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  • 1.
    Abbas, Mohamed
    University West, Department of Engineering Science, Division of Industrial Engineering and Management, Electrical- and Mechanical Engineering.
    Småskaliga elproduktionskällor som bygger på förnyelsebar energi lämpliga för installation i städer eller tätorter2021Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This study maps several different small-scale and renewable electricity generation plants that are suitable for installation in the urban environment such as solar panels, wind turbines and water reactors. The thesis is studying the conditions and potential for these power sources to be installed and operated in residential areas.

    The premise covers how these facilities work, the factors affecting different facilities and the number of uses in the urban environment. The premise also includes a couple of investment cost analyzes for solar and wind power. The profitability analysis contains an economic comparison between wind or solar power and ordinary electricity from electricity companies.

    The thesis shows how profitable it is for a medium-sized house with an annual consumption of about 16,000 kWh to install solar cells or a small wind turbine, where all revenues such as state aids and surplus sales are counted towards payments such as investment costs.

    The result from the profitability analysis indicates that it is more profitable to invest in renewable production plants than to buy ordinary electricity from electricity companies. Profitability is beneficial for private individuals and society.

  • 2.
    Abdallah, Ali
    et al.
    University West, Department of Engineering Science, Division of Industrial Engineering and Management, Electrical- and Mechanical Engineering.
    Yosef, Janan
    University West, Department of Engineering Science, Division of Industrial Engineering and Management, Electrical- and Mechanical Engineering.
    Elbilsladdning längs E62021Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    In Sweden, there are about 220,000 electric cars and the goal is to have 2.5 million electric cars by 2030. To achieve the goal, the charging infrastructure in Sweden needs to increase, especially along the motorways. The task is to investigate the possibility of expanding the charging infrastructure on the E6 between Gothenburg and Malmö. The chosen location for installation of a charging station along the E6 between Gothenburg and Malmö is at Heberg outside Falkenberg. This locationis suitable since it has a large parking lot and a restaurant where potential customers can rest and eat food while their electric car is being charged. There are different types of electric cars, plug-in hybrids and pure electric cars. 71% of all electric vehicles are plug-in hybrids while 29% are pure electric cars. Plug-in hybrids have an electric motor and a fuel engine while pure electric cars only have an electric motor. About 25.000 cars travel on the E6 at Heberg daily and about 4% of these are electric cars, and therefore it is estimated that about 50 electric cars per day will be charged at the selected location. The installation consists of 6 charging stations at Laxbutiken in Heberg, two fast chargers and four semi-fast chargers. The fast chargers are Terra 184 CC with an output of 180 kW and can charge up to three cars simultaneously. The semi-fast chargers are Chargestorm Connected 2 with two charging points for each pole and a power of 22 kW. Fast chargers can charge a car in 20-30 minutes, while with a semi-fast charger it takes 1-2 hours. The charging time depends on the size of the battery and the power. The total power required for the charging posts is 448 kW. A substation will be installed with an 800 kVA transformer to ensure that expansion is possible in the future without replacing the transformer. The cables are also dimensioned so they can also handle a future power increase. The cost of the project will be approximately SEK 1.856.000 including materials, cables and charging stations. The expected income is approximately SEK 894.000 in the first year. Payment terminals will be rented and installed at each charging station at a cost of SEK 85.740 including rent and transaction fees. With 50 % financial support from klimatklivet, the investment will be paid back within 1.1 years.

  • 3.
    Abdallah, Houda
    et al.
    University West, Department of Engineering Science.
    Saleh, Najat
    University West, Department of Engineering Science.
    Cyberattacks through Stegomalware2022Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Stegomalware is a type of malware that utilizes steganography to evade detection. It hides amalicious code inside an innocuous cover medium. The cover medium could be of any type: image, audio, video or even network protocols. Stegomalware has also shown to be a highly effective method to bypass detection. This has led it to increase in popularity among cybercriminals. In this thesis, the aim is to shed light on these cyberattack techniques and show the potential harm that could impact organizations, people, and transmitted data over the network. This is done by exploring the following: state of the art, the use of malware steganography in cyberattacks, most used techniques, and how to defend against them. The prevalent tools used by cybercriminals along with various existing stegomalware prevention and detection techniques have been surveyed and studied. A practical implementation was done with the purpose of observing the technical process that takes place at the point of data hiding. In total two tests were done, with both using the Least Significant Bit (LSB) algorithmto achieve the desired results. 

  • 4.
    Abdallah, Hussein
    et al.
    University West, Department of Engineering Science, Division of Industrial Engineering and Management, Electrical- and Mechanical Engineering.
    Gustafsson, Robin
    University West, Department of Engineering Science, Division of Industrial Engineering and Management, Electrical- and Mechanical Engineering.
    Elbilsladdning längs vägen Trollhättan-Sälen2021Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The number of electric cars has increased drastically in recent years and interest in renewable energy is growing. In addition, the need for good charging infrastructure on the roads, which is sufficient for all new electric cars, is also increasing. This thesis is about placing charging infrastructure along the road Trollhättan-Sälen. 

    The report contains information about the different types of electric cars that currently exist with different safety levels and contact types. Different methods are used to calculate the range of electric cars. The report also contains information about the rules and laws that apply when installing charging stations.

    To find out where new charging infrastructure is needed on the route, a study is made of how many electric cars that travel on the specific roads each day. This is done to produce an estimate of the need for charging stations. However, it is difficult to know how long the cars need to be charged as there are large differences in the capacity of electric cars depending on which model it is. Also, not everyone stays the same time or charges until the battery is full. 

    Other studies were also carried out before the work began to get a better understanding of the conditions that exist on the section Trollhättan to Sälen. It is important to place the charging stations where new charging infrastructure is actually needed. Åmål, Sunne and Limedforsen were chosen based on the investigation done before placement. 

    Several companies were contacted during the project, although it was only one company that could state the prices of the products. Therefore, ABB was chosen as the supplier and prices for charging stations come from ABB. EBRE's cost calculation is used to obtain the prices for the substation, transformer, shaft and cable, etc. 

  • 5.
    Abdalrhman, Slah Aldeen
    University West, Department of Engineering Science, Division of Production Systems.
    Virtual model of a production process: Seam sealing line at Scania2019Independent thesis Advanced level (degree of Master (One Year)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    The concept of digital factories is becoming more popular among the manufactures due to its contributions in simplifying the work of plant engineers and reducing time to market of the products [1]. The main aim of this thesis was to investigate the possible applications of a digital copy of production processes by creating a virtual model of a seam sealing line in the paint department at Scania in Oskarshamn. The main usage of the virtual model was to perform offline programming of the robots. The benefits of offline programming were investigated and compared to online programming. Some comparisons between offline and online programming were made when it comes to the time needed for programming, the accuracy of generated robot paths, the workflow of both approaches and the required knowledge to turn from online programming to offline programming.

    The result of the conducted experiment showed that the time of robot programming can be reduced, and the accuracy of robot paths increases by implementing an offline programming tool. The other application of virtual which was investigated in this thesis was virtual commissioning. Virtual commissioning is a method used to test and validate robot and control (PLC) programs in a virtual environment before implementing in the real plant. The software in the loop was selected as an approach for building the virtual commissioning model after presenting the different existed approaches. The result of the model showed great benefits of virtual commissioning not just in reducing the time of traditional of the new built line but even when replacing parts in an already existing manufacturing. Virtual commissioning is still new in the manufacturing, therefore, there are many issues which should be solved to get an optimal model that imitates perfectly the real plant.

  • 6.
    Abdi, Abdurazak
    et al.
    University West, Department of Engineering Science.
    Omar, Hassan
    University West, Department of Engineering Science.
    Undersökning av två faktorer autentiseringsmöjligheter för inloggning till Linux-server samt Microsoft-Azure MFA2023Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Två-faktorautentisering är en tvåstegsverifieringsprocess som syftar till att ge ytterligare säkerhetsnivå genom att kräva att användaren verifierar sig med hjälp av en sekundär metod,för att säkerställa att personer som försöker få tillgång till ett online-konto är rätt person och utan 2fa kan hackare få tillgång till känslig information eller konto enbart genom att känna till offrets lösenord.I denna studie kommer mest använt 3 olika alternativa två faktor autentiseringsmöjligheter för inloggning till Linux servrar undersökas för att se vilken 2fa som är både användarvänlig och säker att använda. Faktorer som kommer att undersökas är kostnad, plattformskompatibilitet, tillförlitlighet, säkerhetsmässigt och tid samt backupalternativ.undersökningen kommer vara baserat på intervjuer om Högskolan Västs IT avdelnings nya två faktor autentiseringssystem för anställda. Det kommer ställas frågor till systemspecialist som har tagit fram två faktorer autentiseringslösningen och Högskolans anställda som kommer använda azure mfa lösningen. Frågorna kommer vara baserad anställdas behov av två faktor autentiseringssystem och hur de anställda upplever den nya två faktor autentiseringslösningen.Resultaten från de praktiska testerna påvisar att Yubikey var den mest säkra autentiseringsmetoden och duo var den mest användarvänliga metoden. Resultaten som samlats från intervjuerna visade att anledningen till att Högskolan Västs IT-avdelning vill implementera två faktorer autentiseringen var att skydda mot Phishing attacker som kan vara svåra att upptäcka

  • 7.
    Abdo, Adel
    et al.
    University West, Department of Engineering Science, Division of Industrial Engineering and Management, Electrical- and Mechanical Engineering.
    Tesfai, Henon
    University West, Department of Engineering Science, Division of Industrial Engineering and Management, Electrical- and Mechanical Engineering.
    Öka energieffektiviteten genom Industri 4.02021Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This bachelor’s thesis has been carried out in consultation with PTC in Trollhättan, Sweden. The report consists of a comprehensive literature study on the various aspects involved, Reduce electricity waste by Industry 4.0. The various aspects concerning “Reduce electricity waste by Industry 4.0” have been investigated and a decision was made by the authors that by understanding the various aspects within the relevant subject, a deeper understanding will exist when the result is demonstrated. The various aspects are basic information about Industry 4.0, preventive maintenance, general knowledge about ventilation, minimizing the temperature increase and reducing energy consumption in an industrial premises with the help of ventilation and an information section about the lithium ion battery. 

