Search for dissertations about: "Electric power system"

Showing result 21 - 25 of 425 swedish dissertations containing the words Electric power system.

2. 21. Flywheel in an all-electric propulsion system

   Author : Johan Lundin; Hans Bernhoff; P-O Västeräng; Uppsala universitet; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Flywheel; electric vehicle; hybrid vehicle; power management; energy storage;

   Abstract : Energy storage is a crucial condition for both transportation purposes and for the use of electricity. Flywheels can be used as actual energy storage but also as power handling device. Their high power capacity compared to other means of storing electric energy makes them very convenient for smoothing power transients. READ MORE

4. 22. Differential Protection for Arbitrary Three-Phase Power Transformers

   Author : Zoran Gajic; Industriell elektroteknik och automation; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; electric power systems; power transformers; differential protection; power system protection;

   Abstract : This thesis describes how to provide standardized, current based, differential protection for any three-phase power transformer, including phase-shifting transformers with variable phase angle shift and transformers of all construction types and internal on-load tap-changer configurations. The use of standard transformer differential protection for such applications is considered impossible in the protective relaying standards and practices currently applied. READ MORE

5. 23. 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

6. 24. Modeling of Wind Turbines for Power System Studies

   Author : Tomas Petru; Chalmers tekniska högskola; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; flicker; fault response; power quality; wind turbine; power system stability; measurements; prediction; verification; grid simulation; modeling;

   Abstract : The power quality impact of wind turbines on the electric grid and the response of the wind turbines to faults in the electric grid are investigated in this thesis. A detailed model of a stall-regulated, fixed-speed wind turbine system capable of predicting the flicker impact on the connected grid is presented and compared with field measurements. READ MORE

7. 25. Some Control Applications in Electric Power Systems

   Author : Magnus Akke; Industriell elektroteknik och automation; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; load switching.; power oscillations; differential equation algorithm; transmission line protection; computer relaying; frequency estimation; DC cable; magnetic compass; Automation; robotics; control engineering; Automatiska system; robotteknik; reglerteknik;

   Abstract : This thesis presents some control applications in electric power systems. The work consists of the four parts: interaction between DC cables and ship steering autopilots; frequency estimation; computer relaying; field tests using load switching to damp power oscillations. READ MORE