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2724 Uppsatser om Electrical power - Sida 3 av 182
Pengar, press & partiledare : En studie om porträtteringen av makt i svenska tidsskrifter
We have studied how power is portrayed in Swedish journals by analyzing eight portraits of Swedish persons with economic or political power. We have studied how they and their power are described by the journalist in text and picture. We wanted to see which picture the journalist shows of people with power, what properties they are given by the journalist and how this picture is shown by the texts and the pictures. We have also looked if there are any differences between people with political power and people with economic power. We have under our studies noticed that the persons with power are described as very successful and special and this picture are shown in a very clear and unproblematic way..
Undersökande journalistik : En analys av Uppdrag gransknings dokumentär om IKEA
This essay is about power in the classroom. It is about the power dimension of the student-teacher relationships that arise in that space. The overall aim has been to investigate which categories are fruitful in a power analysis of these relationships. My aim has therefore been to develop power categories and to use them to identify and to categorise cases of power interaction that take place between those particular actors in that particular setting.In order to gather material for my study I have both read literature that approaches the study of the student-teacher relationships from a power perspective and done a series of observations in a high school.My theoretical frame comprises a concept of power and a series of power categories. These categories include strength, authority, inducement, coercion, violence, resistance as well as to possess power, to have power, to exert power, the scope of power and the base of power.
Torkning av flis med restvärme : Metoder för att sänka återledningstemperaturen
The purpose of this study has been to evaluate whether a Low temperature bio-mass dryer could be integrated with the local district heating system in Malå. The aim is to increase the thermal efficiency of the cogeneration plant in Malå, by lowering the temperature of the cooling medium. Another benefit that comes from this is improved combustion efficiency at the power plant, since drying the fuel causes an Increase of the heating value.Simulations has been made in Excel, and with use of linear regression, to find out if it is profitable. Data for this purpose has been supplied by the power company Skellefteåkraft and furthermore SMHI.The result of the Calculations shows that a very efficient bio-mass dryer is needed, if yield of investments should be made possible. An Investment of 4,27 Mkr, in a dryer, could at a such criterium return 60000 kr/year, if the price of the biomass is 190kr/MWh.
Scenarioanalys över Sveriges elproduktion år 2050 : Kan Sverige försörja sig med 100 % förnybar
The aim of this report was to investigate if Sweden can have 100 % renewable electricity production in the year 2050. The conclusion is that it is possible but under certain conditions. For instance wave power must be in commercial use. When wind power and solar power represent a large percentage of the electric production there will be a lack of electric power during the winter but during the summer there will be a surplus of electric power. Both the surplus and the lack of electric power need to be taken into account.
Risk- och sårbarhetsanalyser för smarta elnät
The electrical grid needs to be changed in the future in order to manage more distributed and renewable generation and also to make it possible for electricity consumers to be more active and aware of their electricity consumption. This future grid is usually referred to as a smart grid. With the transition to a smart grid, new challenges occur. One method to determine those challenges is to perform risk and vulnerability analyses. InStockholm, the new urban district Stockholm Royal Seaport is built.
Test och verifiering av en ny inkapslingsmetod för SiC BJT och MOSFET
The use of silicon carbide (SiC) as a base material in power electronics has manyadvantages, including high breakdown voltage and excellent temperature endurance.However, the packaging of such electronics presents major challenges and there is aneed for packaging that can operate in higher temperature. The purpose of this thesishas been to develop a test method and verify the functionality of SiC powertransistors prototypes with a new packaging technique developed by Swerea IVF AB.It includes setting up an electrical test-bed for power and high temperature cyclingand analysis of the results. Even though test confirmed functionality after thepackaging process, (at room temperature) the performance seemed to have been reduced. This could be a result of the measurement setup and the packaging process.In higher temperature the transistors failed to operate longer than a couple ofminutes which showed the weaknesses in the design and the challenges with this typeof packaging..
Innovativt Drivpaket för Rullstol
This is a thesis for a Bachelor Degree Project, performed in the subject MechanicalEngineering. The students Roger Malmberg and Simon Hagberg have carried out adesign project on behalf of the recently established company J&D Assisting systems,located in Halmstad.The project consisted in developing J&D's first prototype of a power assisting solutionfor wheelchairs. A power assisted wheelchair combines human power, which is deliveredby the arms through the pushrims, with electrical motors, which are powered by a battery.The power assisted wheelchair is aimed at customers, who have used a regularwheelchair for a long time, but who have become weaker or just need additional powerwhen driving uphill. This kind of wheelchair will provide additional power for users,which will spare their wrists, elbow and shoulders. The product is torque sensor free andinstead it relies on the velocity.
Infärgning och samarbete på El-programmet : staining and cooperation in the Electrical program
This work is about collaboration and staining in the upper secondary school Electrical program. How should the coloring go to in order to increase students' motivation and thus facilitate students' learning is the main subject with the work. The study has shown that there is a functional co-operation today, and that students believe that if the cooperation would increase. It would also in-crease their motivation to improve..
