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10844 Uppsatser om Electric power system - Sida 5 av 723

Utvärdering av ett Bränslecellsdrivet Flygplan.

 With the increases in fuel costs due to the depletion of the world oil reserves and the increase of greenhouse gasses as a consequence to using oil as a fuel many companies are looking to new and innovative ways to power their aircraft. One of these new ways to power an aircraft is using fuel cells powered using hydrogen and oxygen, thus producing nothing but water vapour and small amounts of nitrogen dioxide as well as trace amounts of other emissions. Both Boeing (1) and Politecnico di Torino (2) have shown that it is possible to build an all-electric aircraft powered by fuel cells. Both flights used small, two-seater aircraft and a constant between them was the loss of the co-pilot seat due to weight and lack of space. As this paper will deal with a commercial aircraft a primary concern is the cargo and passenger capacity and whatever impact switching propulsion system has on these.

Modeller för studier av ursprungsmärkt el

The EU has decided that it should be possible for consumers to get information about the origin of the electricity they buy. Therefore, there is a need to examine different systems for electricity disclosure. In this thesis two ways of disclosure have been studied:? Certificate system. A certificate system involves two parallel markets, one for trading electrical energy and one for trading certificates of origin.? Separated Markets.

NATO:s luftkrig i Kosovo utifrån Wardens teorier

John A. Warden III is one the most mentioned air power theoretic of his time.He has written a number of theories concerning air power and the best way to use this to win wars.The author of this paper gives a short resume of what he consider are the central thoughts in John Warden´s theories. These thoughts result in four factors; Enemy as a system, centre of gravity, parallel attack/concentration and finally air superiority. These factors are then being used to inves-tigate if NATO used Wardens theories during the Kosovo war in 1999.The reason for the author to choose the Kosovo war specifically is due to the fact that NATO during the war only used air power as an instrument to get Serbia´s president Milosevic to the negotiation table but also the fact that this would turn out to be quite a challenge for NATO.The conclusion is that out of the four factors only one is traceable throughout the entire operation, and that is air superiority. Regarding the other three factors they can only be found in parts of the operation..

Termisk hantering av litium-jon- batterier i elektriska drivsystem

The automotive market is currently undergoing a historical change where stricter emission legislations and ever increasing fuel costs have intensified the search for effective alternatives to the conventional internal combustion engine, which has resulted in a substantial trend towards electrification of powertrains. Storage of electrical energy is the fundamental component in this technology where the lithium-ion batteries are currently considered as the most appropriate solution. Lithium-ion batteries, however, as other types of batteries, can only be used efficiently and durably within a specific temperature range.This Master thesis has been carried out in collaboration with Electroengine in Sweden AB, situated in Uppsala, which has an ongoing project regarding development of a modular battery system for electric powertrains. The project is at a stage where an initial prototype has been developed which provides the foundation for this thesis. The study has addressed the battery system performance from a thermal perspective, in order to validate the ability of the system to create a thermally serviceable environment for the lithium-ion battery cells.

PPP - Ethernet gateway RS232 - RJ45 network adapter for an Echelon ?Data Concentrator?

För närvarande läses elmätare av en gång per år, detta leder till att kunders elräkning baseras på ett schablonbaserat belopp. Enligt riksdagens proposition 2002/03:85 skall dock alla elkunder, senast fr.o.m. 1 juli 2009, faktureras efter faktisk elförbrukning varje månad. Detta har lett till en stor marknad för fjärravlästa elmätare som nu är ett måste för att kunna utföra den tätare avläsning som krävs. E.ON ES Sverige AB som är beställare av detta examensarbetet har specialiserat sig på att installera, underhålla och läsa av fjärravlästa elmätare åt nätägare.

Smarta lokala energisystem, Vision-Teknik-Tillämpning

The energy sector is facing an impending paradigm shift. Today?s technology enables the end-user to generate their own energy locally at home. Furthermore, recently developed storage technologies make it possible to balance energy demand with stored energy and integrate district heating with the local power grid. This means that in the future heat and electric power will interact and energy flows is converted over energy boundaries.

Småskalig elproduktion i Arvika

Arvika Fjärrvärme AB, a district heating company from Arvika, today cover 74 % of their total energy production with biofuel wich runs a 16 MW bioler giving process water at saturated liquid state.In recent years Vaporel AB has introduced a new tecnique that gives an external generation of steam after boilers. The concept is built on an adiabatic pressure drop of the saturated liquid in a so called Flashbox which makes a small part of the liquid to evaporate. The generated steam is lead into a turbine where electricity is in a conventional manner.The purpose with this rapport was to do a basic study for the specific system at Arvika where it?s possible to see the potential production of electricity that follows an installation of a flasbox.The final goal was to introduce an economic analysis of a flashox installation at given conditions.To reach our goals we have created a model in Excel where we used the given conditions at Arvika Fjärrvärme to do our calculations. The model has been tested at three different states, of process water returning to potboiler, to be able to decide the optimal operation for the system at present.The studies have resulted in a pressure of the processwater at 14,5 bar (at) and a pressuredrop to 9,5 bar (at) in the flashbox.

Elkraftsystem för fälttest av Polygeneration system EXC

I ett modernt samhälle är elektricitet en nyckelkomponent för industrins, individens och samhällets utveckling. Naturkatastrofområden där elektriciteten slagits ut står inför stora prövningar för att kunna få samhällsviktiga funktioner att fungera igen. Med hjälp av den mobila miljövänlig energienhet Emergency Energy Module (EEM) kan elbehovet lindras.Detta examensarbetes mål var att ta fram en elsystemsbeskrivning för den kommande Export container (EXC), samt ta fram ett korrekt elschema för den befintliga EEM.Elsystemsbeskrivningen måste ta hänsyn till EXC:s kravspecifikation samt innehålla Bills of Material (BoM) och elschema. Problematiken ligger bl.a. i att få flera olika energikällor (sol, vind och biomassa förgasare) att fungera tillsammans i ett elsystem där likspänning, växelspänning, trefas och enfas blandas.

