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In der vorliegenden Arbeit wird eine Methode zur Charakterisierung von Mikrosystemen mit beweglichen Komponenten dargestellt. Sie erlaubt, funktionsrelevante Parameter und deren Schwankungen produktionsbegleitend auf Waferlevel zu ermitteln. Dabei wird vorausgesetzt, dass die Sollform der Struktur und die Abweichungsarten bekannt sind. Die Methode beruht auf dem Vergleich von numerisch berechneten mit experimentell ermittelten Eigenfrequenzen der untersuchten Mikrosysteme. Dazu wird die Abhängigkeit verschiedener Eigenfrequenzen von den gesuchten Parametern mittels einer Parametervariationsanalyse berechnet und durch eine geeignete Funktion angenähert. Die Messung der dynamischen Eigenschaften erfolgt mit Hilfe eines Bewegungsanalysators, der auf einem Laser-Doppler-Vibrometer basiert. Im letzen Schritt werden die gesuchten Parameter berechnet. Kernpunkt der entwickelten Methode sind Messungen auf der Basis von speziellen Teststrukturen, die im Waferlayout neben den eigentlichen Nutzstrukturen platziert sind und parallel mit den Nutzstrukturen prozessiert werden. Es werden Algorithmen zur Generierung des Designs der Teststrukturen und ihrer Platzierung im Waferlayout entwickelt. Dabei werden das Design der Nutzstruktur und deren funktionsrelevante Parameter, der technologische Ablauf und materialspezifische Kennwerte berücksichtigt. Im Ergebnis liegt eine Bibliothek von Standard-Teststrukturen vor, die für produktionsbegleitende Messungen sowie für die Übertragbarkeit der Ergebnisse geeignet sind. Außerdem werden allgemeingültige Richtlinien zur Durchführung der Messungen an den Standard-Teststrukturen abgeleitet. Das Messverfahren wurde an unterschiedlichen Mikrosystemen mit beweglichen Komponenten überprüft und zu einer allgemeinen Messmethode für diese Klasse von Mikrosystemen erweitert. / In this work a method for the characterization of microsystems with movable components is presented. The method allows to determine the relevant parameters and their variations on wafer level if the nominal shape of the structure and the type of deviations are known. The method is based on a comparison of the numerically calculated and experimentally measured Eigenfrequencies of the microsystems. For that purpose, the relationships between various Eigenfrequencies and the searched parameters are calculated by parameter variation analysis and the results of this analysis are approximated with appropriate functions. A Laser Doppler vibrometer based motion analyzer is used to determine the frequency response function of the micromechanical structure and extract Eigenfrequencies. The comparison of the measured and the calculated frequencies provides values for the searched parameters. The key element of the developed method is the measurement on special test structures that are placed in the wafer layout next to the actual microsystems and processed in the same technological process parallel to the actual microsystems. Algorithms for designing the test structures and their placement in the wafer layout are shown, taking into account the design of the actual microsystems and the function parameters of the technological process as well as material characteristics. As a result, a library of standard test structures for function relevant parameters is available. A general guideline for the measurement on the test structures is presented. The presented method is verified on various microsystems and extended to a whole class of microsystems with movable components.

