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Pontifical Catholic University of Rio de Janeiro

1. JELITZA LUZ CEBALLOS INFANTES. [en] DETERMINATION OF VOLTAGE CONTROL AREAS BASED ON INTERDEPENDENT CONTROLLER EQUIPMENTS.

Degree: 2011, Pontifical Catholic University of Rio de Janeiro

[pt] Após a incidência de inúmeros problemas relacionados a fenômenos de instabilidade de tensão, o controle de potência reativa em sistemas elétricos de potência tornou-se um assunto importante os últimos anos. Um adequado controle do perfil de tensão em uma área pode contribuir para evitar este tipo de problema. Com esse objetivo, determinam-se áreas de controle de tensão a partir da análise dos autovalores e autovetores das matrizes de sensibilidade: VCS Voltage Control Sensitivity Matrix e QV. A matriz de sensibilidade [VCS] é constituída por elementos diagonais que relacionam a grandeza controladora de cada equipamento com a respectiva tensão controlada (variável controlada), e a análise do sinal desses elementos estabelece se uma determinada ação de controle será adequada ou não, isto é, se terá efeito esperado ou oposto. Os elementos fora da diagonal representam a interdependência existente entre os equipamentos controladores de tensão. A matriz de sensibilidade QV, nomeada como [JSQV] é obtida a partir da matriz Jacobiana do sistema linearizado das equações de fluxo de carga. As áreas de controle de tensão determinadas da análise por autovalores e autovetores usando-se cada uma das matrizes de sensibilidade são coerentes. Adicionalmente, obtêm-se áreas de controle de tensão diretamente das matrizes de sensibilidade. Estas áreas foram comparadas encontrando-se resultados coerentes.

[en] After of the incidence of innumerable problems related to voltage instability phenomena, the control of reactive power in electrical power systems became an important issue in the last years. The adequate control of the voltage for a specific area can prevent this kind of problem. With this objective, voltage control areas are established from an eigenvalues and eigenvectors analysis of the sensitivity matrixes: VCS Voltage Control Sensitivity Matrix and QV. The sensitive matrix [VCS] is form by diagonal elements that relate to the controlling variables and to the controlled voltage (controlled variable), and the analysis of the sign of each diagonal element indicate if a specific control action is adequate or not. The off-diagonal elements represent the interdependence among the voltage controller equipments. The sensitivity matrix QV, called [JSQV] is obtained from the Jacobean matrix from the linear load flow equations. The voltage control areas recognized from the eigenvalues and eigenvectors analysis to each sensitivity matrix are coherent. Also, voltage control areas were identified directly from sensitivity matrixes. These areas were compared founded coherent results.

Advisors/Committee Members: RICARDO BERNARDO PRADA.

Subjects/Keywords: [pt] CONTROLE DE TENSAO; [en] VOLTAGE CONTROL; [pt] AUTOVALORES; [en] EIGENVALUES; [pt] EQUIPAMENTOS; [en] EQUIPMENT

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6th Edition):

INFANTES, J. L. C. (2011). [en] DETERMINATION OF VOLTAGE CONTROL AREAS BASED ON INTERDEPENDENT CONTROLLER EQUIPMENTS. (Thesis). Pontifical Catholic University of Rio de Janeiro. Retrieved from http://www.maxwell.vrac.puc-rio.br/Busca_etds.php?strSecao=resultado&nrSeq=18287

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16th Edition):

INFANTES, JELITZA LUZ CEBALLOS. “[en] DETERMINATION OF VOLTAGE CONTROL AREAS BASED ON INTERDEPENDENT CONTROLLER EQUIPMENTS.” 2011. Thesis, Pontifical Catholic University of Rio de Janeiro. Accessed January 21, 2020. http://www.maxwell.vrac.puc-rio.br/Busca_etds.php?strSecao=resultado&nrSeq=18287.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7th Edition):

INFANTES, JELITZA LUZ CEBALLOS. “[en] DETERMINATION OF VOLTAGE CONTROL AREAS BASED ON INTERDEPENDENT CONTROLLER EQUIPMENTS.” 2011. Web. 21 Jan 2020.

