Thesis (M.S.)--Virginia Polytechnic Institute and State University, 1993. / Vita. Abstract. Includes bibliographical references (leaves 61-62). Also available via the Internet.

Thesis (M. Eng.)--Carleton University, 1993. / Also available in electronic format on the Internet.

Thesis (Ph.D.) -- Mississippi State University. Department of Electrical and Computer Engineering. / Title from title screen. Includes bibliographical references.

Orientador: Maria Cristina Dias Tavares / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Eletrica e de Computação / Made available in DSpace on 2018-08-10T17:05:14Z (GMT). No. of bitstreams: 1 ElgueraFlores_AlexanderVladimir_M.pdf: 2442597 bytes, checksum: c3718bb5135d22cdcdf2a22c0c313ed1 (MD5) Previous issue date: 2006 / Resumo: É usual utilizar a transposição das fases nas linhas de transmissão com o intuito de diminuir o desequilíbrio de tensão e corrente existente. Na freqüência fundamental uma linha de transmissão pode ser considerada idealmente transposta, mas normalmente nos estudos de transitórios eletromagnéticos e nos estudos de qualidade de energia as linhas também são representadas como se fossem idealmente transpostas. Para freqüência fundamental é adequado tratar uma linha como idealmente transposta, mas isto não pode ser generalizado para toda a gama de freqüência dos fenômenos transitórios. No presente trabalho foi analisado o erro de se tratar uma linha como idealmente transposta para toda a faixa de freqüências, especificamente até 10 kHz. Uma análise teórica foi implementada identificando o desequilíbrio entre as fases considerando uma linha idealmente transposta e considerando uma linha com trechos de transposição real. A dependência da freqüência dos parâmetros elétricos da linha de transmissão foi adequadamente representada / Abstract: It is usual to use the phase transposition in transmission line aiming to decrease the existing voltage and current unbalance. In fundamental frequency a transmission line can be considered ideally transposed, but normally in the electromagnetic transients and quality energy studies the lines also are represented as if they were ideally transposed. For fundamental frequency it is correct to treat a line as ideally transposed, but this cannot be generalized for the entire frequency range of transient phenomena. In the present work it was analyzed the error of treating transmission line as ideally transposed for all frequency range, specifically up to 10 kHz. A theoretical analysis was implemented identifying the unbalances between the phases considering the transmission line ideally transposed and considering the transmission line with its actual transposition sections. The frequency dependence of transmission line parameters was properly represented. / Mestrado / Energia Eletrica / Mestre em Engenharia Elétrica

This thesis presents the theory, analysis, testing and implementation of a scheme to reduce shunt compensation capacitor switching transients. The described method is switch the capacitors very near the instant when the bus voltage is at a power frequency zero. This was accomplished with a vacuum breaker on a 230 kV shunt capacitor bank.

This thesis is an introduction to the solution of electromagnetic transients by a combination of the Bergeran method of characteristics and the application of trapezoidal rule of integration. Three test examples solved by digital computer illustrate the step by step solution and computer programming. To compare this method with the Laplace transformation technique, a test problem solved by both methods and also digital computer is illustrated. In conclusion, the advantages and disadvantages of both methods are compared

A methodology to obtain design guidelines for gate oxide input pin protection and high voltage output pin protection in Electrostatic Discharge (ESD) time frame is developed through measurements and Technology Computer Aided Design (TCAD). A set of parameters based on transient measurements are used to define Transient Safe Operating Area (TSOA). The parameters are then used to assess effectiveness of protection devices for output and input pins. The methodology for input pins includes establishing ESD design targets under Charged Device Model (CDM) type stress in low voltage MOS inputs. The methodology for output pins includes defining ESD design targets under Human Metal Model (HMM) type stress in high voltage Laterally Diffused MOS (LDMOS) outputs. First, the assessment of standalone LDMOS robustness is performed, followed by establishment of protection design guidelines. Secondly, standalone clamp HMM robustness is evaluated and a prediction methodology for HMM type stress is developed based on standardized testing. Finally, LDMOS and protection clamp parallel protection conditions are identified

Recent widespread blackouts have indicated the need for more efficient and accurate power system monitoring, control and protection tools. Power system state estimation, which is the major tool that is used nowadays for providing the real-time model of the system, has significant biases resulting mainly from the complexity and geographic spread and separation of an electric power system. Synchrophasor technology is a promising technology that has numerous advantages compared to conventional metering devices. PMUs provide synchronized measurements, where synchronization is achieved via a GPS clock which provides the synchronizing signal with accuracy of 1 μsec. As a result, the computed phasors have a common reference (UTC time) and can be used in local computations, thus distributing the state estimation process. The first part of the work presents a PMU enabled dynamic state estimator (DSE) that can capture with high fidelity the dynamics of the system and extract in real time the dynamic model of the system. The described DSE is performed in a decentralized way, on the substation level based on local measurements which are globally valid. The substation based DSE uses data from relays, PMUs, meters, FDRs etc in the substation only, thus avoiding all issues associated with transmission of data and associated time latencies. This approach enables very fast DSE update rate which can go up to more than 60 executions per second. The distributed state estimation architecture that synchrophasor technology enables, along with the fast sampling rate and the accuracy of the measurements that PMUs provide, enable the computation of the real-time dynamic model of the system and the development of numerous power system applications for more efficient control and protection of the system. In the second part of the work, a transient stability monitoring scheme is presented that utilizes the information given by the dynamic state estimation and enables real-time monitoring of the transient swings of the system and characterizes the stability of the system in real time. In particular, the real-time dynamic model of the system, as given by the DSE, is utilized to evaluate the system's energy function based on Lyapunov's direct method and extract stability properties from the energy function. The two major components of the scheme are a) the calculation of the center of oscillations of the system and b) the derivation of an equivalent, reduced sized model which is used for the calculation of the potential and kinetic energy of the system based on which the stability of the system is determined. Finally, as an application of the transient stability monitoring scheme, an energy based out-of-step protection scheme is proposed. The energy of the generator is continuously monitored and if it exceeds a predefined threshold then instability is asserted and a trip signal can be sent to the generator. The major advantage of the scheme is that the out-of-step condition is predicted before its occurrence and therefore relays can act much faster than today's technology. The scheme is compared to presently available state of the art out-of-step protection schemes in order to verify its superiority.

No description available.

Thesis (M.S.) -- Mississippi State University. Department of Electrical and Computer Engineering. / Title from title screen. Includes bibliographical references.