In this work Reactive Power Planning (RPP) is studied. It is the method which aims at locating reactive compensators of optimal size at an optimal location in order to achieve or optimize a certain objective. In this work, the reactive compensators are placed in such away that they keep the voltages in a grid longer stable and within an acceptable range of values while power flows through the grid. Usually, this power flow disturbs the voltages. The RPP was applied in this work in order to allow a larger power flow from one grid area to another grid area. The first area is called the Source area and it contains generators which can produce power at a cheap price. The second area is called the Sink area and it is willing to import this cheap power so that it has to produce less power by itself. The two areas are connected to each other with a tie-line, which has a certain capacity (called Net Transfer Capacity or NTC). The capacity is restricted by stability requirements: exceeding the capacity would cause voltages to become unstable in either of the two grid areas. Installing reactive power compensators allows to increase the capacity of the line, keeping the voltages stable when the power flow over the tie-line increases. Reactive Power Planning therefore has an economic benefit, and different methods to optimize it will be investigated in this work. This work is divided into three parts. In the first part the relationship is studied between reactive power compensation on the one hand and the increase of the NTC of the tie-line on the other hand. The grid which is used to illustrate this is the Swedish grid, connected to the grids of Denmark and Finland. It is observed that not only increasing the loads can lead to voltage instability in the grid, but that voltage problems can also arise within the Swedish grid from the exchange of power,owing through the Swedish grid, between its neighbouring countries. It is shown that reactive power compensation is a technique which can potentially increase the NTC-value of the tie-lines between Sweden and Denmark and between Sweden and Finland. Depending on where the reactive power compensators are installed, the NTC increases with different values. In the next two parts however, we focus on the economic analysis of the reactive power compensation. In these two parts, an Optimal Power Flow (OPF) problem is designed, leading to the optimal placement and choice of the reactive power compensators. The optimal compensators increase the NTC so that the benefit of the decreased cost of power generationin the Sink area is maximized with respect to the cost of the reactive compensators. The difference between these two parts is in the algorithms that are applied for solving the OPF. In the second part a heuristic method based on a Genetic Algorithm (GA), NSGA-II, is used to optimize this benefit. The reason why first a heuristic method is used is that the NTC of the tie-line cannot be expressed as an analytical, closed-form function of the reactive power ratings. Therefore, a heuristic optimization method is chosen to solve the OPF and the algorithm NSGA-II is used because of its good convergence properties and ease of implementation. However, the algorithm is also able to perform multi-objective optimization and this ability is used to optimize both the economic benefit and the voltage stability index of the Sink area. It is seen that there is a trade-off between voltage stability and economic benefit and it is up to the grid operators to make choices regarding this trade-off. In the third part of this work a mathematical method is used to maximize the economic benefit of the Sink area with respect to the cost of the reactive compensators. As much as possible mathematical expressions will be used in this part. As the NTC cannot be expressed as a closed-form function, some approximations need to be made. Two methods were proposed to approximate the NTC: approximation by piecewise linear functions and by polynomials obtained with statistical regression. This mathematical method leads to a Voltage Stability Constrained OPF (VSCOPF). It is programmed in GAMS and formulated as a Mixed-Integer Non-Linear Programming problem (MINLP).

