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.

This master thesis has been performed at Vattenfall Power Consultant in Gothenburg and Trollhättan for Vattenfall Vattenkraft. In this report vacuum circuit breaker in small-scale hydropower stations with the rated power 4 MVA and below has been studied. Models of the stations are modeled and analyzed in PSCAD/EMTDC to study the high voltage transients that are created after current chopping with vacuum circuit breaker. Vacuum circuit breaker may chop the current before it reaches zero value, which means that high voltage transients can be created. The equipment of the stations can be destroyed by high voltage transients.The purpose of this thesis is to examine the use of vacuum circuit breaker in small-scale hydropower stations and the risk for high voltage transients from current chopping.According to the results there is a risk of high voltage transients after current chopping with small synchronous generators in stations with the operating voltages 0.4 kV and 3.6 kV.

The aim of this study is to increase understanding about addiction recovery. More specifically, we want to know what people who have had problems with alcohol and/or other drugs perceive as helpful and important for their recovery process and how we can understand this process.The study was conducted by means of qualitative semi-structured interviews with four people who have had alcohol and/or other drug problems. The analysis is based on a transtheoretical model of change from addictive behaviours, coping, interactionist theories and also a recovery perspective, inspired by research on recovery from mental illness . Main findings are that recovery from addiction can be understood as an individual process that takes place in a social context and can follow expected phases, although there are large individual differences in the process. Through the recovery process it has been of importance to the participants in the study to redefine themselves and their problems, get support from others, find ways to cope with their problems, get involved in meaningful activities and to expand their social roles.

The aim and goal of this work has been to design and implement a voltage reference network for a 12-bit PSAADC, Parallell Successive Analog to Digital Converter. A chip containing the design has been sent away for fabrication. Because of the long processing time, no measurement data are presented. The main specifications for the voltage reference generator is to generate stable reference voltages with low noise and a good PSRR. Efforts has also been made to minimize the power consumption..

Microproduction, also called distributed generation, is something that has become more and more popular in the electric grid. Microproduction can however lead to unacceptable performance if several units are installed in the same low voltage network. It is therefore good to know a limit where the performance of the low voltage network becomes unacceptable based on given parameters. This limit is usually called hosting capacity.In this report the hosting capacity with respect to voltage and current have been studied in three low voltage networks which are located in Falu Elnäts concession area. This has been done by simulations in a GIS-program where critical times of the grid have been simulated.

Minimizing power consumption is a critical part of many embedded design projects. Thechallenge is to limit the power consumption of the system and at the same time providesatisfactory service to the user. With regards to microprocessors, the main way of limiting powerconsumption during program execution is to adjust the frequency and the voltage at which theprocessor operates.To enable the implementation of real-time scheduling with support for dynamic voltage andfrequency scaling, an exhaustive study of the Freescale i.MX31 embedded microprocessor isperformed. Specifically, the power consumption relationship to all relevant frequency andvoltage settings is investigated. In addition, to enable frequency and voltage scaling in a real-timeenvironment, a complete timing analysis of proposed voltage and frequency scaling methods isperformed and their suitability for use in real-time systems is evaluated.To integrate voltage and frequency scaling capability into OSE RTOS, a software module hasbeen developed for this operating system.

In this thesis a rural network in Norrbotten, Sweden, has been to designed and planned with the purpose of improving distribution reliability by exchanging existing overhead lines with underground cables. General network design considerations are discussed as well as the ones for the specific low voltage grid. During the design phase the maximum power of domestic consumers has been estimated using Velander?s method. Currents, voltage drop and impedance of the network have been calculated and fuse operation and selectivity has been considered.

Uppsatsen skrevs i samband med Konsumentverket och undersöker hurKarlstadsbuss använder sig av service recovery i sitt dagliga arbete.Service recovery innebär att så fort en kund upplevt något negativt i samband med ett företagsmöte så ska denne få återkoppling i form av en ursäkt, pengar tillbaka eller någon annan typ av förmån. Lyckas företaget ge kunden detta så fort som möjligt så förhindrar det att kunden får en negativ bild av företaget som den sprider vidare till personer i sin omgivning.För att få djupare kunskap i ämnet har tidigare teorier om klagomålshantering, service recovery och hur företag kan motivera sina anställda till att vara mer serviceinriktade studerats.Syftet med den här uppsatsen är att studera hur service recovery används i ett kollektivtrafikföretag och hur det tillämpas i hela organisationen.Först studerades teorier inom ämnet och sedan gjordes en empirisk undersökning, uppsatsen är med andra ord uppbyggd enligt den deduktiva strategin..

