Selaus koulutusohjelman mukaan kokoelmassa VäitöskirjatSchool of Energy Systems, Sähkötekniikka

    • Acoustic Emission Testing of Multilayer Ceramic Capacitors 

      Levikari, Saku
      Acta Universitatis Lappeenrantaensis (Lappeenranta-Lahti University of Technology LUT, 25.03.2022)
      Capacitors are among the three fundamental passive electrical components alongside inductors and resistors. They are found in nearly every electronic circuit, with the function of storing electrical energy and filtering ...
    • Active residential customer in a flexible energy system — a methodology to determine the customer behaviour in a multi-objective environment 

      Belonogova, Nadezda
      Acta Universitatis Lappeenrantaensis (Lappeenranta University of Technology, 05.12.2018)
      The transformation from passive into active end customers in modern energy systems has already started in many European countries, and it is a long process. The first step to engage residential customers to be active actors ...
    • Analyses and comparison of energy systems and scenarios for carbon neutrality – Focus on the Americas, the MENA region, and the role of geo-technologies 

      Aghahosseini, Arman
      Acta Universitatis Lappeenrantaensis (Lappeenranta-Lahti University of Technology LUT, 23.02.2023)
      Energy systems underpin the economic growth of nations but are contributing to worsening climate change in the current state dominated by fossil fuels. Transitioning to a fossil-free renewables-based energy system is ...
    • Analysis of theory and methodology used in determination of electric motor drive system losses and efficiency 

      Kärkkäinen, Hannu
      Acta Universitatis Lappeenrantaensis (Lappeenranta-Lahti University of Technology LUT, 23.04.2021)
      This research is divided into two main parts: loss determination of motors, converters, and motor drive systems and determination of measurement uncertainty. With its accurate measurements and data analysis, the work ...
    • Anomaly detection in cyber-physical applications 

      Gutierrez Rojas, Daniel
      Acta Universitatis Lappeenrantaensis (Lappeenranta-Lahti University of Technology LUT, 25.05.2023)
      Anomaly detection is a crucial task in many industrial environments as it enables a safer and more reliable operation of different processes; it is usually seen as a separate process from the industrial system design. ...
    • Applicability of GaN high electron mobility transistors in a high-speed drive system 

      Järvisalo, Heikki
      Acta Universitatis Lappeenrantaensis (Lappeenranta-Lahti University of Technology LUT, 10.02.2020)
      Lossless operation and instantaneous switching are properties of an ideal power electronic switch. Wide band gap devices based on gallium nitride (GaN) are the current peak performers in regard to losses and switching ...
    • Application of software-defined radio for power-line-communication-based monitoring 

      Poluektov, Anton
      Acta Universitatis Lappeenrantaensis (Lappeenranta-Lahti University of Technology LUT, 07.02.2020)
      Power line communication (PLC) is an established telecommunication technology. A PLC-based communication system has the advantage of securing data. transmission over already existing power line networks. In this way, an ...
    • Assessing the applicability of low voltage direct current in electricity distribution : key factors and design aspects 

      Karppanen, Janne
      Acta Universitatis Lappeenrantaensis (Lappeenranta-Lahti University of Technology LUT, 20.11.2020)
      In many countries, the electricity distribution companies are facing the challenge of how to develop the networks effectively and respond to the future needs of societies. Changes in the electricity end use, aging network ...
    • Control design issues in grid-connected single -phase converters, with the focus on power factor correction 

      Honkanen, Jari
      Acta Universitatis Lappeenrantaensis (Lappeenranta-Lahti University of Technology LUT, 25.09.2020)
      Electrical equipment is most commonly powered from a mains connection. The mains alternating voltage is rectified, isolated, and regulated in a power supply. The power supply acts as an interface between the mains voltage ...
    • Design and control of a permanent magnet bearingless machine 

      Jaatinen, Pekko
      Acta Universitatis Lappeenrantaensis (Lappeenranta-Lahti University of Technology LUT, 29.11.2019)
      The overall efficiency of high-speed applications can be improved by applying direct drive motor technology. Operating in the high-speed region is a demanding task for the traditional bearing technology. With active magnetic ...
    • Energy efficient hydrogen production by water electrolysis 