Analys av skillnader mellan internationell och svensk rapportering av inträffade händelser på kärnkraftverk

Report of diploma work conducted at the Swedish Radiation Safety Authority (SSM) as part of the bachelors program in Nuclear Engineering at Uppsala University.All nuclear power plants in Sweden are obliged to report any deficiency in their barriers or the defense in depth in obedience to SSM?s regulations concerning safety in nuclear facilities. In addition, there is an international system for reporting such events. The purpose of this thesis is to study the Swedish report system and to analyze the differences between Swedish and international event reporting.In the Swedish system, SSM?s regulations are effectuated by means of event reports classified as category 1-3, designed individually at each Swedish facility.

Ny stamstation i Yttermalung för anslutning av vindkraft : Nätstudie av olika utföranden i normal- och reservdrift

Since 2004, wind power has had the largest installation of new capacity compared to other energy sources in Sweden. Accommodating new wind power may require strengthening or rebuilding of the existing grid in areas where the grid is already loaded to maximum capacity. This master thesis examine the possibility of a new 400/130 kV substation in Yttermalung, Sweden, with a connection to the two neighboring regional grids in Dalarna and Värmland owned by Fortum. This substation would provide a new connection point to the Swedish transmission system as well as an interconnection of the two, currently separated, regional grids. Different expansion scenarios where a substation with and without series compensation or a phase shifting transformer (PST) to control active power flow were studied.

RCC-Jordfelsskydd, mätmodul för övertonsanalys

The majority of all power cuts that affects individuals and communities are caused by earth faults on the power transmission lines at 10kV and 20kV level [1]. If these power cuts could be eliminated, less disturbances and interrupts would lead to large amounts of money savings.Swedish Neutral has developed such a protection system. When an earth fault occurs power is injected into the neutral point of the transformer. The RCC (Residual Current Compensation) protection calculates a compensation current exactly 180 degrees out of phase to the fault current. Doing this, the voltage at the fault location becomes very close to zero, without affecting the power transmission.The protection system can only compensate automatically for the fundamental frequency (50Hz), and manually for the 3rd, 5th, 7th and 9th harmonics.

Energieffektivitet i datahallar

The number of data centers and their capacity is increasing throughout the world. Theenergy used in these data centers and the emissions from the use are increasing at thesame rate. The total use of energy will double from 2008 to 2011 based on the trends indata centers use. Research in this area says that the emissions from data centers willhave surpassed the level of airline traffic in 2020. The index used today to compare howefficient a data center is, called PUE, is lacking some information.

Bikeshare - Elcykel : Framtagning av dockningsstation till cykeldelningssystem

The project was carried out together with OC Off Course who manufactureand distribute mainly electric bikes.In today?s society, alternative sources of transportation becomes more andmore present and several bicycle sharing programs arises in major citiesacross the world every year.Something that doesn?t exist too much as of yet is bike sharing programsthat uses electric bikes. An electric bike is a convenient way oftransportation as well as a good way of avoiding traffic. With an electricbike you avoid having to sweat when biking over hills or when you need totravel over longer distances.The goal of this project is to develop a bike sharing station according tothe functions need to be met.This thesis Is based on Fredy Olsson´s methods principkonstruktion aswell as a couple of concept generating methods from Kenneth Österlin.From this, a number of sketches were made that later was evaluated inseveral steps in conjunction to a set of specifications. A 3D model of theselected concept was later made in CatiaV5 for a complete product..

Magnetfält alstrade kring nätstationer i samband med lokaldistribution av elkraft : Magnetic fields generated by electrical substations during distribution of electric power

Abstract: This report covers primarily the work of documenting electromagnetic fields generated by one of the later parts in the electrical power distribution chain: The electrical substation, wherein 10 kV is transformed to 400 V for use by private consumers. Thus it is one of the most widespread and frequently occurring parts in the Swedish power grid and of particular interest, as electrical substations are found everywhere in populated areas, often in close vicinity to people and animals.The report deals with a number of formulated questions and/or hypothesis? stated at the onset of the work undertaken, theory that is relevant for the topics the report covers, the details of the field work undertaken and the following analysis of the readings, which in term provide answers for the questions stated in the beginning. It also covers what is the currently known short term and long term risks associated with electromagnetic fields in the power frequent spectrum and of varying intensity in the vicinity of humans.The analysis also provides recommendations and identifies several points to carefully consider when planning for new installations or replacements of some parts of existing installations.For enhanced reading comprehension there is, aside from sections with pictures and attached explanatory texts and templates, several graphs, one-line diagram and maps of the power grid among the appendixes to the rapport..

Gotlands solelpotential

The aim of this thesis is to investigate the electric solar potential on the Swedish island Gotland. The Gotlandic habitations have been divided into four house categories. For each category energy demand, roof area, geographic orientation androof tilt have been decided. Solar radiation data have been collected from the Swedish solar radiation model STRÅNG (STRÅNG, 2012).The buildings characteristics and the solar radiation have been used as input values in common solar formulas, the solar potential for each building category have been summed up to a total electric solar potential for the region.The electric solar potential on Gotland was calculated to 242 GWh/year with solar data from 2010. Gotlands largest city, Visby, is marked as cultural heritage by UNESCO (UNESCO, 2012).

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