Konceptstudie av kombinerad nödgenerator-trädgårdsredskap : Concept Study of a Combined Emergency Generator-Garden tool
The present study concerns a concept development of a product idea that Bengt Magnuson, associate professor, had when a heavy storm caused a widespread power failure of long duration. With a basic power-producing unit one should be able to get through a power loss. The product could also be useful for other tasks if different modules are connected, e g grass mower or snow-blower.According to the product idea the basic unit will be able to produce electric power enough for a fridge, freezer, TV, and a few electric lamps. Normally the basic unit can be used e g as a mower, when such a module is attached. An increased number of tasks would make the contraption useful and tempting for those who do not own an Electrical power set in reserve.
Säkerhetsanalys av brandbekämpning i kritiska utrymmen på Forsmark 1
In order to maintain a high safety level at a nuclear power plant it is important not only to measure the reliability of the components and systems of the plant, but also to investigate how the plant responds to human actions. One of the most hazardous situations in managing a power plant is fire occurring in critical areas. This study concerns the prospect of the local fire brigade to suppress a fire that has started in one of the most critical rooms for maintaining high reactor safety. The model created gives an indication on the possibilities of succeeding in suppressing a fire. In order to get a more reliable fire fighting the following advice are given:- Let the fire brigade go rounds in the plant together with the personnel, during which recommended fire suppressing methods are determined to avoid long preparation time in an actual situation.- Prepare rooms with two subsystems to make them partly with no voltage.- Give the fire brigade better feedback from actual events on nuclear power plants.- Education and training in suppressing fires in electrical equipment.The probabilistic safety assessment strives to be as realistic as possible.
Nätanslutning av vindkraft : vindkraftsbranschens aktörers perspektiv på nätanslutning och tariffer
Wind power is a growing energy sector in Sweden. However, it still represents only a small part of the total electricity production, about 0.7%. In order to create good conditions and to facilitate the establishment of wind power in Sweden, the government has for example, created a national centre for wind use. The objective has been to reach the governmental goal, which is an expansion of wind power by 10 TWh by year 2015 compared to the level in 2002.
The Swedish electricity market was deregulated in 1996 which refers to the introduction of a competitive market in electricity production and trade.
Hur påverkar en ökad andel solceller Umeå Energis elnät? : ? En utredning med fokus på spänningsvariationer och osymmetri inom landsbygds- och tätortsnät vid en- och trefasanslutning av solcellsanläggningar
A good power quality can be an important prerequisite to achieve a sustainable society. Scandinavia's electrical system is in many respects superior, and Sweden has a fossil free electricity generation at 97 % and a reliability of electricity distribution at 99.98 %. Meanwhile, the EU has an ambition to expand the electricity market in order to achieve a joint trading business across Europe. This cross-border market will result in a large proportion of fossil energy sources integrated into our electrical system, which also leads to an increased need for renewable electricity production in Sweden. One part of this development is to increase the share of renewable micro generation that is locally or regionally connected to the power grid.
Makt i klassrummet : En maktanalys av relationen mellan lärare och elev
This essay is about power in the classroom. It is about the power dimension of the student-teacher relationships that arise in that space. The overall aim has been to investigate which categories are fruitful in a power analysis of these relationships. My aim has therefore been to develop power categories and to use them to identify and to categorise cases of power interaction that take place between those particular actors in that particular setting.In order to gather material for my study I have both read literature that approaches the study of the student-teacher relationships from a power perspective and done a series of observations in a high school.My theoretical frame comprises a concept of power and a series of power categories. These categories include strength, authority, inducement, coercion, violence, resistance as well as to possess power, to have power, to exert power, the scope of power and the base of power.
Axle Link - en kortslutningsskyddad säker DC-överföring
Denna examensrapport redogör för hur man kan få en kortslutningsskyddadoch säker inkoppling av en DC-länk mellan två skiljda elektriska system.Rapporten bygger på hur en lastbil ska kunna få en större säkerhet för attbibehålla sina elektriska bromsar om tex ett av bromssystemen tappar sinordinarie matning.Lastbilens bromssystem består idag av två skiljda elektriska system med ett 24volts strömförsörjande batteri vardera. Det ingår två stycken elektriskabromsar i varje system. Om det tex blir fel på en av bromsarna och dennapåverkar ett av systemen vill man kunna koppla bort denna enskilda bromsmed sitt system. Man vill även kunna försörja den fungerande bromsen somsitter i samma system via en så kallad Axle Link. Denna strömmatningslänksitter mellan två hjulpar på samma axel.I denna studie undersöktes möjligheten att realisera en kortslutningsskyddadoch säker DC-överföring via en Axle Link, i första hand med diskretakomponenter.
Hur håller jag i 30 år? Vad krävs av mig som lärare?
AbstractThe future of ethanol is depending on good solutions for the production. ENA energy power plant produces Electrical power and district heating by heating biofuel. By building an integrated bioenergy plant surplus steam could be used to produce ethanol as fuel to vehicle.This would mean that ethanol is produced renewable energy and the energy for the process derives from the surplus of power. ENA energy, MDH (the University of Mälardalen) and the energy authority has initiated a research project were different bioenergy combinations integrate with existing power plant. As a part of the project which size an integrated factory should be to gain the best efficiency for the plant was investigated. Consideration will be taken to the cost of the production in order to be competitive to the price of imported ethanol. Etanolens framtid vilar på bra lösningar för framställning. I ENA energi kraftverk i Enköping produceras el och fjärrvärme genom eldning av biobränsle. Genom att bygga ett integrerat bioenergikraftverk där skulle man kunna använda överskottsånga till att framställa etanol som fordonsbränsle.