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  • 151.
    Wahl, Daniel
    et al.
    University West, Department of Engineering Science, Division of Industrial Engineering and Management, Electrical- and Mechanical Engineering.
    Kärrå, Michael
    University West, Department of Engineering Science, Division of Industrial Engineering and Management, Electrical- and Mechanical Engineering.
    Ö-drift med mobil reservkraft i nät med småskalig elproduktion2018Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This bachelor thesis is carried out on behalf of Jönköping Energi. Their general idea is to provide an uninterrupted power supply also when maintenance is done in substations. They have diesel generators that are responsible for the power supply while service is being carried out and island operation occurs. In recent years, there has been an increase in installed solar PV systems in Sweden and thus also in the grid that is supplied by Jönköping Energi. This may cause complication in conjunction with the island operation with the diesel generator as the main power source.

    The problem that might occur in steady state is if the PV plants would produce more power than the diesel generator, then a reverse power situation occurs. This would trip the reverse protection of the generator and disconnect the power supply. Through a case study with data collected from a substation at Jönköping Energi it is shown how the production from the PV plants varies. The consumption of power from the substation is significantly higher than that produced power from the PV plants. Considering the ongoing increase of installed PV plants, however, it is not possible to ignore the fact that problems may arise within a number of years. It is also important to consider that diesel generators should not be under loaded as the diesel engine will have a carbon buildup and the operation will deteriorate while also reducing the life time of the engine. Dimensioning of diesel generators for island operation will therefore become considerable more important and a guide has been made.

    To investigate the dynamic limitations of the diesel generators step responses are investigated from the load tests carried out by the manufacturer. The step responses are compared to what theoretically can happen in the grid. That of most importance is large PV systems or if a disturbance causes all plants to turn off or on at the same time. The change in production from the solar cell plants can be seen from the diesel generator as a change in load.

    The two different diesel generators that Jönköping Energi owns have a rated power of 100 and 550 kVA. Step responses indicates that the diesel generators would be able to handle very large fluctuations in the grid. The step response of the 100 kVA unit shows that a load of 0-70 % would not trip any protection on the generator. For the 550 kVA unit, the step response indicates that a load of 0-60 % would not cause any problems. Negative load steps on the other hand, both units will be able handle up to brand effect, this is seen on step responses made from a load of 110 and 108 percent down to zero percent, with no bigger impact on either frequency or voltage.

  • 152.
    Westerdahl, Kristian
    University West, Department of Engineering Science, Division of Industrial Engineering and Management, Electrical- and Mechanical Engineering.
    Utredning gällande utförande av lågspänningsställverk2020Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This thesis has been done on behalf of Bema Elautomatik AB and has been carried out at the Department of Engineering Sciences at University West. The client has expanded its business with assembly, design and planning of low voltage switchgears. An investigation regarding the choice of electric equipment, standards and a new routine verification protocol is thus desired.

    In order to determine the scope of what should be included in the final proposal for a solution, lists are made that show how typical low voltage switchgears should be designed and which electrical equipment and standards that should be included. In addition to this, a routine verification protocol is made based on the information found in standards and a checklist that presently used by the client. The main standards that are investigated in the thesis are IEC 61439-1, IEC 61439-2 and the Swedish electrical installation regulations SS 436 40 00.

    Interviews with relevant personnel are performed to investigate checklists in the client's existing routine verification protocol and to find out what was the basis for the present choice of electric equipment. Based on the interviews, it is clear, among other things, which low voltage switchgear manufacturers the client has worked with before and the experience of different switchgear the staff possess and also wishes from the staff on which manufacturers they should consider to work with.

    A proposal for the routine verification protocol is developed and should be seen as the basis for what is the minimum amount of verification points that must be included in a checklist. More points can be added if deemed necessary by the employer.

    When choosing electric equipment, the main factor is not cost, instead functioning and quality play a greater role. Previously, the client has worked with the switchgear manufacturers Schneider Electric and Eldon, but also Lögstrup and components from Eaton should also be considered for future projects.