Vevaxeldeformation studeras i samband med uppspänning i en virvelfräsmaskin inför en skärande process. Syftet är att öka förståelse om deformationsbeteendet av vevaxelns viktiga funktionsytor genom analysering med Finita elementmetoden (FEM). Volvo Cars i Skövde hanterar i dagsläget oönskad vevaxeldeformation genom tidskrävande fysiska tester. Därför önskar företaget ta stöd av virtuell analysering. Detta arbete leder även till ett fastställande om FEM är ett tillämpbart verktyg att utgå ifrån för att upprätthålla snäva vevaxeltoleranser. Användning av virtuell analysering istället för fysiska tester skulle medföra tidsbesparing och ha positiv inverkan på miljön.  Programvaran Abaqus används för genomförande av deformationsanalyser vilka också utvärderas mot fysiska mätningar i en dragprovmaskin (Instron) för att därigenom säkerställa pålitligheten av använd FE modell.  Analyser genomförs huvudsakligen för deformationsuppkomst av vevaxeln i samband med uppspänning. Två olika typer av vevaxlar analyseras. Till respektive vevaxel skapas en FE modell med ansatta randvillkor och belastningsförhållanden utgående från en genomförd mekanisk analys av vevaxeln. Erhållna resultat visar att bricksidorna av vevaxeln deformeras med i storleksordningen <img src="http://www.diva-portal.org/cgi-bin/mimetex.cgi?10%5E%7B-2%7D" /> mm då vevaxeln belastas i samband med uppspänning med en hoptryckning på 0,2 mm. Denna deformation anses medföra risk att ett bearbetningsfel kan förorsakas. Analyserna visar även vilka ytor som deformeras mest/minst. Utvärdering mot dragprovning indikerar att riktning på vevaxeldeformation stämmer överens med analyserna, men att avvikelser på deformationsstorleken förekommer. Skillnaden kan möjligen förklaras med att E-modulen varierar inom den testade vevaxeln medan den definierade E-modulen i Abaqus antar ett konstant värde. Dessutom kan eventuella felkällor från dragprovningen ha inverkan på resultatutfallet av de fysiska mätningarna.  Genomförda analyser tyder på att FEM är tillämpbar för analysering av vevaxeldeformation och rekommendationer om en lämplig FE modell tillhandahålls. En potentiell lösning till deformationsproblemet anses vara beräkning av optimal klämkraft vid uppspänning. / Crankshaft deformation is studied in connection with clamping conditions in a whirl milling machine before a cutting process. The purpose of the project is to increase knowledge about the deformation behaviour of the crankshaft and its important functional surfaces by performing analyses using the finite element method (FEM). Volvo Cars in Skövde, Sweden is currently managing unwanted crankshaft deformation occurrence by using time consuming physical testing methods. Therefore, the company wish to use virtual analyses instead of physical tests. This work also leads to a determination if FEM is an applicable tool in order to maintain narrow tolerances of the crankshaft. Using virtual analyses instead of physical tests would be time saving and would also have a positive impact on the environment. The computer software Abaqus is used to implement the deformation analyses that are also evaluated against physical measurements done with a tensile testing machine (Instron) and thereby be able to ensure the reliability of the used FE model. FE analyses are mainly performed to evaluate the deformation of the crankshaft associated with clamping. Two different crankshaft types are being analysed. A FE model is created for each crankshaft along with applied boundary and load conditions according to performed mechanical analysis of the crankshaft. Obtained results show that the thrust bearing sides of the crank pins on the crankshaft deform in the range of <img src="http://www.diva-portal.org/cgi-bin/mimetex.cgi?10%5E%7B-2%7D" /> mm when the crankshaft is compressed during clamping with 0.2 mm. This deformation is considered to entail a risk for a processing error to occur. At the same time the analyses show which surfaces are most/least deformed. Evaluation according to the tensile testing indicates that the direction of the crankshaft deformation corresponds to the analysis but slight deviation of the deformation magnitude is present. The deviations can be explained by variations of the E-module within the crankshaft while the defined E-module in Abaqus has a constant value. Furthermore, there is a possibility that sources of error from the tensile tests can have an influence on the obtained results from the physical measurements. Conducted analyses indicates that FEM is applicable for crankshaft deformation analyses and recommendations of a suitable FE model are provided. A potential solution of the deformation problem is considered to be the calculation of optimal clamping force.

