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Today’s wind power plants are only compensated for their reactive power consumption at no-load. As the wind power plants grow bigger the amount of reactive power they need also increases. This is no longer a problem that can be ignored, especially as the net owners are beginning …
Today’s wind power plants are only compensated for their reactive power consumption at no-load. As the wind power plants grow bigger the amount of reactive power they need also increases. This is no longer a problem that can be ignored, especially as the net owners are beginning …
ABSTRACT Many wind turbines have problems with icing and there is still no effective method to de-ice without stoppage of production and power loss. Here I therefore consider other methods than those available today, and particularly, I consider how these methods could be …
… 8 shows the difficulties when the measurement is unprotected from the wind. With small resistance, as in an energy efficient vehicle like Elba, the measurement is more sensitive to disturbances. This causes the need of preprocessing data before the calculations are done. The …
… around finding better ways of overseeing vibrations of the gearbox at a wind power station. The gearbox has been a huge problem at the stations located at Gässlingen and the sooner the warning of an incoming breakdown is at hand the more money you can save from preparations. The …
The project contains a force analysis of the vertical axis wind turbine Lucia's supporting arms and a measuring device to experimentally measure the forces is made. The forces between the supporting arms and the tower are calculated theoretically and then simulated by a …
… they affect the stand on behalf of future growth, theoretical economic result, wind impact, snow pressure and density of stand. The investigation is regarding the first commercial thinning of pine stands, after pre-commercial thinning that was well conducted. The investigation …
en studie i norra Island
… of papers and books. Correlations were made comparing tetratherm against the wind speed, height above sea level and distance to the sea. The parameters explained 74 % of the variation of the tetratherm. Therefore would it be interesting to further develop the tetratherm model by …
en ekonomisk analys
… of the problem. A lot of forest owners got large areas of spruce stands wind thrown during this storm. Can naturally regenerated birch (Betula sp.) be an alternative on these wind-exposed sites? This was the main question I was facing when discussilig the problems with Esben …
… aims at solving this shortage by the construction of a long carbon fiber wind tunnel in which real measurements can be made. To do accurate measurements it is of importance that the wind tunnel, 0.9 meters in diameter and 110 meters long, is as straight as possible. This master …
… parts compared with the southern parts. This could be an effect of the wind direction, and will still cause variations.
… as coasters for the piles, or that the numbers had been erased by weather and wind. There is also a possibility that the missing logs had been left on the site. Possible source of error can be that the forwarder operators paid the marked logs some extra attention. They claimed …
… friction velocities above 0.4 m/s. There appeared four distinctly different wind direction sectors that showed significantly different respiration levels. These sectors were weakly correlated to differences in stand properties. A PLS-model for the carbon flux was created with …
… climate parameters (air temperature, globe temperature, relative humidity, wind angle and wind speed and solar radiation) were recorded in a weather-station. Inside the barn air temperature and relative humidity were recorded. The study also collected parameters reflecting the …
jämförelse mellan naturlig och mekanisk ventilation
… is based on the temperature difference between the external and internal air, wind speed and, most crucially, the speed of the vehicle itself. It thus varies considerably. Mechanical fans can be mounted inside to provide a more even ventilation effect and to guarantee that the …
