Active Load Control Techniques for Wind Turbines Focusing on Mechanical Design of a Microtab System

Active Load Control Techniques for Wind Turbines Focusing on Mechanical Design of a Microtab System PDF Author: Scott Jeremy Johnson
Publisher:
ISBN:
Category :
Languages : en
Pages : 338

Book Description


Final Report 02-ERD-056 Active Load Control & Mitigation Using Microtabs

Final Report 02-ERD-056 Active Load Control & Mitigation Using Microtabs PDF Author:
Publisher:
ISBN:
Category :
Languages : en
Pages : 43

Book Description
With public concern over the security and reliability of our existing electricity infrastructure and the resurgence of wind energy, the wind industry offers an immediate, first point of entry for the application and demonstration of an active load control technology. An innovative microtab approach is being investigated and demonstrated for active aerodynamic load control applications under the mid-year LDRD (June-Sept. 2002) effort. With many of these million dollar turbines failing at only half the design lifespans, conventional techniques for stiffening rotors, enlarging generators and gearboxes, and reinforcing towers are insufficient to accommodate the demands for bigger, taller and more powerful turbines. The DOE through the National Renewable Energy Laboratory (NREL) supports R & D efforts to develop lighter, more efficient and longer lasting wind turbines and advance turbine components. However, as wind turbine systems continue to increase in size and complexity, fundamental research and technology development has not kept pace with needs. New technologies to increase turbine life spans and to reduce costs are needed to realize wind electricity generation potentials. It is becoming quite evident that without a better understanding of static and dynamic response to normal and abnormal operating loads coupled with sophisticated flow analysis and control techniques, large turbine operating life and component life will be severely limited. Promising technologies include active load control and load alleviation systems to mitigate peak loads from damaging key components. This project addresses science and engineering challenges of developing enabling technologies for active load control for turbine applications using an innovative, translational microtab approach. Figure 1.1 illustrates the microtabs as applied on a wind turbine system. Extending wind turbine operating life is a crucial component for reducing the cost of wind-generated electricity, enabling wind energy market penetration and improving the reliability of the nation's renewable electrical generation infrastructure. This project also provides enabling technologies for improving turbine efficiency and durability to support the DOE and NNSA missions of providing energy security and reliability without contributing to greenhouse gas emissions and for decreasing dependence on foreign fuel sources. In addition to wind generator applications, the realization of a ''smart'' controllable structure for load control using the microtab approach has the potential to revolutionize design of other complex systems. Driven by cost and safety, both passive and active flow control for steady and unsteady conditions have been actively investigated by NASA, DARPA, DOE and other research institutions for application on rotorcraft, UAVs, marine vessels and wind turbine applications. The potential to obtain revolutionary advances in aerodynamic hydrodynamic performance, safety, maneuverability and service life by decreasing loads is an attractive prospect across many industries.

Modeling and Modern Control of Wind Power

Modeling and Modern Control of Wind Power PDF Author: Qiuwei Wu
Publisher: John Wiley & Sons
ISBN: 1119236398
Category : Science
Languages : en
Pages : 373

Book Description
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.

Active Load Control Techniques for Wind Turbines

Active Load Control Techniques for Wind Turbines PDF Author:
Publisher:
ISBN:
Category :
Languages : en
Pages : 132

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

Control Techniques For Wind Energy Conversion System

Control Techniques For Wind Energy Conversion System PDF Author: Subhashree Priyadarshini, Rosalin Pradhan & Bibhu Prasad Ganthia
Publisher: BFC Publications
ISBN: 9391455530
Category : Juvenile Nonfiction
Languages : en
Pages : 62

Book Description
The interests towards renewable energy enhance its demand due to zero pollutant emission. Considering present scenario wind as renewable source of energy is highly recommended. As it is freely available and free from pollution, this wind can be effectively play highly potential role for energy generations. This can produce quality power during grid integrations as the load demands. Due to rapid variations in wind speed wind energy system needs highly synchronized and powerful controller techniques for power regulations to overcome transients, voltage sags and swells. A suitable and fast responsive controller is essential for power generation from wind energy. The controllers for wind energy system categorized into five controller designs according to its locations to control the demand of the turbine system during grid integrations. In this book various controller designs and its implementations are highlighted with reference to previous works and existing researches. This book emphasizes overall strategies for various controllers for wind energy conversion system and establishes ideas for the researcher for their novel works.