Vancouver:

INFANTES JLC. [en] DETERMINATION OF VOLTAGE CONTROL AREAS BASED ON INTERDEPENDENT CONTROLLER EQUIPMENTS. [Internet] [Thesis]. Pontifical Catholic University of Rio de Janeiro; 2011. [cited 2020 Jan 21]. Available from: http://www.maxwell.vrac.puc-rio.br/Busca_etds.php?strSecao=resultado&nrSeq=18287.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

INFANTES JLC. [en] DETERMINATION OF VOLTAGE CONTROL AREAS BASED ON INTERDEPENDENT CONTROLLER EQUIPMENTS. [Thesis]. Pontifical Catholic University of Rio de Janeiro; 2011. Available from: http://www.maxwell.vrac.puc-rio.br/Busca_etds.php?strSecao=resultado&nrSeq=18287

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation


Pontifical Catholic University of Rio de Janeiro

2. JAVIER ORTEGA SOTOMAYOR. [en] INTERDEPENDENCE OF VOLTAGE CONTROL EQUIPMENTS: COHERENCY ASSESSMENT IN THE POWER FLOW PROBLEM.

Degree: 2012, Pontifical Catholic University of Rio de Janeiro

[pt] Com o aumento do número de dispositivos de controle representados nos casos práticos, pode ser verificado o aparecimento de interações entre suas ações de controle. Quando estas interações não são coordenadas podem ocasionar a diminuição da eficiência do método de Newton-Raphson no problema de fluxo de potência, resultando em convergências lentas e frequentemente soluções oscilatórias ou até mesmo a divergência do método. Uma adequada identificação destas interações pode contribuir para tomar as medidas corretivas necessárias e assim evitar este tipo de problema. Com esse objetivo, identificam-se as interações entre múltiplos dispositivos de controle (mais de dois equipamentos de controle) a partir da análise dos autovalores e fatores de participação da matriz de sensibilidade de controles denominada [MSC]. Esta matriz, elaborada com base num modelo alternativo para a representação do controle de tensão local das barras PV, é obtida da redução da matriz Jacobiana expandida do problema de fluxo de potência. Dentro deste contexto, se verifica a presença de autovalores que apresentam informações similares sobre os dispositivos de controle com fortes interações entre suas ações de controle, desenvolvendo-se assim, um método baseado no conceito de colinearidade capaz de identificar e agrupar estes autovalores. Os resultados da avaliação do método desenvolvido aplicado em sistemas de pequeno e grande porte mostram a relevância e a viabilidade da utilização prática dos desenvolvimentos propostos neste trabalho.

[en] The increasing number of control devices represented in practical cases, we can see the appearance of interactions between their control actions. When these interactions are not coordinated (conflict), the efficiency of Newton- Raphson method decrease to the power flow problem, the convergence is slow and the solutions are oscillatory. A correct identification of these interactions can help to take corrective actions and thus avoid this problem. With this objective, the identification of interactions between control devices (more than 2 control equipment) is established from the modal analysis of the sensitivity matrix [MSC]. This sensitivity matrix [MSC] is developed in based to alternative model to represent the local voltage control of the PV buses. This [MSC] is obtained from the reduction of the Jacobean matrix expanded of power flow problem. Within this context, it also checks for the presence of eigenvalues that have similar information about the significant interactions between control devices, thus developing a method based on the use index of sensitivity matrix [MSC] and concept of collinearity able to identify and group these eigenvalues. The results of the evaluation method applied to systems designed for small and large show the relevance and feasibility of practical use of proposed developments in this work.

Advisors/Committee Members: RICARDO BERNARDO PRADA.

Subjects/Keywords: [pt] CONTROLE DE TENSAO; [en] VOLTAGE CONTROL; [pt] AUTOVALORES; [en] EIGENVALUES; [pt] AREAS DE CONTROLE DE TENSAO

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6th Edition):

SOTOMAYOR, J. O. (2012). [en] INTERDEPENDENCE OF VOLTAGE CONTROL EQUIPMENTS: COHERENCY ASSESSMENT IN THE POWER FLOW PROBLEM. (Thesis). Pontifical Catholic University of Rio de Janeiro. Retrieved from http://www.maxwell.vrac.puc-rio.br/Busca_etds.php?strSecao=resultado&nrSeq=20273

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16th Edition):

SOTOMAYOR, JAVIER ORTEGA. “[en] INTERDEPENDENCE OF VOLTAGE CONTROL EQUIPMENTS: COHERENCY ASSESSMENT IN THE POWER FLOW PROBLEM.” 2012. Thesis, Pontifical Catholic University of Rio de Janeiro. Accessed January 21, 2020. http://www.maxwell.vrac.puc-rio.br/Busca_etds.php?strSecao=resultado&nrSeq=20273.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7th Edition):

SOTOMAYOR, JAVIER ORTEGA. “[en] INTERDEPENDENCE OF VOLTAGE CONTROL EQUIPMENTS: COHERENCY ASSESSMENT IN THE POWER FLOW PROBLEM.” 2012. Web. 21 Jan 2020.

