Search for dissertations about: "thyristors"

Showing result 1 - 5 of 6 swedish dissertations containing the word thyristors.

2. 1. Hybrid Converters for HVDC Transmission

   Author : Panagiotis Bakas; Lennart Harnefors; Staffan Norrga; Hans-Peter Nee; Stephen Finney; KTH; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; High-voltage direct current HVDC ; hybrid alternate-common arm converter HACC ; hybrid converters; line-commutated converters LCCs ; modular multilevel converters MMCs ; thyristors; Hybrid alternate-common-arm converter HACC ; hybrid omvandlare; högspänd likströmsöverföring HVDC ; linjekommuterade omvandlare LCC ; modulära multinivåomvandlare MMC ; tyristorer; Electrical Engineering; Elektro- och systemteknik;

   Abstract : The line-commutated converter (LCC) and the voltage-source converter (VSC) are the two main converter technologies utilized in high-voltage direct current (HVDC) transmission applications. Depending on the application requirements, one technology might be more advantageous than the other. READ MORE

4. 2. Cascaded Converters with Gate-Commutated Thyristors : Experimental Verification and Auxiliary Power Supply

   Author : Tomas Modeer; Hans-Peter Nee; Staffan Norrga; Dragan Jovcic; KTH; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY;

   Abstract : This thesis describes an effort to investigate the use of gate-commutated thyristors(GCTs) in cascaded converters. Cascaded converters, such as modularmultilevel converters (M2Cs) and cascaded H-bridge converters (CHBs), haveproved to be especially suitable in high-voltage, high-power applications. READ MORE

5. 3. Cost-effective Cells for High-power Modular Multilevel Converters

   Author : Matthijs Heuvelmans; Staffan Norrga; Hans-Peter Nee; Rik De Doncker; KTH; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; MMC; modular multilevel converter; ARCP; IGCT; soft-switching; ZVS; ZCS; snubber; thyristor; SCR; silicon controlled rectifier; HVDC; STATCOM; Electrical Engineering; Elektro- och systemteknik;

   Abstract : The modular multilevel converter (MMC) topology was introduced in 2003and has since been receiving considerable attention from industry and academia.Notable benefits compared to two- or three-level voltage source convertersare its scalability, low switching losses, low output filter requirementsand ease of adding redundancy combined with fail-safe operation. READ MORE

6. 4. Dynamic Analysis of Harmonics in Electrical Systems

   Author : Erik Möllerstedt; Institutionen för reglerteknik; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Automation; converter control; modeling; linear time periodic systems; frequency domain analysis; harmonics; power systems; small signal stability; robotics; control engineering; Automatiska system; robotteknik; reglerteknik;

   Abstract : Frequency domain analysis and design of power systems is complicated in the presence of harmonics, switching dynamics, nonlinearities, unbalances, and for systems with mixed ac/dc dynamics. The reason is that linearization of the system does not lead to a time invariant system, but a system with periodically time varying dynamics, which implies that there is coupling between different frequencies. READ MORE

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

   Author : Stephan Meier; Hans-Peter Nee; Boon-Teck Ooi; KTH; []
   Keywords : 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;

   Abstract :   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. READ MORE