Målet med detta examensarbete, utfört på uppdrag av Vectura Consulting AB, har varit att undersöka möjligheten att ansluta en vindkraftpark till järnvägens kontaktledningsnät. Möjligheten att koppla om vindkraftparken till järnvägens hjälpkraftnät, som bland annat förser växelvärmare och signalsystem med effekt, har också undersökts. Eftersom kontaktledningsnätet och hjälpkraftnätet arbetar med olika frekvenser och spänningar, 16? Hz och 15 kV respektive 50 Hz och 22 kV, måste därför en komplett krets för frekvensomvandling, spänningsomvandling och omkoppling tas fram. Projektet har begränsats till en del av Botniabanan, sträckan Örnsköldsvik-Nordmaling.I denna rapport har trafikfrekvensen på den valda sträckan på Botniabanan undersökts för att bestämma en genererad effekt till inkopplingspunkten, samt för att undersöka när det kan vara lämpligt att koppla om till hjälpkraftnätet.

Ett digitalt vågfilter av Richardstyp har implementerats i en FPGA på ett utvecklingskort. Sampel kan skickas till filtret och mottas från filtret via serieporten på en dator. Metoden som användes är att en modell av filtret konstruerades i Simulink. Filtret har modifierats med avseende på skalning, brus och stabilitet. VHDL-koden till filtret genererades i Simulink genom att bygga modellen av Xilinx Blockset.

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..

Modern technology and fast development of heat pumps, the hunt for savings in energy consumption and the strive for environmentally friendly energy sources, convenience, and financial profit, have made heat pumps a reasonable alternative for the heating of houses.When the heat pump starts it will consume a considerable amount of current, which may result in a short-lived voltage-drop if the power grid is weak compared to the start-up current.The company Fortum Distribution which owns and administrates electrical network is interested in an investigation that deals with heat pumps affect on the quality of electricity.The purpose of this investigation is to study fast electrical fluctuations (flicker) as a result of start-up currents for single as well as multiple heat pumps on the same electrical station and from this evaluate whether there will be any problems installing heat pumps..

The Division of Language and Communication at Chalmers uses a web-based language tool, named EngOnline, to teach English grammar. The language tool suffers from some shortcomings. These include stability problems and an outdated interface but, above all, there is no documentation. Because of the lack of documentation and EngOnline?s need of maintenance, the Division of Language and Communication has decided to replace the language tool with a new and well documented one.The new language tool was developed using an agile work process; detailed documentation was replaced with more efficient communication.

This essay deals with development in Latin America. We have picked out some factors that the theories in development theory emphasize on. The first section of the study consists of a statistical analysis, were the main purposes are to study the relationship between the independent variables and the dependent and to choose which two countries we should focus on in the next section. The countries we decided to study were Costa Rica and Nicaragua, because these countries have shown very different levels of development. From this study we have concluded that political stability, economical investements and human investments are the most important factors when creating development..

The aim of this study is to look how the Social Service has handled custody issues. The study has a legal and social aspect with a purpose to investigate how the law affects the social administration as well as the family. During a period of one year a quantitative and qualitative study was performed within the social administration in a nearby community. The study focus is partly on the relationship between the law, family and society. The main questions have been: Which one of the parents, mother or father, did in fact get the custody and why? How has the children?s point of view been reported in the inquiry? A child needs a well organized everyday life in a preferably conflict free environment.

This paper describes a method for wireless energy transfer via near-field electromagnetic inductionthat is inexpensive, simple and can be applied to almost any type of system, regardless of size andenergy demands.The method uses a primary unit consisting of an oscillator, amplifier and inductive coil thattransfers energy to a secondary unit consisting of a coil, rectifier and voltage regulator. Two typesof oscillators and several amplifier designs were realized and evaluated together with a multitudeof flat coils of both monofilar and bifilar type.The results show that it is important to use an oscillator whose frequency is dependent on theinductance of the connected transmission coil, such as the Colpitts oscillator. This is preferable toan oscillator with a preset frequency, such as a Schmitt-trigger oscillator..

