Sökning: "wind vector"

Visar resultat 1 - 5 av 17 avhandlingar innehållade orden wind vector.

  1. 1. Retrieval of Wind Velocity Vectors Over the Ocean Surface with Spaceborne Synthetic Aperture Radar

    Författare :Gisela Carvajal; Chalmers tekniska högskola; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; NATURVETENSKAP; NATURAL SCIENCES; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; wind vector; wind direction; synthetic aperture radar SAR ; CMOD-IFR2; local gradient.; ocean winds; wind speed;

    Sammanfattning : Wind over the ocean (normally defined at 10 meter height) is one of the main parameters affectingsea state, generating waves and driving currents. Wind field maps with large area coverageand high resolution therefore represent valuable information for a wide range of applications such asinformation for shipping, which carries 80% of the world’s trade, oil platforms and other maritime infrastructures,modeling, analysis and validation of weather models, improving performance of sensorsonboard maritime infrastructures, etc. LÄS MER

  2. 2. System Aspects and Modulation Strategies of an HVDC-based Converter System for Wind Farms

    Författare :Stephan Meier; Hans-Peter Nee; Boon-Teck Ooi; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Isolated AC DC Converter; Mutual Commutation; Soft Switching; Voltage Source Converter; Cycloconverter; Modulation Strategies; Medium-Frequency Transformer; HVDC Transmission; Wind Power; Wind Farms; Electric power engineering; Elkraftteknik; Electrical engineering; Elektroteknik;

    Sammanfattning :   In this thesis, a new HVDC-based converter system for wind farms is investigated. It is based on a mutually commutated soft-switching converter system and provides a unique integrated solution for the wind turbine generator drive systems, the wind turbine interconnection, and the power conversion for HVDC transmission. LÄS MER

  3. 3. Analysis and Control Aspects of Brushless Induction Machines with Rotating Power Electronic Converters

    Författare :Naveed ur Rehman Malik; Chandur Sadarangani; Luca Peretti; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Doubly-fed induction generator; extended vector control; induction machine; internal model control; Lindmark concept; low voltage ride through; passive resistive network; rotating power electronic converter; rotating exciter; symmetrical faults; synchronous machine; unity power factor; unsymmetrical faults; vector control; wind turbines.; Järnvägsgruppen - Elsystem; Järnvägsgruppen - Elsystem;

    Sammanfattning : This thesis deals with the steady-state, dynamic and control aspects of new type of brushless configuration of a doubly-fed induction machine in which the slip rings and carbon brushes are replaced by rotating power electronics and a rotating exciter. The aim is to study the stability of this novel configuration of the generator under mechanical and grid disturbances for wind power applications. LÄS MER

  4. 4. Modelling, Analysis, and Control Aspects of a Rotating Power Electronic Brushless Doubly-Fed Induction Generator

    Författare :Naveed ur Rehman Malik; Chandur Sadarangani; Torbjörn Thiringer; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Brushless doubly-fed induction generator; dual vector control; dynamic model; induction machine; internal model control; Lindmark concept; low-voltage ride-through; passive resistive network; rotating power electronic converter; rotating exciter; symmetrical faults; synchronous machine; thermal model; unity power factor; unsymmetrical faults; vector control; wind turbines.; Electrical Engineering; Elektro- och systemteknik; Energy Technology; Energiteknik;

    Sammanfattning : This thesis deals with the modeling, analysis and control of a novel brushlessgenerator for wind power application. The generator is named as rotatingpower electronic brushless doubly-fed induction machine/generator (RPEBDFIM/G).A great advantage of the RPE-BDFIG is that the slip power recoveryis realized in a brushless manner. LÄS MER

  5. 5. Grid-Connected Voltage Source Converter - Control Principles and Wind Energy Applications

    Författare :Jan Svensson; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; wind turbine; voltage source converter; voltage angle control; frequency response; vector current control; grid-connected; forced-commutated; measurements;

    Sammanfattning : The thesis focuses on a forced-commutated voltage source converter (VSC) connected to a grid in a wind energy application. The work consists of four parts. The first part addresses the type of electrical system which should be used in a wind turbine. LÄS MER