20 resultados para Manoel Dias

em Universidade Federal do Rio Grande do Norte(UFRN)


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Analisar, em pacientes submetidos a simpaticotomia videotoracoscópica para tratamento da Hiperidrose Primária (HP), as conseqüências hemodinâmicas da desnervação vascular das artérias carótidas e vertebrais após a trans-secção cirúrgica da cadeia simpática torácica (simpaticotomia), através da mensuração de parâmetros ultra-sonográficos. Método: Vinte e quatro pacientes portadores de HP submetidos a quarenta e oito simpaticotomias torácicas endoscópicas foram avaliados através da mensuração da velocidade de pico sistólico (VPS), velocidade de pico diastólico (VPD), índice de pulsatibilidade (IP) e índice de resistência (IR) nas artérias carótidas comuns, internas e externas, além da artéria vertebral bilateralmente usando o eco-doppler duplex scan. As avaliações foram realizadas antes da intervenção cirúrgica e trinta dias após o procedimento. O teste de Wilcoxon foi usado na análise das diferenças entre as variáveis antes e depois da simpaticotomia. Resultados: A simpaticotomia no nível de T3 foi a trans-secção mais realizada (95,83%), seja isoladamente (25%) ou associada a T4 (62,50%) ou a T2 (8,33%). Houve aumento significativo no IR e no IP da artéria carótida comum bilateralmente (p<0,05). A VPD da artéria carótida interna diminuiu em ambos os lados (p<0,05). A VPS e a VPD da artéria vertebral direita também aumentaram (p<0,05). Achados assimétricos foram observados, de modo que artérias do lado direito foram as mais freqüentemente afetadas. Conclusões: Alterações hemodinâmicas foram observadas nas artérias vertebral e carótida após simpaticotomia para tratamento de HP. VPS foi o parâmetro mais freqüentemente alterado, principalmente nas artérias do lado direito, representando alterações assimétricas significantes nas artérias carótida e vertebral. Entretanto, são necessárias pesquisas subseqüentes para verificar se essas alterações são definitivas ou temporárias, uma vez que as inferências clínicas somente terão validação se as alterações forem permanentes

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This work aims to understand the phenomenon of corruption in the Brazilian public sphere and its implications for society. It has brought concepts of corruption, and has referred to its highest incidence in the public sphere in the three levels of government (despite its infiltration also in the privative sector) and has called attention to two subjects which intertwine public administration (as a means of ordering social life) and corruption (as a form of denial to the collective welfare). Through literature search whose analysis shows that the phenomenon contains the entire country history, from discovery to present day it was found to be common several dictatorial and democratic political regimes. Finally, it has emphasized the importance and necessity of citizen participation in process, as well as the organization of civil society and media, in addition to highlighting the relevance of autonomy and independence of Powers set for its effective confrontation and fighting

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This work aims to analyze risks related to information technology (IT) in procedures related to data migration. This is done considering ALEPH, Integrated Libray System (ILS) that migrated data to the Library Module present in the software called Sistema Integrado de Gestão de Atividades Acadêmicas (SIGAA) at the Zila Mamede Central Library at the Federal University of Rio Grande do Norte (UFRN) in Natal/Brazil. The methodological procedure used was of a qualitative exploratory research with the realization of case study at the referred library in order to better understand this phenomenon. Data collection was able once there was use of a semi-structured interview that was applied with (11) subjects that are employed at the library as well as in the Technology Superintendence at UFRN. In order to examine data Content analysis as well as thematic review process was performed. After data migration the results of the interview were then linked to both analysis units and their system register with category correspondence. The main risks detected were: data destruction; data loss; data bank communication failure; user response delay; data inconsistency and duplicity. These elements point out implication and generate disorders that affect external and internal system users and lead to stress, work duplicity and hassles. Thus, some measures were taken related to risk management such as adequate planning, central management support, and pilot test simulations. For the advantages it has reduced of: risk, occurrence of problems and possible unforeseen costs, and allows achieving organizational objectives, among other. It is inferred therefore that the risks present in data bank conversion in libraries exist and some are predictable, however, it is seen that librarians do not know or ignore and are not very worried in the identification risks in data bank conversion, their acknowledge would minimize or even extinguish them. Another important aspect to consider is the existence of few empirical research that deal specifically with this subject and thus presenting the new of new approaches in order to promote better understanding of the matter in the corporate environment of the information units

