Search for dissertations about: "symmetrical faults"

Showing result 1 - 5 of 6 swedish dissertations containing the words symmetrical faults.

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

   Author : Naveed ur Rehman Malik; Chandur Sadarangani; Torbjörn Thiringer; KTH; []
   Keywords : 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;

   Abstract : 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. READ MORE

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

   Author : Naveed ur Rehman Malik; Chandur Sadarangani; Luca Peretti; KTH; []
   Keywords : 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;

   Abstract : 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. READ MORE

5. 3. Fault Behavior of Wind Turbines

   Author : Francesco Sulla; Industriell elektroteknik och automation; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Wind Turbines; Short-Circuit Currents; Doubly-Fed Induction Generator; Grid Fault Ride-Through; Voltage Support; Weak Grid;

   Abstract : Synchronous generators have always been the dominant generation type in the grid. This fact affected both planning and operation of power systems. With the fast increase of wind power share in the grid in the last decade, the situation is changing. In some countries wind power represents already a consistent amount of the total generation. READ MORE

6. 4. 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

7. 5. Aspects on Wind Turbine Protections and Induction Machine Fault Current Prediction

   Author : Marcus Helmer; Chalmers tekniska högskola; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; saturation; Induction generator; Short circuit currents; Slip ring Generator; skin effect;

   Abstract : This thesis presents detailed modelling of the induction machine with the main objective being accurate fault current prediction. The thesis focus mainly on mains connected induction machines and the response due to severe disturbances in the supply voltage, such as three-phase short-circuit faults. READ MORE