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This paper describes the design, fabrication, and testing of a 1.2 kV, 6.5 mΩ, half-bridge, SiC MOSFET power module to evaluate the impact of parametric device tolerances on electrical and thermal performance. Paralleling power devices increases current handling capability for the same bus voltage. However, inherent parametric differences among dies leads to unbalanced current sharing causing overstress and overheating. In this design, a symmetrical DBC layout is utilized to balance parasitic inductances in the current pathways of paralleled dies to isolate the impact of parametric tolerances. In addition, the paper investigates the benefits of flexible PCB in place of wire bonds for the gate loop interconnection to reduce and minimize the gate loop inductance. The balanced modules have dies with similar threshold voltages while the unbalanced modules have dies with unbalanced threshold voltages to force unbalanced current sharing. The modules were placed into a clamped inductive DPT and a continuous, boost converter. Rogowski coils looped under the wire bonds of the bottom switch dies to observe current behavior. Four modules performed continuously for least 10 minutes at 200 V, 37.6 A input, at 30 kHz with 50% duty cycle. The modules could not perform for multiple minutes at 250 V with 47.7 A (23 A/die). The energy loss differential for a ~17% difference in threshold voltage ranged from 4.52% (~10 µJ) to -30.9% (~30 µJ). The energy loss differential for a ~0.5% difference in V_th ranged from -2.26% (~8 µJ) to 5.66% (~10 µJ). The loss differential was dependent on whether current unbalance due to on-state resistance compensated current unbalance due to threshold voltage. While device parametric tolerances are inherent, if the higher threshold voltage devices can be paired with devices that have higher on-state resistance, the overall loss differential may perform similarly to well-matched dies. Lastly, the most consistently performing unbalanced module with 17.7% difference in V_th had 119.9 µJ more energy loss and was 22.2°C hotter during continuous testing than the most consistently performing balanced module with 0.6% difference inV_th. / Master of Science / This paper describes the design, construction, and testing of advanced power devices for use in electric vehicles. Power devices are necessary to supply electricity to different parts of the vehicle; for example, energy is stored in a battery as direct current (DC) power, but the motor requires alternating current (AC) power. Therefore, power electronics can alter the energy to be delivered as DC or AC. In order to carry more power, multiple devices can be used together just as 10 people can carry more weight than 1 person. However, because the devices are not perfect, there can be slight differences in the performance of one device to another. One device may have to carry more current than another device which could cause failure earlier than intended. In this research project, multiple power devices were placed into a package, or "module." In a control module, the devices were selected with similar properties to one another. In an experimental module, the devices were selected with properties very different from one another. It was determined that the when the devices were 17.7% difference, there was 119.9 µJ more energy loss and it was 22.2°C hotter than when the difference was only 0.6%. However, the severity of the difference was dependent on how multiple device characteristics interacted with one another. It may be possible to compensate some of the impact of device differences in one characteristic with opposing differences in another device characteristic.

Spritzgießbare Duroplaste zeichnen sich durch hohe thermo-mechanische Beständigkeit, geringe Schwindung und niedrige Materialkosten aus. Damit können die Anforderungen an spritzgegossene Präzisionsbauteile für den Automobilbau erreicht werden. Im Rahmen der vorliegenden Arbeit werden unterschiedliche Novolak-Phenolformmassen hinsichtlich ihres hygroskopischen Verhaltens und dessen Auswirkung auf die Spritzgießverarbeitung und die Bauteilqualität untersucht. Das Absorptionsverhalten kann mithilfe der Fick’schen Diffusionsgesetzte näherungsweise beschrieben werden. Auf Basis von mechanischen Untersuchungen sowie der Beurteilung der Maßhaltigkeit eines Präzisionsdemonstrators hinsichtlich Schwindung und Verzug wird zudem der Einfluss der Prozessparameter beim Spritzgießen bestimmt. Die vorgestellten Untersuchungen zeigen die Grenzen der Verarbeitung und der realisierbaren Bauteilqualität auf, die auf die großserientaugliche Verarbeitung von duroplastischen Bauteilen übertragen werden können. / Injection moldable thermosetting materials show excellent material properties, e.g. high thermo-mechanical resistance and reduced shrinkage in combination with low material cost. Thus, technical requirements for high performance parts for automotive applications can be achieved. In the scope of this work different phenolic novolac compounds were investigated regarding their hygroscopic behavior with its influence for injection molding and product quality. The absorption can be approximately described by Fick’s-Diffusion-Model. The interrelationship of injection molding parameters and the thermo-mechanical behavior is examined on the basis of mechanical testing and the assessment of the dimensional accuracy for a thermoset high precision part. The presented investigations point to the limit of processing and realizable part quality which can be transferred for high performance parts molded in mass production.

