ANÁLISE DAS DISTORÇÕES HARMÔNICAS – ESTUDO DE CASO DE UM SISTEMA INDUSTRIAL DOUGLAS ÂNGELO TEIXEIRA Programa de Pós-Graduação de Engenharia Elétrica da UNIVERSIDADE FEDERAL DE MINAS GERAIS BRASIL

ANÁLISE DAS DISTORÇÕES HARMÔNICAS – ESTUDO DE CASO DE UM SISTEMA INDUSTRIAL DOUGLAS
Autor: ÂNGELO TEIXEIRA
Orientador: PORFÍRIO CABALEIRO
 Dissertação de Mestrado apresentada ao Programa de Pós-Graduação de Engenharia Elétrica da UFMG, como parte dos requisitos para obtenção do Título de Mestre em Engenharia Elétrica. PPGEE – UFMG
Novembro de 2009
 RESUMO
 O trabalho apresenta uma revisão geral sobre os indicadores relacionados a harmônicos, equipamentos que geram estas distorções e equipamentos sensíveis a estes distúrbios na rede elétrica. São utilizados alguns documento referentes ao assunto de distorções harmônicas são tais como: as recomendações do IEEE 519-1992, os “Procedimentos de Rede do ONS” no seu submódulo 2.8 e o conjunto de normas IEC série 61000. Os filtros harmônicos são utilizados para reduzir as distorções causadas por equipamentos com comportamento não-linear. O projeto destes filtros, as definições existentes e a avaliação de cada tipo de filtro são apresentados juntamente com os critérios práticos de seleção. As medições no sistema elétrico de um grande consumidor industrial são realizadas com o intuito de identificar injeções harmônicas desta empresa na rede elétrica da concessionária. Os medidores de energia são instalados no secundário dos principais transformadores da empresa e na entrada da subestação para obter estes dados. Após o trabalho de campo de coleta de dados, o sistema elétrico é modelado no Simulink/Matlab. A simulação incorpora um modelo simplificado da rede elétrica incluindo a alimentação proveniente da concessionária, as linhas de transmissão e distribuição, os principais transformadores, as cargas e os harmônicos presentes em cada um dos alimentadores. A partir da análise da situação da empresa busca-se propor melhorias para que a mesma possa operar sem prejudicar o sistema ao qual está conectada e atender os limites das distorções harmônicas de tensão presentes no submódulo 2.8 do Operador Nacional do Sistema e a melhoria do fator de potência.
FULL THESIS
https://copy.com/T3HsP0zKpJ7ZVKax

Cálculo dos transformadores P. Tikhomirov

 Cálculo dos transformadores    Ano: 1986 Autor: P. Tikhomirov 
Categoria: Engenharia Elétrica
 Idioma: Russo
 Descrição: Este livro fornece informações básicas sobre o cálculo teoria de transformadores são uma metodologia detalhada de projetar transformadores de potência com planar e sistemas magnéticos eseciais de aço elétrico laminado a frio com enrolamentos de cobre e fio de alumínio e dá exemplos práticos de cálculo. O livro contém as informações necessárias para o cálculo de projeto de sistemas magnéticos, bobinas, sistemas de refrigeração de transformadores de potência modernos e materiais de referência. O livro é destinado a estudantes de energia elétrica e escolas de ensino médio como uma ferramenta de ensino no curso e grau projetar e estudar o curso "Desenho de Máquinas Elétricas", e também pode ser útil para engenheiros e técnicos que trabalham na área de projeto, fabricação, operação e manutenção de transformadores
LINK
https://copy.com/yDgndtcEYJOUbZzA

ANÁLISE DA VIABILIDADE FINANCEIRA DA UTILIZAÇÃO DE TRANSFORMADORES DE NÚCLEO AMORFO ESTUDO DE CASO APLICADO AO PROJETO DE SUBESTAÇÃO AÉREA DE 75 KVA Diego Falchi Teixeira Barros Universidade Federal do Ceará Centro de Tecnologia Curso de Graduação em Engenharia Elétrica

ANÁLISE DA VIABILIDADE FINANCEIRA DA UTILIZAÇÃO DE
TRANSFORMADORES DE NÚCLEO AMORFO – ESTUDO DE CASO
APLICADO AO PROJETO DE SUBESTAÇÃO AÉREA DE 75 KVA
Monografia submetida à Universidade Federal
do Ceará como parte dos requisitos para
obtenção do título de Graduado em Engenharia
Elétrica.
Orientador: Prof. MSc. Carlos Gustavo Castelo Branco.
LINK
http://www.dee.ufc.br/anexos/TCCs/2011.1/DIEGO%20FALCHI%20TEIXEIRA%20BARROS.pdf

AMPLIAÇÃO E MELHORIA NA SUBESTAÇÃO PICI II - CHESF PELA IMPLANTAÇÃO DO 4º TRANSFORMADOR DE POTÊNCIA 100 MVA 230 kV / 69 kV ANDRÉ LUIZ DE BRITO UNIVERSIDADE FEDERAL DO CEARÁ CENTRO DE TECNOLOGIA DEPARTAMENTO DE ENGENHARIA ELÉTRICA CURSO DE GRADUAÇÃO EM ENGENHARIA ELÉTRICA

