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Utilização de linhas de transmissão semelhantes no ensaio de energização de um tronco com pouco mais de meio comprimento de onda / Utilization of similar transmission lines on energization test of a trunk with a little more than a half-wavelengthGomes, Elson Costa, 1986- 19 August 2018 (has links)
Orientador: Maria Cristina Dias Tavares / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Elétrica e de Computação / Made available in DSpace on 2018-08-19T21:10:18Z (GMT). No. of bitstreams: 1
Gomes_ElsonCosta_M.pdf: 4986234 bytes, checksum: 3e2729d9cbec861f21c958f84db0b17e (MD5)
Previous issue date: 2012 / Resumo: O transporte de grandes blocos de energia elétrica através de longas distâncias que variam de 2500 a 3000 km impõe a utilização de soluções mais adequadas baseadas em linhas de transmissão não convencionais. Uma alternativa em corrente alternada (CA) é a linha com pouco mais de meio comprimento de onda, que para o caso brasileiro, cuja frequência industrial é 60 Hz, apresenta comprimento físico de aproximadamente 2600 km. Por não existir no mundo um sistema similar em operação, foi proposta a realização da manobra de energização de um Elo CA Teste composto pela conexão em série de três interligações do sistema brasileiro que têm características elétricas semelhantes e que juntas formam um tronco de 2600 km. O presente trabalho visa avaliar a adequação de se utilizar um tronco formado por linhas semelhantes para representar um tronco de um pouco mais de meio comprimento de onda durante a manobra de energização da linha em vazio. Através de análise da resposta dos parâmetros das linhas no domínio da frequência e de simulações no domínio do tempo realizadas com os programas computacionais ATP e PSCAD/EMTDC para a avaliação de transitórios, observou-se que o uso do tronco proposto para o ensaio de energização é adequado e foram determinados valores limites para as diferenças entre características elétricas das linhas que podem compor sistemas com pouco mais de meio comprimento de onda, fornecendo importantes subsídios para a possível realização do referido ensaio em outros locais do mundo / Abstract: The transportation of large blocks of energy through very long distances between 2500 and 3000 km requires an extensive research for the best solutions based on non-conventional transmission systems. A very interesting alternative is the AC transmission with a little more than half-wavelength, which corresponds to a transmission line of 2600 km in systems like the Brazilian, with 60 Hz fundamental frequency. However, as there is no similar system in operation around the world, it was proposed a realization of the energization of an AC-Link Test composed of three interconnection trunks that have similar electrical characteristics that together can form a trunk of 2600 km. In this work it is evaluated the adequacy of using a trunk formed by similar lines to represent a line of a little more than a half wave-length during an energization maneuver. The response of AC-Link Test parameters in frequency domain and time domains simulations performed with the computer programs ATP and PSCAD/EMTDC, to evaluate transient response, showed that the proposed use of the trunk for the energization is appropriate. It was also identified limits for the differences between electrical characteristics of the lines that can form a trunk with a little more than a half-wavelength, contributing to the possible realization of the same test in other parts of the world / Mestrado / Energia Eletrica / Mestre em Engenharia Elétrica
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BPL modem / BPL modemChromý, David January 2020 (has links)
This work deals with the issue of PLC with a focus on BPL technology (Broadbandover-power lines), which is explained in the theoretical part. The work describes in detailthe main components for PCB design with manufacturing and mounting process. Fur-thermore, the thesis provides instructions on how to establish communication betweenBPL modems and a description of individual functions. In conclusion, the procedureof measuring the noise intensity in the 230 V power line is described with the results.The output of the diploma thesis is the selection of components and the implementationof printed circuit boards for two BPL modems. These modems allow to measure SNR(signal to noise ratio) at physical speed.
