Voltage sag indices are a way of quantifying the performance of the power supply, as far as voltage sags are concerned. Indices can be defined for individual events, for individual sites, and for a whole system. A standard method for single-event methods is part of IEC standard 61000-4-30.This thesis emphasizes the importance of voltage sag indices and different methods for calculating three-phase voltage sag characteristics. Three-phase events measured in a medium network voltage over period of one month were analyzed, results examined and statistically evaluated. An algorithm for calculating voltage sag characteristics and indices was created in Matlab.

This thesis is the result of the investigation and solution of a mechanicalproblem regarding flywheel malfunctions. A flywheel is, in short, a devicethat relies on a rotating object?s moment of inertia to store energy overshort time spans. This project is part of the development of a fourthflywheel prototype at the division for electricity at Uppsala university,which uses magnetic levitation to keep a hollow cylinder rotating at veryhigh speeds inside a vacuum chamber. Should the magnets fail however, orsome other error occur that leads to an uncontrolled state of rotation, thecylinder needs to be stabilized mechanically by a device usually referredto as ?back-up bearing?.

Good comfort for the driver of a construction machine is crucial. Gearshift comfort is an important part of the total comfort. Volvo Construction Equipment Components has a simulation environment of the powertrain, SimPow, which is implemented in Matlab/Simulink. SimPow is mostly used for simulation of control strategies and performance. In order to be able to study gearshifting comfort, Volvo has an interest in developing new models for SimPow.

Linjäriseringar av olinjära system är mycket relevanta eftersom det finns en i förhållandevis enkel och omfattande matematisk teori kring linjära system, till skillnad från allmänna olinjära system.För vissa olinjära system är det svårt eller inte ens möjligt att genomföra en analytisk linjärisering.Orsakerna till detta kan vara hög komplexitet av systemet eller avsaknaden av ett analytiskt uttryck.Numerisk analys kan vara en lösning på detta problem.I detta examensarbete används framåtdifferens och centraldifferens för att genomföra de derivata-approximationersom behövs för att genomföra en numerisk linjärisering av ett olinjärt system.Rapporten behandlar även vad som sker då det är dålig upplösning på den indata som används när man genomför enlinjärisering, vad som händer med heltal och binära signaler om de ingår i ett system som linjäriseras ocheffekten av att ha olika samplingstider för olika delmoduler i ett system som linjäriseras.Slutligen undersöks numerisk bilinjärisering av ett system på bilinjär form och en jämförelse mellan analytisk linjärisering och bilinjärisering görs..

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.

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.

Banverket Trafik has a responsibility to make sure that the companies who traffic the Swedish railroad have the correct information about the status of the railroad. One of Banverket Trafiks information systems (Opera) presents the train?s actual position on a map and provides the user with physical information about the trains. Due to increasing demands on the information systems, Banverket Trafik needs to update the present system architecture in order to manage the increasing demands on map graphics and map functions. This paper analysis the information system Opera on the basis of theory and support of methods and discuss problems and demands for Opera.

Detta examensarbete genomfördes på ABB Power Technologies AB i Ludvika. ABB vill överbrygga gapet mellan industri och informationsteknologi för att få de båda delarna att arbeta integrerat. ABB kallar detta koncept för Industrial IT (IIT). Ett krav från koncernledningen är att alla produkter ska vara certifierade enligt nivå 0, som är det första steget i IIT: s certifieringsprocess. Målet var att utföra en kravspecifikation på ett system som ska kunna leverera certifierad produktinformation enligt IIT-standard.

Voltage sag indices are a way of quantifying the performance of the power supply, as far as voltage sags are concerned. Indices can be defined for individual events, for individual sites, and for a whole system. A standard method for single-event methods is part of IEC standard 61000-4-30.This thesis emphasizes the importance of voltage sag indices and different methods for calculating three-phase voltage sag characteristics. Three-phase events measured in a medium network voltage over period of one month were analyzed, results examined and statistically evaluated. An algorithm for calculating voltage sag characteristics and indices was created in Matlab.

Voltage sag indices are a way of quantifying the performance of the power supply, as far as voltage sags are concerned. Indices can be defined for individual events, for individual sites, and for a whole system. A standard method for single-event methods is part of IEC standard 61000-4-30.This thesis emphasizes the importance of voltage sag indices and different methods for calculating three-phase voltage sag characteristics. Three-phase events measured in a medium network voltage over period of one month were analyzed, results examined and statistically evaluated. An algorithm for calculating voltage sag characteristics and indices was created in Matlab.

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.

The goal for this master thesis project has been to investigate the power quality in adistribution grid, which has a high fraction of dispersed power production due towindmills. The study has been done on a grid in Laholm South of Halmstad, whereapproximately 45 windmills are connected to the distribution grid owned by SHKEnergi. The investigation has been focused on to two radialy fed 20 kV lines, wheretwelve windmills are connected.Voltage variations have been studied by creating a model of the grid in the simulationprogram SIMPOW. The largest deviation that has been found in any point of the gridis ±1.9 % of the nominal voltage. This deviation is a result of varying powergeneration from the windmills and the voltage regulation at the connection point ofthe line.

Abstract Title: The Social Democrats and Monarchy, a Study of three Social Democratic newspapers and their reports about Oscar II?s 25 year anniversary as king of Sweden. The Social Democrats in Sweden has almost had a power monopoly over the parliament and government during the entire 20:th century. Since the party was established in 1889 they have been against monarchy as a way of govern society. When the monarch lost political power and influence during the 20:th century, they still condemned monarchy as undemocratic. They preferred to have a republic instead, with an elected president, rather than a king or a queen.

Ever since Lipsky wrote about street-level bureaucrats in 1980 the main belief has been that certain characteristics of their jobs make it exceptionally difficult to severely reduce their discretion. However, discretion comes at a price and if public servants abuse their power the legitimacy of government is at risk and ultimately even the democracy.This thesis address this question by analysing the Swedish employment service which in the beginning of 2001 started a project called ?Af Sverige? trying to improve internal rule of law. By comparing two local and fairly equal jobcentres and how the street-level bureaucrats within use their discretion, I seek to find support for my hypotheses that organizing local jobcentres according to the principles of machine bureaucracy plays a significant part in reducing discretion.My findings show that a jobcentre characterised by strict rules, few units, good communications and a forthright manager who delegates formal power to the employees results in a stricter and more uniform application of regulations among the street-level bureaucrats. My conclusion is therefore unambiguous.

Användbarheten av IT-system förbättras ständigt och företag har fokus på att förbättra sina IT-system som företagets kunderna använder då det leder till fler och nöjdare kunder. Annorlunda ser det ut för interna IT-system, alltså datasystem som används av medarbetare och som ska förenkla arbetsuppgifter, effektivisera arbetet eller även möjliggöra att utöva arbetsuppgifter vid en arbetsmiljö på distans. Användbarheten av interna IT-system står inte lika mycket i fokus som användbarheten av kundcentrerade system och istället för att åtgärda brister i användbarheten tvingas medarbetarna att lära sig hantera IT-systemets brister.Utgångspunkten för arbetet var funderingarna över vilken betydelse användbarheten har för ett företag när det gäller interna IT-system vid en arbetsmiljö på distans. Ansatsen var att undersöka om användbarhetsproblem i praktiken leder till att användarna upplever ett IT-system som dåligt i den särskilda situationen av ett arbetsmiljö på distans. I en fallstudie utvärderades ett IT-system som används av försäkringsombud som arbetar på distans med hjälp av en enkätundersökning och användarintervjuar samt hierarkiska uppgiftsanalyser.