A direct and rigid algorithm approach based on Equivalent Current Injection (ECI) for large-scale distribution power flow analysis is proposed in this dissertation. This algorithm used two primary matrices: BI and ZV-BC. Two matrices, which are built from the topological characteristics of distribution networks, are used to achieve the power flow solutions. BI matrix is the bus injection to branch current matrix and the ZV-BC matrix describes the relationship between the bus voltage mismatches and the branch current. The building algorithm is easily programmable and can be accomplished by a simple search technique with the two proposed matrices. Four connected cases are considered in this dissertation. The proposed algorithm is robust and accurate. Test results demonstrate the potential and validity of the proposed algorithm in distribution applications. Secondly, this thesis also presents a fault analysis with hybrid compensation for unbalanced distribution systems is proposed. The method employs the unbalanced three-phase model to analyze faults. BI and ZV-BC matrices containing information of the topological characteristics of distribution networks were built along with the proposed hybrid compensation method for analysis. Appropriate boundary conditions can be obtained for a fault to solve various types of single or simultaneous faults. The time-consuming LU decompositions, the Jacobian matrix, or the Y admittance matrix, required in the traditional algorithms, are not needed in the new development. Test results show that the proposed method is efficient, easy to program, also with advantages of high speed, robustness, improved accuracy, and lower memory requirements. This thesis also presents a hybrid programming (HP) technique to solve the reconfiguration problem for loss reduction and service restoration in Smart Grid application.

Submitted by Renata Lopes (renatasil82@gmail.com) on 2016-02-11T10:15:45Z No. of bitstreams: 1 marciodecarvalhofilho.pdf: 1308253 bytes, checksum: ce4bec8646b462983e485a5bcad4f5c1 (MD5) / Approved for entry into archive by Adriana Oliveira (adriana.oliveira@ufjf.edu.br) on 2016-02-26T11:53:11Z (GMT) No. of bitstreams: 1 marciodecarvalhofilho.pdf: 1308253 bytes, checksum: ce4bec8646b462983e485a5bcad4f5c1 (MD5) / Made available in DSpace on 2016-02-26T11:53:11Z (GMT). No. of bitstreams: 1 marciodecarvalhofilho.pdf: 1308253 bytes, checksum: ce4bec8646b462983e485a5bcad4f5c1 (MD5) Previous issue date: 2014-08-13 / CAPES - Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Neste trabalho desenvolveu-se uma ferramenta para análise de falhas, sendo os modelos de diversos equipamentos do sistema elétrico considerados de forma detalhada, permitindo a análise multifásica do sistema, representando-o da maneira mais generalizada e realista possível. A metodologia desenvolvida para análise de falhas baseia-se no método de injeção de correntes a n condutores em coordenadas retangulares, onde utiliza-se o método de Newton-Raphson no processo de solução e todas as grandezas são definidas diretamente em coordenadas de fase. A modelagem de todo o sistema elétrico é realizada baseando-se em elementos que compõem as estruturas dos equipamentos em seus modelos, sendo que estes elementos podem estar conectados das mais diversas maneiras. As próprias condições de curto-circuito são modeladas por meio de elementos, conectados em diferentes configurações. Também a inclusão dos controles é feita de forma otimizada. Com a modelagem considerada, o sistema a ser solucionado é o estritamente necessário, e, portanto, a metodologia apresenta-se bastante eficiente. A metodologia também se mostra bastante flexível, pois é capaz de representar equipamentos com qualquer número de condutores nas mais diversas configurações, permitindo representar desequilíbrios, acoplamentos mútuos, sistemas de aterramento e cabos neutros explicitamente, e permitindo modelar diversos tipos de falhas, dentre outras características. Desta forma, a metodologia possibilita análises bastante completas, sendo que a representação do sistema pode ser feita com o nível de detalhe que for possível e desejável em cada situação. A ferramenta desenvolvida é bastante abrangente sendo capaz de simular sistemas equilibrados ou desequilibrados, radiais ou reticulados, diversos tipos de falhas (como curtos-circuitos em derivação, interno e simultâneo, ou abertura série), podendo ser aplicada em sistemas de transmissão, subtransmissão, distribuição, e industriais, inclusive de grande porte. / In this work a tool for fault analysis was developed, and models of many electrical systems equipment were considered in detail, allowing the analysis of multiphase systems by representing it in a more general and realistic way possible. The methodology developed for fault analysis is based on the current injection method in rectangular coordinates, where the Newton-Raphson method is used in the solution process and all quantities are defined directly in phase coordinates. The modeling of the entire electrical system is made based on elements which assemble the structures of equipment in their models, and these elements can be connected in various ways. Even the short circuit conditions are modeled by elements connected in different configurations. Also the inclusion of controls is done optimally. With the considered modeling the system to be solved is the strictly necessary, and therefore, the method shows to be efficient. The methodology is also very flexible because it is able to represent equipments with any number of conductors in many different configurations, allowing the representation of imbalances, mutual couplings, groundings and neutral cables explicitly, and allowing to model various types of faults, among other features. Therefore, the methodology allows fairly complete analysis, and the representation of the system can be made with the level of detail that is possible and desirable in every situation. The tool developed is quite ample being able to simulate balanced or unbalanced, radial or meshed systems, various types of failures (such as shunt short circuits, internal faults, simultaneous fault, and series opening), it can be applied to the transmission, subtransmission, distribution and industrial systems, including large scale systems.