Electrical connectors are the blocks that connect solar panels together. Whenever a photovoltaic plant commences, the main discussion goes around on solar panels, inverters, charge controllers, etc. But the topic of connectors is usually hardly discussed. Connectors in a photovoltaic system can definitely contribute to improve the overall performance of the system, provided that importance is given while selecting the connectors. The electrical connectors used in photovoltaic systems can be connected in two possible ways. Connectors can be connected either in a pure-connection or in a cross-connection. Male and female connectors from the same brand results a pure-connection (P-C). Male and female connectors from two different brands results in a cross-connection (C-C). There have been discussions in photovoltaic, electrical connector markets and international solar events regarding the risks involved, losses and consequences due to a cross-connection. The main reason behind cross-connections is the unawareness of the installers in knowing the difference between a pure-connection and a cross-connection. Even though the installers are aware of this difference, they are not aware of the consequences of cross-connections. Multi-Contact, a leading electrical connector manufacturer of MC4 photovoltaic connectors affected by the counterfeit products of MC4, due to the sudden boom in the solar market during 2011-12. With the help of TÜV Rheinland, Multi-Contact conducted couple of tests namely temperature increase test and accelerated stress tests to understand the disadvantages of cross-connections. This thesis tried to replicate the tests performed by Multi-Contact in an attempt to understand the test results by using connectors that are used in the Swedish market. Performing temperature increase test and accelerated stress tests on most commonly used connectors in the Swedish market is the main aim of this thesis. The first test, gives an understanding of the temperature variations across various connector sets (four connector sets from various manufacturers used in this thesis) and the latter tests helps to understand the quality of the contact resistance of these connector sets. The four connector set manufacturers used in this test were Multi-Contact (MC), Weidmüller (WM), Blussun solar (BSS) and PBM. The quality of contact resistance of a connector is directly related to the quality of the connector set. During the 20 minutes of the temperature increase test, the connector set from WM performed better than its competitors in the P-C. Whereas, the MC-BSS connector set had performed well in the C-C. The connector type of male MC and female BSS showed its dominance throughout the test. Unfortunately, no conclusions were able to be drawn from this test results due to insufficient information about the test procedure. From the results of accelerated stress tests, the C-C set from MC outperformed its P-C counterpart. All ten connector sets used in this project passed the standard and qualified as connectors with good quality contact resistance. Therefore the best results out of only a P-C connector set does not seems to be completely true. With the standard used in this thesis, it is quite difficult to judge the quality of connectors. Rather than saying a P-C is superior and a C-C is inferior in terms of quality, there is a need to come up with a new method to evaluate the quality of connectors. Matching the connectors based on their tolerances could be a potential solution to the mismatching problem in connectors.

This assignment is based on the tolerance problems that occur with the radial dimensions or RR-dimensions for the windings. The purpose is to identify the various parameters that affect said RR-dimensions and where these parameters originate from to be able to assure quality of the winding process. The RR-dimension has a tolerance of + 2,2 and - 1,1 mm, but it is only the positive tolerance that cause problems. The case study is based on a mixture of quantitative and qualitative methods. Quantitative data collections of dimensions for leaders and how the RR-measurement are affected by them, analysis of tolerances and how well they are adapted for their purpose. Qualitative observations, experiments and semi-structured interviews have also been conducted to gain a deeper understanding of the problem. The results show that tolerance problems originate from several different factors. The first factor is the debatable tolerance setting on some conductors, mainly the thin CTC conductors that do not have a high radial dimension. These conductors have tolerances that do not fill a purpose because it does not ensure the quality for the winding. The conductors need a tighter tolerance spectrum for the positive direction to be fully functional. The air gap that can occur between the conductors is also a cause of error. This stems from the fact that it is not possible to achieve a sufficiently high force when tensioning the disc. This can also occur from the uneven surface of the CTC-conductor that can create gaps. Another cause of error that affects the dimension is the number of turns for a disc. When a disc is wound with a high number of turns it will lead tothat the influencing factors have a higher amount of turns to effect on. This means that a small increase of the conductor's nominal dimension or small air gaps has a large impact on the overall RR-dimension. / För att kvalitetssäkra transformator- och reaktorlindningarna hos företaget Hitachi ABB skade utsatta toleranserna för varje lindning uppfyllas för att kunna fortsätta vidare i