    Finally, a result has been produced for crushing and the separation room to reduce the energy consumption in the room. The result consists of two parts in the same solution. The two steps are by reusing the air in the room as much as they can reduce the energy consumption in having to heat or cool the new external air. The second step is that with the help of AI and Big data technology, the computer system that controls the ventilation system will learn and recognize patterns of the weather and temperature in the external environment outside the industrial premises. Once the computer system has learned this, it can implement the lesson of when it is time for new external air to replace the existing air in the room and when it is time to try to reuse the air in the room to reduce energy consumption in heating and cooling the air. 

    Through personal communication with the supervisor Johan Dahlström a result has been produced by the authors. Results are considered to achieve the goal of reducing energy consumption with the help of Industry 4.0.

  • 8.
    Abdulkareem, Haji  
    et al.
    University West, Department of Engineering Science, Division of Industrial Engineering and Management, Electrical- and Mechanical Engineering.
    Javidan, Mustafa
    University West, Department of Engineering Science, Division of Industrial Engineering and Management, Electrical- and Mechanical Engineering.
    Nätutvecklingsplan för området Hälltorp i Trollhättan2019Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    After many long power failure occurrences on the overhead line that feeds the receiving substation Torsred, and because of the household expansion in nearby area, Trollhättan Energi Elnät AB has decided that a new receiving substation that replaces the existing one should be built at a new location. This thesis includes investigation and calculation of a new electricity network and suggestions on how the new electricity network can integrate with the existing one. Also, a new selective coordination plan and new backup power alternatives are investigated.

    The existing receiving substation Torsred is fed by Vattenfall Eldistribution AB:s 130/10 kV transformer OT00 by an 1 km long overhead line. The neutral point in Torsred is connected to the high voltage bar and consists of neutral grounding resistor and neutral point reactor. The total load current in Torsred is 925 A and during short-circuit in the busbar 154 MVA short-circuit power emerges. The substation Ängen with a short-circuit power 138 MVA is an underlying substation to Torsred that feeds the areas Öresjö, Edsäter and Hjärtum. All the outgoing electric lines in Torsred and Ängen are protected with relay protection and with different time- and current setting on these relays is selectivity installed for the underlying electrical network.

    The new receiving substation is planned to be built near the feeding point OT00. According to calculations the short-circuit power in the new receiving substations will be 227 MVA and in Ängen 200 MVA. The capacitive current increases because the over 1 km overhead line is demolished, and additional 7,5 km underground cable is added on in the new electrical network. A neutral point reactor needs to be upgraded to a 20 A bigger than the existing one because of the increasing capacitive generation in the electrical network. The price to build the receiving substation will be about 9 Mkr. The existing receiving substation Torsred will be demolished and replaced with a new 800 kVA network substation which will be used to feed a couple of the low voltage network in the area Strömslund. The distribution substation Ängen will be modernized. The total price for the whole project is calculated to 11,4 Mkr.

    Download full text (pdf)
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  • 9.
    Abolhanna, Hussein
    University West, Department of Engineering Science.
    Jämförelse av toppeffekten mellan nätstationsmätare och Velanders formel2023Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Elnätet dimensioneras för att klara årets största effekttoppar. Det är viktigt att överväga sammanlagringen mellan flera kunder, eftersom individuella kunders effekttoppar skulle ge felaktiga uppskattningar av nätstationens högsta förbrukning. Idag finns det timinformation om varje nätstations förbrukning, vilket inte fanns tidigare. Tidigare uppskattades storleken på effekttoppar i nätstationen från den årliga förbrukningen för uppkopplade kunder enligt den så kallade Velanders formel. För att utvärdera denna uppskattning av toppeffekten jämfördes nätstationens och underliggande kunders timförbrukning med de effekter som beräknats med denna formel. Resultatet av jämförelsen visade att formeln i vissa stationer överskattade eller underkastade storleken på den förväntade toppeffekten. Det förändrade energi-till-effektförhållandet på grund av laddning av en elbil gör att nya Velanderkonstanter behöver tas fram för hushåll med elbilsladdare. För att kunna göra dettaär det även viktigt att elnätsföretagen får information om montering av laddboxar och dess maximala laddeffekt. Historisk har elnätet ofta överdimensionerats, till stor del på grund av osäkerheten om förväntad förbrukningen och den ofta relativt låga kostnadsökningen medatt välja en grövre kabel i samband med utbyggnad av elnätet. Med elektrifieringen av fordonsflottan och produktionen av el med solceller hos konsumenter ökar belastningen på lågspänningsnäten och inmatning kan förekomma till nätstationer. Genom förbättrad mätning i nätstationer kan skillnaden mellan verkliga toppeffekten och dimensionerad maximal effekt minskas. Detta i sin tur kan minska behovet av nyinvestering i nätet för att klara energiomställningen. 

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  • 10.
    Abudaher, Mohammed
    et al.
    University West, Department of Engineering Science, Division of Computer and Electrical Engineering.
    Alomari, Kamal
    University West, Department of Engineering Science, Division of Computer and Electrical Engineering.
    Energieffektivisering i köpcentret Sisjö Entré i Göteborg2014Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Energy efficiency means that energy is used in an efficient way that impacts positively on the environment and society.

    Sisjö Entré is a shopping center which has an annual energy consumption of 1 865 270 kWh, and according to Energy Authority, the recommended value is 1 530 000 kWh per year. That means that energy consumption at the center should reduce by approximately 18 % to comply with the recommended value. The mall consists of 17 stores and the thesis examines five stores which are Toys Я Us, Rusta, Burger King, Babyproffsen and Webhallen. Measurements are taken on ventilation and lighting installations with the aim of studying the loads in the stores that consume the most energy. The goal is to come up with suggestions of actions to reduce energy consumption and costs.

    We concluded that lighting consumes the most energy in the warehouses; Toys Я Us, Rusta, Babyproffsen and Webhallen, while the largest load in the restaurants (Burger King) is the kitchen, which accounts for 75 % of the restaurants total consumption.

    In Rusta, we discovered that the electricity meter showed a lower value than the true consumption. After investigation, we concluded that the fault could be either in the electricity meter or in its current transformer and must be addressed.

    We have given a proposal to replace parts of the existing lighting installations, and given suggestion for sectioning certain parts in some stores. Further, we have given suggestions for reducing operating times on the ventilation units.

    Based on the above proposals and energy calculations, we concluded that these five stores has the potential to reduce the annual energy consumption from 1 865 270 kWh to 1 576 670 kWh, leading to a reduction by 15.5 %. This reduces costs by about 228 000 SEK per year

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  • 11.
    Abuibaid, Abdallah
    University West, Department of Engineering Science.
    Enhancement of an assembly linethrough robotization of the manual station2023Independent thesis Advanced level (degree of Master (One Year)), 20 HE creditsStudent thesis
    Abstract [en]

    This work is being carried out in collaboration with the TYRI Light industry to improve their existing assembly line, which currently has 8 stations. Out of these, three stations are operated by humans, and the rest are automated. The main focus of this project is on the first station, which is currently operated manually. While another master’s student from University West focuses on improving an automated second station and enhancing the fourth station, which is operated by a human worker. The seventh station, which operated manually, requires a human worker because of its complexity and flexibility of human.At this first station, there are two tasks involved. The first task is picking up components and placing them on an empty fixture, while the second task is picking up the finished product from the fixture and placing it on the palletizing process. Currently, it takes 19 seconds for a human worker to complete these tasks before sending the fixture to the next station.The goal of this project is to investigate whether this first station can be improved by using a robot instead. If a robot can perform these two tasks faster than 19 seconds, enhance workplace safety, and handle both tasks effectively without a need for more robots or external assistants. To achieve this, a discussion was made with the TYRI supervisor to select a collaborative robot for this task. To validate the work, ABB RobotStudio simulation software is used. The collaborative robot should be equipped with a specially designed gripper, which is suitable for the collaborative mode. Furthermore, in order to make the gripper suitable for TYRI’s components measurements, it was customized by a mechanism feature, which RobotStudio has.With the help of literature studies and various methods, the successful implementation of the robot was achieved. The robot was integrated outside the assembly line and was able to handle both tasks at the first station. Which indeed improved workplace safety. However, the robot took a total of 30.8 seconds to complete the tasks, which is longer than the 19 seconds goal was aimed for. As a result, the robot didn’t meet the desired cycle time required in this case

  • 12.
    Abusultan, Mukhlis
    University West, Department of Engineering Science.
    Robotize pizza making – Robizza: A conceptual model design and analysis for automating pizzerias2022Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Food Industry Automation is one of the sectors that took an advantage of industry fourth revolution, where food industry robots start to play a significant role in planting, transporting, processing, and even preparing various dishes. Pizza making is one of the food sectors that is entirely done by food experts and pizza chefs in small and medium business pizzerias, and even though pizza factories have mass production of pizza, they still don’t produce the required freshness and good taste pizza like the one you find it in pizza restaurants. The project studies food industry automation and then designs a conceptual model for robotizing pizza making process, providing a fully automated solution for medium and small pizza-making bakeries. Demonstrating what technologies are required to implement the idea and how to overcome challenges such as quality assurance and preserving hygiene standards adds to that, showing technical limitations and opportunities. The project study is based on theoretical and experimental aspects using an application development kit, Arduino IDE, and simulating the whole process with ABB robot studio simulation. 

  • 13.
    Aden, Mohamud Abdullahi
    et al.
    University West, Department of Engineering Science.
    Araya, Abel Russom
    University West, Department of Engineering Science.
    Hotet Ransomware mot företag, myndigheter och kommuner2022Independent thesis Basic level (university diploma), 5 credits / 7,5 HE creditsStudent thesis
    Abstract [en]

    Ransomware has increased in recent years, which has caused many companies devastating consequences. Incidents with ransomware can seriously affect business processes and leave companies without the data needed to run and deliver mission-critical services.

    This thesis is based on how to prioritize the threat of Ransomware in companies, authorities and municipalities. After years in the media about Ransomware attacks that have taken place against Swedish companies and authorities, this essay examines how well prepared and aware companies and authorities are about Ransomware attacks, everything from whether an attack has taken place, how they experience it and what solutions they have used to solve it.

    Based on the literature study and investigation we have conducted about Ransomware attacks and in combination with the interview study, conclusions can be drawn that with various organizations in both the private and the public sector, there are different views and experiences about an increased threat. But both the public and private sectors have plans, routines and strategies against Ransomware-attacks.

