Search for dissertations about: "Power system controls"

Showing result 1 - 5 of 49 swedish dissertations containing the words Power system controls.

  1. 1. Optimal Railroad Power Supply System Operation and Design : Detailed system studies, and aggregated investment models

    Author : Lars Abrahamsson; Lennart Söder; Arnd Stephan; KTH; []

    Abstract : Railway power supply systems (RPSSs) differ mainly from public power systems from that the loads are moving. These moving loads are motoring trains. Trains can also be regenerating when braking and are then power sources. These loads consume comparatively much power, causing substantial voltage drops, not rarely so big that the loads are reduced. READ MORE

  2. 2. Coordinated Voltage Control in Electric Power Systems

    Author : Mats Larsson; Lunds universitet; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Electronics and Electrical technology; trees.; search methods; control; predictive; voltage control; power system dynamic stability; Modelica; ObjectStab; multi-machine power system; voltage stability; object oriented methods; modelling; simulation; describing function analysis; tap changer; limit cycle; Elektronik och elektroteknik; Electrical engineering; Elektroteknik;

    Abstract : This thesis deals with various aspects of coordinated voltage control in electric power systems. It consists of an introduction and six papers. The introduction contains a summary of the thesis and tutorials on voltage control and the search methods that have been applied. READ MORE

  3. 3. The emotional motor system and gastrointestinal symptoms

    Author : Pontus Karling; Lars Agréus; Umeå universitet; []
    Keywords : MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; Anxiety; ANS; autonomic nervous system; cortisol; DST; emotional motor system; functional; gastrointestinal symptoms; GSRS-IBS; gut; HADS; heart rate variability; HPA axis; IBS; irritable bowel syndrome; stress; unipolar depression; val158met COMT polymorphism; Gastroenterology; Gastroenterologi;

    Abstract : There is a significant comorbidity between anxiety/depression and functional gastrointestinal syndromes, such as irritable bowel syndrome (IBS) and functional dyspepsia. The pathophysiological link between emotions and the gut is not known. READ MORE

  4. 4. Evaluation and variability of power grid hosting capacity for electric vehicles : Case studies of residential areas in Sweden

    Author : Maria Sandström; Erik Dotzauer; Chris Bales; Pei Huang; Björn Laumert; Högskolan i Gävle; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Hosting capacity HC ; Power grid; Electric vehicle EV ; Charging strategies; Power flow simulations; Uncertainty analysis; Hållbar stadsutveckling; Sustainable Urban Development; inget Strategiskt forskningsområde SFO ; no Strategic Research Area SFO ;

    Abstract : Electric vehicles (EVs) are increasing in popularity and play an important role in decarbonizing the transport sector. However, a growing EV fleet can cause problems for power grids as the grids are not initially designed for EV charging. The potential of a power grid to accommodate EV loads can be assessed through hosting capacity (HC) analysis. READ MORE

  5. 5. Security of Time Synchronization for PMU-based Power System State Estimation: Vulnerabilities and Countermeasures

    Author : Ezzeldin Shereen; György Dán; Joe H. Chow; KTH; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Phasor measurements unit; Time synchronization; Power system state estimation; Network Security; Time synchronization attacks; Precision time protocol; Machine learning; Electrical Engineering; Elektro- och systemteknik;

    Abstract : Phasor Measurement Units (PMUs) constitute an emerging technology that is essential for various smart grid applications such as phase angle monitoring, power oscillation damping, fault localization, and linear state estimation. To obtain precise PMU measurements of voltage and current phasors, time synchronization in the order of 1 microsecond is typically required. READ MORE