Sökning: "Power transformer"

Visar resultat 6 - 10 av 78 avhandlingar innehållade orden Power transformer.

1. 6. Wind-turbine harmonic emissions and propagation through a wind farm

   Författare :Kai Yang; Åke Larsson; Luleå tekniska universitet; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Renewable energy; Electric power system; Wind power; Power quality; Power system harmonics; Electric Power Engineering; Elkraftteknik; Energy Engineering; Energiteknik;

   Sammanfattning : The increasing demand for sustainable energy is one of the driving forces behind the increasing use of wind power by means of wind-turbines in electric power systems. Modern wind turbines commonly employ variable-speed-generator technology associated with a power-electronic converter as part of the grid connection. LÄS MER

3. 7. Grid Connection of Permanent Magnet Generator Based Renewable Energy Systems

   Författare :Senad Apelfröjd; Sandra Eriksson; Frans Dijkhuizen; Uppsala universitet; []
   Nyckelord :VAWT; H-rotor; Tap Transformer; Cascaded H-bridge Multi-Level; Renewable Energy; Wind power; Wave power; Marine Current Power; Engineering Science with specialization in Science of Electricity; Teknisk fysik med inriktning mot elektricitetslära;

   Sammanfattning : Renewable energy is harnessed from continuously replenishing natural processes. Some commonly known are sunlight, water, wind, tides, geothermal heat and various forms of biomass. The focus on renewable energy has over the past few decades intensified greatly. LÄS MER

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

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

   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

5. 9. Dynamic Rating of Power Lines and Transformers for Wind Energy Integration

   Författare :Kateryna Morozovska; Patrik Hilber; Rajeev Thottappillil; Rebei Bel Fdhila; KTH; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; dynamic line rating; dynamic transformer rating; power transformers; heat balance; thermal modeling; wind power; wind energy integration; reliability analysis; risk analysis; Electrical Engineering; Elektro- och systemteknik;

   Sammanfattning : Dynamic Rating (DR) is usually associated with unlocking the capacity of power lines and transformers using available information on weather conditions. Our studies show that Dynamic Rating is a broad concept that requires further study and development. LÄS MER

7. 10. Temperature and heat losses simulation in core and winding of a power transformer

   Författare :Kourosh Mousavi Takami; Mahmoudi Jafar; Lennart Harnefors; Mälardalens högskola; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Electric Power Transformer; Losses; Simulation; Temperature; Calculation; Electric power engineering; Elkraftteknik; elektronik; Electronics;

   Sammanfattning : Simulering av temperatur och värmeförluster i kärna och lindning för en högspänningstransformator “... Ett ljus som lyser dubbelt så starkt, varar hälften så länge …”, i analogi med ljuset så kan transformatorer köras med överlast inom vissa gränser, men med följden att livslängden blir kortare. LÄS MER