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Automatisering av markbedömning för nya kraftledningar med GIS : Metodutveckling med MKA / Automated land use suitability assessment for power lines in GIS : Method Development with MCABondesson, Anton, Wessman, Lisa January 2022 (has links)
The Swedish power grid is facing challenging times to cope with the transition to green renewable energy and to ensure safe and sustainable transportation through the country. The need to upkeep with maintenance and reconstruction as well as construction of new power lines requires planning and overhead power lines require extensive areas of safe zones below the power lines. In the planning stage of these streaks there are multiple areas of interest that require careful consideration and therefore evaluations of the area of interest are necessary.This bachelor thesis aims to develop a prototype for an automated tool in the initial suite selection of possible streaks for new power lines. The project is done in collaboration with NEKTAB who want to investigate the potential of developing their own tool for standardized evaluations of suite selections and to reduce workload. By utilizing multicriteria analysis (MCA) and geographical information systems (GIS), two software packages are used and compared, i.e. FME and ArcGIS Pro. Prototypes are developed from a reference project Eon is working on alongside NEKTAB. A sophisticated weighting system to evaluate areas of interest against each other is designed using the weighing method SWING and MCA-method weighted linear combination (WLC). The two prototypes from the software are compared through grid comparisons and by utilizing a predefined classification. The results show limited differences between the software though greater disparity when it comes to stability and the capability to manage larger amounts of data.The conclusions of the development and comparisons of the software and results show that both are capable in managing large amounts of data and accomplish the task, though the stability and functions are better within FME thus being more suitable for further optimization. Further development is required as the prototypes still do not manage all the requested features. Further developments are also required with the weighing system to meet expectations on a larger scale with more local and national areas of interest. / Det svenska elnätet står inför en enorm utmaning för att klara omställningen till grön energi och för att säkert transportera elen genom landet. Många kraftledningar är i behov av underhåll, ombyggnad och nybyggnation och när de gäller nybyggnation kräver luftledningar breda ledningsgator som tar stora arealer i anspråk. Det finns dock ett stort antal intressen som riskerar hamna i konflikt med etablering av kraftledningar och därför krävs en undersökning av aktuella markområden.Detta examensarbete syftar till att ta fram prototyper på automatiserade verktyg för ett första urval av möjliga etableringsområden. Arbetet utförs tillsammans med företaget NEKTAB som vill undersöka förutsättningarna för att utveckla ett eget verktyg för att standardisera urvalet och korta ned arbetstiden, detta genomförs med multikriterieanalys (MKA) och geografiska informationssystem (GIS). I arbetet med att ta fram automatiska modeller har två programvaror jämförts, ArcGIS Pro och FME, utifrån ett referensprojekt med Eon. För att uppnå detta har en viktningsmodell tagits fram som implementeras med MKA metoden weitghted linear combination (WLC). De två prototyperna jämförs genom celljämförelser utifrån en definierad klassning, framtagen utifrån referensprojektet och resultatet av jämförelsen visar på små skillnader mellan FME och ArcGIS Pro, men större skillnader i programmens stabilitet och hur de hanterar större datamängder.Slutsatser som dras är att både FME och ArcGIS Pro är användbara kandidater för ett generaliserat och utvecklat verktyg men att stabiliteten är bättre hos FME och därför mer lämplig att använda. Fortsatt arbete kommer krävas i den fortsatta utvecklingen av prototyperna tillsammans med en vidareutveckling av viktningen för att säkerställa att denna fungerar på större skala, med fler lokala och nationella intresseområden.
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Nattfjärilar (Macrolepidoptera) längs smala kraftledningsgator omgiven av olika successionsstadier av boreal skog / Abundance and species richness of moths (Macrolepidoptera) along narrow power line corridors surrounded by different successional stages of boreal forestUlvrike, Villemo January 2022 (has links)
Ett av de primära hoten mot biologisk mångfald och populationsnedgångar är utvecklingen av de moderna jord- och skogsbruket, där intensifierad markanvändning vidare har lett till förlust av lämpliga livsmiljöer för många organismgrupper, inklusive insekter. Nattfjärilar anses vara en indikatorgrupp för miljöförändringar och deras nedgång har dokumenterats i flera europeiska länder. Utvecklingen av infrastruktur som ytterligare bidrar till markanvändningen, till exempel kraftledningsgator, har fått ett ökat intresse att utforskas ur ett naturvårdsperspektiv. Studier har visat att insektsgrupper som till exempel vilda bin och dagfjärilar potentiellt kan använda kraftledningsgator som en möjlig livsmiljö, men liknande studier är bristfälliga för nattfjärilar. Kraftledningsgator löper genom landskapets varierande naturtyper och