Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Optimising the control of wind generators by means of intelligent microsensors

25.04.2006


The School of Engineering at Bayonne (ESTIA) is working on a research project on control optimisation for the latest-generation wind generators using intelligent microsensors.



The latest-generation wind generators work at variable speed and with pitch regulation based on the pitch angle of the rotor blades. These degrees of freedom (the rotation speed and the pitch angle of each blade) enable an increase in energy yield, a decrease in fatigue due to mechanical loads and an enhancement in the quality of the electrical potential with respect to fixed-speed wind turbines. The rotation speed and the pitch angle of the blades are controlled continuously by control algorithms and the quality of these algorithms have a determining influence on the price of the energy produced by the wind generators. Although a large amount of research work on wind generator control has been undertaken, it still remains for more “intelligence” to be introduced into their functioning.

The reduction in the price of wind energy is made possible through:


- increasing the reliability and robustness of wind generators
- increasing the energy yield
- manufacturing lighter wind generators.

This weight reduction can be achieved only by reducing the mechanical forces on the blades, the transmission axle and the tower. Moreover, the current trend in increasing the size of wind generators means having mechanically more flexible machines. The control has to take into account this flexibility, especially avoiding the resonance frequencies of the various mechanical elements.

Thus, the classical criteria linked to the optimisation of control algorithms for variable-speed and pitch-regulated wind generators are:

- the quality of the electrical potential produced
- the reduction in the dynamic loads to which the wind generator structure is subjected
- the energy yield
- the robustness of the control algorithms developed.

Within the framework of this question, the ESTIA School of Engineering is particularly focusing on criteria dealing with the reduction of the mechanical stresses arising from fatigue in the elements of a wind generator (tower, blades, transmission axle/gearbox).

Fatigue in a wind generator’s elements is mainly linked with the external dynamic forces that these parts undergo and with the fluctuations in their resonance frequencies. Control of the wind generator should enable an overall reduction in these stresses in order to increase reliability and, thereby, the usefulness of wind generators, and enable a reduction in the overall weight of their components. The main loads are those withstood by the blades, the tower and the transmission axle/gearbox. The design of the control algorithms has to take into account this reduction in the mechanical stresses in these components. Several degrees of freedom exist in order to achieve this target: the two of the electric motor, the pitch angle for each blade (three for the classical wind generator) and the orientation (the “yaw”) of the whole turbine with respect to the tower axis. This last parameter is not within the remit of this current research project.

The design of this control should take into account not just one of the four criteria previously mentioned. Although the main objective here is the reduction of dynamic stresses experienced by the wind generator, the other criteria are not forgotten.

Intelligent microsensors (acceleration sensors with wireless communication) located at the blade tips, above the surface of the wind generator axis and in the tower will be used to optimise the control.

Thanks to these acceleration sensors, the control system will have supplementary information in real time, thus enabling reduction in fatigue stresses using multivariable optimisation algorithms.

Commercial wind generators are fitted with a number of sensors (voltage, current, rotation velocity, etc.). Nevertheless, they are currently not fitted with acceleration or with stress sensors.

Irati Kortabitarte | alfa
Further information:
http://www.basqueresearch.com/berria_irakurri.asp?Gelaxka=1_1&hizk=I&Berri_Kod=951

More articles from Power and Electrical Engineering:

nachricht How protons move through a fuel cell
22.06.2017 | Empa - Eidgenössische Materialprüfungs- und Forschungsanstalt

nachricht Fraunhofer IZFP acquires lucrative EU project for increasing nuclear power plant safety
21.06.2017 | Fraunhofer-Institut für Zerstörungsfreie Prüfverfahren IZFP

All articles from Power and Electrical Engineering >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Can we see monkeys from space? Emerging technologies to map biodiversity

An international team of scientists has proposed a new multi-disciplinary approach in which an array of new technologies will allow us to map biodiversity and the risks that wildlife is facing at the scale of whole landscapes. The findings are published in Nature Ecology and Evolution. This international research is led by the Kunming Institute of Zoology from China, University of East Anglia, University of Leicester and the Leibniz Institute for Zoo and Wildlife Research.

Using a combination of satellite and ground data, the team proposes that it is now possible to map biodiversity with an accuracy that has not been previously...

Im Focus: Climate satellite: Tracking methane with robust laser technology

Heatwaves in the Arctic, longer periods of vegetation in Europe, severe floods in West Africa – starting in 2021, scientists want to explore the emissions of the greenhouse gas methane with the German-French satellite MERLIN. This is made possible by a new robust laser system of the Fraunhofer Institute for Laser Technology ILT in Aachen, which achieves unprecedented measurement accuracy.

Methane is primarily the result of the decomposition of organic matter. The gas has a 25 times greater warming potential than carbon dioxide, but is not as...

Im Focus: How protons move through a fuel cell

Hydrogen is regarded as the energy source of the future: It is produced with solar power and can be used to generate heat and electricity in fuel cells. Empa researchers have now succeeded in decoding the movement of hydrogen ions in crystals – a key step towards more efficient energy conversion in the hydrogen industry of tomorrow.

As charge carriers, electrons and ions play the leading role in electrochemical energy storage devices and converters such as batteries and fuel cells. Proton...

Im Focus: A unique data centre for cosmological simulations

Scientists from the Excellence Cluster Universe at the Ludwig-Maximilians-Universität Munich have establised "Cosmowebportal", a unique data centre for cosmological simulations located at the Leibniz Supercomputing Centre (LRZ) of the Bavarian Academy of Sciences. The complete results of a series of large hydrodynamical cosmological simulations are available, with data volumes typically exceeding several hundred terabytes. Scientists worldwide can interactively explore these complex simulations via a web interface and directly access the results.

With current telescopes, scientists can observe our Universe’s galaxies and galaxy clusters and their distribution along an invisible cosmic web. From the...

Im Focus: Scientists develop molecular thermometer for contactless measurement using infrared light

Temperature measurements possible even on the smallest scale / Molecular ruby for use in material sciences, biology, and medicine

Chemists at Johannes Gutenberg University Mainz (JGU) in cooperation with researchers of the German Federal Institute for Materials Research and Testing (BAM)...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Plants are networkers

19.06.2017 | Event News

Digital Survival Training for Executives

13.06.2017 | Event News

Global Learning Council Summit 2017

13.06.2017 | Event News

 
Latest News

Quantum thermometer or optical refrigerator?

23.06.2017 | Physics and Astronomy

A 100-year-old physics problem has been solved at EPFL

23.06.2017 | Physics and Astronomy

Equipping form with function

23.06.2017 | Information Technology

VideoLinks
B2B-VideoLinks
More VideoLinks >>>