Today’s industry is moving towards a fourth revolution based on digitilizing technologies to reduce errors and streamline processes. When manufacturing hydraulicsand other pressurized systems, couplings are pressed onto pipes and hoses that mustbe able to maintain an expected pressure. If such a coupling has not been pressedcorrectly, there is a risk of leakage. This can have devastating consequences such asa liquid polluting the environment, inhalation of toxic gas, an important work stop,or a pilot losing control of an aircraft. Lantz Measuring AB therefore wants to develop a system that will be able to effectively ensure that these couplings have the correct shape around the entire couplingwith an accuracy of 0.1 mm. With this information, the manufacturer should beable to ensure that a coupling is correctly pressed. In this paper, a prototype for such a system has been developed as a contribution toa product that will meet Lantz Measuring’s requirements for accuracy, durability,and cost-effectiveness. The system is based on optical triangulation, which meanscalculating the line profile via the refraction of line lasers against the coupling usingimage sensors. Control and processing takes place with an FPGA and associatedperipherals.  The prototype shows that the requirement for trueness in the measured value is met,but that there is room for improved precision. Sources of error and methods thatcontribute to improved results are presented. The work describes the developmentof the system, testing of precision, and analysis of results. / Dagens industri rör sig mot en fjärde revolution som bygger på digitaliserande teknologier för att minska fel och effektivisera processer. Vid tillverkning av hydraulik ochandra trycksatta system så pressas kopplingar på rör och slangar som måste kunnahålla ett förväntat tryck. Om en sådan koppling inte har pressats fast korrekt såfinns det risk för läckage. Detta kan ge förödande konsekvenser genom att en vätskaförorenar omgivningen, inandning av giftig gas, ett viktigt arbete stannar av, elleratt en pilot tappar kontrollen över ett flygplan. Lantz Measuring AB vill därför utveckla ett system som effektivt ska kunna säkerställa att dessa kopplingar har rätt form kring hela kopplingen med en noggrannhetpå 0,1 mm. Med denna information ska tillverkaren kunna säkerställa att en koppling är korrekt pressad. I detta arbete har en prototyp för ett sådant system utvecklats som bidrag tillen produkt som ska uppfylla Lantz Measurings krav på noggrannhet, hållbarhet,och kostnadseffektivitet. Systemet baseras på optisk triangulering, vilket innebäratt beräkna linjeprofilen via brytningen av linjelasrar mot kopplingen med hjälpav bildsensorer. Styrning och processing sker med en FPGA och tillhörande kringutrustning.  Prototypen påvisar att kravet på riktighet i mätvärdet är uppfyllt, men att det finnsutrymme till förbättrad precision. Felkällor samt metoder som bidrar till förbättratresultat presenteras. Arbetet beskriver utvecklingen av systemet, test av precision,samt analys av resultat.

This bachelor's thesis is about developing a new imaging method for microscopy. The technique mainly involves two parts: implementing a variable stage that will move the sample and a fixed angle from which the camera will take the images. Earlier microscopy set-ups have used an auto-focus method where the pictures taken on the object have been taken vertically from above. The new process will not use auto-focus to maintain sharpness; instead, taking the images from a fixed angle will give rise to different focus levels. The variable stage will move to different positions on command for the camera to shoot the image area at all different focus levels and, to a later stage, be able to build up a large image based on optimal sharpness. The method uses a Laplace filter to localize the pixels with the greatest focus. After that, a row of pixels will be taken from every image to build up a new image. / Detta kandidatarbete går ut på att utveckla en ny bildtagningsmetod inom mikroskopi. Metoden innefattar främst två delar: implementering av ett mekaniskt steg som ska förflytta provobjektet, samt bildtagningar från en spetsig vinkel. Tidigare mikroskopiuppställning har använt sig av en autofokus-metod där bildtagningar av provobjektet har tagits från en rät vinkel istället. Den nya metoden kommer inte att använda sig av autofokus för att upprätthålla skärpa utan resultatet av att ta bilderna från en spetsig vinkel ger upphov till olika höjdskillnader i fokus istället. Det rörliga steget kommer att förflyttas till olika positioner så att alla bildytors fokushöjder kan fotograferas för att sedan bygga upp en enda stor bild baserat på optimal skärpa. Metoden använder sig av Laplace-filtrering för att hitta de pixlar i fokus och en algoritm skapas för att välja ut de pixlar i varje bild som sparas till en ny bild

The power grid companies must now review how to meet the increasing electrification in society. This report examines how the local low-voltage network in Karlstad will cope with an increased proportion of electric car charging in the home. With help from hourly measured values and high-resolution measured values, it is desired to study this. This study is intended to serve as a basis for future network planning and investments. By comparing measurements with different resolution and historical measurements, the load that electric car charging can cause on the grid is studied. The results show that the grid has the opportunity to meet the expected load. Problems can occur with 100% EV penetration, but with the help of support services and adjustments of the tariffs, a postponement of a grid expansion is possible.

This report presents a theoretical background to electromagnetic interference from photovoltaic systems that use power optimizers. The purpose is to carry out measurements at an existing facility to analyze and discuss appropriate measures to minimize disturbance levels. The work is designed by Glava Energy Center (GEC) and measurements are carried out together with the Swedish Electrical Safety Agency (Elsäkerhetsverket) and Rencke's El & Mätteknik. The report concludes with the results of measurement and a discussion of appropriate measures to achieve electromagnetic compatibility (EMC), designed for the specific facility. Finally, a brief discussion is given about future work in this area.