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Analyze, in patients with primary hyperhidrosis (PH) who was undergone to videothoracoscopic sympathicotomy, the degree of vascular denervation after surgical transection of the thoracic sympathetic chain by measuring ultrasonografic parameters in carotid and vertebral arteries. Methods: Twenty-four patients with PH underwent forty-eight endoscopic thoracic sympathicotomy and were evaluated by duplex eco-doppler measuring systolic peak velocity (SPV), diastolic peak velocity (DPV), pulsatility index (PI) and resistivity index (RI) in bilateral common, internal and external carotids, besides bilateral vertebral arteries. The exams were performed before operations and a month later. Wilcoxon test was used to analyse the differences between the variables before and after the sympatholisis. Results: T3 sympathicotomy segment was the most frequent transection done (95,83%), as only ablation (25%) or in association with T4 (62,50%) or with T2 (8,33%). It was observed increase in RI and PI of the common carotid artery ( p<0,05). The DPV of internal carotid artery decreased in both sides (p<0,05). The SPV and the DPV of the right and left vertebral arteries also increased (p<0,05). Asymmetric findings were observed so that, arteries of the right side were the most frequently affected. Conclusions: Hemodynamic changes in vertebral and carotid arteries were observed after sympathicotomy for PH. SPV was the most often altered parameter, mostly in the right side arteries, meaning significant asymmetric changes in carotid and vertebral vessels. Therefore, the research findings deserve further investigations to observe if they have clinical inferences

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This paper adopts the assumption that religion continues to be a major highlight in the dimension of the contemporary world - characterized by pluralism, the ideas of tolerance and freedom. But for certain streams of Christianity, the postmodern culture seems to be characterized as a highly damaging to their doctrines and principles, since this religious matrix carries a truth claim that would support all its significance, its definition values and their dissemination effort ( evangelism ). This is not to say that Christianity is the only religion that claims to the truth, which would be a gross mistake. Now, religion has been reputed as a phenomenon doomed to disappear, according to the " ideology " of Modernity, given the idea that scientific development would lead us inevitably to the statement that religion was merely a social institution based in the superstition, in fantasy, the imaginary and therefore had nothing "real " unless its existence as an institution capable of aggregating society (give it cohesion), provide values and meaning to different ontological anxieties and doubts of humankind. In the contemporary scenario - seeded by modernity - as Christian ideas, doctrines and principles are in harmony or conflict with postmodernity? These are our starting questions and issues that we intend to stop and reflect. From the assumption that the religious phenomenon has great force in the present day, this research aims to perform central analysis of how religious education, a Protestant denomination specific, harmonizes or clashes with the ideology or ideas more general and emphatic that we can observe in the western world is presented to us from the diagnoses made by the contemporary authors who debate about postmodernism and postmodernity, notably David Harvey, Jean - François Lyotard, Bauman Zygmunt and Fredric Jameson

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Este estudo trata sobre as marcas da experiência escolar no processo de individuação do sujeito e tem como objetivo geral conhecer de que forma essas experiências, a despeito das questões curriculares e pedagógicas, influenciam esse processo. Buscou-se interpretar as experiências reforçadas durante a escolarização e as trajetórias de enfrentamento das diversas situações vividas na escola. Tentou-se, também, compreender o sentido dos acontecimentos escolares críticos e igualmente como o meio familiar pode influenciar nas escolhas e formação dos sujeitos através do investimento pedagógico. Ademais, refletiu-se sobre os motivos que levaram alguns a permanecerem no ambiente escolar seja como estudante ou mais tarde, do lado de lá, como professor. Para tanto, foi realizada uma pesquisa qualitativa de inspiração fenomenológica utilizando-se de entrevistas narrativas com quatro sujeitos, a partir das quais se identificou as principais características, estrutura, condições de origem, o contexto social, as estratégias escolares, as formas como foram manejadas e suas conseqüências. A análise dos relatos deixou claro dois eixos fundamentais da experiência escolar que se destacam na constituição dos sujeitos: de um lado a dinâmica do ambiente escolar vivido deixou marcas indeléveis na memória que foram determinantes para as escolhas pessoais; por outro lado, a referência familiar, através das suas várias formas de investimento pedagógico, teve uma influência decisiva. As marcas combinadas da escola e da família deixaram um legado importante para formação dos sujeitos e para as escolhas que fizeram durante as suas vidas, especialmente no direcionamento da suas carreiras profissionais. Invariavelmente, percebeu-se na investigação, que muito do aluno que se foi persiste no adulto e profissional de hoje. Assim, o Eu escolar é parte do Eu profissional que existe em cada um. O cidadão, a pessoa e o profissional são derivados dos processos de socialização e individuação, os quais em grande parte se definem durante a vida escolar. E é com o uso desse "capital escolar" , adquirido nos tempos de escola, que temos condições de desenvolver os muitos papéis sociais nos dias atuais.