  • 14.
    Adhikari, Ayush
    University West, Department of Health Sciences.
    Enhancing Vulnerability Management in Large Organisations through Machine Learning - Based Prioritisation: A Case Study2023Independent thesis Advanced level (degree of Master (One Year)), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The number of vulnerabilities is increasing daily, and organisations are flooded by vulnerabilities in their IT environment. The increasing number of vulnerabilities in organisations' IT environments presents a significant challenge, requiring effective identification and prioritisation of critical vulnerabilities. Different techniques exist to this date, such as CVSS scoring or Risk-based scoring from solution providers to perform prioritisation of vulnerabilities. However, large industries with extensive assets often face difficulty in managing and fixing a large pool of vulnerabilities, as traditional techniques tend to classify numerous vulnerabilities as high or critical. This study proposes a machine learning model based on the K-means++clustering technique that leverages vulnerability data and asset financial value assessments to find patterns within vulnerability and group the most critical vulnerabilities. Our study successfully determined a group of the most critical vulnerabilities from a sample dataset of vulnerabilities from one of the large organisations. By considering the financial value of assets, our solution demonstrates a more accurate prioritisation, enabling organisations to allocate resources effectively and address the most critical vulnerabilities first. This study enhances vulnerability management practices in large organisations and serves as a foundation for further research and development in vulnerability prioritisation using machine learning techniques

  • 15.
    Adolfsson, Sebastian
    University West, Department of Engineering Science, Division of Production System.
    RatSLAM with Viso2: Implementation of alternative monocular odometer2017Independent thesis Advanced level (degree of Master (One Year)), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    In this work, a ROS (Robot Operating System) version of Open RatSLAM, [1] [2], was tested with Viso2 [3] as an alternative monocular odometer. A land based rover [4] was used to perform data acquisition and a remote control tool was developed to facilitate this procedure, implemented as ROS nodes on both Ubuntu 16.04 and on Android 7.0.An additional requirement that comes from using Viso2 is the need for camera information together with the image stream, which might require camera calibration. A ROS node to manually add this camera information was made as well as a node to change the generated odometry message from Viso2 to a form that RatSLAM uses. The implemented odometer uses feature tracking to estimate motion, which is fundamentally different to matching intensity profiles which the original method does and can hence be used when different properties of the visual odometry function is desired. From experiments, it was seen that the feature tracking method from Viso2 generated amore robust motion estimate in terms of real world scale and it was also able to better handle environments of varying illumination or that contains large continuous surfaces of the same colour. However, the feature tracking may give slight variations in the generated data upon successive runs due to the random selection of features to track. Since the structure of RatSLAM gives the system ability to make loop closures even with large differences in position, an alternative odometry does not necessarily give a significant improvement in performance of the system in environments that the original system operates well in. Even though both algorithms show difficulty with estimating fast rotations, especially when the camera view contains areas with few features, the performance improvement in Viso2 together with its ability to better maintain the real-world scale motivates its usefulness. The source code, as well as instructions for installation and usage is public

  • 16.
    Adolfsson, Sebastian
    University West, Department of Engineering Science, Division of Production System.
    RatSLAM with Viso2: Implementation of alternative monocular odometer2017Independent thesis Advanced level (degree of Master (One Year)), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    In this work, a ROS (Robot Operating System) version of OpenRatSLAM, [1] [2], was tested with Viso2 [3] as an alternative monocular odometer. A land based rover [4] was used to perform data acquisition and a remote control tool was developed to facilitate this procedure, implemented as ROS nodes on both Ubuntu 16.04 and on Android 7.0.  An additional requirement that comes from using Viso2 is the need for camera information together with the image stream, which might require camera calibration. A ROS node to manually add this camera information was made as well as a node to change the generated odometry message from Viso2 to a form that RatSLAM uses. The implemented odometer uses feature tracking to estimate motion, which is fundamentally different to matching intensity profiles which the original method does and can hence be used when different properties of the visual odometry function is desired. From experiments, it was seen that the feature tracking method from Viso2 generated a more robust motion estimate in terms of real world scale and it was also able to better handle environments of varying illumination or that contains large continuous surfaces of the same colour. However, the feature tracking may give slight variations in the generated data upon successive runs due to the random selection of features to track. Since the structure of RatSLAM gives the system ability to make loop closures even with large differences in position, an alternative odometry does not necessarily give a significant improvement in performance of the system in environments that the original system operates well in. Even though both algorithms show difficulty with estimating fast rotations, especially when the camera view contains areas with few features, the performance improvement in Viso2 together with its ability to better maintain the real-world scale motivates its usefulness.  The source code, as well as instructions for installation and usage is public.

  • 17.
    Agblad, Johannes
    et al.
    University West, Department of Engineering Science.
    Hultström, Mattias
    University West, Department of Engineering Science.
    Predikteringsmodell för berörings- och stegspänningar vid enfasig jordslutning i högspänningsnät2023Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Vid jordslutningar i högspänningsnät går stora strömmar ner i marken genom ledningsstolpars jordtag. Som en följd av detta skapas en förhöjd markpotential i denna punkt. Denna förhöjda potential sprider sig utåt från jordtaget i cirklar och avtar med avståndet från jordtaget. Detta gör att det uppstår spänningar mellan olika punkter i marken. I lokalnät som är direktjordade förs markpotentialen från matande station ut till alla punkter i nätet med hjälp av PEN-ledaren. Detta gör att en beröringsspänning kan uppstå mellan jordade föremål i nätet och marken rakt under.

    Arbetet med att utveckla en predikteringsmodell för beröringsspänningar har utförts för att kunna beräkna beröringsspänningen på ett enkelt sätt utan att ta ledningar ur bruk och koppla upp skrymmande mätutrustningar. Detta hade frigjort tid, förenklat arbetet vid mätningar av dessa spänningar och framför allt undvikt stora kostnader.

    Mätdata från NEKTAB används som en av hörnstenarna i modellen. Tillsammans med studier av teori inom området utvecklades modellen i ett beräkningsprogram. Modellen bygger på Carsons teorier för att beräkna impedanser i högspänningsnät.

    Denna rapport visar på svårigheterna med denna typ av prediktering. Resultaten från mätningar visar att beräknade värden kan avvika med upp till 2,5% av EPR. Detta kan vid verkliga jordslutningar innebära en avvikelse på 280 V.Slutsatsen av arbetet visar att det inte går att beräkna de beröringsspänningar som kan uppståpå det aktuella sättet. Orsaken till detta är att lokalnäten är jordade på fler ställen än i bara nätstationerna, många lokalnät har till exempel jordade kabelskåp. Detta gör att potentialförändringen i PEN-ledaren är svår att förutbestämma och därigenom blir beröringsspänningen också svårbestämd. 

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  • 18.
    Aguilar Gómez, Raquel
    University West, Department of Engineering Science, Division of Automation Systems.
    Investigation of a Flexible Manufacturing Scenario for Production Systems: Case study: GKN Aerospace Company2015Independent thesis Advanced level (degree of Master (Two Years)), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Nowadays the globalization of the market has a direct impact to the companies. On one hand, gives them the opportunity to spread their business but on the other hand increases the competition and the efforts to succeed. This project is pursuing to investigate and design a system capable to take upon and optimize the production within functional shops by in-troducing automation. Although the system it would be a standard solution for the functional shops, a case study for GKN Aerospace Company with its specifications has been carried out. The task become trickier due to the aeronautic sector requires a lot of work and effort to produce their products. The items and materials are expensive as well as the processes and treatments thus the introduction of automation is quite complex. This case study has accom-plished a research through the concepts and options to introduce automation within this production process. Taking under consideration the costs and efforts that would demand the investment for automation, the project propose a new and innovative manufacturing system "Move & Play", suitable with the features and requirements GKN Aerospace Company may need.The system proposed has been designed regarding to features such as movability, modularity and flexibility. These features have been considered essentials in order to make the system worth it and cost effective. The job-shop approach that the company use in its production contemplate the continuous change of products and introduction of new ones. Hence, the idea is to use the "Move & Play" system when it is required along the production. As a consequence, this system will create a "local product flow" along that point in the production that will organize the rest of the production or "global flow". Moreover it is expected to apply the concept of "plug-in" the processes that the system need at each time and therefore give flexibility to the system. With that purposes, the work has studied three different designs of the "Move & Play" system. Each design have considered different aspects and disposition. These designs have been compared according with criteria such as geometrical, the capacity and investment needed and the cycle time spent. Finally a conclusion on which design is the most suitable has been stated as well as a future work to continue with the work has been proposed.

  • 19.
    Ahmad, Slman
    University West, Department of Engineering Science.
    Flexible automated solutions for an assembly station in collaboration with  TYRI company2023Independent thesis Advanced level (degree of Master (Two Years)), 20 HE creditsStudent thesis
    Abstract [en]

    This project is being implemented in cooperation with TYRI Light Company, the company is serving many industrial sectors such as construction, mining, forestry, and transportation. The goal of this project is to provide a simulation of the automatic assembly station for as part of assembly line which assemble a product named 0909 compact lighting. Currently, with semi-automated production line, the average of production is 800 lights per a day (8 work hours), and three glue robots are utilized but componentsare manually assembled and fed. The emphasis will be on automating assembly and feeding as well as developing a mechanical design and a new glue dispenser. the validation and testing of all concepts will be in simulation environment. The fundamental idea behind this approach is flexibility, where just a little adjustment is needed whenever a new variable is added to the assembly line. After validating all the concepts, it turned out that the most suitable robot is articulated IBR 140T, and the mechanical tool with the distribution tool gave promising results, and the feeding system needs a lot of experiments, and it turned out that it is difficult to reduce the cycle time of a full assembly to one minute. But in order to benefit from the proposed solutions, the solution must be generalized to include the rest of the stations, allowing to reduce labour.

