Detta arbete behandlar ett problem som har uppstått hos svetsföretaget ESAB AB i Laxå, då ett trådbyte ska ske av en tråd med en vikt på 100 kg i en svetsmaskin. Svetstråden sitter mellan en spole som består av en undre och övre del som skruvas fast i varandra. Spolen är därefter monterad i en arm längst bak på svetsmaskinen. Problemet med trådbytet är dels att tråden väger mycket, dels att bytet behöver genomgå flera olika steg. Först av allt lyfts den spolen med förbrukad tråd av med hjälp av en travers och läggs på marken. Sedan skruvas den övre delen av spolen av och den förbrukade svetstråden tas bort för hand. En ny trådrulle hämtas därefter med en travers och placeras sedan på den undre delen av spolen. Den övre delen av spolen hämtas efter detta, för att skruvas fast tillbaka på spolen tillsammans med trådrullen och spolens undre del. När dessa steg är genomförda lyfts spolen tillbaka på svetsmaskinens arm och skruvas fast. Svetsmaskinens arm kan bära upp till fyra spolar samtidigt. Ovanstående steg tar upp tid från arbetet som behöver genomföras och är dessutom tungt då enbart spolen väger 27 kg, utan en trådrulle monterad. Lösningen till problemet är att implementera metodiken Design For Assembly (DFA), med syftet att minimera monteringstiden och fortsätta med en produktutvecklingsprocess av spolen och svetsmaskinens arm, där spolen sitter monterad på.   Resultatet på lösningen presenteras med hjälp av ritningar i CAD, i både 3D och 2D, samt beräkningar. Anledningen till att presentationen görs med hjälp av CAD- ritningar är för att tydliggöra lösningens koncept samt för att kunna påvisa hur metodikerna har använts vid lösningen. Lösningarna har jämförts och övervägts med Pughs matris. Med de beräkningar som gjorts har även hållfastheten kunnat räknats ut för lösningen. Syftet och frågeställningen besvarades för detta arbete.  Den största skillnaden mellan detta arbetes slutgiltiga lösning och ESAB AB:s redan existerande lösning är att enbart den övre delen av spolen behöver skruvas av vid trådbyte. Detta gör att många moment kan elimineras, vilket i sin tur förkortar monteringstiden och mer tid kan ägnas åt arbete i svetsningen. / This thesis deals with a problem that has arisen at the welding company ESAB AB in Laxå, when changing 100 kg thread spools in a welding machine. The wire sits between a spool consisting of a lower and upper part that are screwed together. The spool is then mounted in an arm at the back of the welding machine.  The problem with the spool change is partly that the spool weighs a lot, and partly that the change needs to go through several different steps. First, the spool with used wire must be lifted off with a traverse and laid on the ground. Then the upper part of the spool needs to be unscrewed to remove the used wire by hand. Then is brought with a help of a traverse. The wire is then placed on the lower part of the spool. The upper part of the spool is then retrieved and gets screwed on. When these steps are completed, the spool gets lifted back onto the welding machines arm with the traverse and gets mounted on.  The welding machine's arm can have up to four spools mounted simultaneously. These steps take up time from the work that needs to be done and are also heavy. The solution to the problem is to implement the Design for Assembly (DFA) methodology, with the aim of minimizing assembly time and continuing with a product development process of the spool and the arm that the spool is on.  The results of the solution are presented with the help of drawings in both 3D and 2D CAD drawings as well as calculations. The reason why the presentation is made with the help of CAD drawings is to clarify the concept of the solution and to be able to demonstrate how the methodologies have been used in the development. The solutions have been compared and weighted with Pugh's matrix. With the calculations that have been made, it has also been possible to calculate the strength of the solution. The purpose and question were answered for this work. The biggest difference between this work's final solution and ESAB AB's already existing solution is that only the upper part of the spool needs to be unscrewed when changing wires. This means that many steps can be eliminated, which in turn shortens the assembly time and more time can be devoted to work.

