Now showing items 155-174 of 191

    • Seasonal storage of energy at UiT the arctic university of Norway in Narvik 

      Alfnes, Dennis (Master thesis; Mastergradsoppgave, 2023-05-22)
      The thesis examines which energy production methods are suitable together with seasonal storage of energy at UiT the arctic university of Norway in Narvik. Nordkraft has provided the subject which has been examined. The location of UiT Narvik together with its areas and storage volumes have been examined for what power production methods and energy storage methods are suitable for this location. ...
    • Secondary Network Throughput Optimization of NOMA Cognitive Radio Networks Under Power and Secure Constraints 

      Vo, Van Nhan; Viet Hung, Dang; Tran, Hung; Ha, Dac-Binh; Le, Cong; Ho, Tu Dac; Chakchai, So-In (Journal article; Tidsskriftartikkel; Peer reviewed, 2023-03-31)
      Recently, the combination of cognitive radio networks with the nonorthogonal multiple access (NOMA) approach has emerged as a viable option for not only improving spectrum usage but also supporting large numbers of wireless communication connections. However, cognitive NOMA networks are unstable and vulnerable because multiple devices operate on the same frequency band. To overcome this drawback, ...
    • Security Constrained Unit Commitment and Economic Dispatch applied to the Modified IEEE 39-bus system Case 

      Tricarico, Gioacchino; Azuara-Grande, Luis Santiago; Wagle, Raju; Gonzalez-Longatt, Francisco; Dicorato, Maria; Forte, Giuseppe; Rueda, Jose Luis (Journal article; Tidsskriftartikkel, 2022-12-09)
      The operation schedule of the power generation units in electrical power systems is determined by the optimisation problem known as unit commitment (UC), aiming at minimising the total cost considering the generation constraints. To obtain a feasible solution from the network perspective, the security-constrained UC (SCUC) problem has been defined to embed the network constraints in the optimisation ...
    • Security Constrained Unit Commitment and Economic Dispatch by AC Sensitivity Factors 

      Tricarico, Gioacchino; Wagle, Raju; Azuara-Grande, Luis Santiago; Gonzalez-Longatt, Francisco; Dicorato, Maria; Forte, Giuseppe; Rueda, Jose Luis (Journal article; Tidsskriftartikkel; Peer reviewed, 2022-11-09)
      The dispatch schedule of the electrical power plant units is the result of the solution to the unit commitment optimisation problem, and it minimises the cost of production considering pre-defined technical limits. The security-constrained unit commitment problem has been defined as including the network constraints in the previously mentioned optimisation problem to obtain a feasible power system ...
    • Smart grid solutions for integration of renewable energy in remote communities 

      Hoff, Bjarte (Conference object; Konferansebidrag, 2017)
    • Smarte løsninger for integrering av fornybar energi 

      Hoff, Bjarte (Konferansebidrag; Conference object, 2017)
    • Smarte nett - Framtidas fleksible energisystem 

      Hoff, Bjarte (Conference object; Konferansebidrag, 2016)
    • Smarte nett - Framtidas fleksible energisystem 

      Hoff, Bjarte (Konferansebidrag; Conference object, 2016-03-16)
    • Sol vinkel estimator. Solpanel rig med dobbel akse orientering 

      Mikkelsen, Rolf Olaf (Master thesis; Mastergradsoppgave, 2019-06-28)
      Denne rapporten presenterer design og simuleringer av en toakset solcellerigg. Denne bestpunktsporingen riggen fungerer utelukkende basert på utgangseffekten til solcellepanelet montert til det. Det bruker ikke noen solsensor til å orientere solcellepanelet. Posisjonen til solen er beregnet basert på tid og stedsinformasjon. Siden dette solpanelet vil bli montert her på UiT, Norges Arktiske Universitet, ...
    • Solar angle optimizer 

      Haque, Md Emranul (Master thesis; Mastergradsoppgave, 2023-05-22)
      The demand for renewable energy sources has increased significantly in recent years due to the growing concerns about climate change and environmental sustainability. Solar energy has emerged as one of the most promising and widely used renewable energy sources. However, the efficiency and output of solar energy systems depend on various factors, including the position of the sun, the angle ...
    • Solvinkel optimaliserer 

      Nilsen, Bjarne (Master thesis; Mastergradsoppgave, 2021-05-18)
      Snø og andre ting kan reflektere lys på solcellepanelene slik at de produsere mer energi. Refleksjonene kan gjøre slik at den optimale vinkelen til panelene ikke er rett mot solen. Denne rapporten går fort igjennom noen forslag til optimaliseringsalgoritmer for vinklene til solcellepanelene. Videre går den dypere inn på en algoritme som heter «test og sjekk». Kort fortalt går denne algoritmen ...
    • Stabilization of Non-Cooperative Satellites in Low Earth Orbits using Inter-Satellite Atmospheric Drag 