Vancouver:

SOTOMAYOR JO. [en] INTERDEPENDENCE OF VOLTAGE CONTROL EQUIPMENTS: COHERENCY ASSESSMENT IN THE POWER FLOW PROBLEM. [Internet] [Thesis]. Pontifical Catholic University of Rio de Janeiro; 2012. [cited 2020 Jan 21]. Available from: http://www.maxwell.vrac.puc-rio.br/Busca_etds.php?strSecao=resultado&nrSeq=20273.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

SOTOMAYOR JO. [en] INTERDEPENDENCE OF VOLTAGE CONTROL EQUIPMENTS: COHERENCY ASSESSMENT IN THE POWER FLOW PROBLEM. [Thesis]. Pontifical Catholic University of Rio de Janeiro; 2012. Available from: http://www.maxwell.vrac.puc-rio.br/Busca_etds.php?strSecao=resultado&nrSeq=20273

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation


Pontifical Catholic University of Rio de Janeiro

3. ALEXANDRE ASHADE LASSANCE CUNHA. [en] ANALYTICAL SOLUTION OF EIGENVALUE EQUATIONS BY GENETIC PROGRAMMING, WITH APPLICATION IN THE ANALYSIS OF ELECTROMAGNETIC PROPAGATION IN PRODUCTION PIPES OF OIL, PARAMETERIZED BY THE RADIUS AND THE PERCENTAGE OF INCRUSTATIONS.

Degree: 2019, Pontifical Catholic University of Rio de Janeiro

[pt] Este trabalho apresenta uma abordagem inovadora para calcular autopares de operadores diferenciais (OD), utilizando programação genética (PG) e computação simbólica. Na literatura atual, o Método dos Elementos Finitos (MEF) e o Método das Diferenças Finitas (MDF) são os mais utilizados. Tais métodos usam discretização para converter o OD em uma matriz finita e, por isso, apresentam limitações como perda de acurácia e presença de soluções espúrias. Além disso, se o domínio do OD fosse alterado, os autopares precisariam ser calculados novamente, pois a representação matricial do operador depende dos parâmetros do problema. Nesse contexto, este trabalho propõe evoluir autofunções analiticamente usando PG, sem discretização do domínio. Com isso, é possível incorporar parâmetros, o que torna a solução obtida válida para uma classe de problemas. Este texto descreve o modelo para OD normais, aplicando conceitos de indivíduos multi-árvore e diferenciação simbólica. O modelo evolui auto-funções e, a partir delas, calcula os autovalores empregando a razão de Rayleigh. Experimentos baseados em aplicações da Física mostram que a técnica proposta é capaz de encontrar as autofunções analíticas com a acurácia igual ou melhor que as técnicas numéricas supracitadas. Finalmente, a técnica proposta é aplicada ao problema de propagação de ondas eletromagnéticas em poços de petróleo em ULF e UHF. As soluções analíticas são dadas em função do diâmetro e do percentual de incrustações no poço. Os resultados mostram que, para um conjunto suficientemente grande de valores distintos dos parâmetros, a técnica apresenta tempo de execução inferior às técnicas clássicas, mantendo a acurácia destas.

[en] This work presents an innovative approach to calculate the eigenpairs of linear differential operators (LDO), employing genetic programming (GP) and symbolic computation. In the current literature, the Finite Element Method (FEM) and the Finite Difference Method (FDM) are more commonly used. Such methods use discretization to convert the LDO to a finite matrix, therefore causing loss of accuracy and presence of spurious solutions. Additionally, if the domain of the LDO was changed, the eigenpairs would need to be recalculated, since the matrix representation of the LDO depends on the parameters of the problem. In this context, this work proposes to evolve eigenfunctions analytically using GP, without domain discretization. Hence, it is possible to incorporate the parameter, which makes a obtained solution valid for a class of problems. This text describes the model for normal LDO, applying concepts of multi-tree individuals and symbolic differentiation. The presented model evolves eigenfunctions and, then, calculates the eigenvalues using the Rayleigh quotient. Experiments based on Physics problems show that the proposed technique is able to find the analytical eigenfunctions with the same accuracy of the numerical techniques mentioned above. Finally, the proposed technique is applied to the problem of propagation of electromagnetic waves in oil…

Advisors/Committee Members: MARCO AURELIO CAVALCANTI PACHECO, MARCO AURELIO CAVALCANTI PACHECO.