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When a fault is detected in the engine, the check engine light will come on. After that, it is often up to the mechanic to diagnose the engine fault. Manual fault classification by a mechanic can be time-consuming and expensive. Recent technological advancements have granted us immense computing power, which can be utilized to diagnose faults using data-driven classifiers. Data-driven classifiers generally require a lot of training data to be able to accurately diagnose system faults by comparing sensor data to training data because labeled training data is required for a wide variety of different realizations of the same faults. In this study an algorithm is proposed that does not rely on labeled training data, instead the proposed algorithm clusters similar fault data together by combining an engine model and unsupervised learning in the form of a modified Gaussian mixture model using Expectation Maximization. If one or more of the fault scenarios in a cluster is later diagnosed, the rest of the data in the same cluster is likely to have the same diagnosis. The modified Gaussian mixture model proposed in this study takes into account that residual data, in some cases including the case in this study when the data is from an internal combustion engine, seem to diverge from the nominal case (data points near the origin) along a linear trajectory as the fault size increases. This is taken into account by modeling the clusters as Gaussian distributions around fault vectors that each represent the trajectories the data moves along as the fault size increases for each cluster or fault mode. The algorithm also takes into account that data from one scenario are likely to belong to the same fault class i.e. it is not necessary to classify each data point separately, instead the data can be clustered as batches. This study also evaluates the proposed model as a semi-supervised learner, where some data is known. In this case, the algorithm can also be used to estimate the fault sizes of unknown faults by using the acquired fault vectors, given that there are known fault sizes for other data in the same cluster. The algorithm is evaluated with data collected from an engine test bench using a commercial Volvo engine and shows promising results as most fault scenarios can be correctly clustered. However, results show that there are clustering ambiguities for data from small faults, as they are more similar to the nominal case and overlap more with data from other fault modes.

Projektets mål var att utveckla en laboration för studenter i kursen Digitalteknik. För detta har en trafiksituation vid en vägkorsning använts som tema. Ett sekvensnät som styr trafikmiljön har programmerats i FPGA i Quartus på tillståndsdiagramsnivå. För att realisera projektet har DE1-SoC kretskortet valts. Laborationen är tänkt att skapa nya möjligheter för att bekanta studenter med moderna verktyg i digitalteknisk design som FPGA, VHDL-språket och Quartus programmeringsmiljö. Top-modulen i Quartus programmet har skapats på blockschemsnivå som tillåter ett överskådligt sätt att arbeta. En del extern hårdvara har kopplats till FPGA-kretskort så som servomotorer och LEDs. En modell av en vägkorsning med bommar, trafikljus och självkörande robot har skapats. Därigenom blev hela kedjan från problemformuleringen genom programmeringsdesignen och val, tillverkning och inköp av hårdvara till den fungerande trafikmiljömodellen genomförd. Detta resultatet kan illustrera digitaltekniksmöjligheter för studenter på ett tidigt stadium.

Electronics engineers rely on component tolerances to create functional designs. It isimportant to be aware that each component brings some uncertainty to the functionality ofthe assembly and therefore to the performance. To deal with this problem there are differentapproaches within the tolerance analysis field. Currently Veoneer uses the Worst CaseCircuit Analysis methodology that assumes that the worst scenario for every componentis possible, achieving very safe but pessimistic results. Electronics design can therefore beoptimized through statistical analysis.This work focuses on modelling the variance in the performance of a set of electroniccomponents that compose a device or assembly by means of statistical techniques. It usesdifferent methodologies to find models to explain the behaviour of these assemblies andit tests its results through different statistical tests to decide which one performs the best.From this point the work is focused upon finding the tolerance limits that are optimalfor the design while fulfilling safety requirements imposed by the automotive regulatorybody. The result obtained substantially improves the previousWorst Case Circuit Analysismodel while being as safe as required. This is a methodology that does not require of hugeamounts of data; making the process affordable for industry. Finally, it can be concludedthat statistical tolerance analysis can improve substantially the current results and boost thedesign of safety elements in electronics in the automotive industry while being as reliableas always.

In recent years, with the introduction of renewable energy sources (RES) and digital technologies, grids in Europe have become smarter.This is motivated by the need to effectively use the infrastructure incases of high penetration of RES. Consumer participation is one of the important features of smart grids. This customer participation can be individually controlled or collectively controlled by an aggregator. This thesis simulates a neighbourhood where each house is equipped with a photovoltaic (PV) system and a battery storage system such that each house is a net-zero energy building (NZEB). A comparison is made between the cost savings for the households when the battery is individually controlled and when an aggregator controls all batteries. The battery scheduling is optimized using genetic algorithm(GA). The results show higher savings in the case of aggregator control: the self-consumption (SC) increased with 4 percentage points, and the total energy costs for the whole neighbourhood was reduced by more than 40%. This thesis prepares the training data needed to implement the energy management system (EMS) using recurrent neuralnetworks (RNNs).