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This study it treats on the marks of the school experience in the individuation process of the subject and has as general aim to know of that it forms these experiences, the spite of the curricular and pedagogical questions, influences this process. It searched to interpret the experiences strengthened during the school education and the trajectories of confrontation of the diverse situations lived in the school. It was tried,also,to understand the direction of the critical school events and equally as the familiar way can influence in the choices and formation of the citizens through the pedagogical investment. Furthermore, it was reflected on the reasons that had taken some to remain in the school environment are as student or, later, of the side of there ,as teacher. For in such a way, it realized a qualitative research with a phenomenological inspiration using narratives interviews carried with four subjects, from which if it identified the main characteristics, structure, conditions of origin, the social context, the school strategies, the forms as they had been managed and its consequences. The analysis of the stories clearly left two basic axles about the school experience that if detach in the constitution of the subjects: in a hand, the dynamics of the lived school environment left undeleted marks in the memory that had been determinative for the personal choices; on the other hand,the familiar reference, through its different forms of pedagogical investment,had a decisive influence. The agreed marks of the school and the family had left an important legacy for formation of the subjects and the choices that had made during their lives, especially in the aiming of its professional careers. Invariably, it was perceived in the inquiry, that much of the pupil who if was persists in the adult and professional of today. Thus, the school I it s part of professional I that it exists in each one. The citizen, the person and the professional are derived from the processes of socialization and individuation, which to a large extent are defined during the school life. And it s with the use of this school capital , acquired in the school times, that we have conditions to develop the many social roles in the current days

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El presente trabajo, intitulado, Los saberes de los profesores de la Escuela Fundamental: concepciones sobre los abordajes geográficos objetiva investigar los saberes del profesor de los años iniciales de la Escuela Fundamental en relación a la naturaleza especifica de los abordajes geográficos y reflexionar como en el proceso de investigación colaborativa los profesores aprendieron los saberes específicos de los abordajes geográficos vinculando sus asimilaciones teóricas a un determinado nivel de concepción . Buscamos con base en la investigación cualitativa del tipo colaborativa y en la aplicación de diferentes procedimientos técnicos-metodológico, responder a nuestras cuestiones de estudio: ¿Cuales los saberes geográficos que los profesores construyeron en la trayectoria de sus formaciones? ¿Cómo, en el proceso de investigación colaborativa, los profesores aprendieran los saberes específicos de los abordajes geográficos? Conforme principios de la perspectiva socio-histórica. Así, utilizamos específicamente las narrativas tópicas (orales y escritas) con base en los ejes norteadores Como aprendí y lo que aprendí referentes a los saberes geográficos constituidos en la trayectoria de formación, para realizar el diagnostico de los conocimientos previos de los profesores. El proceso reflexivo y la profundización del estudio ocurrieron, respectivamente, por medio de los Seminarios de Estudios Reflexivos y de los Ciclos de Estudios Reflexivos indicando la concepción de aprehensión de los saberes propuestos en esa construcción científica. Los postulados teóricos de Ferreira (2007), Charlot (2000, 2005), Tardif (2002), Tonine (2003), Soares (2000), Moraes (2005), Pimenta (2007), entre otros, proporcionaron comprensión sobre la temática en estudio. La pesquisa ocurrió en una acción colaborativa en la escuela pública de la ciudad de Natal/RN, en el Barrio de Nova Descoberta, en el turno matutino, con tres colaboradores, que participaron voluntariamente de ese proceso: Angico, Jacarandá y Carvalho desarrollaron sus prácticas pedagógicas, en los 1ºs y 4ºs años de la Enseñaza Fundamental. Los resultados obtenidos de los análisis, apuntaron un alcance descriptivo de las concepciones de los colaboradores sobre los saberes de los abordajes geográficos, que se refieren a enumeración de los aspectos característicos del fenómeno concebido, aunque nos haya empeñado para los alcances transformadores de nuestras concepciones

