Please cite only the published version using the reference above.See http://opus.bath.ac.uk/ for usage policies.Please scroll down to view the document. Abstract In this paper, a 220-V resistive superconducting fault current limiter (SFCL) prototype is built and tested under different prospective fault currents, which vary from 0.8 to 7.4 kA. A 2D superconductor model is integrated into an experimental circuit model in COMSOL to simulate the performance of the SFCL prototype in the experimental system in fault tests. In the simulation, a new E-J relationship is proposed to enhance the convergence of calculation.Comparison between simulation results and experimental results shows that the proposed model performs well in simulating current limiting performance of SFCL in experimental system in case of fault.

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AGRADECIMENTOSAos meus pais Carlos Javier Lamas e Maria Rossana Samanamud Lamas por todo o investimento que fizeram em mim de tal forma a possibilitar melhores condições de estudo e oportunidades. Pelo suporte prestado durante este tempo e pelas palavras de sabedoria nos momentos oportunos. Aos meus irmãos Gisella Rossana Lamas Samanamud e Mario Javier Lamas pelo apoio, conselhos e companhia. Aos meus cachorros Karpet e Dolly que me acompanharam no início dos meus trabalhos e não puderam ver a finalização do mesmo e Panda e Shanti cuja companhia me alegram e cujos passeios diários me fazem achar soluções para problemas. Ao meu namorado Henk Huisseune pela paciência e apoio nos dias mais difíceis e pelos conselhos e dicas quando tive dúvidas. Ao Prof. Dr. Carlos Alberto Baldan por acreditar que eu poderia realizar este trabalho e por me orientar pessoalmente, por telefone e por e-mail. Ao Prof. Dr. Carlos Yujiro Shigue pela contribuição profissional e científica, pessoal e orientação durante este trabalho. A Profa. Dra. Cristina Bormio pelas instruções e informações fornecidas. Ao Prof. Dr. Victo Moshalkov por permitir a realização das medidas magnéticas em seu laboratório INPAC -KULeuven. Ao PhD Alejandro Silhanek da KULeuven pelo auxílio nas medidas magnéticas. Aos amigos de pós-graduação e graduação pela amizade, colaborações e compartilhamento de idéias. Aos amigos que participaram de minha formação pessoal, Aos funcionários e técnicos, Bento, Sávio, Dainesi, Geraldo Prado, Brás e todos os demais, que sempre foram prestativos em todas as necessidades ao longo do trabalho. Ao Departamento de Engenharia de Materiais da Escola de Engenharia de Lorena por colocar a disposição a área experimental para realização deste trabalho.A CAPES e CPFL pelo apoio financeiro para a realização deste trabalho de mestrado. Palavras-chave: Limitadores de corrente supercondutores resistivos (FCL). Fitas HTS. Fitas BSCCO. Fitas YBCO. Caracterização de fitas. ABSTRACT LAMAS, J.S. Project and construction of a fault current limiter using YBCO tapes. Resistive Superconducting fault current limiter (SFCL) are devices with electrical behavior near the ideal when it changes its state from the superconducting to the normal state, limiting the fault current by the insertion of a fast transition resistance in the grid. The technical and economical feasibility of these limiters arose after the development of the high critical temperature superconductors HTS. First generation HTS tapes (BSCCO) consist of multifilamentary composite tapes embedded in a silver matrix. The typical critical current density is approximately 14 kA/cm 2 . However, the resistance reached by the SFCL when normal state occurs is not high enough to limit the fault current, making necessary long lengths of tapes (~5 km) for limiting purposes. The recently development of coated conductors composites with high resistivity metal substrate have succeeded the BSCCO tapes which are based on YBCO textured film. Upon carrying a critical current density of 13.6 kA/cm 2 , YBCO tapes...

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The evaluation of the electrical characteristics of technical HTS tapes are of the key importance in determining the design and operational features of superconducting power apparatuses as well as to understand the external factors which affect the superconducting performance. In this work we report the systematic measurements of the electric field versus current density, relation of short samples for three commercial HTS tapes (BSCCO-2223 tapes, with and without steel reinforcement, and YBCO-coated conductor) at 77 K. In order to get sensitive and noiseless voltage signals the measurements were carried out with DC transport current and subjecting the broad surface tape to DC (0-300 mT) and AC (0-62 mT, 60 Hz) magnetic fields. The voltage is measured by a sensitive nanovoltmeter and the applied magnetic field is monitored by a Hall sensor placed on the tape broad surface. The comparison between the results obtained from the three tapes was done by fitting a power-law equation for currents in the vicinity of the critical current. For the current regime below the critical one a linear correlation of the electric field against the current density is observed. The BSCCO samples presented the same behavior, i.e., a decreasing of -index with the increasing DC and AC magnetic field strength. Under AC field the decreasing slope of -index is steeper as compared to DC field. The -index curve for the YBCO tape showed similar behavior for AC field, however under DC field in the 0-390 mT range exhibited a slight decreasing of the -index.