      Koponen, Joonas
      Acta Universitatis Lappeenrantaensis (Lappeenranta-Lahti University of Technology LUT, 28.02.2020)
      Hydrogen is the most abundant element in the universe. On Earth, it not only forms water molecules, but also commonly combines with carbon into hydrocarbons that power the current world economy. The use of these natural ...
    • Energy security evaluation for the present and the future on a global level 

      Azzuni, Abdelrahman
      Acta Universitatis Lappeenrantaensis (Lappeenranta-Lahti University of Technology LUT, 13.10.2020)
      Energy Security is a universal concern for all stakeholders and achieving energy security is a crucial objective for all societies. Therefore, energy security became a major part of national security with the ability to ...
    • Evaluation of failure mechanisms in electronics using X-ray imaging 

      Ingman, Jonny Mikael
      Acta Universitatis Lappeenrantaensis (Lappeenranta-Lahti University of Technology LUT, 30.09.2022)
      Multilayer ceramic capacitors and thick film resistors are widely used in electronic circuits for frequency converters because of their small size and volumetric efficiency. In addition, as a result of the current trend ...
    • Evaluation of open-source FEM software performance in analysing converter-fed induction machine losses 

      Zaheer, Minhaj
      Acta Universitatis Lappeenrantaensis (Lappeenranta-Lahti University of Technology LUT, 28.01.2022)
      Converter-fed induction machines are widely used in variable speed applications. They are renowned for their good controllability, low manufacturing cost, and robustness. These machines are used in various applications ...
    • Ferrite Permanent Magnet Hysteresis Loss in Rotating Electrical Machinery 

      Egorov, Dmitry
      Acta Universitatis Lappeenrantaensis (Lappeenranta-Lahti University of Technology LUT, 15.11.2019)
      Electrical machines with permanent magnets (PMs) find numerous applications in present energy-efficient technologies. A reasonable compromise in terms of costs and efficiency makes electrical machines with ferrite PMs a ...
    • Framework for digitalizing different industrial sectors via the Internet of Things 

      Ullah, Mehar
      Acta Universitatis Lappeenrantaensis (Lappeenranta-Lahti University of Technology LUT, 18.12.2023)
      The Industrial Revolution 4.0 (IR4.0) refers to the current era of technological advancements that are transforming the different sectors of productive activities. It brings what is called Industry 4.0 characterized by the ...
    • Grid Support by Battery Energy Storage System Secondary Applications 

      Alaperä, Ilari
      Acta Universitatis Lappeenrantaensis (Lappeenranta-Lahti University of Technology LUT, 13.12.2019)
      Global developments in renewable energy and energy efficiency of the power consumption present challenges to maintain the frequency stability of the electricity grids. The objective of the research is to investigate how ...
    • Heuristic-Based Packetized Energy Management for Residential Electricity Demand 

      Hussain, Hafiz Majid
      Acta Universitatis Lappeenrantaensis (Lappeenranta-Lahti University of Technology LUT, 07.06.2023)
      The unprecedented growth of distributed energy resources (DERs) has brought limitless opportunities to reshape the energy infrastructure and instigate urgent reforms for technoeconomic advancements, business models, ...
    • Identification of magnetically levitated machines 

      Vuojolainen, Jouni
      Acta Universitatis Lappeenrantaensis (Lappeenranta-Lahti University of Technology LUT, 16.06.2020)
      Magnetically levitated machines use magnetic levitation to maintain the separation between the bearing races. They offer various benefits compared with other types of bearings: no contact between the bearing races, the ...
    • Improving the DC-DC Power Conversion Efficiency in a Solid Oxide Fuel Cell System 

      Hiltunen, Jani
      Acta Universitatis Lappeenrantaensis (Lappeenranta-Lahti University of Technology LUT, 29.11.2019)
      The solid oxide fuel cell (SOFC) is a promising technology for combined heat and power generation as it provides low local emissions, high efficiency, and fuel flexibility. However, the unique electrical characteristics ...