The early modern age was a period of great discoveries, formulation of new ideas and new methods for scientific inquiry. It was also a time of increased travel within Europe among nobility and people of learning. In this essay a number of Swedish learned men are followed in their journeys, through their own diaries and autobiographies, to centers of learning in England, France, Italy and other countries. The essay investigates how the journeys reflect the formation of academic and scientific institutions in Europe, such as scientific societies and journals, and experimental practices. It also studies the nature of personal interactions and the mechanics of international social networks, and the role of travelers in this context. It also looks at how Sweden, as a country in the periphery of Europe, could take advantage of this kind of international travel and become part of the new developments on the continent.

The rural power grid has traditionally mostly consisted of overhead power lines. In recent years the trend has been to replace the overhead lines with cables instead. The reason is that overhead lines are relatively vulnerable, strong winds and storms can cause trees and branches to fall over the power lines and cause a phase to ground fault. This will then trip the ground fault relays and disconnect the faulty power line. A cable grid is not vulnerable in the same way, and could be considered a solution to make the power grid more reliable. A cable grid does come whit other types of problems instead. It generates about 50 times more phase to ground capacitance compared with the same length of overhead lines. When a phase to ground fault occurs the capacitance in the healthy phases will generate a current to ground and then through the fault. On average a cable grid generates about 2 A per kilometer. Large cable grids can therefore cause very large capacitive currents to flow through the fault.  To counter this, a reactor is placed between the neutral point of the transformer and ground. When a phase to ground fault occurs, the reactor will generate an inductive current which is in the opposite phase compared to the capacitive current. This current will flow through the faulty line and cancel out the capacitive current. In a perfectly tuned power grid the only component left in the fault is a smaller resistive current. Large cable grids will require a large reactor to generate the large inductive current, which might need to flow over a great distance in the grid to reach the fault location. To reduce the inductive current from the central reactor, it is possible to install smaller local reactors in the grid. These will then in the event of a phase to ground fault generate a part of the inductive current, which will reduce the currents from the central reactor. This report will look at the factors related to grounding systems and how these factors affect the ground fault currents. The purpose of the report is to give recommendations to Umeå Energi on where in their grid they should install additional local reactors and also which factors they should consider when doing future expansions and rebuilds of their power grid.

Detta examensarbete har utförts vid Saab Dynamics AB(SBD) i Karlskoga med syftet att studera gamla konstruktioner av set-back-generatorer. En set-back-generator (SBG) ska ge momentan energi vid utskjutning av en projektil genom att en magnet rör sig genom en spole. SBG har funnits länge men har bedömts ge för lite energi för att kunna driva elektronik. Men nya typer av magneter har potential att öka energiutbytet väsentligt. SBD har ett antal äldre SBG:er och arbetet har varit att utifrån dessa undersöka om det går att utvinna mer energi genom ett utbyte av magnet. Andra parametrar som är viktiga för en SBG:s funktion har också studerats och testats i olika konfigurationer i hopp om ytterligare förbättringar. Förväntade resultat har sedan analyserats och jämförts med mätresultat. Med detta som grund har rekommendationer vid en ny konstruktion av SBG levererats. / This bachelor thesis has been performed at Saab Dynamics AB (SBD) in Karlskoga, with the purpose to examine old designs of set-back-generators. A set-back-generator (SBG) shall provide instantaneous energy during firing of a projectile by a magnet moving through a coil. Previous designs of SBG:s is not providing enough energy to power electronics. New types of magnets have the potential to increase the energy yield significantly. SBD has a number of older SBG's and the work is based on these to examine the possibility to extract more energy by exchanging magnet. Other important parameters for an SBG's function has also been studied and tested in different configurations in the hope of further improvements. Expected results has then been analyzed and compared with the measurement results. On this basis suggestions and recommendations on a new SBG design has been delivered.

