<p> In power systems, dynamic stability analysis is an important field of interest for both design and operation studies. This stability analysis requires the formulation of the linearized power system equations in the state-space form.</p> <p> In this thesis, the state-space matrices of multi-machine systems are constructed by implementing two matrix formulation techniques, the "PQR" and the direct elimination "ELIM" methods. Two computer programs have been devised to apply these formulation techniques. The programs are capable of handling systems up to a maximum order of 70, with available central memory of about 49,000 words (decimal). Another feature of these programs is their capability of accommodating generating units with different degrees of complexity, by allowing a variety of models for the sub-system components. Both programs have been applied to two test examples to illustrate their validity.</p> <p> The two formulation technique programs were compared from the point of view of computational time, storage requirements and eigenvalue sensitivity evaluation.</p> / Thesis / Master of Engineering (MEngr)

Reconfiguration is needed to meet the fight-through and survivability requirements of a shipboard power system. Reconfiguration involves the re-arrangement of power system topology through the opening and switching of breakers, and adjusting of total generators and load values. When the power system is reconfigured, the protection system needs to be attuned to the new power system state. This thesis focuses on developing an adaptive protection scheme for shipboard power systems that will automatically update relay settings after changes in power system topology and operational state. The developed adaptive protection scheme employs four main algorithms to achieve its goal. A topology-recognition algorithm uses the statuses (open/close) of breakers to determine the topological-configuration of the system. A powerlow and a fault-analysis algorithm are used to determine the system?s normal and fault currents, respectively. A protection-setting algorithm is used to determine and set the operating parameters of all the relays in the system. The scheme was implemented in MATLAB miles and tested on various configurations of a notional shipboard power system. The tests results were verified in CAPE.

No description available.

This thesis performs simulations of a relay supervisory system (RSS) that works passively in conjunction with the existing protective relaying system at a substation. During normal system operating conditions, the RSS supervises the relay system to prevent trips due to hidden failures. During wide area network disturbances, it adapts the relay system to increase security of the power system. The RSS works passively in the sense that it waits for events to occur in the existing relay system before taking any action. The simulation performed includes a model of the RSS, along with simplified models of existing relays, performed in Matlab. A power system model in EMTP provides inputs to the RSS model. Multiple faults are applied to the EMTP model, and the RSS is tested under each fault condition, and with a variety of relay hidden failures. For all tests performed, the simulation of the RSS successfully prevents relay hidden failure from removing circuit elements inadvertently, while allowing correct relay operations to remove circuit elements. / Master of Science

published_or_final_version / Electrical and Electronic Engineering / Master / Master of Philosophy

Thesis (Ph. D.)--University of Washington, 2007. / Vita. Includes bibliographical references (leaves 92-96).

Thesis (Ph.D.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 1980. / MICROFICHE COPY AVAILABLE IN ARCHIVES AND ENGINEERING. / Vita. / Includes bibliographical references. / by Pierre Dersin. / Ph.D.

This thesis addresses the problem of reactive power scheduling in a power system with several areas controlled by independent transmission system operators (TSOs). To design a fair method for optimizing the control settings in the interconnected multi-TSO system, two types of schemes are developed. First, a centralized multi-TSO optimization scheme is introduced, and it is shown that this scheme has some properties of fairness in the economic sense. Second, the problem is addressed through a decentralized optimization scheme with no information exchange between the TSOs. In this framework, each TSO assumes an external network equivalent in place of its neighboring TSOs and optimizes the objective function corresponding to its own control area regardless of the impact that its choice may have on the other TSOs. The thesis presents simulation results obtained with the IEEE 39 bus system and IEEE 118 bus systems partitioned between three TSOs. It also presents some results for a UCTE-like 4141 bus system with seven TSOs. The decentralized control scheme is applied to both time-invariant and time-varying power systems. Nearly optimal performance is obtained in those contexts.