korsar därmed skogsbestånd påverkade av skogsbruket. Denna studie undersökte abundans och artrikedom av nattaktiva storfjärilar (Macrolepidoptera) i norra Sverige längs smala kraftledningsgator omgiven av olika successionsstadier av boreal skog och skog opåverkade av kraftledningsgator som kontroll. Samtidigt undersöktes effekter av säsong och nattlig temperatur på förekomsten av nattfjärilar i studien. Nattfjärilar samlades in genom ljusfångst under juli och augusti 2022. Vidare kunde ingen signifikant skillnad påvisas i artrikedom eller abundans av nattfjärilar mellan kraftledningsgator omgiven av olika tillväxtstadier av skogsbestånd och kontrollgruppen. Däremot observerades en varierad artsammansättning i vardera habitattyp. Resultatet kan vagt antyda att nattfjärilar i varierande skogsbestånd möjligtvis kan nyttja de smala kraftledningsgator som löper genom områdena om ledningsgatan innehar en gynnsam miljö med viktiga värdväxter. Men större studier behövs för att undersöka kraftledningsgator som livsmiljö och eventuella effekter av angränsande omgivning. Utöver påvisades skillnader i abundans och artrikedom av nattfjärilar mellan perioder (juli och augusti), samt positiva korrelationer mellan fångstfrekvensen av nattfjärilar och högre temperatur under nätterna vid ljusfångst. Resultaten indikerar att säsong och temperatur är faktorer som bör tas i beaktning vid studier av nattfjärilar för att få mer tillförlitliga provtagningar i ett habitat. Nationella långtidsstudier av nattfjärilar saknas och en ökad kunskap om status och trender av populationer är nödvändigt. Naturvårdsåtgärder för infrastrukturbiotoper behöver en samverkan mellan aktörer och ett helhetsperspektiv där omgivande landskap tas i beaktning. Fler och större studier behövs för att utvärdera kraftledningsgators potential i förhållande till deras negativa effekter på biodiversitet och fler studier är nödvändiga för att undersöka om kraftledningsgators arealer kan optimeras i förvaltning och användas av viktiga hotade insektsgrupper, som till exempel nattfjärilar. / One of the primary threats to biodiversity and population declines is intensified agriculture and forestry management. Intense land use leads to loss of suitable habitats for many groups of organisms, including insects. Moths are considered an indicator group for environmental changes and their decline has been documented in several European countries. Furthermore, development of infrastructure, power line corridors for example, also contributes to land use. However, studies have indicated that insects such as wild bees and diurnal butterflies can potentially use power line corridors, but studies are lacking if this applies to moths. Power line corridors run through the landscape and their adjacent environment are thus very varied. This study investigates the abundance and species richness of moths (Macrolepidoptera) in northern Sweden, along narrow power line corridors surrounded by different successional stages of boreal forest, compared to forests unaffected by power lines. Mid- and late summer season and temperature effects were also investigated. Moths were collected in july and august 2022 by sampling at night with light traps. No significant difference could be demonstrated between power line corridors surrounded by different forest types and the control group, for either abundance or species richness. Even though there were no difference in species richness between sites, the species composition of moths in each habitat varied. The result may indicate that moths in different forest types potentially can use the narrow power line corridors that run through the area, if the local environment is favorable and vital host plants are present, but more studies are needed to investigate power lines as novel habitats and possible effects of the surrounding environment. Furthermore, abundance and species richness of moths were greater in late summer, and postively corellated with higher temperatures at nights, which indicates that these factors should be taken into account when sampling moths to survey and evaluate populations in a site. National long-term studies of moths are lacking and an increased knowledge of status and trends of moth communities is needed. From a conservation point-of-view, the areas beneath power lines should be managed and optimized with a landscape perspective in consideration. More studies are necessary to evaluate power line corridors possibility to act as potential novel habitats for important groups of organisms that are declining, for example insects such as moths.
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Analýza vyvedení elektrického výkonu v městské zástavbě / Analysis ofelectrical output from the power plat working in the middle of townHrubý, Radek January 2012 (has links)
The work focuses on outlet of the electrical power from power plants operating in urban areas. After a short analysis of the general possibility of leading out electric power from power plants of various types, thesis continues to describe of outlet electrical power from PPC Červený Mlýn. Subsequently, are calculated short-circuit conditions in the main switching station. It follows an analysis of power lines. The last part dealt with the issue of reliability of sources in connection with random transition processes in the electrical network and the light of the operational reliability of electrical power equipment.