The development of electronic textiles has increased significantly during the last ten years. By integrating electronic components or using conductive thread you can create textiles with different technical functions. CEVT is a innovation company within the automotive industry who have gained interest in electronic textiles. The department of innovation want to explore the possibility to integrate electronic textiles into future cars. The mission they have assigned us is a sub-goal in a larger end goal in which we will investigate whether one can develope a textile that can charge a phone wirelessly. To do this, a textile transmitter coil must be produced to enable the induction charging, which is what wireless charging really means. The method that was chosen to produce the textile transmitter coil was embroidery and the conductive thread that was used was a silver plated polyamide thread (HC12) from Sheildex. The thread had a resistance of <100 Ω per meter and some difficulties arose early on, where the resistance of the embroidered coil was to high. To reduce the resistance multiple stitches were sewn together and the conductive thread was also used as a lower thread. The resistance of the final coil had an average of almost 15 Ω which was significantly higher than desired. Tests were made to measure the inductive capability of the embroidered coil. This was done by measuring the power transmission between an embroidered coil and a Samsung Galaxy s8 reciever coil. The results showed that a power transmission was enabled, which means that it works. Though the power transmission was a lot lower when compaired to a commercial transmitter coil that was tested at the same time. The project did not result in a fabric that could wirelessly charge a mobile phone. Nevertheless, the test results showed that it is possible, since a power transmission did occur between the textile coil and the coil from the Samsung. Further research and optimization of the textile coil would be required to realize the induction charging textile. Two interesting ways to go would be by using another embroidery technique called Fibre Tailored Placement (FTP) or by developing a new conductive embroidery thread, with a lower resistance. / The development of electronic textiles has increased significantly during the last ten years. By integrating electronic components or using conductive thread you can create textiles with different technical functions. CEVT is a innovation company within the automotive industry who have gained interest in electronic textiles. The department of innovation want to explore the possibility to integrate electronic textiles into future cars. The mission they have assigned us is a sub-goal in a larger end goal in which we will investigate whether one can develope a textile that can charge a phone wirelessly. To do this, a textile transmitter coil must be produced to enable the induction charging, which is what wireless charging really means.The method that was chosen to produce the textile transmitter coil was embroidery and the conductive thread that was used was a silver plated polyamide thread (HC12) from Sheildex. The thread had a resistance of <100 Ω per meter and some difficulties arose early on, where the resistance of the embroidered coil was to high. To reduce the resistance multiple stitches were sewn together and the conductive thread was also used as a lower thread. The resistance of the final coil had an average of almost 15 Ω which was significantly higher than desired.Tests were made to measure the inductive capability of the embroidered coil. This was done by measuring the power transmission between an embroidered coil and a Samsung Galaxy s8 reciever coil. The results showed that a power transmission was enabled, which means that it works. Though the power transmission was a lot lower when compaired to a commercial transmitter coil that was tested at the same time.The project did not result in a fabric that could wirelessly charge a mobile phone. Nevertheless, the test results showed that it is possible, since a power transmission did occur between the textile coil and the coil from the Samsung. Further research and optimization of the textile coil would be required to realize the induction charging textile. Two interesting ways to go would be by using another embroidery technique called Fibre Tailored Placement (FTP) or by developing a new conductive embroidery thread, with a lower resistance.

High Voltage Direct Current (HVDC) is a rapidly growing form of power transmission that offers advantages with respect to conventional AC networks. One of the key elements that will allow the generalization of the HVDC grids is the Circuit Breaker (CB), which has to interrupt high DC currents in extremely short times. The use of a Thomson coil (TC) to generate high driving forces is being considered as a suitable working principle for the mechanical actuator inside the CB. This thesis presents the design of a concept of a mechanical actuator based on the Thomson coil for SCiBreak AB, a company whose final objective is to create a complete ultra-fast circuit breaker for HVDC lines. The design phase had to face challenges with the high forces required to open a gap between electrical contacts in just a few milliseconds. A detail design for the different components of the actuator was performed and analytical and CAD models of the system were generated. This thesis also included the construction and testing of a prototype at the company’s premises. The final output was the analysis and discussion of the experimental results of the prototype, as well as suggestions for the future development of the mechanical actuator. / Högspänd likström (HVDC, från engelskans High Voltage Direct Current) är en snabbt växande form av kraftöverföring som har många fördelar jämfört med konventionella växelströmsnätverk. Ett av huvudelementen i nätet är strömbrytaren (CB, från engelskans Circuit Breaker), vilken möjliggör avbrott i de höga likströmmarna på extremt korta tider. Användandet av en Thomson-spole (TC, från engelskans Thomson Coil) för att generera höga drivkrafter anses vara en lämplig arbetsprincip för manöverdonet inuti CB. I detta projekt konstruerades ett koncept av ett mekaniskt manöverdon baserat på Thomson-spolen för SCiBreak AB, ett företag vars slutliga mål är att skapa en komplett ultrasnabb strömbrytare för HVDC-linjer. Designfasen mötte utmaningar med de höga krafter som krävs för att öppna ett gap mellan elektriska kontakter på bara några millisekunder. En detaljdesign för de olika komponenterna i manöverdonet utfördes och analytiska och CAD-modeller av systemet genererades. Projektet omfattade också tillverkning och provning av en prototyp i företagets lokaler. Slutprodukten var en analys och en diskussion av prototypens experimentella resultat samt förslag till framtida utveckling av det mekaniska manöverdonet.

