Sökning: "electric power system"
Visar resultat 21 - 25 av 431 avhandlingar innehållade orden electric power system.
21. Flywheel in an all-electric propulsion system
Sammanfattning : 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. LÄS MER
22. Differential Protection for Arbitrary Three-Phase Power Transformers
Sammanfattning : 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. LÄS MER
23. Coordinated Voltage Control in Electric Power Systems
Sammanfattning : 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. LÄS MER
24. Modeling of Wind Turbines for Power System Studies
Sammanfattning : 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. LÄS MER
25. Some Control Applications in Electric Power Systems
Sammanfattning : 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. LÄS MER