    The results from the interviews with staff also showed that work methods that are indirectly affected by the new routine verification protocol must be considered and more staff at the company must be included in these discussions.

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  • 153.
    Wikström, Martin
    University West, Department of Engineering Science, Division of Industrial Engineering and Management, Electrical- and Mechanical Engineering.
    Energilagring med vätgas i Off-Grid-system för en besöksanläggning2019Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This thesis is carried out as a continuation of a pilot study that ÅF in Gothenburg started in 2018. The client is Chalmersfastigheter AB, who plans to construct a visitor facility in Kungsbacka Municipality, in the same area as the existing space observatory. After the building's shape and area were determined, the energy consultancy firm Bengt Dahlgren performed an energy analysis. As a continuation of ÅF's pilot study, an Off-Grid solution to the building will be examined in this thesis. The building should be operated 365 days a year with renewable energy and without being connected to the grid. Solutions with solar cells and short-term storage of battery already exist, but to operate the building during the winter when there is minus degrees (C°) and low solar irridation is the big challenge.

    This thesis intends to dimension a hydrogen system depending on surplus energy from solar cells. The surplus in the summer months is sufficient to generate hydrogen gas via a electrolysis. The hydrogen will be stored in pressure thanks in its own building a safe distance from the visitor facility. The advantage of hydrogen is that there is no loss of energy during storage. The piping system also has a neglectable loss in drop of pressure depending on the length of the pipes.

    After a visit to an existing Off-Grid building in Gothenburg, calculations began. With the help of the PV SOL simulation software, information was produced about solar cell production and the building's consumption every month. After this the operating time of the electrolysis was determined. An excess of sunelectricity of 12 371 kWh/year is sufficient to generate 3 711 kWh of electricity during winter. The efficiency on both the electrolyser and fuelcell is about 50-60 %, which gives a total efficiency of electricty of roughly 30%. The rest is mostly losses in the form of waste heatwater. As it follows, the fuelcell also produce as many kWh in hot water as the number of kWh electricty it generates during operation. This is a major fact that was taken into account when calculations of the buildings yearly electricty consumption where to be determined.

    It is technically possible to operate the planned building of 500 m2 Off-Grid 365 days a year. The fact that both the electrolyser and fuelcell produce excessiv waste heat helps to save electricity on the yearly consumption. A disadvantage with the electrolyser and the fuel cell is the short technical lifespann of approximate ten years.

  • 154.
    Wolnievik, Niklas
    University West, Department of Engineering Science, Division of Industrial Engineering and Management, Electrical- and Mechanical Engineering.
    Projektering och beredning av ett distributionsnät i ett exploateringsområde2018Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This thesis is about how a preparatory works from start to finish. The project comprises a power distribution network in a new residential area with 33 villas, a preschool and an industry property. Parts that power consumption of houses, preschool and an industry has been based on their main fuse. Load current and dimensioning of low voltage cables as high-voltage cables have been developed for the different sections available cable is located. Voltage drop of the various sections for service cables and the supply cables and the voltage dips to subscribers are treated in this report, with the goal of keeping this voltage drop below 4 %. The trigger condition for the different connection routes have been checked to keep the mains as safe as possible. The economic area has been considered, for the selection of the various cables that has been used during the operation. The work also deals with the selection of materials from the cable distribution cabinets to fuses. Several different agreements have been treated, map types from the excavation map to high voltage map has been developed. In a project there are several costs which are essential to obtain the final cost. Some of these costs have been treated as: P2-calculation is made and valuation protocol for the various land owners has been developed. A presentation of the different applications used within a preparation has been included, which can help and facilitate the work of processors. The result of the preparatory works comprises a new 12/0.4 kV grid station, nine new cable distribution cabinets and 155 meters 12 kV HV cable and 4 087 meters 0.4 kV low voltage cable. Excavation distance will be 1 980 meters long, which excavate up to the property line, where the property owner is responsible for the excavation. The Grid Station has been placed strategically so that the excavation routes are minimized, and the voltage dips is held. Cable distribution cabinets have also been placed strategically to provide all subscribers with power and with the voltage dip in mind, the length of the service lines has been kept down. The cost of the project is estimated at SEK 2.1 million