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The progresses of the Internet and telecommunications have been changing the concepts of Information Technology IT, especially with regard to outsourcing services, where organizations seek cost-cutting and a better focus on the business. Along with the development of that outsourcing, a new model named Cloud Computing (CC) evolved. It proposes to migrate to the Internet both data processing and information storing. Among the key points of Cloud Computing are included cost-cutting, benefits, risks and the IT paradigms changes. Nonetheless, the adoption of that model brings forth some difficulties to decision-making, by IT managers, mainly with regard to which solutions may go to the cloud, and which service providers are more appropriate to the Organization s reality. The research has as its overall aim to apply the AHP Method (Analytic Hierarchic Process) to decision-making in Cloud Computing. There to, the utilized methodology was the exploratory kind and a study of case applied to a nationwide organization (Federation of Industries of RN). The data collection was performed through two structured questionnaires answered electronically by IT technicians, and the company s Board of Directors. The analysis of the data was carried out in a qualitative and comparative way, and we utilized the software to AHP method called Web-Hipre. The results we obtained found the importance of applying the AHP method in decision-making towards the adoption of Cloud Computing, mainly because on the occasion the research was carried out the studied company already showed interest and necessity in adopting CC, considering the internal problems with infrastructure and availability of information that the company faces nowadays. The organization sought to adopt CC, however, it had doubt regarding the cloud model and which service provider would better meet their real necessities. The application of the AHP, then, worked as a guiding tool to the choice of the best alternative, which points out the Hybrid Cloud as the ideal choice to start off in Cloud Computing. Considering the following aspects: the layer of Infrastructure as a Service IaaS (Processing and Storage) must stay partly on the Public Cloud and partly in the Private Cloud; the layer of Platform as a Service PaaS (Software Developing and Testing) had preference for the Private Cloud, and the layer of Software as a Service - SaaS (Emails/Applications) divided into emails to the Public Cloud and applications to the Private Cloud. The research also identified the important factors to hiring a Cloud Computing provider

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The usual programs for load flow calculation were in general developped aiming the simulation of electric energy transmission, subtransmission and distribution systems. However, the mathematical methods and algorithms used by the formulations were based, in majority, just on the characteristics of the transmittion systems, which were the main concern focus of engineers and researchers. Though, the physical characteristics of these systems are quite different from the distribution ones. In the transmission systems, the voltage levels are high and the lines are generally very long. These aspects contribute the capacitive and inductive effects that appear in the system to have a considerable influence in the values of the interest quantities, reason why they should be taken into consideration. Still in the transmission systems, the loads have a macro nature, as for example, cities, neiborhoods, or big industries. These loads are, generally, practically balanced, what reduces the necessity of utilization of three-phase methodology for the load flow calculation. Distribution systems, on the other hand, present different characteristics: the voltage levels are small in comparison to the transmission ones. This almost annul the capacitive effects of the lines. The loads are, in this case, transformers, in whose secondaries are connected small consumers, in a sort of times, mono-phase ones, so that the probability of finding an unbalanced circuit is high. This way, the utilization of three-phase methodologies assumes an important dimension. Besides, equipments like voltage regulators, that use simultaneously the concepts of phase and line voltage in their functioning, need a three-phase methodology, in order to allow the simulation of their real behavior. For the exposed reasons, initially was developped, in the scope of this work, a method for three-phase load flow calculation in order to simulate the steady-state behaviour of distribution systems. Aiming to achieve this goal, the Power Summation Algorithm was used, as a base for developing the three phase method. This algorithm was already widely tested and approved by researchers and engineers in the simulation of radial electric energy distribution systems, mainly for single-phase representation. By our formulation, lines are modeled in three-phase circuits, considering the magnetic coupling between the phases; but the earth effect is considered through the Carson reduction. It s important to point out that, in spite of the loads being normally connected to the transformer s secondaries, was considered the hypothesis of existence of star or delta loads connected to the primary circuit. To perform the simulation of voltage regulators, a new model was utilized, allowing the simulation of various types of configurations, according to their real functioning. Finally, was considered the possibility of representation of switches with current measuring in various points of the feeder. The loads are adjusted during the iteractive process, in order to match the current in each switch, converging to the measured value specified by the input data. In a second stage of the work, sensibility parameters were derived taking as base the described load flow, with the objective of suporting further optimization processes. This parameters are found by calculating of the partial derivatives of a variable in respect to another, in general, voltages, losses and reactive powers. After describing the calculation of the sensibility parameters, the Gradient Method was presented, using these parameters to optimize an objective function, that will be defined for each type of study. The first one refers to the reduction of technical losses in a medium voltage feeder, through the installation of capacitor banks; the second one refers to the problem of correction of voltage profile, through the instalation of capacitor banks or voltage regulators. In case of the losses reduction will be considered, as objective function, the sum of the losses in all the parts of the system. To the correction of the voltage profile, the objective function will be the sum of the square voltage deviations in each node, in respect to the rated voltage. In the end of the work, results of application of the described methods in some feeders are presented, aiming to give insight about their performance and acuity