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Planejamento de sistemas de transmissão em área com fonte de geração intermitente, apoiado no uso de tecnologias avançadas. / Planning of transmission systems in an area with an intermittent generation source, based on the use of advanced technologies.Silveira, Patrícia Oliveira da 02 May 2017 (has links)
O Brasil é um país de dimensões continentais, onde existe uma considerável distância entre a geração e os principais centros de consumo. Dessa forma, o estudo e desenvolvimento de novas tecnologias de transmissão a longas distâncias é de fundamental importância para o desenvolvimento do país. A solução mais utilizada atualmente é a transmissão em corrente alternada. Entretanto a transmissão em corrente continua também é uma solução viável para longas distâncias. O sistema brasileiro é composto principalmente por linhas 500 kV em corrente alternada (também há 230; 345; 440 e 750 kV), bem como em corrente continua (em ±600 e ±800 kV). O presente estudo apresenta uma solução de transmissão em corrente alternada por linhas de 1000 kV, que se mostrou mais econômico na transmissão de potências superiores a 3.500 MW e distâncias de 1400km. Nos próximos anos, a geração de energia elétrica no Brasil será expandida de forma significativa, ocorrerá um aumento principalmente na geração de energia eólica e solar, localizadas em sua maioria na região Nordeste do país. Esse aumento na geração exigirá a transmissão de grandes blocos de energia elétrica por distâncias significativas, devido à falta de proximidade entre a geração e os principais centros consumidores, que estão localizados no Sudeste. Neste estudo, serão mostradas as etapas de definição de condutor economicamente mais adequado e projeto da geometria da torre. Com base nos dados obtidos, será feita a avaliação do desempenho da linha 1000 kV, durante a operação normal de fluxo de carga, curtos-circuitos e estabilidade. / Brazil, a country of continental proportions, have significant distance between the power generation centers and the main consumer centers. In such way, the study and development of new transmission technologies over long distances is of fundamental importance for the development of the country. Nowadays, the most commonly used solution is alternating current transmission. However, direct current transmission is also a viable solution for long distances. The Brazilian system mainly consists of 500 kV alternating current lines (along with 230, 345, 440 and 750 kV) and direct current lines (± 600 and ± 800 kV). This study provides a solution for transmission in alternating current by lines of 1000 kV, which proved to be more economical in power transmission over 3,500 MW and distances beyond 1400km. In the coming years, the electric power generation in Brazil will expand significantly; a boost will take place mainly in wind and solar power generation, located mostly in the Northeast of the country. This generation expansion will require transmission of large blocks of electric power over considerable distances, due to the lack of proximity between generation sites and main consumer centers located in the Southeast. This study will show the setting stages of the most economically applicable conductor and tower geometry design. Based on the data obtained, the performance of the 1000 kV line will be evaluated during the regular load flow operation, short circuits and stability.
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Planejamento de sistemas de transmissão em área com fonte de geração intermitente, apoiado no uso de tecnologias avançadas. / Planning of transmission systems in an area with an intermittent generation source, based on the use of advanced technologies.Patrícia Oliveira da Silveira 02 May 2017 (has links)
O Brasil é um país de dimensões continentais, onde existe uma considerável distância entre a geração e os principais centros de consumo. Dessa forma, o estudo e desenvolvimento de novas tecnologias de transmissão a longas distâncias é de fundamental importância para o desenvolvimento do país. A solução mais utilizada atualmente é a transmissão em corrente alternada. Entretanto a transmissão em corrente continua também é uma solução viável para longas distâncias. O sistema brasileiro é composto principalmente por linhas 500 kV em corrente alternada (também há 230; 345; 440 e 750 kV), bem como em corrente continua (em ±600 e ±800 kV). O presente estudo apresenta uma solução de transmissão em corrente alternada por linhas de 1000 kV, que se mostrou mais econômico na transmissão de potências superiores a 3.500 MW e distâncias de 1400km. Nos próximos anos, a geração de energia elétrica no Brasil será expandida de forma significativa, ocorrerá um aumento principalmente na geração de energia eólica e solar, localizadas em sua maioria na região Nordeste do país. Esse aumento na geração exigirá a transmissão de grandes blocos de energia elétrica por distâncias significativas, devido à falta de proximidade entre a geração e os principais centros consumidores, que estão localizados no Sudeste. Neste estudo, serão mostradas as etapas de definição de condutor economicamente mais adequado e projeto da geometria da torre. Com base nos dados obtidos, será feita a avaliação do desempenho da linha 1000 kV, durante a operação normal de fluxo de carga, curtos-circuitos e estabilidade. / Brazil, a country of continental proportions, have significant distance between the power generation centers and the main consumer centers. In such way, the study and development of new transmission technologies over long distances is of fundamental importance for the development of the country. Nowadays, the most commonly used solution is alternating current transmission. However, direct current transmission is also a viable solution for long distances. The Brazilian system mainly consists of 500 kV alternating current lines (along with 230, 345, 440 and 750 kV) and direct current lines (± 600 and ± 800 kV). This study provides a solution for transmission in alternating current by lines of 1000 kV, which proved to be more economical in power transmission over 3,500 MW and distances beyond 1400km. In the coming years, the electric power generation in Brazil will expand significantly; a boost will take place mainly in wind and solar power generation, located mostly in the Northeast of the country. This generation expansion will require transmission of large blocks of electric power over considerable distances, due to the lack of proximity between generation sites and main consumer centers located in the Southeast. This study will show the setting stages of the most economically applicable conductor and tower geometry design. Based on the data obtained, the performance of the 1000 kV line will be evaluated during the regular load flow operation, short circuits and stability.
