Estimação de Fasores para Proteção de Sistemas Elétricos Baseada em Mínimos Quadrados e Morfologia Matemática

This work proposes a new technique for phasor estimation applied in microprocessor numerical relays for distance protection of transmission lines, based on the recursive least squares method and called least squares modified random walking. The phasor estimation methods have compromised their performance, mainly due to the DC exponential decaying component present in fault currents. In order to reduce the influence of the DC component, a Morphological Filter (FM) was added to the method of least squares and previously applied to the process of phasor estimation. The presented method is implemented in MATLABr and its performance is compared to one-cycle Fourier technique and conventional phasor estimation, which was also based on least squares algorithm. The methods based on least squares technique used for comparison with the proposed method were: forgetting factor recursive, covariance resetting and random walking. The techniques performance analysis were carried out by means of signals synthetic and signals provided of simulations on the Alternative Transient Program (ATP). When compared to other phasor estimation methods, the proposed method showed satisfactory results, when it comes to the estimation speed, the steady state oscillation and the overshoot. Then, the presented method performance was analyzed by means of variations in the fault parameters (resistance, distance, angle of incidence and type of fault). Through this study, the results did not showed significant variations in method performance. Besides, the apparent impedance trajectory and estimated distance of the fault were analysed, and the presented method showed better results in comparison to one-cycle Fourier algorithm

El Istmo Centroamericano durante el período 1990-2002: los efectos de la volatilidad del crecimiento en el empleo, los salarios reales, el gasto público social, la pobreza y la distribución del ingreso

Incluye Bibliografía

Consecuencias iniciales de los comportamientos PYMEs en el nuevo escenario de negocios en Argentina

Incluye Bibliografía

Precios, salarios y empleo en la Argentina: estadísticas económicas de corto plazo

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Salarios y empleo en coyunturas recesivas internacionales: experiencias latinoamericanas recientes

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La rigidez de los salarios en Chile

Incluye Bibliografía

El régimen de salarios y su influencia en la selección de la mano de obra rural: estudio de algunas comunas rurales de la periferia de la ciudad de Santiago = Wage structure and its influence on the selection of rural labour: survey of a number of rural communes in the Santiago areas

Los documentos del Seminario fueron publicados por UNESCO en 1961 con el título: La urbanización en América Latina/Urbanization in Latin America

Método dos mínimos quadrados com penalidades: aplicação no posicionamento relativo GPS

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Simulação numérica de escoamentos de fluidos pelo método de elementos finitos de mínimos quadrados

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Estudo acústico da pronúncia de pares mínimos vocálicos do inglês por falantes nativos, professores brasileiros e alunos de nível intermediário e avançado

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

A arquitetura da criação: um estudo de Mínimos, múltiplos, comuns, de João Gilberto Noll

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Determinação de órbitas com o GPS através de mínimos quadrados recursivo com rotações de Givens

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)