  • 20.
    Ahmed, Abdirahman
    et al.
    University West, Department of Engineering Science, Division of Mathematics, Computer and Surveying Engineering.
    Ibrahim, Ahmed
    University West, Department of Engineering Science, Division of Mathematics, Computer and Surveying Engineering.
    Säkerhetsanalys av CNAP-nätet i Högskolan Väst2021Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Since the birth of the internet, new advanced technologies have emerged that have affected how people live, work and interact with each other as well as the human view of the world. This has become the basis of the today’s information society. Today's information society is dependent on information and the threat to this information society has increased with the pace of digitalization. In order to prevent the attacks directed to the information society, information security has been developed, which is the core of how to protect society, both businesses and individuals. Businesses, authorities and other societal actors carry out security analyzes to find vulnerabilities that exist in their systems to prevent attacks at an early stage so that attackers are not given the opportunity to exploit the vulnerabilities that exist in the system.This thesis is about a security analysis carried out on a network called the CNAP network at a university. The purpose of this project is to identify network devices that the CNAP network consists, identify security threats directed to these networks, identify vulnerabilities using a vulnerability-scanning tool called Nessus and based on the identified vulnerabilities, make some suggestions on how these vulnerabilities can be counteracted. 194 network devices and 726 open ports have been identified using NetworkMapper (Nmap). Based on these network devices and open ports, various types of security threats have been identified such as open ports that should not be open and vulnerabilities such as Cisco Smart Install Remote Code Execution and Denial of Service Vulnerability. Improvements and countermeasures to these security threats and vulnerabilities have been suggested, such as upgrading the network devices to the latest version and disabling the open ports and services that are not used or pose a security threat to the system.

  • 21.
    Ahmetovic, Edvin
    University West, Department of Engineering Science.
    Estimation of Stator Temperature in an Electric Machinebased on Stator Resistance Computation2023Independent thesis Advanced level (degree of Master (One Year)), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Due to toughened CO2 emission standards the automotive industry is approaching a transition to zero-emission mobility. An accurate estimation of the stator temperature is an essential part of the motor controls and to protect the electric motor from overheating. An inaccurate estimation leads to bigger margins between estimated value and actual value to protect the electric motor which affects the performance. A literature study was performed which presented different methods that has been used in previous work to estimate parameters of an electric machine. The purpose of this master thesis is to find a suitable method and develop a temperature observer to estimate the stator winding temperature based on a resistance observer.In the development work three different methods were tested on a single-phase electric machine for the sake of simplicity. First method assuming steady state condition, second was the Forward Euler and third zero-order hold. The results showed that the zero-order hold method using a recursive least-square (RLS) optimization was performing the best in the higher frequencies but in the lower range the steady state RLS method was better which was also the method that was used on a three-phase electric motor model from a Nissan Leaf.The sensitivity analysis showed that the estimate of the stator resistance is sensitive to errors on the input variables and that the errors are highest in the mid-torque range and in the lower part of the speed range. The error on the input variables was arbitrarily chosen of +3 % and was added separately on the inductances and voltages of the d- and q-axis 𝐿𝑑, 𝐿𝑞, 𝑣𝑑, 𝑣𝑞, the rotor speed 𝜔 and the flux-linkage 𝜑. The variable that was affecting the resistance estimation the most was when a fault of 3% was introduced on the rotor speed 𝜔 which gave an error of more than -1200% on the estimated resistance. In nominal conditions, i.e. room temperature and constant stator temperature, the results showed an accurate resistance estimation of -0.4 – 1.4 % followed by an accurate temperature estimation

  • 22.
    Ahrnfeldt, Olof
    University West, Department of Engineering Science, Division of Industrial Engineering and Management, Electrical- and Mechanical Engineering.
    Användning av reservelverk för att minska avbrottstiden på grund av fel på mellanspänningskablar2019Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Every Network operator strives to have as few and short outages as possible. Network operators therefore work continuously to convert the overhead lines to cables. Therefore, there is a need to gather knowledge about outages on cables and look into methods to decrease the outage time. There are laws and guidelines that need to be taken in consideration that limit the allowed maximum outage time and that is why backup generators could be a method to prevent breaking them.

    Problems that can arise regarding cable outages are to locate the flaw. Visual troubleshooting is often not a viable option which requires that the prerequisites are good enough to be able to use other fault detection methods. Factors that could affect the possibilities to use other measurement methods are the length, number of joints and the surrounding environment of the cable.

    Backup generators are most commonly used for maintenance and to reduce the outage time. The generators are mainly connected at the low voltage busbars but with additional equipment as portable transformers it can also be connected to the high voltage busbars.

    The result of the work performed shows that there are different factors that affect the outage time and frequency. One contributing factor that leads to increased outage time is the length of the cable. It may be due to difficulties to locate the flaw or that the cable pass inaccessibility areas increases when the length of the cable increases. During the winter period the average outage time is longer as compared with summertime, but during the summertime the outage frequency is higher.

    Vattenfall have backup generators, portable transformers and diesel containers available for booking on the internal website. The most common time before a backup generator is connected is between three and four hours. By using backup generators, it would be possible to reduce the outage time on about 100 outages during the analyzed time period. The potential decrease of SAIDI by using backup generators has not been able to be calculated because of lack of data.

    Available data is based on what is documented and there have probably been more situations when backup generators have been used but not been documented. With access to higher quality documentation the analyzes could be done more accurate.

  • 23.
    Akiki, Cesar
    et al.
    University West, Department of Engineering Science, Division of Computer, Electrical and Surveying Engineering.
    Torstensson, Daniel
    University West, Department of Engineering Science, Division of Computer, Electrical and Surveying Engineering.
    Hur routingtabellens storlek påverkar paketets fördröjning i en router eller L3 switch2017Independent thesis Basic level (university diploma), 5 credits / 7,5 HE creditsStudent thesis
    Abstract [en]

    The internet is growing, and more devices are becoming connected for each day that passes by. This will increase the number of routes in the routing-table on the routers and L3 switches and as they are increasing it will affect the delay on the packets traversing between the source and destination. Or does it matter? Does the size of a routing table affect the delay? In this study, we have researched if there is a difference in the delay on the packets in a comparison to the size of the routing-table and this is compared between a router and L3 switch. During this study, we have been using a desktop computer that has two network interfaces installed in it and is connected to a router or L3 switch. We used three different programs on the computer that have been very helpful for completion of our work: Wireshark, to monitor and capture packets and the time between the two network interfaces on the desktop computer. Tftpd32, to copy the running-configurations from the router or L3 switch over to the desktop computer and back. Ostinato, is used to generate and send out packets on the network. All the results we got from our tests point to that there is no increase in delay no matter how much the routing-table is increasing. These results challenge previous studies that tells us the opposite, that the increase of a routing-table does have an increase in delay.

  • 24.
    Akinboyewa, Christopher
    et al.
    University West, Department of Engineering Science.
    Udrescu, Elena Simona
    University West, Department of Engineering Science.
    Wireless Charging Technology Infrastructure for Ferries in Göteborg (Västra Götaland)2023Independent thesis Advanced level (degree of Master (One Year)), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The maritime transport sector makes a significant contribution to greenhouse gas (GHG) emissions, playing a consistent and increasing part in global CO2 emissions. Electrification of marine transportation is a key and necessary step for achieving the goals of the Paris Agreement and for avoiding the worst consequences of climate change. Sweden is among the first countries pleading for zero-emission transportation within 2045. However, one of the key challenges facing the widespread adoption of electric boats is the availability and efficiency of charging infrastructure. 

    Wireless power transfer technology with more focus on inductive power transfer technology in the marine sector was investigated. The focus is wireless charging infrastructure for passenger ferries in Goteborg. Vesta was the ferry chosen for the case study and it operates on the Saltholmen to Vrångö route. The route, schedule, and ferry energy consumption were investigated to implement the wireless charging infrastructure. Swot analysis was performed to show the strengths, weaknesses, opportunities, and threats of the research. Based on this investigation, the power profile, energy storage, and adopted solution with its system were proposed.

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  • 25.
    Akram, Yasser
    et al.
    University West, Department of Engineering Science, Division of Industrial Engineering and Management, Electrical- and Mechanical Engineering.
    Mirzad, Elias
    University West, Department of Engineering Science, Division of Industrial Engineering and Management, Electrical- and Mechanical Engineering.
    Studie av övertoners inverkan på relätripptiden hos ett elektromekaniskt överströmsrelä2019Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    A problem that has been noticed in the electricity grid is the increase in level of harmonics. In some cases, there may also be currents or voltages with frequencies that differ from the fundamental tone and this leads to the grid having harmonics meaning that when loads and components in the electricity grid are not sinusoidal, harmonics occur. For example, an increase in these types of loads e.g. charging an electric car or computers, in the electricity grid gives rise to an increasing harmonic content.

    In view of the aforementioned, this thesis has been carried out in collaboration with the Megger Sweden AB, Stockholm, as the official client for this study. The purpose here is to study the effect of harmonics on the relay trip time of an electromechanical overcurrent relay that is installed in the power grid's control facilities.

    The tests are performed with the test instrument Sverker 900 and an electromechanical overcurrent relay, ASEA RI. For testing the RI relay, a Swedish standard, an upcoming international standard as well as instructions from the client have been thoroughly followed and applied. The results of the tests shows the difference between the trip time with harmonics and the trip time for the fundamental tone.

    Conclusions based on the results are partly that the overcurrent relay is slower at weak currents, that is 2.8A and 3A respectively, as well as for long trip times in relation to the behavior without harmonics. According to the findings conducted herein, there is no significant correlation between the presence of harmonics and the influence of the relay trip time on medium and strong currents, between 4A-8A, or on shorter trip times.

    By reason of the time constraint experienced in conducting this study, the results and findings reached leaves a sound potential and promise for future tests conducted at different harmonic levels. A future recommendation for similar studies will be to test only at low currents, long trip times and slow disk speeds as this would facilitate the possibility of fulfilling a more robust result analysis.

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  • 26.
    Al Hayani, Musab
    University West, Department of Engineering Science, Division of Automation and Computer Engineering.
    Offline Programming of Robots in Car Seat Production2013Independent thesis Advanced level (degree of Master (One Year)), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Company Purtech in Dals-Ed manufactures molded polyurethane (PUR). Examples of products that include polyurethane are car seats. Robots are used to fill the molds with PUR and to apply the release agent (wax) in the empty molds.

    Turning from online programming into a graphical offline programming of release agent spraying robots is going to simplify the process by:

    1. Applying less of release agent to avoid polluting environment, to produce an easier removal of moulds, for the sake of homogeneous moulds and for economical saving in the cost of release agent
    2. Adaption of spraying paths to variation in production speed.
    3. Programming of complex spraying trajectories to deal with sharp geometrical subsurface
    4. Decreasing onsite programming time (when program a new workpiece or modify an old one); so that robots would be free for production.