Load Reducing Control for Wind Turbines

Load Reducing Control for Wind Turbines PDF Author: Martin Shan
Publisher: Fraunhofer Verlag
ISBN: 9783839613696
Category : Technology & Engineering
Languages : en
Pages : 0

Book Description
In wind turbine engineering, it is a well-known fact that mechanical loading of the structural components, as tower and blades, can be heavily influenced by means of control. This work provides a comprehensive discussion on systematic control design for active load reduction. A review of the established approaches for load reducing pitch control is given. The basic idea is to adjust the blade pitch angles to provide active damping of structural loads or to compensate for periodic load components. A survey on rating and cost of wind turbine structural components is given to sketch the potential impacts of control design on Cost-of-Energy. Special focus in a separate chapter is given to the major trade-off between load reductions and rating of the pitch actuator system. In the main part, a pragmatic approach to systematic control design by use of modern multi-variable control design methods is introduced. Linear models in combination with disturbance spectra are applied to allow for fast and transparent optimization of the controllers. Exemplarily, this hierarchical control design / controller tuning approach is demonstrated for two different types of load reducing pitch controllers.

Wind Turbine Control Systems

Wind Turbine Control Systems PDF Author: Fernando D. Bianchi
Publisher: Springer Science & Business Media
ISBN: 1846284937
Category : Technology & Engineering
Languages : en
Pages : 219

Book Description
This book emphasizes the application of Linear Parameter Varying (LPV) gain scheduling techniques to the control of wind energy conversion systems. This reformulation of the classical problem of gain scheduling allows straightforward design procedure and simple controller implementation. From an overview of basic wind energy conversion, to analysis of common control strategies, to design details for LPV gain-scheduled controllers for both fixed- and variable-pitch, this is a thorough and informative monograph.

Active Load Control Using Microtabs

Active Load Control Using Microtabs PDF Author: Dora Te-Lun Yen
Publisher:
ISBN:
Category :
Languages : en
Pages : 284

Book Description


Mechanical Design and Load Estimation Methods for Advanced Wind Turbines

Mechanical Design and Load Estimation Methods for Advanced Wind Turbines PDF Author: Kevin Lee Jackson
Publisher:
ISBN:
Category :
Languages : en
Pages : 326

Book Description


Wind Tunnel Testing of Microtabs and Microjets for Active Load Control of Wind Turbine Blades

Wind Tunnel Testing of Microtabs and Microjets for Active Load Control of Wind Turbine Blades PDF Author: Aubryn Murray Cooperman
Publisher:
ISBN: 9781267967886
Category :
Languages : en
Pages :

Book Description
Increases in wind turbine size have made controlling loads on the blades an important consideration for future turbine designs. One approach that could reduce extreme loads and minimize load variation is to incorporate active control devices into the blades that are able to change the aerodynamic forces acting on the turbine. A wind tunnel model has been constructed to allow testing of different active aerodynamic load control devices. Two such devices have been tested in the UC Davis Aeronautical Wind Tunnel: microtabs and microjets. Microtabs are small surfaces oriented perpendicular to an airfoil surface that can be deployed and retracted to alter the lift coefficient of the airfoil. Microjets produce similar effects using air blown perpendicular to the airfoil surface. Results are presented here for both static and dynamic performance of the two devices. Microtabs, located at 95% chord on the lower surface and 90% chord on the upper surface, with a height of 1% chord, produce a change in the lift coefficient of 0.18, increasing lift when deployed on the lower surface and decreasing lift when deployed on the upper surface. Microjets with a momentum coefficient of 0.006 at the same locations produce a change in the lift coefficient of 0.19. The activation time for both devices is less than 0.3 s, which is rapid compared to typical gust rise times.The potential of active device to mitigate changes in loads was tested using simulated gusts. The gusts were produced in the wind tunnel by accelerating the test section air speed at rates of up to 7 ft/s2. Open-loop control of microtabs was tested in two modes: simultaneous and sequential tab deployment. Activating all tabs along the model span simultaneously was found to produce a change in the loads that occurred more rapidly than a gust. Sequential tab deployment more closely matched the rates of change due to gusts and tab deployment. A closed-loop control system was developed for the microtabs using a simple feedback control based on lift measurements from a six-component balance. An alternative input to the control system that would be easier to implement on a turbine was also investigated: the lift force was estimated using the difference in surface pressure at 15% chord. Both control system approaches were found to decrease lift deviations by around 50% during rapid changes in the free stream air speed.