produktionslinan. Arbetet är grundat utifrån de förekommande variationerna hos lindningarnas mått i radiell riktning (RR-mått. Arbetets syfte är att undersöka Hitachi ABB:s lindningsproduktion för att finna de faktorer som ger upphov till måttvariationer hos RRmåttet. De identifierade faktorerna ska användas för att kvalitetssäkra företagets lindningsprocess. Färdigställt arbete ska användas som grund för företagets fortsatta arbetekring kvalitetssäkring. RR-måttet har en tolerans på + 2,2 och – 1,1 mm, däremot är detendast de variationer i positivt led där problem uppstår. Vid ett för högt mått genomförs enutredning för att se över om lindningen kan brukas ändå eller utifall de för höga måttet i radiell riktning påverkar prestandan samt montering. Arbetet är en fallstudie utfört med en blandning av kvantitativa och kvalitativa metoder. Denkvantitativa datainsamlingens syfte är att undersöka ledares mått i lindningar för att se hur RR-måttet påverkas måttsättning och varvantal. Den kvantitativa datainsamlingen genomför också analyser av toleranser och hur väl anpassade de är för sitt syfte. Kvalitativa observationer, experiment och halvstrukturerade interjuver har genomförts för att skapa en djupare förståelse kring problemet.Resultatet visar att de variationer som uppstår hos RR-måttet påverkas av flera olika faktorer.Variationer hos RR-måttet uppstår främst för lindningar där en CTC-ledare används. En påverkande faktor är toleransvidden för ledarna, främst för de tunna CTC-ledarna. Ledarna lindas runt varandra där ledarens mått staplas på varandra för att bilda ett RR-mått. För de tunna CTC-ledarna bör en mindre toleransvidd användas, mer specifikt en lägre positiv tolerans likt de platta ledarna för att kunna kvalitetssäkra lindningen. En annan påverkandefaktor är de luftspalter som uppstår mellan ledarna. Luftspalter härstammar ifrån att det integår att uppnå tillräckligt hög kraft vid spänning av en skiva alternativt från CTC-ledarens knöliga yta. Utöver dessa två faktorer har antalet lindade varv för en skiva en påverkan förtoleransstapling. Fler varv resulterar i att små måttavvikelser för ledare påverkar det totala måttet, vilket innebär att de luftspalter som kan uppstå blir fler när antalet varv ökar.

This diploma thesis deals with location optimal wavelet for detecton charakterics points of QRS complex in ECG signals. The first part of this thesis deals with description of heart, genesis of electric signals on heart and problem of noise. The second part describes the wavelet transform and the designed program and the third part evaluate detection results. The created program is working with 10 ECG signals from the CSE database and is testing 12 different mother wavelets. The program was developed in Matlab environment and is based on the finding zero-points in the transformed signal.

A nominal setup at Volvo Cars Corporation is the placement determination for two adjacent exterior parts on the car. To place the parts in optimal positions, nominal values for gaps and flushes are determined. When a nominal setup becomes more complex, VSA (Vehicle System Architect) is summoned. These appearing situations regard the involvement of several attributes and the need for a combination of vari- ous contributions. There are static, dynamic (overslam or dynamic movement) and thermal contributions that are combined into nominal values of gap and flush dis- tances. The determination process of a nominal setup contains both calculation for each contribution, as well as the combination method which takes place at the VSA meetings. This Master Thesis project consists of the development of an improved determination process for nominal setups. The current determination process has a low level of transparency within the differ- ent group’s methods. Another issue is the insecurity of the probability estimations made when combining the contributions. Therefore, the focus of the project was to infuse a greater understanding of the contribution derivations, and greater insight into the probability of the taken risks. To achieve that, the project was divided into three parts; mapping of the determination process, individual contribution improve- ments and finally, improvements to the combination method. In contemplation of improving a process, plenty of knowledge needs to be gathered, regarding methods, simulations and possibilities. This was executed by interviewing experts within spe- cific areas at the different groups at VCC. Development of the improvements was done by interviews and various studies. It was shown that the mapping of the determination process increased the trans- parency between the groups as it increased the understanding of individual groups’ work. Contribution improvements lead to more realistic load cases used for dimen- sioning. A performed overslam clinic, where closing velocity data of a tailgate were collected, lead to a greater statistical base for which load case should be used. For dynamic movement, another method is proposed that considers relative movement instead of applied accelerations. For the thermal contribution, the approach of ge- ographically gathered temperature data was proposed. The improved combination method generates combinations with regard to three input values instead of one, from each contribution, to create different combination scenarios. The probabilities of the scenario occurrences are estimated which gave VCC a greater understanding of what risks that are taken. Furthermore, the combination method also educates the VSA meeting attendees by exhibiting the derivations and bases for each contri- bution.