    While turning into offline programming brought the challenges of:

    1. Impact of variation in the production speed
    2. Lack of 3D models of workcell’s equipments
    3. Robot joint configuration when paths and robtargets are in move.
    4. Physical Joint limits, Singularities & Reach limits
    5. Collisions within the cell space.

    At the end, the following objectives are successfully met:

    1. Adaption of spraying programs to variation in production speed by developing and embedding a method in those programs.
    2. Graphical offline generation of spraying trajectories and optimization of those trajectories to the Purtech condition of spraying allowed time for each carrier.
    3. Simulation of release agent spraying process; and producing of a well structured RAPID program that reflect the simulated process.

              

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    Offline Programming of Robots in Car Seat Production
  • 27.
    Albadri, Rand
    University West, Department of Engineering Science, Division of Computer, Electrical and Surveying Engineering.
    Jämförande analys av driftsäkerhet medRTU och PLC2015Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This thesis will make a comparative analysis of the operation safety of the wire connection to Remote Terminal Unit (RTU) and Programmable Logic Controller (PLC) with bus-controller. The report describes the basic description of the difference between these two systems and will explore which is safer and more economic with consideration to qualification according to Swedish energy companies' guidelines for dam safety (Ridas).Through course literature, ABB Bok, internet web sits and interviews with Skellefteå Kraft AB staff the result of this report have been created.The report results prove that PLC with bus-controller will operate operationally safe and profitable compared to wire connection to RTU. Results also showed that there is nothing which prevents to install bus-controller according to RIDAS but certain features should be installed.

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  • 28.
    Albayat, Mohammed
    University West, Department of Engineering Science, Division of Industrial Engineering and Management, Electrical- and Mechanical Engineering.
    Förebyggande Underhåll för en batteriåtervinnningsfabrik2022Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Rapporten som redovisas här är ett examensarbete med uppdrag att genomföra förebyggande underhåll i kross- och separationsavdelningen på en batteriåtervinning fabrik. Fabriken återvinner litiumjonbatterier som används i elbilar. I kross- och separationsavdelningen är det mycket buller och damm som en följd av skakande och krossande processerna i den mekaniska separationen. Det är tunga maskiner som genom olika operationer sliter isär metallkomponenterna i batteriet till mindre delar för att slutligen mala dem och separera beståndsdelarna i materialet åt med avseende på deras magnetiska egenskaper. Förutsättningar i kross och separationsavdelningen medför ohälsosam miljö för människor, vilket leder till att avdelningen måste styras automatiskt utan att medarbetare behöver befinna sig i avdelningen. Det föreslagna förebyggande underhållssystemet som behandlas i rapporten stöds av teknik från Industri 4.0. Industri 4.0 är benämningen på en rad moderna teknologier och koncept som används inom automation. Maskin-till-Maskin kommunikation och Internet of things(IoT) är integrerade för högre grad av automation. Förebyggande underhållsarbetet som presenteras baseras på en förstudie analys som nischar sig inom förebyggande underhåll och industri 4.0. Förebyggande Underhållsarbetet som redovisas i denna rapport kommer inkludera ett signalflödesschema som ska visualisera kommunikationen mellan enheterna i avdelningen,en schematisk design för övervakningssystem, ventilationen och ett underhållsschema för maskinerna i avdelningen

  • 29.
    Alchami, Wael
    University West, Department of Engineering Science.
    Beräkning av dimensionerande felströmmar med hänsyn till utlösningsvillkoret i ett direktjordat lågspänningsnät2022Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    A safe and reliable fault disconnection is an important function and preventive measure that needs to be ensured to avoid any damage that could damage equipment and injure person. Fault current value is a decisive factor that must be considered for safe fault disconnection. The report analyzes and presents proposals for a calculation method of dimensioning fault currents with respect to the tripping condition in a solidly earthed low-voltage network. The fault currents that the report deals with are single phase earth faults that are dimensioned when using fuses and two-phase short circuits that are dimensioned when using circuit breakers. By conducting a literature study and interviewing experienced engineers and project managers, various formulas and input data that are needed in the calculation have been taken out. Smart Power is an application that ABB uses to, among other things, perform various real-time calculations of short-circuit impedances, currents and voltage drops. The work's goal is to produce materials such as input data and formulas for Smart Power to be able to make calculations for single phase earth faults and two-phase short circuits in a directly earthed low-voltage network. A proposal for windows that can be implemented in Smart Power is presented in the report. How close the exact value is to the result is greatly affected by the accuracy of the input data to Smart Power.

    The report shows how an approximate residual current value can be calculated with a limited need for input data so that it becomes manageable for a typical Swedish industry. A single-pole earth fault affects two phases in the feeding network, while a two-phase short circuit affects all phases in the overlying network.

  • 30.
    Alhammadeh, Kinda
    University West, Department of Engineering Science.
    Automatic Generation of Hazardous Zones in a Collaborative Plug&Produce System2022Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    A collaborative Plug&Produce system is a flexible, modular, and reconfigurable system that helps cope with fluctuating market demands. The idea is to be able to reconfigure the production line in minutes instead of hours or days. This reconfiguration is made by adding or removing a module to achieve different manufacturing goals. Guaranteeing the safety of this system is a crucial question in achieving the desired flexibility, as any change in the system requires a new risk assessment. The risk assessment process is still conducted manually, and it is a time-consuming process. This thesis work is a part of several studies carried out at University West to create an automated method to conduct the risk assessment in a way compatible with the collaborative Plug&Produce system. In University West studies, the Plug&Produce system is controlled by a Configurable Multi-Agent System (C-MAS). Particularly, in this thesis work, a concept is developed to automatically generate the hazardous zones of the collaborative Plug&Produce system to facilitate the process of hazards identification during the risk assessment process after every reconfiguration. The needed data to generate the hazardous zones are related to two systems. The first system is the collaborative robot system, where “Speed and separation monitoring” is the collaborative method used in this work. A protective separation distance (PSD) will be maintained between the robot and the operator to avoid collisions. The second system is the Plug&Produce system controlled by C-MAS, where the system consists of parts and resources. The parts have goals to be implemented, and the resources have the skills to implement the parts' goals. The resources have different variables that help describe the resources and ensure the compatibility between the resources to perform a particular sequence of skills called a process plan. These resource variables are saved in a database and help generate the hazardous zones. Additional data related to the Plug&Produce system controlled by C-MAS is also needed to generate the zones, such as the table of the identified hazards and data about the hazardous zones of the adjacent modules.

    The hazardous zones are represented in this work as bounding volumes describe the volumetric occupancy of the robot’s moving link. The cuboids are chosen as bounding volumes to represent the hazardous zones.The developed concept is tested on a cell to produce a wooden walls simulation created in Robot Studio. Two process plans that perform the same goals are used in this test, and the results have been compared and discussed to validate the proposed concept.

  • 31.
    Ali, Ali Ahmed
    University West, Department of Engineering Science.
    Förstudie inför utbyte av reläskydd för synkrongenerator2023Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The degree work is carried out in autumn 2022 at Hitachi Energy in Ludvika. The report is about evaluating existing protections and giving suggestions on which protection functions are possible to use for a synchronous generator in a high-power lab. The current protections are considered old and there is a desire to improve the protection functions to ensure a high level of operational safety and protection for both people and equipment.

    The work includes the basic principles of protection philosophy and relay protection theory. In this work, the calculation methods that can be used to finalize the new settings for relay protection are presented. There are many different relay protections, each with its specific characteristics and area of use. The most common types are overcurrent protection, differential protection and earth fault protection. In this report, an investigation has been carried out to evaluate electromechanical protections and identify possible improvements to these protections to increase operational reliability and reduce the risk of operational interruptions. Through examination of test reports and data sheets, it has been established that the existing electromechanical guards are functional, but age-related problems may arise due to the moving and service-requiring parts of these guards.

    A possible solution that has been identified is to replace the existing electromechanical protections with the REG 670, a digital relay protection with high performance and reliability. The REG 670 has a range of protection functions that can be adapted to the specific requirements for the protection of electrical machines and systems. Achieving an accurate and reliable level of protection for the short-circuit generator requires custom relay protection settings to handle high short-circuit currents without triggering unintended tripping events. Earth protection is also an important factor to consider as high earth fault currents can occur due to the high short circuit capacity.

    To ensure that the protections work properly, higher time settings are suggested for the existing overcurrent protections. Finally, as future work, it is recommended to further investigate the selectivity of the whole plant as well as collect important documents to ensure a correct and reliable level of protection for the generator.

  • 32.
    Alléus, Jonas
    et al.
    University West, Department of Engineering Science, Division of Industrial Engineering and Management, Electrical- and Mechanical Engineering.
    Dalin, Patrik
    University West, Department of Engineering Science, Division of Industrial Engineering and Management, Electrical- and Mechanical Engineering.
    Vass, Sebastian
    University West, Department of Engineering Science, Division of Industrial Engineering and Management, Electrical- and Mechanical Engineering.
    Planering av laddstationer vid flerbostadshus2018Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Sales of electric vehicles grow annually which increases the need for charging stations on parking lots at apartment houses. This report explore both the technical and the economical aspects of electric car charging for Stenungsundshem. The types of electric cars available on the market that can be charged by energy from the electric power network is the Plug-in hybrid and the electric car. The most common type on the market is the Plug-in hybrid which is driven by an electric motor and an internal combustion engine. The electric car is only driven by an electric motor. Charging times for electric cars depend on if the charging station is designed with normal charging or fast charging. For home charging, normal charging is the most common type of charging where the car is fully charged after six to ten hours. The connection between charging stations and cars can be made by different types of connectors. The European standard is the Type 2 connector. Safety is very important when charging electric cars, Therefore, charging stations have been divided into four different safety modes. Safety modes differ depending on the type of communication available between the charging station and the car. Mode 3 is the standardized mode in the Nordic countries. Charging of electric cars can result in power peaks which the main fuse must be dimensioned for. Power peaks can be reduced by using some type of load balancing system where available power during the day is distributed between charging stations to keep the power consumption below rated power. Terms of how charging is done and installation of charging station must be in compliance with Ellagen. For easier compliance and clarification of Ellagen standards and regulations should be used. In this project cable dimensioning by power requirements for different amounts of charging stations has been made, PEX insulated aluminum cable is exclusively used within the project. The market of charging stations is explored to look at different solutions and costs for charging stations and routing of cables. The best option for Stenungsundshem is currently to install two charging station for charging outlets to four parking spaces. Contributions like “Klimatklivet” can reduce total costs of investments for charging stations and cable routing with up to 50%.

