped edgewise mode. It is important to ensure that there is some out-of-plane deformation in this mode shape to prevent the instability. For larger turbine blades with lower torsional stiffness and the possibility of higher tip speeds for the offshore designs, classical flutter could also become relevant. When designing a wind turbine blade, it is therefore crucial that there is enough damping for the different modes and that there is no coincidence of natural frequencies with excitation frequencies (resonance). An effective aeroelastic analysis is also important, and the tools used for such an analysis must include the necessary detail in the structural model.

Book Mechanics and Vibration Modeling of Vertical axis Wind turbine Blades and Analysis of Systems with Parametric Excitation

Download or read book Mechanics and Vibration Modeling of Vertical axis Wind turbine Blades and Analysis of Systems with Parametric Excitation written by Fatemeh Afzali and published by . This book was released on 2023 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Wind turbines are one of the fastest-growing energy sources. Based on their axis of rotation they fall into two basic categories: horizontal-axis wind turbines (HAWTs) and vertical-axis wind turbines (VAWTs). Darrieus VAWTs exploit aerodynamic lift. This study entails the vibration analysis of large vertical-axis Darrieus wind turbine blades. Very large wind turbines are becoming more abundant due to their ability to harvest greater wind power. VAWTs are less common than HAWTs for large wind applications, but have some favorable characteristics, for example in offshore applications, and so further development of large VAWTs is anticipated. However, VAWTs are known to have vibration issues. VAWT blade vibration is the focus of this work.The straight-bladed H-rotor/Giromill is the simplest type of VAWT. We first derive the equations of motion of a H-rotor blade modeled as a uniform straight elastic Euler-Bernoulli beam under transverse bending and twist deformation. The reduced-order model suggests the existence of periodic damping, periodic stiffness, and direct excitation generated by a cyclic aeroelastic load. The model also indicates spin softening, which could be detrimental as the turbines become large. Periodic damping and stiffness are examples of parametric excitation and are likely to carry over to other types of VAWT blades. Systems with parametric excitation have been studied with various methods. Floquet theory has been classically used to study the stability characteristics of linear systems with periodic coefficients, and has been commonly applied to Mathieu's equation, which represents a vibration system with periodic stiffness. We apply the Floquet theory combined with the harmonic-balance method to a linear vibration system with a periodic damping coefficient. Based on this theory, the approximated solution includes an exponential part, with an unknown exponent, and a periodic part. Our analysis investigates the initial conditions response, the boundaries of instability, and the characteristics of free response solution of the system. The coexistence phenomenon, in which some of the transition curves overlap so that the instability wedges disappear, is recovered in this approach, and is examined closely.An additional case of the parametric excitation is the combination of parametric damping and parametric stiffness. The Floquet-based analysis shows that the combined parametric excitation reshapes the stability characteristics, compared to the system with only parametric damping or stiffness and disrupts the coexistence which is observed in the parametric damping case.The aeroelastic forces encountered by the wind turbines can cause self-excitation in blades, the mechanism of which can be loosely modeled with van-der-Pol-type nonlinearity. We seek to understand the combined effect of parametric excitation and van der Pol nonlinearity, as both can induce instabilities and oscillations. The oscillator is studied under nonresonant conditions and secondary resonances, with and without external excitation. We analyze the system using the method of multiple scales and numerical solutions. For the case without external excitation, the analysis reveals nonresonant phase drift (quasi-periodic responses), and subharmonic resonance with possible phase drift or phase locking (periodic responses). Hard excitation is treated for nonresonant conditions and secondary resonances, and similar phenomena are uncovered.Some Darrieus VAWTs consist of curved blades. We lastly study the modal analysis of curved Darrieus wind-turbine blades and obtain the mode shapes and modal frequencies. The governing equations are derived using the fundamental deformation mechanics, and thin beam approximations are employed to express the strain and kinetic energies. The assumed-modes method is applied to the energies, and the Euler-Lagrange equation is used to discretize the equations of motion. Implementing these equations, mode shapes are calculated and mapped back onto the curved beam for visualization. This analysis is conducted for pinned-pinned and hinged-hinged blades. The results are compared with Finite element analysis using Abaqus and with the literature.

Book Nonlinear Composite Beam Theory

Download or read book Nonlinear Composite Beam Theory written by Dewey H. Hodges and published by Progress in Astronautics and A. This book was released on 2006 with total page 344 pages. Available in PDF, EPUB and Kindle. Book excerpt: From an authoritative expert whose work on modern helicopter rotor blade analysis has spanned over three decades, comes the first consistent and rigorous presentation of beam theory. Beginning with an overview of the theory developed over the last 60 years, Dr. Hodges addresses the kinematics of beam deformation, provides a simple way to characterize strain in an initially curved and twisted beam, and offers cross-sectional analysis for beams with arbitrary cross sections and composed of arbitrary materials. He goes on to present a way to accurately recover all components of cross-sectional strain and stress before providing a natural one-dimensional (1-D) theory of beams. Sample results for both cross-sectional and 1-D analysis are presented as is a parallel treatment for thin-walled beams.

Book NASA Technical Memorandum

Download or read book NASA Technical Memorandum written by and published by . This book was released on 1984 with total page 82 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Book Advances in Nonlinear Dynamics

Download or read book Advances in Nonlinear Dynamics written by Walter Lacarbonara and published by Springer Nature. This book was released on 2022-03-18 with total page 891 pages. Available in PDF, EPUB and Kindle. Book excerpt: This first of three volumes includes papers from the second series of NODYCON, which was held virtually in February of 2021. The conference papers reflect a broad coverage of topics in nonlinear dynamics, ranging from traditional topics from established streams of research to those from relatively unexplored and emerging venues of research. These include Fluid-structure interactions Mechanical systems and structures Computational nonlinear dynamics Analytical techniques Bifurcation and dynamic instability Rotating systems Modal interactions and energy transfer Nonsmooth systems

Book Advances in wind turbine blade design and materials

Download or read book Advances in wind turbine blade design and materials written by H. Söker and published by Elsevier Inc. Chapters. This book was released on 2013-10-31 with total page 36 pages. Available in PDF, EPUB and Kindle. Book excerpt: This chapter deals with loads on wind turbine blades. It describes the load generating process, wind fields, and the concepts of stresses and strains. Aerodynamic loads, loads introduced by inertia, gravitation and gyroscopic effects, and actuation loads are discussed. The loading effects on the rotor blades and how they are interconnected with the dynamics of the turbine structure are highlighted. There is a discussion on how stochastic loads can be analysed and an outline of cycle counting methodology. The method of design verification testing is briefly described.