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676 Uppsatser om Wind load - Sida 7 av 46
Utredning av frekvensregleringens påverkan på mekanisk utrustning i en kaplanturbin
As a consequence of increasing wind power installations in the Nordic grid the last years, the need for regulating power has become larger. In the Nordic grid, regulating power is mainly provided by hydro power. One part of the regulating power is called frequency control, which ensures that the grid frequency is stable and close to 50 Hz.However, setting the turbine into frequency controlled operation may cause stress and wear of the components in the mechanical control system. Frequency controlling implies large and frequent servo forces and longer travelling distance of the sliding bearings in the Kaplan turbine.Based on one selected Kaplan turbine, Selsfors G1, measurements and MATLAB calculations have been performed in order to determine forces and movements of the linkage system. With these forces and movements as input, stresses and fatigue have been determined as well as sliding distances, bearing pressures and wear of bearings during a typical lifetime of 40 years.The results indicate that no severe wear exists on the bearings during 40 years of service.
Konstruktion av en autonom vindstation
Construction of an autonomous wind station was a project with the goal of creating a product that could collect wind data from a sensor and then transfer this data to a server wirelessly over the GSM network. The device would be powered by batteries and solar cells and function fully without requiring external power supply. This required that a small computer was constructed and programmed to store and send data at predetermined cycle times and programming of a server that received the sent data. The project also required optimization of power consumption and dimensioning of solar cells and batteries based on this. The construction of this station demanded research both for the selection of hardware and programming software. The computer was based on a microcontroller and a GSM module that sent the data over the 2G network.
Felisolering av hytt- och chassikomponenter på tunga fordon
This master of science thesis is focusing on how the fault handling on hardware connected toa control unit on a Scania vehicle is working. To the hardware counts buttons levers, sensorsand CAN. The work has been concentrated upon how the fault handling is working and if it ispossible to find any new fault modes.The control unit that has been studied is called the Coordinator and is the core in Scanias threenetworks of control units. The Coordinators work is to transmit messages between the threenetworks and to process signals from buttons, levers and sensors. The values is then usedinternally or is sent to other control units on the CAN networks.
Minivindkraftverks inverkan på lågspänningsnät
Micro-power wind energy convertors have recently increased in popularity. The reasons for this are among other things the increasing cost of electric energy and enviromental concern.In this thesis the connection of these micro-power wind energy convertors to the utility network is discussed. Electric standards for the connection of small production units is presented. Finally some calculations and measurements of electric quality are also presented. The utility network used in the calculations is part of Halmstad Energi och Miljö network..
Projektering av vindkraft i turbulensintensiva områden : med fallstudie för Wallenstams planerade park vid Skuggetorp
Along with the rapid expansion of wind power in Sweden during the last decades the competition about favorable areas has hardened. This among other reasons has caused the projectors to look into development of wind power in forests. There are several aspects regarding fatigue loads on the constructions that are severe in complex terrain, among which turbulence is one. The levels of turbulence which are accepted in order for the turbines to face a life length exceeding 20 years are regulated by the International Electrotechnical Commission, (IEC). In order to keep the turbulence below these levels there are three major steering tools to use: The ambient turbulence decreases with height and can therefore be regulated by the hub height of the turbines.
Metoder för lastprioritering i fjärrvärmecentraler
A problem in the field of district heating is the oil burners needed to provide power when a peak load occurs. One possible way of reducing the needed amount of oil is to reduce the power demand for space heating in the district-heating substations when the need for district heating water exceeds a certain limit. This can be done by use of a locally working controller function.In this Thesis the options concerning load priority are evaluated. To evaluate the potential for using controller functions concerning peak load priority an experiment was brought out in a chosen district-heating substation. The impact on the indoor thermal comfort during a heat reduction was also taken into account.
Riksintresse; Bevarande eller nyttjande : Vindkraftsutbyggnad inom Natura 2000- områden
Natura 2000 is part of the European Union: s framework to protect and preserve biological diversity. Natura 2000- areas are by the goverment appointed to areas of national interest for preserving nature. Also wind power stations are appointed as of national interest and the reason for this is the goverments goal to get energy from reneweble energysources. This essay describes when both these intrests conflict eachother when it comes to building wind power stations within Natura 2000- areas. The main focus of this essay is a casestudy of two cases from two different counties, Dalarna- and Norrbotten county, where applications have been made to build wind power stations within existing Natura 2000- ares, both cases have reached the court dealing with enviromental issues.
Näringsbelastning på en anlagd våtmark från åker, skog och enskilda avlopp :
This work is a part of the project ?Våtmarker i odlingslandskapet ? uppföljning av miljömålen? (Wetlands in arable land ? following-up of the environmental goals). The main objective with this project is to study nitrogen and phosphorus retention in a constructed wetland by using mass balance calculations. Continuous measurements of nutrients and water flow through the inlet and the outlet of the wetland are made. However, substantial amounts of nitrogen and phosphorus were assumed to reach the wetland with a drain-pipe transporting wastewater from nearby houses (10 persons).
