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1. 1. Efficient Solid-State Power Amplifiers for RF Power Source Applications

   Författare :Renbin Tong; Dragos Dancila; Jörgen Olsson; Olof Bengtsson; Zoya Popovic; Uppsala universitet; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; back-off efficiency; high efficiency; power source; RF energy; RF measurements; radioisotope production; solid-state power amplifiers; Engineering Science with specialization in Microwave Technology; Teknisk fysik med inriktning mot mikrovågsteknik;

   Sammanfattning : Radio Frequency (RF) power sources are extensively applied in various fields. Radioisotope production, i.e., the production of short-lived radioactive isotopes, for positron emission tomography (PET) is one of the most important applications in the medical and healthcare domains. LÄS MER

3. 2. Modeling, Control and Protection of Low-Voltage DC Microgrids

   Författare :Daniel Salomonsson; Lennart Söder; Brian K. Johnsson; KTH; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; circuit transient analysis; dc power systems; dispersed storage and generation; load modeling; power conversion; power distribution control; power distribution faults; power distribution protection; power electronics; Electric power engineering; Elkraftteknik;

   Sammanfattning : Current trends in electric power consumption indicate an increasing use of dc in end-user equipment, such as computers and other electronic appliances used in households and offices. With a dc power system, ac/dc conversion within these loads can be avoided, and losses reduced. LÄS MER

4. 3. Power System Operation Planning and Wind Power Curtailment : Efficient Methods for Power System Scheduling and Integration Studies of Variable Renewable Energy

   Författare :Elis Nycander; Lennart Söder; Mehrdad Ghandari; Robert Eriksson; Germán Morales-España; Benjamin Hobbs; KTH; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Variable renewable energy; wind power integration; production cost model; power-based unit commitment; wind power scenarios; Electrical Engineering; Elektro- och systemteknik;

   Sammanfattning : To reduce carbon dioxide emissions, variable renewable energy (VRE) sources are replacing conventional fossil-based power plants for electricity generation. Due to the variability and uncertainty of weather dependent VRE sources, there can be situations when it is not possible to accommodate all the available VRE production, and VRE sources have to be curtailed. LÄS MER

5. 4. Power Electronics for Mitigation of Voltage Sags and Improved Control of AC Power Systems

   Författare :Marcio Magalhães de Oliveira; KTH; []
   Nyckelord :power electronics; power quality; voltage sags; voltage-source converters; Custom Power; FACTS; real-time simulations; solid-state devices;

   Sammanfattning : The thesis deals with the application of compensators andswitches based on power electronics in AC transmission anddistribution systems. The objective of the studieddevices/equipment is the power flow and voltage control intransmission systems and the mitigation of voltage sags andmomentary interruptions to critical loads in distributionsystems. LÄS MER

7. 5. On optimal hydropower bidding in systems with wind power : Modeling the impact of wind power on power markets

   Författare :Magnus Olsson; Lennart Söder; Stein-Erik Fleten; KTH; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Hydropower; wind power; stochastic modeling; optimization; Electric power engineering; Elkraftteknik;

   Sammanfattning : The introduction of large amounts of wind power into power systems will increase the production uncertainties due to unforeseen wind power production variations. This will have a significant impact on the required balance management quantities. LÄS MER