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Eventually, violations of voltage limits at buses or admissible loadings of transmission lines and/or power transformers may occur by the power system operation. If violations are detected in the supervision process, corrective measures may be carried out in order to eliminate them or to reduce their intensity. Loading restriction is an extreme solution and should only be adopted as the last control action. Previous researches have shown that it is possible to control constraints in electrical systems by changing the network topology, using the technique named Corrective Switching, which requires no additional costs. In previous works, the proposed calculations for verifying the ability of a switching variant in eliminating an overload in a specific branch were based on network reduction or heuristic analysis. The purpose of this work is to develop analytical derivation of linear equations to estimate current changes in a specific branch (due to switching measures) by means of few calculations. For bus-bar coupling, derivations will be based on short-circuit theory and Relief Function methodology. For bus-bar splitting, a Relief Function will be derived based on a technique of equivalent circuit. Although systems of linear equations are used to substantiate deductions, its formal solution for each variant, in real time does not become necessary. A priority list of promising variants is then assigned for final check by an exact load flow calculation and a transient analysis using ATP Alternative Transient Program. At last, results obtained by simulation in networks with different features will be presented

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Most algorithms for state estimation based on the classical model are just adequate for use in transmission networks. Few algorithms were developed specifically for distribution systems, probably because of the little amount of data available in real time. Most overhead feeders possess just current and voltage measurements at the middle voltage bus-bar at the substation. In this way, classical algorithms are of difficult implementation, even considering off-line acquired data as pseudo-measurements. However, the necessity of automating the operation of distribution networks, mainly in regard to the selectivity of protection systems, as well to implement possibilities of load transfer maneuvers, is changing the network planning policy. In this way, some equipments incorporating telemetry and command modules have been installed in order to improve operational features, and so increasing the amount of measurement data available in real-time in the System Operation Center (SOC). This encourages the development of a state estimator model, involving real-time information and pseudo-measurements of loads, that are built from typical power factors and utilization factors (demand factors) of distribution transformers. This work reports about the development of a new state estimation method, specific for radial distribution systems. The main algorithm of the method is based on the power summation load flow. The estimation is carried out piecewise, section by section of the feeder, going from the substation to the terminal nodes. For each section, a measurement model is built, resulting in a nonlinear overdetermined equations set, whose solution is achieved by the Gaussian normal equation. The estimated variables of a section are used as pseudo-measurements for the next section. In general, a measurement set for a generic section consists of pseudo-measurements of power flows and nodal voltages obtained from the previous section or measurements in real-time, if they exist -, besides pseudomeasurements of injected powers for the power summations, whose functions are the load flow equations, assuming that the network can be represented by its single-phase equivalent. The great advantage of the algorithm is its simplicity and low computational effort. Moreover, the algorithm is very efficient, in regard to the accuracy of the estimated values. Besides the power summation state estimator, this work shows how other algorithms could be adapted to provide state estimation of middle voltage substations and networks, namely Schweppes method and an algorithm based on current proportionality, that is usually adopted for network planning tasks. Both estimators were implemented not only as alternatives for the proposed method, but also looking for getting results that give support for its validation. Once in most cases no power measurement is performed at beginning of the feeder and this is required for implementing the power summation estimations method, a new algorithm for estimating the network variables at the middle voltage bus-bar was also developed