Orientadores: Carlos Alberto de Castro Junior, Manfred Fritz Bedriñana Aronés / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Elétrica e de Computação / Made available in DSpace on 2018-08-16T06:40:59Z (GMT). No. of bitstreams: 1 Tavares_BeatrizdeLima_M.pdf: 2516787 bytes, checksum: 8462455ea7f9f76c7dd5ebef70a70ace (MD5) Previous issue date: 2010 / Resumo: Neste trabalho são apresentados dois métodos para a obtenção do ponto de máximo carregamento (PMC). Ambos os processos de cálculo baseiam-se nas propriedades do vetor normal à fronteira de factibilidade calculado próximo ao PMC através de um método de fluxo de carga com otimização de passo (FCOP). No primeiro método o processo é caracterizado pela obtenção de sucessivas aproximações do PMC a partir da região de infactibilidade. Pelo fato da fronteira de factibilidade não ser sempre convexa, algumas vezes o ponto obtido poderá cair na região factível. Neste caso, um novo método de cálculo do fator de carregamento que garante que o próximo ponto estará na região infactível é a principal contribuição. Já o segundo é um método rápido e prático para o cálculo do ponto de máximo carregamento (PMC), em que é adicionado um procedimento prático ao processo de cálculo global para incluir a informação do operador da rede com a definição de um erro aceitável no resultado final. O PMC é facilmente obtido após alguns passos, demonstrando a eficácia do método proposto. Os resultados de simulações com sistemas teste do IEEE e sistemas reais são apresentados para validar as duas metodologias / Abstract: In this paper, two maximum loading point (MLP) calculation methods are proposed. In both cases, the calculation process is based on the properties of the normal vector to the feasibility boundary computed close to MLP, which is calculated by a load flow method with step size optimization (LFSSO). In the first method the process is characterized by obtaining consecutive approximations of the MLP from the infeasible region. Since the feasibility boundary contour in the neighborhood of the MLP may not be smooth, some of the computed points may fall within the feasible region. In this case, a new load factor calculation method that guarantees that the next solution will lay within the infeasibility region is the main contribution. The second one is a practical and fast method to obtain the MLP, where a practical procedure is added to the overall calculation process to include the operator's information on the acceptable error in the final result. The MLP is accurately obtained after just a few steps, demonstrating the efficiency of the proposed method. Simulation results for IEEE test and realistic systems are shown to validate both proposed methods / Mestrado / Energia Eletrica / Mestre em Engenharia Elétrica

Optimization problems are vital in physical sciences, commercial and finance matters. In a nutshell, almost everyone is the stake-holder in certain optimization problems aiming at minimizing the cost of production and losses of system, and also maximizing the profit. In control systems, the optimal configuration problems are essential that have been solved by various newly developed methods. The literature is exhaustively explored for an appropriate optimization method to solve such kind of problems. Particle Swarm Optimization is found to be one of the best among several optimization methods by analysing the experimental results. Two novel PSO variants are introduced in this thesis. The first one is named as N State Markov Jumping Particle Swarm Optimization, which is based on the stochastic technique and Markov chain in updating the particle velocity. We have named the second variant as N State Switching Particle Swarm Optimization, which is based on the evolutionary factor information for updating the velocity. The proposed algorithms are then applied to some widely used mathematical benchmark functions. The statistical results of 30 independent trails illustrate the robustness and accuracy of the proposed algorithms for most of the benchmark functions. The better results in terms of mean minimum evaluation errors and the shortest computation time are illustrated. In order to verify the satisfactory performance and robustness of the proposed algorithms, we have further formulated some basic applications in power system operations. The first application is about the static Economic Load Dispatch and the second application is on the Dynamic Economic Load Dispatch. These are highly complex and non-linear problems of power system operations consisting of various systems and generator constraints. Basically, in the static Economic Load Dispatch, a single load is considered for calculating the cost function. In contrast, the Dynamic Economic Load Dispatch changes the load demand for the cost function dynamically with time. In such a challenging and complex environment the proposed algorithms can be applied. The empirical results obtained by applying both of the proposed methods have substantiated their adaptability and robustness into the real-world environment. It is shown in the numerical results that the proposed algorithms are robust and accurate as compared to the other algorithms. The proposed algorithms have produced consistent best values for their objectives, where satisfying all constraints with zero penalty.