Balansering av vindkraft och vattenkraft i norra Sverige
This master thesis was initiated with the aim to answer at what level of installed capacity of wind power in the northern parts of Sweden it would be beneficial to improve the transmission capacity from the northern Sweden. During the process of this work the aim has changed to try and create a model that can be used to analyze how well the hydro power installed in the northern Sweden can even out the quick changes in wind power production.To create a good model of all hydro power in northern Sweden is a very large job, unfortunately too large for a master thesis. This report therefore ends with an extensive analysis of the simplifications that have been made and their effects as well as a list of the future work that has to be done.The model that has been created have shown to be effective and produce good results. The conclusions that can be made is that the northern Swedish hydro power have very good possibilities to balance the wind power production. Only a few cases where water have been spilled even though there has been some free capacity has been discovered.
Beräkningsmall för vindlast enligt Eurokod baserad på väggar och olika taktyper
Detta examensarbete har genomförts på begäran av byggnadstekniska byrån i Uppsala. Företaget behöver en ny beräkningsmall med vindlastberäkning för väggar och olika taktyper enligt Eurokod.I dagsläget använder företaget en beräkningsmall som är baserad på gamla normer enligt BKR. Dessa normer kan dock inte användas längre enligt nya bestämmelser inom branschen. Enligt de nya bestämmelserna bör dessa vindlastberäkningar genomföras med hänsyn till Eurokod i framtiden.För att kunna beräkna vindlasten enligt Eurokod och effektivisera beräkningsgången har man utvecklat en beräkningsmall baserad på Eurokod. Alla nödvändiga parameterar enligt standarder har använts i beräkningsmallen och användaren tillåts genomföra en snabb och enkel inmatning av projektmått för att på ett automatiserat sätt genomföra belastningsanalysen.
Optimering baserad på vinds tillgångar
yield optimization, wind energy, sustainability, maintenance..
Beslutsfattande och uppmärksamhet : Heuristikers påverkan på kognitiva resurser inom konsumentpsykologi
Every day we make numerous decisions. Some are better than others. Intuitive decisions usually results in less good decisions when we do not reason about our choices. Research has been interested about the process that is behind how we make good decisions. Decisions we face every day, such as when we shop, determined using various mental shortcuts that we use unconsciously.
INOMHUSMILJÖ I SMÅHUSMED FTX-VENTILATION : EN LITTERATURSTUDIE MED ENKÄTUNDERSÖKNINGAR OCHMÄTNINGAR
This master thesis was initiated with the aim to answer at what level of installed capacity of wind power in the northern parts of Sweden it would be beneficial to improve the transmission capacity from the northern Sweden. During the process of this work the aim has changed to try and create a model that can be used to analyze how well the hydro power installed in the northern Sweden can even out the quick changes in wind power production.To create a good model of all hydro power in northern Sweden is a very large job, unfortunately too large for a master thesis. This report therefore ends with an extensive analysis of the simplifications that have been made and their effects as well as a list of the future work that has to be done.The model that has been created have shown to be effective and produce good results. The conclusions that can be made is that the northern Swedish hydro power have very good possibilities to balance the wind power production. Only a few cases where water have been spilled even though there has been some free capacity has been discovered.
Utveckling av golvlucka för hoppgropssystem i kommunal idrottshall
In this thesis a concept for floor hatches for foam pits has been developed. Since there is an existing solution that is powered by hydraulics and is expensive, the goal was to develop a cheaper solution, as simple as possible.A number of different concepts were developed and evaluated. A concept with five sections that are pulled to the side and stacked on each other was chosen as it was thought to have the lowest risk of crush injuries and to be easiest to manage and control. In the opening behind the foam mattress a lifting table is placed to regulate the height of the stacked sections.To be allowed to be installed in the floor of sports halls the sections must be dimensioned according to the construction standards for these types of buildings. Different dimensions of beams in steel and wood materials were evaluated and of those, who lived up to the requirements of the standard, a concept was chosen.
Utveckling och tillämpning av modeller förkvantifiering av de ekonomiska konsekvensernaav ökad förbrukningsflexibilitet inom eldistribution
One step towards a more sustainable energy system is to create a more flexible electrical grid, where increased demand response among electricity consumers can play an important role. A distribution grid owner can encourage their customers to use electricity more evenly distributed during the day by introducing different types of grid fees such as time-differentiated power tariffs. In this master thesis, the theoretical economic impact of a flattened load profile for a distribution grid owner is investigated. Different factors that impact the distribution grid owner?s economy are identified and two are chosen to be quantified; losses in the grid and the fee to the feeding grid.