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The usual programs for load flow calculation were in general developped aiming the simulation of electric energy transmission, subtransmission and distribution systems. However, the mathematical methods and algorithms used by the formulations were based, in majority, just on the characteristics of the transmittion systems, which were the main concern focus of engineers and researchers. Though, the physical characteristics of these systems are quite different from the distribution ones. In the transmission systems, the voltage levels are high and the lines are generally very long. These aspects contribute the capacitive and inductive effects that appear in the system to have a considerable influence in the values of the interest quantities, reason why they should be taken into consideration. Still in the transmission systems, the loads have a macro nature, as for example, cities, neiborhoods, or big industries. These loads are, generally, practically balanced, what reduces the necessity of utilization of three-phase methodology for the load flow calculation. Distribution systems, on the other hand, present different characteristics: the voltage levels are small in comparison to the transmission ones. This almost annul the capacitive effects of the lines. The loads are, in this case, transformers, in whose secondaries are connected small consumers, in a sort of times, mono-phase ones, so that the probability of finding an unbalanced circuit is high. This way, the utilization of three-phase methodologies assumes an important dimension. Besides, equipments like voltage regulators, that use simultaneously the concepts of phase and line voltage in their functioning, need a three-phase methodology, in order to allow the simulation of their real behavior. For the exposed reasons, initially was developped, in the scope of this work, a method for three-phase load flow calculation in order to simulate the steady-state behaviour of distribution systems. Aiming to achieve this goal, the Power Summation Algorithm was used, as a base for developping the three phase method. This algorithm was already widely tested and approved by researchers and engineers in the simulation of radial electric energy distribution systems, mainly for single-phase representation. By our formulation, lines are modeled in three-phase circuits, considering the magnetic coupling between the phases; but the earth effect is considered through the Carson reduction. Its important to point out that, in spite of the loads being normally connected to the transformers secondaries, was considered the hypothesis of existence of star or delta loads connected to the primary circuit. To perform the simulation of voltage regulators, a new model was utilized, allowing the simulation of various types of configurations, according to their real functioning. Finally, was considered the possibility of representation of switches with current measuring in various points of the feeder. The loads are adjusted during the iteractive process, in order to match the current in each switch, converging to the measured value specified by the input data. In a second stage of the work, sensibility parameters were derived taking as base the described load flow, with the objective of suporting further optimization processes. This parameters are found by calculating of the partial derivatives of a variable in respect to another, in general, voltages, losses and reactive powers. After describing the calculation of the sensibility parameters, the Gradient Method was presented, using these parameters to optimize an objective function, that will be defined for each type of study. The first one refers to the reduction of technical losses in a medium voltage feeder, through the installation of capacitor banks; the second one refers to the problem of correction of voltage profile, through the instalation of capacitor banks or voltage regulators. In case of the losses reduction will be considered, as objective function, the sum of the losses in all the parts of the system. To the correction of the voltage profile, the objective function will be the sum of the square voltage deviations in each node, in respect to the rated voltage. In the end of the work, results of application of the described methods in some feeders are presented, aiming to give insight about their performance and acuity

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The reconfiguration of a distribution network is a change in its topology, aiming to provide specific operation conditions of the network, by changing the status of its switches. It can be performed regardless of any system anomaly. The service restoration is a particular case of reconfiguration and should be performed whenever there is a network failure or whenever one or more sections of a feeder have been taken out of service for maintenance. In such cases, loads that are supplied through lines sections that are downstream of portions removed for maintenance may be supplied by the closing of switches to the others feeders. By classical methods of reconfiguration, several switches may be required beyond those used to perform the restoration service. This includes switching feeders in the same substation or for substations that do not have any direct connection to the faulted feeder. These operations can cause discomfort, losses and dissatisfaction among consumers, as well as a negative reputation for the energy company. The purpose of this thesis is to develop a heuristic for reconfiguration of a distribution network, upon the occurrence of a failure in this network, making the switching only for feeders directly involved in this specific failed segment, considering that the switching applied is related exclusively to the isolation of failed sections and bars, as well as to supply electricity to the islands generated by the condition, with significant reduction in the number of applications of load flows, due to the use of sensitivity parameters for determining voltages and currents estimated on bars and lines of the feeders directly involved with that failed segment. A comparison between this process and classical methods is performed for different test networks from the literature about networks reconfiguration

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The electric energy is essential to the development of modern society and its increasing demand in recent years, effect from population and economic growth, becomes the companies more interested in the quality and continuity of supply, factors regulated by ANEEL (Agência Nacional de Energia Elétrica). These factors must be attended when a permanent fault occurs in the system, where the defect location that caused the power interruption should be identified quickly, which is not a simple assignment because the current systems complexity. An example of this occurs in multiple terminals transmission lines, which interconnect existing circuits to feed the demand. These transmission lines have been adopted as a feasible solution to suply loads of magnitudes that do not justify economically the construction of new substations. This paper presents a fault location algorithm for multiple terminals transmission lines - two and three terminals. The location method is based on the use of voltage and current fundamental phasors, as well as the representation of the line through its series impedance. The wavelet transform is an effective mathematical tool in signals analysis with discontinuities and, therefore, is used to synchronize voltage and current data. The Fourier transform is another tool used in this work for extract voltage and current fundamental phasors. Tests to validate the location algorithm applicability used data from faulty signals simulated in ATP (Alternative Transients Program) as well as real data obtained from oscillographic recorders installed on CHESF s lines.