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  • 33.
    Almardoud, Nour
    University West, Department of Engineering Science, Division of Production Systems.
    Identifying the Potentials for Moving from Manual to Automated Systems2019Independent thesis Advanced level (degree of Master (One Year)), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Parker Hannifin Manufacturing Sweden AB is an international company with manufactory sites all around the world. The site in Trollhättan is part of the Pump & Motor Division Europe. The Factory has worked a lot with automating the manufacturing section. Many robots are implemented in the factory to produce the simple parts which need to be assembled to interduce the last product. Parker are now interested in starting the process of automating the assembly stations for the 3 products they produce in this site. The three products are Truck pumps, fixed and variable displacement pumps (LBP), variable hydraulic motors (VM) and fixed hydraulic motors (FM). Each one of the three types has different sizes and different series.

    This work focuses on analysing the current system which consists of seven assembly station, 101, 102, 201, 202, 203, 301 and 302. After analysing the current system, a work on finding the potentials for moving from manual to semi-or automated stations for each station is presented. Seven potentials were found. The first potential which handle a bout a central pressing robot cell is a common potential for all the stations, and the other potentials are for each station separately. Testing and validation for all the potentials where the automation can be implemented and started with, the cycle time for the operations and the productivity, the workspace and material handling in addition to the level of the ergonomics for these stations.

    The complexity of these solutions, the advantages and disadvantages and a safety analyses are also presented. And how to optimize the current system for reaching a high level of automation is discussed.

  • 34.
    Al-Masri, Nisreen
    University West, Department of Engineering Science, Division of Production Systems.
    Ethical margins for Internet of Robotic Things (IoRT): An Exploratory Study: IoRT Ethics from a healthcare perspective2021Independent thesis Advanced level (degree of Master (Two Years)), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The Internet of Things (IoT) concept is getting attention recently, and the number of connected devices is rising rapidly, climbing above one billion. Combining both IoT and Robotics ends up with the Internet of Robotic Things (IoRT). This paper aims to explore the ethical standards of IoT and Robotics to build up the ethical margins and structures of IoRT in the healthcare sector. Thus, an ethical pyramid consists of security, privacy, and safety in such systems; this pyramid helps to understand the current ethical principles and how to adjust and translate them into protocols suite IoRT in the medical sector. These protocols are formulated in the form of responsibilities and rights of IoRT subdivision which is Internet of Medical Robotic Things (IoMRT

  • 35.
    Almström, Love
    et al.
    University West, Department of Engineering Science.
    Carlsson, Henry
    University West, Department of Engineering Science.
    Proposing a new mobile solution for 2FA in Linux based on One-Time Passwords and QR-codes2023Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Denna uppsats föreslår en ny lösning för ett tvåfaktors-autentisering system (2FA) som används vid Secure Shell (SSH) inloggning till en Linux server och jämför denna nya lösning med industristandarden, med fokus på enkelhet och användarvänlighet av systemen. Eftersom användningen av digitala tjänster och system ökar, och användare använder säkrare system för att spara sin data på, måste nya sätt att skydda sig utvecklas. Idag kan hackare få tillgång till eller bryta sig igenom den traditionella enfaktors-autentiseringen av användarnamn och lösenord enklare än någonsin tidigare vilket är anledningen till att 2FA uppfanns, där en ytterligare faktor, eller enhet, används efter inloggningsförsöket för att bekräfta att det är den rätta användaren försöker få åtkomst. Flera lösningar för detta existerar redan, den mest använda sådana är Google Authenticator, förkortat till GA. Google Authenticator funkar bra, men kan behöva flera förbättringar. Denna avhandling syftar till att föreslå och utveckla ett nytt 2FA-system som är enkelt och lätt att använda, och fixar mycket av den negativa feedback som Google Authenticator fått online. Denna avhandling ger också en analys av detta föreslagna system som har byggts, och Google Authenticator, och jämför dessa. Krav har samlats in, mål har fastställts och ett prototypsystem/applikation har byggts. I slutändan visar det utvecklade prototyp systemet jämfört med Google Authenticator en ökning av både enkelhet och användarvänlighet, och uppmärksammar vad som kan ändras och implementeras för att göra nuvarande 2FA-system bättre överlag.

  • 36.
    AlNabulsi, Yasan
    University West, Department of Engineering Science, Division of Production System.
    Robot motion control based on 3D mouse tracking2017Independent thesis Advanced level (degree of Master (One Year)), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The manufacturing industry and associated systems are being developed in an increasing manner to cover the market needs, where the manufacturing companies are continuously racing and competing to achieve high productivity rate and better production quality. In this thesis work, an advanced method for motion control of industrial robots has been investigated and implemented. This method is based on motion tracking of a 3DSpaceMouse, which was used to perform movements by the operator. The benefits and disadvantages of this method were discussed in this thesis work. It mainly showed a high accuracy in response to the motion applied by the 3DSpaceMouse, and a great stability regarding the programming environment that was used to build it. The movements applied by the 3DSpaceMouse were successfully captured and stored in variables in the programming platform. The capturing and storing process was successfully created as a package and prepared to be exported for usage by other software. Complete simulation was performed for an industrial robot, and successful communications among the various hardware and software components of this solution were accomplished. This has formed a complete integrated solution that has also included a user-friendly HRI. This HRI made it easy and simple to track the motion control processes and establish connections with the robot controller. Thus, it can be considered a feasible solution for motion control of industrial robots, which can be used by the manufacturing companies. Several tests and verification processes were carried out to obtain accepted results and to succeed in implementing a working model. Some errors and unexpected events have appeared during the work, which required handling in order to achieve a working integrated system.

  • 37.
    Alshalabi, Ward
    University West, Department of Engineering Science.
    A model-driven approach for programming multi-agent systems: A tool suite for modeling and generating ROS-based software for the agent2022Independent thesis Advanced level (degree of Master (One Year)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Multi-agent systems (MAS) have gained a lot of attention among researchers during the last decade, they have also been widely used within a variety of industrial fields including robotics, automation, and automotive industries. A multi-agent architecture could be used for designing systems that perform complex tasks which cannot be handled in a monolithic way, such architecture ensures that different participating agents (hardware or software) are fully decoupled from each other which makes it easier to design, program, and deploy them separately, this also makes the complete system fully dynamic and capable of handling later structural changes like adding, removing or changing the behavior of any of the participating agents. As the agents are not aware of each other’s existence in the system, The gained advantages when using such a multi-agent architecture come with difficulties related to the interactions between the system agents, the agents need to register themselves in the system, share information about their skills, abilities and provided services with all other agents inthe system, only this way their services could be made use of by the other agents. These difficulties make configuring, programming, maintaining, and modifying multi-agent systems a hard and time-consuming task to be accomplished even when using advanced development frameworks which natively support the ability to configure multi-agent systems such as JAVA Agent DEvelopment Framework (JADE) and Robot Operating System (ROS).

    In this master thesis, a MAS text-based modeling language is proposed. Moreover, a complete tool suite for modeling, and automatically programming ROS-based multi-agent systems is presented. The defined MAS modeling language and its corresponding tool suite aim to make the process of designing, programming, compiling, and installing the software of multi-agent systems easier and more budget and time efficient for companies and researchers. A standard and relatively complex example of a multi-agent system from the automotive industry was presented and modeled using the proposed MAS modeling language. Later, the implemented tool suite was used to generate code out of the model, compile it, install it and run it in a Linux environment, the generated code was analyzed using a static code analyzing tool and different code metric values were registered. The executed final binary format of the generated software was also analyzed during run-time using ROS graphical system monitoring tools. Future system maintenance and adaptations were simulated by manually modifying the initially created automotive system model and introducing system updates to it, the software was regenerated, and the static code and software run-time analysis were reperformed, results from both analysis reports were compared to the corresponding analysis reports which were created using the previous version of the system model. The results have shown that the proposed modeling language can be used for modeling large and complex multi-agent systems from a real-world example. The implemented toolsuite works as expected, it generates ROS-based software for multi-agent systems which is compilable, installable, and executable. During run-time, the software also behaves according to how the system was modeled. Finally, the registered statistical and code metrics measurements have proven that using such a modeling approach for automatically programming multi-agent systems reduces the development and maintenance efforts of these systems significantly

  • 38.
    Amana, Ahmed
    University West, Department of Engineering Science.
    Robustness in design of experiments in manufacturing course2022Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [zu]

    Design of experiment (DOE) is a statistical method for testing effects of input factors into a process based on its responses or outputs. Since the influence of these factors and their interactions are studied from the process outputs, then quality of these outputs or the measurements play a significant role in a correct statistical conclusion about the significance of factors and their interactions. Linear regression is a method, which can be applied for the DOE purpose, the parameters of such a regression model are estimated by the ordinary least-squares (OLS) method. This method is sensitive to the presence of any blunder in measurements, meaning that blunders significantly affect the result of a regression using OLS method. This research aims to perform a robustness analysis for some full factorial DOEs by different robust estimators as well as the Taguchi methodology. A full factorial DOE with three factors at three levels, two replicants, and three replicants are performed is studied. Taguchi's approach is conducted by computing the signal-to-noise ratio (S/N) from three replicants, where the lower noise factor means the stronger signal. Robust estimators of Andrews, Cauchy, Fair, Huber, Logistic, Talwar, and Welsch are applied to the DOE in different setups and adding different types and percentages of blunders or gross errors to the data to assess the success rate of each. Number and size of the blunders in the measurements are two important factors influencing the success rate of a robust estimator. For evaluation, our measurements are infected by blunders up to different percentages of data. Our study showed the Talwar robust estimator is the best amongst the rest of estimators and resists well against up to 80% of presence of blunders. Consequently, the use of this estimator instated of the OLS is recommended for DOE purposes. The comparison between Taguchi’s method and robust estimators showed that blunders affect the signal-to-noise ratio as the signal is significantly changed by them, whilst robust estimators suppress the blunders well and the same conclusion as that with the OLS with no blunder can be drawn from them.