ABSTRACTBackground: After general anesthesia the cognitive ability is temporarily impaired. Cognitive recovery is necessary for the patient to be able to assimilate the information that she / he gets postoperatively. It also increases the patient safety. There are few methods to estimate and assess the patient's cognitive recovery before and after anesthesia. The purpose of this study is to test the usefulness of the instrument PQRS and to assess the patients cognitive recovery after anesthesia.

AbstractThe purpose was to investigate whether a recovery perspective, viewed from a psychosocial approach is applied in municipal / private and county related care and rehabilitation. A recovery perspective means that the attending staff ensures that the clients are viewed as holistic individuals, where all aspects of life are considered to ensure adequate care and rehabilitation. A questionnaire was answered by staff in psychiatry, social psychiatry and addiction treatment from different areas of the municipal / private and county related sector.The results show no difference in application of a recovery perspective between these two types of organizations. However, there is a slight tendency (non-significant) to lower-rated general individual competencies for municipal / private. There is also a strong tendency (non-significant) to a general difference between the aspects of the implemented recovery perspective, where the tendency is that the respondents as a whole estimate that the organization to a greater degree creates good conditions for a recovery perspective compared to the degree they are actually working on that basis.

Denna uppsats kretsar kring två företags återhämtningsarbete vid uppkomsten av respektive skandal. Vidare skapas en djupare förståelse för teorin Service Recovery's betydelse och användning i praktiken. De två fallen där skandaler inträffat är grundade dels i ICA:s köttfärsskandal och dels i IKEA:s fjäderplockningsskandal. Uppsatsen har en deduktiv ansats vilket innebär att uppsatsen utgår från befintliga teorier som sedan testas med det insamlade empiriska materialet. Den teoretiska referensramen innefattar främst Grönroos teorier kring Service Recovery och kompletteras med teorier så som Service Recovery Paradox, kundförväntningar, sociala medier och immateriell påverkan.Uppsatsens forskningsfrågor besvaras främst med hjälp av en fallstudie med två företagsanalyser samt med en enkätundersökning. Studien är av både kvalitativ och kvantitativ karaktär där kvalitativ data samlats in via en e-mail intervju med Ylva Magnusson vid IKEA, och kvantitativt via en enkätundersökning.Uppsatsen har resulterat i kännedom om hur de två företagen arbetat med att återfå kundförtroende.

The dissertation deals with an account of actual problem, which can arise within EMC and power quality. The cause of power interruption and what can be done to minimise the power interruption is discussed. It also includes a definition of planning levels and which factors one needs to have control over to carry out a possible planning strategy and how the local distributions net could be more secure. The electrical net could be secure but no system can be free from interruption.The dissertation examines two distribution transformers: GLA40T1 (Glansås) and T399 in Tranås Energy which don?t have regulators.

Syftet med studien är att undersöka, beskriva och problematisera Reading Recovery samt att ta reda på varför två nyzeeländska skolor har valt att behålla respektive sluta med programmet. Undersökningen baseras på fyra kvalitativa intervjuer samt en kvalitativ observation, vilka skedde på två skolor där den ena slutade med Reading Recovery för några år sedan och där den andra skolan fortfarande använder programmet. Undersökningen syftar inte till att jämföra de båda skolornas språkundervisning, utan till att ge en bild av hur det kan fungera på en nyzeeländsk skola. Intervjuerna ägde rum på Nya Zeeland och de intervjuade hade olika anknytning till Reading Recovery. I uppsatsens bakgrundsdel beskrivs den tidigare forskningen om uppsatsens tre grundteman, det nyzeeländska skolsystemet, språkpedagogik samt stödundervisning.

Syftet med min praktikresa till en skola på Nya Zeeland var att observera deras undervisningssystem för läs- och skrivinlärning och då framför allt specialmodellen Reading Recovery. Utifrån delar av deras metod skulle jag utforma ett förslag på arbetsmodell, som kunde användas i den svenska skolan för att hjälpa lässvaga elever. Praktiktiden delades mellan klasserna 1-3 bestående av elever mellan 5 och 7 år samt med dagliga lektioner i Reading Recovery. Jag gjorde intervjuer med både elever, lärare och föräldrar med erfarenhet av Reading Recovery. Under mina observationer har jag funnit att den nya zeeländska skolan har en väl utvecklad och fungerande metod för läs och skrivinlärning och utifrån detta har jag utarbetat ett förslag på metoder som jag funnit användbara.

The voltage level in the power grid varies due to variations in load and production. Normally these variations are manageable, but they may be excessively large during a disturbance. If the voltage is too high it may damage the equipment in the grid and too low voltages may cause problems like voltage instability. The magnitude of the voltage variation depends on the short circuit power capacity of the point of interest.This problem may become lore prominent due to automatic voltage regulation that acts on shunt reactors and shunt capacitors. When the shunt reactor is connected or disconnected to the grid it may cause such large changes in the voltage that the shunt reactor starts hunting.