      Oland, Espen; Kristiansen, Raymond (Chapter; Bokkapittel, 2023-08-07)
      This paper presents a novel solution to the problem of stabilization of non-cooperative satellites in low Earth orbits, which utilizes inter-satellite aerodynamic drag effects for generation of aerodynamics moments in the wake of a controlled satellite. Hence, by altering the position of a smaller controlled satellite, we are able to change the wake region and thus provide aerodynamic moments for ...
    • Study & Analysis of Power Switches with reverse voltage blocking capability 

      Mughal, Babur Zaman Khan (Master thesis; Mastergradsoppgave, 2021-05-25)
      This thesis hovers over the basic introduction to Silicon Carbide (Metal Oxide Semiconductors Field-effect Transistor) MOSFET switches and the circuit designing of Current Source Invertors using SiC MOSFET switches. The thesis covers the basic grounds for all the steps needed in the implementation of hardware design for half bridge, full bridge and three phase CSIs in the future. Firstly, a ...
    • Study and Analysis of Alternative Power Switches with Reverse-Voltage Blocking Capability 

      Rashid, Muhammad Zarrar (Master thesis; Mastergradsoppgave, 2022-06-02)
      The current source inverters are becoming competitors of the voltage source inverters largely due to the reduced complexity, improved reliability and potentially improved efficiency. This paper describes the functionality of current source inverters and why they’re becoming increasingly popular. It also discusses about the benefits of SiC over other semiconductors and the use of SiC MOSFETS with ...
    • A study of hydro and pumped storage hydropower in Northern Norway 

      Maharjan, Sujan; Ampim, Emefa Akua (Master thesis; Mastergradsoppgave, 2017-06-15)
      "The role of renewable sources of energy in combating climate change cannot be over-emphasized. Profound measures taken especially by the European Union (EU) in reducing global rising temperatures has seen massive development of renewable sources of energy such as solar and wind. This strategic plan taken by the EU has led to the an increase in national efforts to promote further development of ...
    • Study of Inter Area Oscillations Using Phasor Measurement Units 

      Olsen, Henrik (Master thesis; Mastergradsoppgave, 2021-05-18)
      Low-frequency oscillations in the power system have major repercussions on power system stability and the objective of maximum power transfer. Local and global control strategies have been developed to dampen and impede these oscillations. A modern local control strategy is supplying the automatic voltage regulation (AVR) of the generator with a power system stabilizer (PSS). Modern global control ...
    • Subsumption architecture applied to flight control using composite rotations 

      Oland, Espen; Andersen, Tom Stian; Kristiansen, Raymond (Peer reviewed; Tidsskriftartikkel; Journal article, 2016-03-19)
      In this paper the subsumption theory is applied to flight control through composite rotations where multiple tasks can be defined as simple rotations. The tasks can then be arranged as a hierarchy, where the primary task is always fully pursued, and conflicting lower level tasks are removed by the primary rotation. The concept is applied to a group of uavs that move through an urban terrain while ...
    • Swedish first-year engineering students’ views of mathematics, self-efficacy and motivation and their effect on task performance 

      Tossavainen, Timo; Rensaa, Ragnhild Johanne; Johansson, Monica (Journal article; Tidsskriftartikkel; Peer reviewed, 2019-08-29)
      We examine a group (N = 88) of Swedish first-year engineering students, their motivation, self-efficacy, and beliefs about the nature of mathematics, and how these relate to their task performance in mathematics. In our data, engineering students who emphasized the exact reasoning in their view of mathematics performed significantly better in a set of mathematical tasks than those who emphasized ...
    • Take-Home Exams in University Mathematics and Science Subjects: Some Ethical Considerations 

      Rensaa, Ragnhild Johanne; Kristiansen, Raymond (Journal article; Tidsskriftartikkel; Peer reviewed, 2024)
      This article addresses some challenging perspectives related to offering take-home exams in mathematics at university level. The challenges arose during work on a previous article where four perspectives originating from Bjerrum Nielsen’s framework (2003) were used to analyze universities’ assessment methods during the Covid lockdown in our country. The perspectives had some ethical considerations ...
    • Technical Challenges and Solutions of a three-phase bidirectional two stage Electric Vehicle charger 

      Mughal, Babur Zaman Khan (Master thesis; Mastergradsoppgave, 2022-05-15)
      The sustainability of the power grid owing to the building strain of the ever-growing demand for electrical energy urges innovative and more practical solutions that enable active participation of end-users in stable and reliable management of power systems. One of the emerging projections of such a two-way exchange of electrical power between the grid and consumers is the developing field of ...