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  • 39.
    Amouzgar, Kaveh
    et al.
    University of Skovde, Jonkoping University.
    Strömberg, Niclas
    University West, Department of Engineering Science, Division of Welding Technology. Jonkoping University, Orebro Univ, University University West - Sweden.
    An approach towards generating surrogate models by using RBFN with a priori bias2014In: PROCEEDINGS OF THE ASME INTERNATIONAL DESIGN ENGINEERING TECHNICAL CONFERENCES AND COMPUTERS AND INFORMATION IN ENGINEERING CONFERENCE, 2014, VOL 2B, AMER SOC MECHANICAL ENGINEERS , 2014, Vol. 2BConference paper (Refereed)
    Abstract [en]

    In this paper, an approach to generate surrogate models constructed by radial basis function networks (RBFN) with a priori bias is presented. RBFN as a weighted combination of radial basis functions only, might become singular and no interpolation is found. The standard approach to avoid this is to add a polynomial bias, where the bias is defined by imposing orthogonality conditions between the weights of the radial basis functions and the polynomial basis functions. Here, in the proposed a priori approach, the regression coefficients of the polynomial bias are simply calculated by using the normal equation without any need of the extra orthogonality prerequisite. In addition to the simplicity of this approach, the method has also proven to predict the actual functions more accurately compared to the RBFN with a posteriori bias. Several test functions, including Rosenbrock, Branin-Hoo, Goldstein-Price functions and two mathematical functions (one large scale), are used to evaluate the performance of the proposed method by conducting a comparison study and error analysis between the RBFN with a priori and a posteriori known biases. Furthermore, the aforementioned approaches are applied to an engineering design problem, that is modeling of the material properties of a three phase spherical graphite iron (SGI). The corresponding surrogate models are presented and compared.

  • 40.
    Amponsah, Nana Frimpong
    University West, Department of Engineering Science.
    Securing connected vehicles with the MITRE ATT&CK Framework: A risk based approach2023Independent thesis Advanced level (degree of Master (One Year)), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    In the rapidly evolving landscape of connected vehicles, the threat of cyberattacks has emerged as a significant concern. This research embarked on a journey to develop a riskbased strategy to protect these vehicles, leveraging the MITRE ATT&CK framework. An exhaustive literature review laid the foundation, revealing gaps in current defense mechanisms and highlighting the urgency of addressing vulnerabilities in connected vehicles.Using the MITRE ATT&CK framework, specific vulnerabilities in connected vehicles were identified. A bespoke risk assessment model was then crafted, which prioritized these vulnerabilities based on their potential impact and exploitability. This prioritization was not just data-driven but was further refined with insights from industry experts.To address the identified vulnerabilities, countermeasures were developed, rooted in the principles of the Layered Security Model. These countermeasures underwent rigorous testing in simulated environments, ensuring their robustness against potential cyber threats. Continuous monitoring mechanisms were also established to ensure the long-term efficacy of these countermeasures.The culmination of this research offers a comprehensive strategy to safeguard connected vehicles against cyber threats. The findings not only contribute significantly to the existing body of knowledge but also provide actionable insights for industry practitioners. The journey, from identifying vulnerabilities to developing and testing countermeasures, underscores the importance of a holistic, risk-based approach in the realm of connected vehicle cybersecurity

  • 41.
    Andell, William
    et al.
    University West, Department of Engineering Science.
    Eskel, Filip
    University West, Department of Engineering Science.
    DDoS Defense: Next-Generation Firewall versus Traditional Firewall2023Independent thesis Basic level (university diploma), 5 credits / 7,5 HE creditsStudent thesis
    Abstract [sv]

    Syftet med detta examensarbete var att utvärdera hur två olika brandväggar, en nästa generationens brandvägg och en traditionell brandvägg, hanterade en mindre distribuerad denial of service-attack. Enheterna kördes så nära dess förkonfiguration som möjligt. Testningengenomfördes i en kontrollerad labbmiljö på Högskolan Väst.

    Ett botnät bestående av 17 datorer användes och styrdes via en kommandocentral som använde IRC för att utföra attackerna. Enheterna testades med TCP- och UDP-baserade attacker under en tid av fyra minuter vardera. En dator var ansluten till det interna gränssnittet där vi kontrollerade minnet, CPU och latensen. En annan dator från botnätgränssnittet kontrollerade latensen från botnät.

    Resultaten visar att nästa generationens brandvägg (FortiGate40F) presterar bättre än den traditionell brandväggen (ASA 5506-X). Både Cisco ASA 5506-X och FortiGate 40F kör med 4 CPU-kärnor, där ASA 5506-X har 1250 MHz per kärna medan FortiGate 40F bara har 1200M MHz per kärna. ASA 5506-X har också 113,24% mer RAM än FortiGate. Trots att ASA 5506-X har fördelen när det gäller hårdvara, presterande FortiGate 40F bättre vid varje attack. Detta beror med stor sannolikhet på skillnaden i mjukvara hos de olika brandväggar

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  • 42.
    Andersson, Andreas
    University West, Department of Engineering Science, Division of Automation Systems.
    Utredning av variablerna som påverkar storleken på brytspänningen i lindningskopplare2015Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The recovery voltage is the voltage that occur when the transition resistor in the tap-changer leaves its previous position during an operation cycle. The amplitude of the recovery voltage depends on the leakage inductance.

    If the leakage inductance is unknown, the recovery voltage can instead be calculated using a FEM-program called ACE (internal ABB-program) in conjunction with Mathcad. First, the reactances between the windings are calculated in per unit (p.u) using ACE and they depend on the winding layout. It is time consuming to use ACE and Mathcad and the task has been to investigate the parameters that affects the recovery voltage and to develop a simplified calculation of it.

    Through simulation using ACE of a number of different winding layouts one soon comes to the conclusion that there are simply too many parameters affecting the reactances. Although the simplified calculations that despite this has been developed, they soon prove to be too rough to be useful. Mathcad is even more complex with heavy calculations that are not easy to grasp.

    However, this thesis has given more knowledge about the way the reactances are affected by the geometry of the windings, even though it was not possible to in a reasonable way simplify the calculation of ACE and Mathcad.

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  • 43.
    Andersson, Andreas
    et al.
    University West, Department of Engineering Science, Division of Computer, Electrical and Surveying Engineering.
    Hägerström, Martin
    University West, Department of Engineering Science, Division of Computer, Electrical and Surveying Engineering.
    Beredningsarbete på Galtö med undersökning av miljöaspekter vid ombyggnad av distributionsnät2016Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This thesis deals with the practices of processing work. The work is being performed with TROLK El & Tele AB and is ordered by Ellevio AB. The area that the work is carried out at is Galtö in Tanum. The area includes about 10 km cable installation, 4 substations and 5 satellite substations and three low voltage areas where the grid are going to be rebuilt. Ellevio AB has invested in this project as they want to weather proof and ensure a high quality of the power delivery. The preparatory work that is presented as a proposal TROLK can continue to work with and apply for the relevant permits. These permits have been accounted for when this work has been prepared. The existing overhead line will be dismantled when the new grid has been connected. The overhead line is approximately 5.2 km long and includes nine pole mounted transformers. The work is based on the project documents that Ellevio has provided, though some changes have been made where necessary.

    The thesis also identifies the environmental aspects arising from the dismantling of an overhead power grid and investigates alternative solutions to reduce the environmental impact. When TROLK are working with projects commissioned by Ellevio they are using the environmental plan handed by Ellevio. The environmental plan have been studied and compared with other actors' environmental plans in order to identify potential improvements. The study identified that the greatest environmental aspects is the hazardous waste of creosote impregnated power poles and PCB-contaminated oil. No major improvements in the waste management has been. Focus has then been to examine options to replace the hazardous materials for new installations. It has been found several different options to the creosote power pole that all have different effects on the environment and there are therefore no obvious alternative. PCB-contaminated oil are currently not allowed in the grid but as it means a big expense to replace dispensations has been distributed to the owners of the power grid until it has been rebuilt.

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  • 44.
    Andersson, Andreas
    et al.
    University West, Department of Engineering Science, Division of Computer, Electrical and Surveying Engineering.
    Leinonen, Markus
    University West, Department of Engineering Science, Division of Computer, Electrical and Surveying Engineering.
    Projektering och elkvalitetsstudie av laddstationer för elfordon2017Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    In the last couple of years, the evolution of plug-in electric cars has contributed to an increasing need of well-built charging infrastructure. This does not only require that the fair amount of charging stations needs to match the increasing demand, but the growing amount of charging station could also affect the power quality in the grid itself due to the technology used today.

    The objective of the first part of the project was to deliver a complete installation plan and project basis of two AC charging stations for electric vehicles, planned in the city of Kungälv. The second part of the project was focused on studying the effects of DC fast charging of electric vehicles, with power quality in mind. This study was based on readings obtained from measuring the power quality at an existing DC fast charging station in Kungälv, as well as available publications within the area of the subject. The project planning was conducted in regards to Swedish standards and regulations, as well as to the instructions and expectations of the client, Kungälv Energi. The result was compiled and handed over to the client during the final part of the project. The resulting document contained information regarding installation, material and placement as well as approximate cost calculations.

    The power quality study was carried out on a currently installed fast charging station located in the city of Kungälv, using power quality measuring instruments provided by Kungälv Energi and Metrum Sweden AB. The result was a power quality report, compiled according to Swedish Energy Markets Inspectorate, where all requirements concerning power quality were met. The data was also analyzed manually, to further investigate the effects of DC fast charging. The study shows no immediate signs of negative impact of the power quality in the nearby grid caused by the fast charging stations within the project. There were signs of harmonics caused by the charging stations, but the presence was considered low. The usage frequency is however a major factor when investigating the power quality affection of the charging station. This results in a conclusion that is not generally applicable.

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  • 45.
    Andersson, Anette
    et al.
    University West, Department of Engineering Science, Division of Industrial Engineering and Management, Electrical- and Mechanical Engineering.
    Bojort, Daniel
    University West, Department of Engineering Science, Division of Industrial Engineering and Management, Electrical- and Mechanical Engineering.
    Nätplan för fördelningsstation M5 Hålta2018Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    In the area of Tjuvkil on the west coast, about 16 kilometers west of Kungälv city, a new residential area is about to be planned for about 140 new houses and holiday houses turned into permanent houses. A grid plan will therefore be made to investigate if there are any flaws to consider for the 10 kV-net, before and after the introduction which the new load will cause on behalf of the houses, plus extra space for the installation of an amount of charging posts.

