Search for dissertations about: "NEE"

Showing result 21 - 25 of 59 swedish dissertations containing the word NEE.

  2. 21. Protection for Multiterminal HVDC Grids - A Digital Contribution

    Author : Ilka Jahn; Staffan Norrga; Hans-Peter Nee; Dirk Westermann; KTH; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; HVDC transmission; power system protection; IED; real-time systems; test bench; field programmable gate array; open-source hardware; open-source software; power engineering education; Electrical Engineering; Elektro- och systemteknik;

    Abstract : The aim of this thesis is to (1) enhance understanding of mechanisms that are important for the protection of high-voltage direct-current (HVDC) grids, and (2) suggest possible technical solutions. To that end, digital technologies were used both in simulation, as well as in a laboratory environment. READ MORE

  4. 22. Integrated Compact Drives for Electric and Hybrid Electric Vehicles

    Author : Lebing Jin; Hans-Peter Nee; Staffan Norrga; Oskar Wallmark; Robert Pilawa-Podgurski; KTH; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; distributed control; electric vehicle; energy storage capability; integrated motor drive; modular converter; modulation; power losses; stacked polyphase bridges converter; switching frequency; Electrical Engineering; Elektro- och systemteknik;

    Abstract : To develop more competitive solutions, one of the trends in the development of drive systems for electric and hybrid electric vehicles (EVs/HEVs) is to integrate the power electronic converter and the electric motor. This thesis aims to investigate the performance and the operation of modular converters in integrated motor drive systems for EVs/HEVs. READ MORE

  5. 23. Ultrahigh-Voltage Silicon Carbide Device Performance, Requirements, and Limitations in High-Power Applications

    Author : Daniel Johannesson; Hans-Peter Nee; Staffan Norrga; Muhammad Nawaz; Alberto Castellazzi; KTH; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; 4H-SiC; Current Filamentation; Device Characterization; Dynamic Avalanche; JTE Structure; Junction Termination Extension Design; SiC BJT; SiC GTO Thyristor; SiC IGBT; SiC MOSFET; SiC PiN Diode; Silicon Carbide; TCAD Simulation; Wide bandgap device; Electrical Engineering; Elektro- och systemteknik;

    Abstract : The increased awareness of the on-going climate change accelerates the electric energy system transformation from fossil-fueled power sources towards systems with larger portions of renewable energy sources. Moreover, the grid infrastructure requires reinforcements to cope with increasing electrical energy demand. READ MORE

  6. 24. Multi-terminal HVDC protections based on transient line modeling

    Author : Niclas Johannesson; Staffan Norrga; Hans-Peter Nee; Jef Berteen; KTH; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; HVDC transmission; HVDC protection; traveling wave protection; MTDC protection; Electrical Engineering; Elektro- och systemteknik;

    Abstract : High voltage direct current (HVDC) is considered one of the critical technologies required for the power system to enable the transition toward renewables. With an increasing geographical density of HVDC converters, there is a potential for optimization by connecting more than two converters into a shared DC transmission system, thus forming a multi-terminal HVDC (MTDC) system. READ MORE

  7. 25. Aspects on Dynamic Power Flow Controllers and Related Devices for Increased Flexibility in Electric Power Systems

    Author : Nicklas Johansson; Hans-Peter Nee; Göran Andersson; KTH; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Adaptive Control; Controlled Series Compensator; Dynamic Power Flow Controller; Frequency Scanning; Phase-Shifting Transformer; Power Controller Plane; Power Flow Control; Power Oscillation Damping; Subsynchronous Resonance; Thyristor Controlled Series Compensator; Thyristor Switched Series Compensator; Transient Stability; Electrical engineering; Elektroteknik;

    Abstract : This thesis studies different aspects of Flexible AC Transmission System (FACTS) devices which are used to improve the power transfer capability and increase the controllability in electric power systems. In the thesis, different aspects on the usage and control of Dynamic Power Flow Controllers (DPFC) and related FACTS devices are studied. READ MORE