Search for dissertations about: "HVDC converters"

Showing result 21 - 25 of 38 swedish dissertations containing the words HVDC converters.

2. 21. On Stability Enhancement in AC/DC Power Systems through Multi-terminal HVDC Controllers

   Author : Omar Kotb; Mehrdad Ghandari; Oriol Gomis Bellmunt; KTH; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; AC DC power system; hybrid MTDC; multi-terminal HVDC; small signal stability; VSC-MTDC; Electrical Engineering; Elektro- och systemteknik;

   Abstract : Due to the increasing share of renewable energy sources in modern power systems and electricity market deregulation, heavy inter-regional and cross-border power flows are becoming a commonplace in system operation. Moreover, large-scale integration of renewable energy sources is expected to pace up, therefore new solutions have to be developed to integrate these intermittent sources, which are also characterized by being distributed over large geographical areas, such as offshore wind farms. READ MORE

4. 22. Energy-efficient Generating System for HVDC Off-shore Wind Turbine

   Author : Poopak Roshanfekr; Chalmers tekniska högskola; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; surface permanent magnet synchronous generator SPMSG ; IGBT active rectifier; high voltage direct current HVDC ; wind energy; dc-link voltage; synchronous reluctance generator SynRG ; annual energy efficiency; diode passive rectifier; finite element method FEM ; interior permanent magnet synchronous generator IPMSG ;

   Abstract : This thesis investigates the design of energy efficient generating systems for off-shore wind turbines. For the generator part of the electric drive system, a surface mounted permanent magnet synchronous generator (SPMSG), an interior permanent magnet generator (IPMSG) as well as a synchronous reluctance generator (SynRG) have been investigated. READ MORE

5. 23. Modelling and control of a line-commutated HVDC transmission system interacting with a VSC STATCOM

   Author : Paulo Fischer de Toledo; Hans-Peter Nee; Gustaf Ohlsson; KTH; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Keywords : HVDC transmission; LCC – Line-commutated Current-source Converter; STATCOM; VSC – Voltage Source Converter; Space-Vector complex vector ; transfer-function; frequency-domain analysis; Electrical engineering; electronics and photonics; Elektroteknik; elektronik och fotonik;

   Abstract : The interaction of an HVDC converter with the connected power system is of complex nature. An accurate model of the converter is required to study these interactions. The use of analytical small-signal converter models provides useful insight and understanding of the interaction of the HVDC system and the connected system components. READ MORE

6. 24. Grid connection of offshore renewable energy sources

   Author : Christoffer Fjellstedt; Karin Thomas; Mats Leijon; Daniel Månsson; Uppsala universitet; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Grid connection; Electronic filters; Power transformers; Offshore collection grids; HVDC transmission; HVAC transmission; Marine current energy; Engineering Science with specialization in Science of Electricity; Teknisk fysik med inriktning mot elektricitetslära;

   Abstract : In order to achieve net zero emissions from the electricity sector, the proportion of renewable energy sources connected to the electrical grid needs to be increased significantly in the coming years. Established renewable energy sources, such as wind power and solar power, will certainly be crucial in achieving this. READ MORE

7. 25. Coordination of protection system and VSC-HVDC to mitigate cascading failures

   Author : Rujiroj Leelaruji; Lennart Söder; Jianping Wang; KTH; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Electric power engineering; Elkraftteknik;

   Abstract : The rapid development of the global economics has made power systems allover the world become large-scale interconnected grids. This increases the capabilityof power grids to transfer power over the long distance to serve the desiredpower demand with the minimum cost of operation. READ MORE