As electronics are getting both smaller and more advanced, the need to verify and validate remains and the means are getting more complex the more functions and components are added. Traditionally, in-circuit tests (ICTs) are performed by probing dedicated test points on the Printed Circuit Board Assembly (PCBA) in a test sequence that is unique to each product. But as the density of components increases, the choice between component and test point must be considered. Instead of decreasing the reliability during verification by having to remove less system-critical test points, this thesis suggests the use of a near-field probe (NFP) based around a Giant Magneto-Resistance (GMR) sensor to possibly replace the need for a physical test point by instead performing contactless testing. The use of a GMR sensor allows for bandwidth from 0 Hz up to the MHz range, whereas commercial NFPs are based on a different technique and are operational from the MHz range and up. The goal of this project was to improve the non-linearity of typically 15% present in the AAH002-02 model from NVE by the use of an analogue closed-loop magnetic feedback circuit. The project successfully improved the linearity to 99.8% by the use of an instrumentation amplifier, a subtractor and a push-pull amplifier in conjunction with a 3x30 turn planar coil embedded in a PCB, located beneath the sensor Integrated Circuit (IC). The resulting linearity was verified by a Helmholtz coil where a uniform magnetic field was produced with linearly increased field strength, and calculated using the R2 value from a linear regression analysis on the acquired data. In the future, the data acquired from this kind of NFP could be used together with a Machine Learning (ML) model to remove the manual labour required when constructing these product-unique test sequences. / Dagens elektronik blir både mindre och mer avancerad, men behovet av verifiering och validering av dessa kvarstår och metoderna för detta ökar i komplexitet ju fler funktioner och komponenter som läggs till. Dagens kretskortstester genomförs genom att sondera dedikerade testpunkter strategiskt utplacerade på kretskortet enligt en testsekvens som är unikt skapad för varje produkt. Men med att densiteten av komponenter ökar måste valet mellan komponent och testpunkt tas i beaktning. Instället för att minska tillförlitligheten vid validering genom att ta bort mindre kritiska testpunkter föreslår denna avhandling användandet av en närfältssond baserad runt en Giant Magneto-Resistance (GMR)-sensor för att möjligen ersätta behovet av en fysisk testpunkt genom att istället genomföra kontaktlös testning. Användandet av en GMR-sensor tillåter en bandbredd från 0 Hz upp till MHzområdet, där kommersiella närfältssonder är baserade på annan teknik och är funktionsdugliga från MHz-området och uppåt. Målet med detta projekt var att förbättra olinjäriteten på typiskt 15% som är närvarande hos en sensor av modell AAH002-02 från NVE genom en analog magnetisk återkopplingskrets med sluten slinga. Projektet lyckades förbättra linjäriteten till 99.8% genom användandet av en intrumentförstärkare, en subtraherare och en push-pull-förstärkare i samverkan med en plan spole på 3x30 varv inbyggd i ett mönsterkort placerd under sensorns integrerade krets. Den resulterande linjäriteten validerades med hjälp av en Helmholtz-spole där ett uniformt magnetfält producerades med linjärt ökande fältstyrka och beräknades genom R2 -värdet från en linjär regression-analys på den inhämtade datan. I framtiden kan datan som inhämtats från den här sortens närfältssond kunna användas tillsammans med en maskininlärningsmodell för att ersätta det manuella arbetet som idag krävs för att konstruera dessa produktunika testsekvenser