Th. doct.-ing.--Génie électrique--Toulouse--I.N.P., 1982. N°: 205.

The work detailed in the thesis compares the performance of single-phase thyristor bridge converters under different control strategies; considering in particular the efficiency, ac side power factor and harmonic content of the current and voltage waveforms. Extensive practical investigations were performed, in which, analogue and digital control circuits were developed to provide the drive signals necessary for a converter to operate in the different control modes for: a) A series -connected fully-controlled double thyristor bridge (used mainly in traction applications) operating under sequence control and; b) A fully controlled single-bridge operating under sequence and conventional control. A novel pulse-width modulation control strategy was developed for the single-bridge converter, using gate turn-off thyristors as the switching elements, whereby output voltage control is obtained by variation of the modulation index. Turn-on and turn-off signals for the power devices were obtained using an analogue control circuit. The advantages and disadvantages of this switching strategy compared with conventional and sequence control were studied, and results clearly showed that an improved input power factor and lower supply current and load voltage harmonics were all obtained. Mathematical models for single and double bridge converters operating under sequence and conventional control were developed using tensor techniques. Using these models, computer programmes were written in Fortran 77 on the University mainframe computer, to assemble automatically and solve the network equations as the converter topology changes. In addition, analytical models were also developed on the assumption that the load current is completely smooth. However, such an assumption is not justifiable with ac-to-dc converters and consequently a novel technique was developed to include the load current ripple in calculating the supply current harmonics. The results obtained are compared with both the computed and experimental ones.

Thèse de doctorat : SCIENCES ET TECHNIQUES : Metz : 1999. / 1999METZ030S. 60 ref.

Thèse doctorat : Dispositifs de l'Electronique Intégrée : Villeurbanne, INSA : 2004. / Titre provenant de l'écran-titre. Bibliogr. p. 157-166.

Thesis--M. Phil., University of Hong Kong, 1979. / Photocopy of typewritten.

published_or_final_version / Electrical Engineering / Master / Master of Philosophy

Thesis (M.S. in Applied Physics)--Naval Postgraduate School, December 2008. / Thesis Advisor(s): Karunasiri, Gamani ; Tummala, Murali. "December 2008." Description based on title screen as viewed on January 29, 2009. Includes bibliographical references (p. 69-71). Also available in print.

University of Macau / Faculty of Science and Technology / Department of Electrical and Computer Engineering

Thesis (M.S.)--Texas State University--San Marcos, 2009. / Vita. Includes bibliographical references (leaf 56). Also available on microfilm.

Orientador: Jacobus Willibrordus Swart / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Eletrica e de Computação / Made available in DSpace on 2018-08-06T23:47:41Z (GMT). No. of bitstreams: 1 Orio_RobertoLacerdade_M.pdf: 1305384 bytes, checksum: e0e89b803f3ba5496d25f456a5f047dd (MD5) Previous issue date: 2006 / Resumo: Este trabalho tem como objetivo o projeto de um dispositivo supressor de surto de tensão para aplicação na proteção de equipamentos de telecomunicações. O projeto foi realizado com a utilização de programas de simulação. Os diversos parâmetros físicos, como dopagens e dimensões, assim como estruturas com e sem emitter-shorts foram estudadas para o entendimento da sua influência na operação do dispositivo supressor e estabelecer em que condições o seu melhor desempenho é obtido. Com base nos resultados adquiridos foi desenvolvido um processo de fabricação suficientemente simples para se aplicar em linha de produção. O dispositivo final proposto apresentou uma tensão de breakover de 250 V quando submetido a um pulso de corrente de 100 Alcm2. Após o chaveamento, a distribuição mais uniforme da densidade de corrente foi observada para uma estrutura com emitter-shorts não-centralizados em relação à área dos emissores do dispositivo / Abstract: This work intends to design a voltage surge suppressor device for telecommunications equipments. The project was conducted with the help of simulation tools. The physical parameters like dopings and dimensions, as well as structures with and without emitter­ shorts were studied in order to understand their influence on the device behavior and to establish in which conditions its best performance is obtained. Based on these simulation results, a simple fabrication process for line production was developed. The final device presented a breakover voltage of 250 V when a current pulse of 100 Alcm2 was applied. After the device turn-on the most uniform distribution of current density was observed for a structure with emitter-shorts non-centralized on the emitter device area / Mestrado / Eletrônica, Microeletrônica e Optoeletrônica / Mestre em Engenharia Elétrica