    The purpose of this thesis is to compile the grid plan which will make the groundwork for the power distribution grid under the M5 transformer Hålta, which contains the areas for the new settlement. Backed up by the software dpPower this work will point out the flaws such as thin cables where large load currents and voltage drop occur, and also the statistics for interruption for the five outgoing lines from M5. This work also shows the status for the transformer in Hålta and how the surrounding grids status will be affected during their backup of emergency power for the M5. This work shows the grid status in the 4 steps as present status, with new load, emergency power and solutions.

    The thesis's evaluation of M5 Hålta will result in a suggested change of cable for the line L501 to Tjuvkil, which will decrease voltage drop and lower load current to avoid interruptions on the grid. Emergency power is lacking for a large-scale consumer and can be fixed with a looped feeding instead of a single line feeding on line L503. The transformer M5 in Hålta is already heavy loaded and in need to be replaced by a larger transformer later on. The thesis gives a suggestion on how to connect the adjacent transformers M1, M4 and M6 for emergency power.

  • 46.
    Andersson, Carl
    et al.
    University West, Department of Engineering Science, Division of Mathematics, Computer and Surveying Engineering.
    Bränfeldt, Jonathan
    University West, Department of Engineering Science, Division of Mathematics, Computer and Surveying Engineering.
    Användare, hot och beteende i nätverket2020Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This thesis contains a security analysis primarily focusing on the users and their behaviors in relationship to their daily IT usage.

    The thesis was possible due to the help via an international e-commerce company leading in their field of operation.

    The company which this thesis has been carried out with is a leading international e-commerce company in its industry. Their Swedish office has 35 employees all of whom use IT-related equipment daily in their daily tasks. Their interest is to learn more about IT security and in particular internal security.

    Through research of both network devices, user devices, interviews and a survey, the security on layer 2 as well as the users behaviour and knowledge have been examined. Following this research, results have been extracted regarding possible vulnerabilities and recommendations for further development within the area to improve the matters of today.

  • 47.
    Andersson, Carl Fredrik
    University West, Department of Engineering Science.
    50 kVA eller 100 kVA: En teknisk och ekonomisk jämförelse av distributionstransformatorer2010Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Rapporten utreder om distributionstransformatorer med märkeffekten 50 kVA i Vattenfall Eldistribution AB:s elnät kan avskaffas till förmån för märkeffekten 100 kVA. Transformatorer med märkeffekten 50 kVA förekommer vid nedtransformering av spänningen från 22 kV och 11 kV till hushållens huvudspänning 0,4 kV.

    50 kVA-transformatorer skiljer inte särskilt mycket från transformatorer med den högre märkeffekten i fråga om storlek och pris, och de bedöms kunna bytas ut utan större praktiska svårigheter.

    Fördelen med 100 kVA är att de elektriska belastningsförlusterna blir lägre i och med den högre märkeffekten. Dessutom innebär ett byte vissa elkvalitetsförbättringar.

    Nackdelarna med 100 kVA är att de elektriska tomgångsförlusterna är högre och att inköpspriset är högre än för 50 kVA. I övrigt kan kostnaderna likställas för de två alternativen.

    Endast kostnader för aktiva effektförluster berördes i rapporten då de ekonomiska kostnaderna för reaktiva effektförluster kunde försummas för de aktuella transformatorerna.

    För att nå ett svar på frågan om det kan vara lönsamt att avskaffa 50 kVA-transformatorerna studerades fem verkliga fall i Vattenfalls svenska elnät. Dessutom studerades eventuella elkvalitetsvinster med ett byte.

    Svaret blev att inte för något av de fem studerade fallen var det lönsamt med ett byte till 100 kVA-transformator. Rörande elkvalitetsaspekten blev svaret att ett byte visserligen innebär en skillnad men att andra faktorer oftast har större betydelse. Rapportens rekommendation blev att behålla 50 kVA-transformatorn i distributionsnätet. 

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  • 48.
    Andersson, Christoffer
    et al.
    University West, Department of Engineering Science, Division of Computer, Electrical and Surveying Engineering.
    Andersson, Pontus
    University West, Department of Engineering Science, Division of Computer, Electrical and Surveying Engineering.
    Beredning av distributionsnät Myren-Torseröd i Tanum2016Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This report will focused on how the preparatory work between Myren-Torseröd in Tanum will proceed. On behalf of Ellevio AB, the preparation and construction company Trolk EL & Tele AB shall weatherproof an area between Galtö-Torseröd in Tanum. This report will only include the distribution 0,4-24 kV in the area between Myren-Torseröd. The existing overhead line network will be dismantled and replaced with underground cables. Even existing substations and pole stations to be scrapped and replaced with new ones. During the preparatory work, there have been field visits to get an overview of the field of processing operations, and to measure the position of e.g. substations. To have access to the ground the preparation worker must sign contracts with landowners, and shall also seek authorization from the County Administrative Board, the transport department and municipality. The entire preparation work in this project includes 68 customers.

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  • 49.
    Andersson, Daniel
    University West, Department of Engineering Science, Division of Industrial Engineering and Management, Electrical- and Mechanical Engineering.
    Metodutveckling för analys av driftstörningar relaterade till planerade arbeten i Vattenfalls distributionsnät2020Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This bachelor's thesis was performed on behalf of Vattenfall Eldistribution AB as a continuation of a previous thesis (reference thesis) covering the same subject. The project intended to expand on that thesis by developing a replicable method aimed for analysis of incidents with direct association to planned work; in this project defined as a "consequential incident". During assessment of a likely consequential incident, two additional filter criteria were also included in this project: Incidents originating from tests performed on protective relays and incidents registered for sole substations.

    The method is mainly conceptual and is composed of an analytic tool programmed with VBA through Microsoft Excel, intended to be demonstrated only for 2017. The workflow begins with importing relevant raw data from Vattenfall's database systems, including 2 292 out of 2 501 switching schedules and 4 607 out of 11 263 incidents. The function for generating "preliminary matches" is designed to compare each switching schedule to each incident. A matching event is triggered if an incident's start time coincides within a switching schedule's time frame; in conjunction with occurring on the same primary feeder station as the planned work. Each match is assigned an ID and one out of seven categories; each reflecting a match's likelihood of being a consequential incident; partly based on parameters gleaned from a switching schedule's work description, partly by certain keywords sometimes located in an incident's fault report comment.

    534 preliminary matches were assessed through a designated analysis user form resulting in a span of 51 to 82 consequential incidents; constituting an increase of 59–256 % compared to the reference thesis' 32, year 2017. The reference value of SAIDI amounted to 0,82 minutes whereas the new SAIDI amounts to 1,71–4,43 minutes (+109–540 %), of which one minute was due to faults during relay tests. Extrapolation based on these ratios, and reference values from 2015–2018, resulted in a yearly average of 68 incidents and 4,76 SAIDI-minutes; an approximate cost of 262 Mkr (55 Mkr per SAIDI-minute).

    The project's intentions are considered reached and the tool has proved a high user friendliness, functionality, and future development flexibility. A lack of quality assured data was the project's main challenge, which has resulted in rather unreliable results. This could be amended by furthermore only allowing data from reliable sources like NetBas DarWin. Vattenfall could also assist future analysis by internally defining tangible intentions and ambitions concerning this subject; mainly by determining its relevance to the company's exponentially decreasing goals regarding their quality and continuity of supply.

  • 50.
    Andersson, Daniel
    et al.
    University West, Department of Engineering Science, Division of Industrial Engineering and Management, Electrical- and Mechanical Engineering.
    Back, William
    University West, Department of Engineering Science, Division of Industrial Engineering and Management, Electrical- and Mechanical Engineering.
    Utvärdering för att främja AMS i relation till planerat SAIDI i Vattenfalls distributionsnät2019Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Vattenfall Eldistribution AB is striving towards maintaining high service reliability for customers in their distribution grid. This ideally implicates that power outages cannot occur from neither unpredictable disturbances, nor as a direct result of planned work. The supervisory authority for the energy markets, The Swedish Energy Markets Inspectorate (Ei) regulates and limits Vattenfall’s revenue based on the key performance indicator (KPI) System Average Interruption Duration Index (SAIDI). To improve SAIDI it is preferential using working methods causing no power outages, where the method of Live Working (AMS) is included.

    Vattenfall’s distribution grid is divided into ten contract areas where one entrepreneur, after leaving a suitable proposal, wins the solicitation process for either of these contract areas’ service agreement. A single entrepreneur (Entrepreneur A) holds all service agreements during this study’s interval (year 2016–2018). There is a high prevalence of compactly built substations today, usually built with fully insulated switchgear, which due to a lack of working clearance and cramped working spaces inhibit the prospect for AMS. A high prevalence of underground cable also inhibits AMS due to difficulties connecting bypassing units.

    A statistical evaluation and compilation of switching orders was conducted and used to determine how AMS is affected by prerequisites and limitations in relation to entrepreneurs, contract areas and substations. The number of established switching orders was 2969 during the year of 2018, of which 17,48 % were established as AMS; which is a decline since year 2016 where 22,86 % of 2616 swiching orders were established as AMS. An increase in investment projects may be a cause for this decline, due to their lower amount of AMS compared to maintenance work. Lowest SAIDI was found in Contract Area 5, 6 and 9, where further studies regarding prerequisites for AMS could be considered, with intention to implement eventual findings in areas with high SAIDI, for instance Contract Area 1 and 4.

    Vattenfall should increase cooperation and diaglogue between and themselves and solicited entrepreneurs with the aim of increasing the number of switching orders established as AMS. Entrepreneurs posess highly valuable knowledge and experience regarding risk identification and future construction possibilities. Goal cards in the service agreement could also contain KPI’s where a certain quota of AMS may entail a suitable bonus. Only 13,75 % av all unique entreprenurs conducted work using AMS year 2018. Vattenfall should research the cause for this decline and evaluate the profitability of substantially subsidizing AMS education and equipment for entrepreneurs, which could be compared to increased costs due to power interruptions from dead working (AUS), like customer notifcations and compensation.

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