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  • 155.
    Yu, Huanyu
    University West, Department of Engineering Science, Division of Industrial Engineering and Management, Electrical- and Mechanical Engineering.
    3D Scanning and Modeling with the use of a Mobile Robot2017Independent thesis Advanced level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    In recent years, the number of mobile robot has increased rapidly. They can not only be used for carrying out tasks in hostile work environment, but also make people's daily life convenient. In the meantime, the rise of 3D technology has changed people's life with its applications in the fields of industrial life and daily life. Therefore, the combination of 3D technology and mobile robot has enormous potentials.

    The objective of this project is to create a model of an object or indoor environment with the help of a mobile robot. A 3D scanner which can be attached on a mobile robot will be used for scanning. With the depth information collected, the point clouds can be gotten. The basic way of reconstructing the model is called Kinect Fusion, it uses Kinect camera to scan the area and creates a model with help of Iterative Closest Point algorithm and Truncated signed distance function which will be introduced in section 2.5. The registration of the point clouds and the localization of the camera can be realized by using ICP algorithm. The software which is used to implement these methods is Visual Studio 2012 with OpenCV and KinectFusion library.

    As the camera should be able to be used on any kind of robot, the aim of these tests is to find a better way to get a high quality model of the area. In this paper, two main experiments have been done. One of them is about scanning a target object from different distances. There will be errors between object actual size and its model size. And the relationship between the errors and the distances will be found out. The other one is focused on the movement of the camera. There are two scenarios in this experiment. The first one is to move the camera with different speed and the other scenario is to scan an object by moving the camera around the object. The result shows that the robot attached with the camera should move slowly so that the camera can capture enough frame images for the model. And keep scanning one object by moving the camera around it can't make the model looks better but worse.

  • 156.
    Yu, Liang
    University West, Department of Engineering Science, Division of Industrial Engineering and Management, Electrical- and Mechanical Engineering.
    Automatic obstacles avoidance pickup and placement path generation achievement with scanning of environment for an industrial robot2019Independent thesis Advanced level (degree of Master (One Year)), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Industrial robots are widely used in modern industry fields because of the development of robot technology. In robot palletizing or bin-picking application, robot needs to automatically generate path for achieving robot picking and placing operation even if there exist obstacles. This project is to design and test a robot system that can move without collisions in a changeable environment. And communication is realized between two computers through an industrial communication protocol.

    ROS has been chosen as a simulation platform for the robot path planning simulation as it has some independent advantages, like open-source, supporting multiple programming languages, integrating a lot of open source tools and advanced algorithms. ROS MoveIt! software is used for motion planning, operation control, 3D perception, kinematic solution, collision detection, and so on. Through RRT method, robot path planning is achieved and through Flexible Collision Library, collision detection is achieved. For robot system test experiments and results, taking ABB IRB 2600 robot as a test industrial robot, a robot simulation system in ROS is designed and set up to realize obstacles free picking and placing path planning task of the robot.

    Firstly, for obtaining external obstacles information, Kinect V1 camera is used and calibrated for eliminating distortion and obtains colour image and depth image. Secondly, by using Point Cloud Library, the images are transformed to point cloud images with filtering for eliminating noise. Thirdly, by using OctoMap library, the scene including obstacles are created to 3D occupancy map. Furtherly, according to the map, robot obstacles avoidance pickup and placement operation is achieved in ROS.

    Finally, for testing and evaluating the system, the robot model, a pickup object and an obstacle model are created in ABB RobotStudio software which is the same as ROS's and further achieves co-simulation motion in ROS and ABB RobotStudio by ROS TCP/IP socket program. By running path planning in ROS, the robot achieves obstacle avoidance path planning and pickup and placement operation in ABB RobotStudio.

1234 151 - 156 of 156
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