The purpose of this study has been to look how pedagogic process interacts in horse riding lessons. In order to research this problem I have used an ethnographic approach and during a week I observed ten riding lessons in two separate Riding house in the south of Sweden. In my theoretical frame I have used Michel Foucault ?Discipline and punish? as a toll to make clear how dominance and submission is present and active in the horse riding education. The conclusion shows how dominant power rules by its presence and creates submission, stability and feeling of security. The discipline is used to create a feeling that will bring the riders to new experience and develop their talent.

The purpose of this project was to further develop and complete a quadcopter that had been built in an earlier course at KTH, so that it could be used for demonstration and education at the school. The quadcopter was at the beginning of the project completed when it came to hardware, and there was some software functionality implemented but no system for automatic stabilization. The main goal of the project was to implement such a system, and to combine it with the previous functionality to make the quadcopter operable and able to fly. To create a functioning and stable ground multiple basic software features has been implemented, and on top of that additional software to improve the safety, stability and functionality. The most important part is the control system that is responsible for converting sensor and control signals to suitable motor values.

The structure of the thesis is based on opportunities to attract businesses to the region, the need of establishments in the region and benchmarking with establishment strategies of other cluster initiatives. The identified opportunities are the local business relationship with ABB, the prerequisites of life quality in the region and the availability of financial support. Further on has a number of opportunities to be developed been identified; diversification of the existing businesses, an expansion of the cooperation with universities and to simplify the contact with local authorities. Challenges that HVV is facing is: creating a more dynamic labor market, secure long-term labor supply, spread the image of the brand HVV and finally putting HVVs geographic scope. Two of the identified needs of establishments are strategically important: to establish a third-party logistician and commercializing systems for distributed generation and energy storage.

ABB Surge Arrestors in Ludvika have for a long time had a problem to keep the moisture at a steady state in the production of their ZnO-powder, that is used to produce varistors.Some black-box models of the spray drying process have been designed and evaluated to find a solution for the problem. After evaluating the collected data it has been found that variations in the supply voltage causes control difficulties for the operator. A cascade control system was designed, consisting of three PI control loops designed with lambda tuning. The disturbance in the supply voltagewas used as a feed forward in the control system.At the end of the project the control system was installed, and tests were made to verify the functionality of the regulator. It was shown that most of the variations in the moisture of the powder could be eliminated using small resources, through purchase of a process controller and four power meters.

Nation building is vital in post-war states to bring the people that have been at war together. To restore peace in a state, many different actors need to work together to bring stability, safety, and advancement to a new nation. There are several methods of nation building, and this thesis evolves around three of them. This is a qualitative study where three theories on nation building are used to analyze the development of nation building, and the obstacles Bosnia and Herzegovina still has to reach a national identity. Several studies are used in this thesis to show how the development has evolved in Bosnia and Herzegovina.

This thesis studies the negative impact that control signal saturation may have on a controlled system. Different methods that are used to compensate for this problem are also studied and evaluated. Both sensitivity to disturbances and the effect the method has on the systems'ability to follow a reference signal will be examined. Stability will be discussed, but no conclusions whether the systems are stabilized or not can be drawn. Control signal saturation will lead to a slower behavior in general.

Marknaden för industriella distributörer har upplevt stora förändringar under de senaste decennierna. Trots att industribolag nu har större möjligheter att sälja direkt via internet har distributörerna generellt sett stärkt sin position av flera anledningar. Forskningen har emellertid förespråkat att det är starka samarbeten som skapar värde i distributionskanalen. I huvudsak har detta påvisats med kvantitativa studier och forskare har därför efterfrågat kvalitativa ansatser.Delvis med målet att fylla detta forskningsgap utfördes en fallstudie om ABB Low Voltage Products distributörsförsäljning av produktkategori Pilot Devices, som bland annat innefattar tryckknappar. Pilot Devices valdes eftersom de är typiska distributörsprodukter i flera avseenden.