Subjects/Keywords: [pt] AUTOVALORES; [en] EIGENVALUES; [pt] ELETROMAGNETISMO COMPUTACIONAL; [en] COMPUTATIONAL ELECTROMAGNETICS; [pt] OPERADORES DIFERENCIAIS LINEARES; [en] LINEAR DIFFERENTIAL OPERATORS; [pt] TELEMETRIA DE POCOS DE PETROLEO; [en] OIL WELL TELEMETRY; [pt] SOLUCAO ANALITICA PARAMETRICA; [en] PARAMETRIC AND ANALYTICAL SOLUTIONS

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6th Edition):

CUNHA, A. A. L. (2019). [en] ANALYTICAL SOLUTION OF EIGENVALUE EQUATIONS BY GENETIC PROGRAMMING, WITH APPLICATION IN THE ANALYSIS OF ELECTROMAGNETIC PROPAGATION IN PRODUCTION PIPES OF OIL, PARAMETERIZED BY THE RADIUS AND THE PERCENTAGE OF INCRUSTATIONS. (Thesis). Pontifical Catholic University of Rio de Janeiro. Retrieved from http://www.maxwell.vrac.puc-rio.br/Busca_etds.php?strSecao=resultado&nrSeq=36990

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16th Edition):

CUNHA, ALEXANDRE ASHADE LASSANCE. “[en] ANALYTICAL SOLUTION OF EIGENVALUE EQUATIONS BY GENETIC PROGRAMMING, WITH APPLICATION IN THE ANALYSIS OF ELECTROMAGNETIC PROPAGATION IN PRODUCTION PIPES OF OIL, PARAMETERIZED BY THE RADIUS AND THE PERCENTAGE OF INCRUSTATIONS.” 2019. Thesis, Pontifical Catholic University of Rio de Janeiro. Accessed January 21, 2020. http://www.maxwell.vrac.puc-rio.br/Busca_etds.php?strSecao=resultado&nrSeq=36990.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7th Edition):

CUNHA, ALEXANDRE ASHADE LASSANCE. “[en] ANALYTICAL SOLUTION OF EIGENVALUE EQUATIONS BY GENETIC PROGRAMMING, WITH APPLICATION IN THE ANALYSIS OF ELECTROMAGNETIC PROPAGATION IN PRODUCTION PIPES OF OIL, PARAMETERIZED BY THE RADIUS AND THE PERCENTAGE OF INCRUSTATIONS.” 2019. Web. 21 Jan 2020.

Vancouver:

CUNHA AAL. [en] ANALYTICAL SOLUTION OF EIGENVALUE EQUATIONS BY GENETIC PROGRAMMING, WITH APPLICATION IN THE ANALYSIS OF ELECTROMAGNETIC PROPAGATION IN PRODUCTION PIPES OF OIL, PARAMETERIZED BY THE RADIUS AND THE PERCENTAGE OF INCRUSTATIONS. [Internet] [Thesis]. Pontifical Catholic University of Rio de Janeiro; 2019. [cited 2020 Jan 21]. Available from: http://www.maxwell.vrac.puc-rio.br/Busca_etds.php?strSecao=resultado&nrSeq=36990.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

CUNHA AAL. [en] ANALYTICAL SOLUTION OF EIGENVALUE EQUATIONS BY GENETIC PROGRAMMING, WITH APPLICATION IN THE ANALYSIS OF ELECTROMAGNETIC PROPAGATION IN PRODUCTION PIPES OF OIL, PARAMETERIZED BY THE RADIUS AND THE PERCENTAGE OF INCRUSTATIONS. [Thesis]. Pontifical Catholic University of Rio de Janeiro; 2019. Available from: http://www.maxwell.vrac.puc-rio.br/Busca_etds.php?strSecao=resultado&nrSeq=36990

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

.