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Συμβολή στην ανάλυση του ηλεκτρικού και του μαγνητικού πεδίου στο περιβάλλον εναερίων γραμμών ηλεκτρικής ενέργειαςΤζινευράκης, Αντώνιος 22 December 2009 (has links)
Η παρούσα διδακτορική διατριβή αποτελεί μια συμβολή στην ανάλυση του ηλεκτρικού πεδίου στο περιβάλλον εναέριων γραμμών απλού και διπλού κυκλώματος. Αναπτύσσονται αναλυτικές σχέσεις για τον ακριβή υπολογισμό της έντασης του ηλεκτρικού πεδίου καθώς και απλούστερες προσεγγιστικές σχέσεις. Η προτεινόμενη μέθοδος υπολογισμού προέκυψε από τον συνδυασμό της ανάλυσης των φορτίων των αγωγών σε συμμετρικές συνιστώσες, της περιγραφής της έντασης του ηλεκτρικού πεδίου με διπλούς μιγαδικούς αριθμούς και της χρήσης του αναπτύγματος πολυπόλων για την έκφραση της έντασης του ηλεκτρικού πεδίου. Με τους διπλούς μιγαδικούς αριθμούς επιτυγχάνεται η παράσταση με μιγαδικούς αριθμούς τόσο των χρονικά ημιτονοειδώς μεταβαλλόμενων μεγεθών (τάσεων και φορτίων) όσο και των γεωμετρικών αποστάσεων. Το ανάπτυγμα πολυπόλων είναι μια σειρά απείρων όρων, όπου ο κάθε επόμενος όρος είναι αντιστρόφως ανάλογος της αυξανόμενης δύναμης της απόστασης. Αναπτύσσονται επίσης ακριβείς αναλυτικές σχέσεις, καθώς και απλούστερες προσεγγιστικές σχέσεις, για τον υπολογισμό της μαγνητικής επαγωγής γραμμών διπλού κυκλώματος. Για την ανάπτυξη των σχέσεων αυτών συνδυάζεται η χρήση των διπλών μιγαδικών αριθμών με το ανάπτυγμα πολυπόλων για την έκφραση της μαγνητικής επαγωγής. / This thesis is a contribution to the analysis of the electric field in the vicinity of single-circuit and double-circuit overhead power lines. Analytical formulas are developed for the accurate calculation of the intensity of the electric field as well as simpler approximate formulas. The proposed calculation method has arisen from the combination of the analysis of the conductors’ charges in their symmetrical components, the description of the intensity of the electric field using double complex numbers and the use of multipole expansions to express the intensity of the electric field. The use of double complex numbers allows the simultaneous representation of sinusoidal varying quantities (voltages and charges) and geometrical distances with complex numbers. The multipole expansion is a series of infinite terms, where each term is inversely proportional to an increasing power of the distance. Accurate analytical formulas are also developed as well as simpler approximate formulas for the calculation of the magnetic flux density produced by double-circuit lines. For the development of those formulas the use of double complex numbers is combined with the multipole expansion to express the magnetic flux density.
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Soustavná elektrizace venkova na příkladu vybraných jihočeských obcí. / Systematic Electrification of the Countryside on the Example of South Bohemian MunicipalitiesTýle, Prokop January 2022 (has links)
This diploma thesis focuses on the systematic electrification - i.e. the production and distribution of electric power - in the era of the First Czechoslovak Republic. Based on several important acts and regulations, the author analyses and shortly introduces the development of the law system (connected with this phenomenon). He illustrates some fundamental aspects of the process of electrification, such as the financial participation of the state, the electric utility companies or the subsidization of the countryside electrification. As an example, the author then presents, the regional autonomy (nejsem si jistá, co tohle znamená, ale protože je to hodně specifikovaný, dala bych určitý člen) of Tábor in the South Bohemia District. Based on this, he aims to introduce the process of this long-term economic and social phenomenon in interwar Czechoslovakia. The author uses mainly historical administrative sources, published sources, and regional press, to show the development of electrification in the area with small rural municipalities and its agriculture-based economy. He furthermore puts the researched topic of the systematic electrification into the context of the wider region of the South Bohemia focusing on the activities of two leading south-bohemian electrotechnical companies: Jihočeské...
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