SISTEMA FOTOVOLTAICO INTERLIGADO À REDE ELÉTRICA COM
CONTROLE DE FLUXO DE POTÊNCIA FEITO POR UM CONVERSOR CC-CC
ISOLADO
SAMUEL SOARES QUEIROZ
Monografia apresentada para obtenção dos
créditos da disciplina Trabalho de Conclusão
de Curso do Centro de Tecnologia da
Universidade Federal do Ceará, como requisito
parcial à obtenção do título de Graduado em
Engenharia Elétrica. Área de concentração:
Eletrônica de Potência e Acionamentos.
LINK
http://www.dee.ufc.br/anexos/TCCs/2014.1/SAMUEL%20SOARES%20QUEIROZ.pdf

APLICATIVO ANDROID PARA MONITORAMENTO TERMOELÉTRICO E DIAGNÓSTICO DE TRANSFORMADORES SILAS ALYSSON SOUZA TIBÚRCIO UNIVERSIDADE FEDERAL DO CEARÁ CENTRO DE TECNOLOGIA DEPARTAMENTO DE ENGENHARIA ELÉTRICA

APLICATIVO ANDROID PARA MONITORAMENTO TERMOELÉTRICO E DIAGNÓSTICO DE TRANSFORMADORES
SILAS ALYSSON SOUZA TIBÚRCIO
Monografia apresentada ao Curso de Engenharia Elétrica do Departamento de Engenharia Elétrica da Universidade Federal do Ceará, como requisito parcial à obtenção do Título de Bacharel em Engenharia Elétrica.
Orientador: Prof. Dr. Artur Plínio de Souza Braga.
Coorientador: Prof. Dr. Otacílio da Mota Almeida.
FORTALEZA
2013
LINK
http://www.dee.ufc.br/anexos/TCCs/2013.2/SILAS%20ALYSSON%20SOUZA%20TIB%C3%9ARCIO.pdf

The Study of 3-Phase DC-AC Inverter for a Bi-Modal Photovoltaic Power Conditioning System Seungdae Yang Department of Embedded Software Graduate School, Kwangwoon University Seoul, Korea

ABSTRACT
The Study of 3-Phase DC-AC Inverter for a Bi-Modal Photovoltaic Power Conditioning System Seungdae Yang
 Department of Embedded Software Graduate School, Kwangwoon University Seoul, Korea Supervised by professor Juyeop Choi

 This paper designs the 3-phase DC-AC inverter controller for a bi-modal PV PCS which transmit a power bi-directionally. Also it proposes a new compensation algorithm for a distorted grid current caused by a distorted grid voltage. Simulation and experiment are used to validate the proposed bi-directional inverter controller design and compensation algorithm. Furthermore, it analyzes the Euro efficiency of the inverter by calculating the sum of each weighted loss for an inductor and PWM circuit. At first, in order to run inverter bi-directionally, inverter must control both DC link voltage and also inverter output current. Therefore, the control block has a voltage controller to control DC link voltage at outer loop and a current controller to control inverter output current at inner loop. For calculating phase of AC current, this paper provides the optimum gain of PLL(Phase Locked Loop) for voltage controller and current controller. Simulation and experiment are also used to validate the proposed bi-directional inverter controller design. Because of connected nonlinear or single phase load at PCC(Point of Common Coupling), grid voltage usually has small distortion and unbalance. Distorted current by nonlinear load caused voltage distortion at PCC. Also unbalanced current by single phase load caused voltage unbalance at PCC. Finally, unbalanced and distorted voltage of grid voltage makes oscillated DC link voltage causing grid current distortion and also worsening grid voltage distortion. So this paper proposes simple compensation algorithm for distorted grid current in unbalanced and distorted grid voltage environment. The proposed compensation algorithm provides robust PLL using positive sequence for calculating grid voltage and feedforward calculated distortion voltage to inverter output reference. It is validated PSIM simulation and experiment with inverter stack and DSP control circuits, NF 3-phase power supply and My Way PV simulator.

AVALIAÇÃO EXPERIMENTAL DE LUMINÁRIAS EMPREGANDO LEDs ORIENTADAS À ILUMINAÇÃO PÚBLICA FERNANDO JOSÉ NOGUEIRA Dissertação de Mestrado Faculdade de Engenharia da Universidade Federal de Juiz de Fora BRASIL

AVALIAÇÃO EXPERIMENTAL DE LUMINÁRIAS EMPREGANDO LEDs ORIENTADAS À ILUMINAÇÃO PÚBLICA

FERNANDO JOSÉ NOGUEIRA

Dissertação de Mestrado apresentado ao Programa de Pós-Graduação em Engenharia Elétrica da Faculdade de Engenharia da Universidade Federal de Juiz de Fora-BRASIL
como requisito para a obtenção do título de Mestre em Engenharia Elétrica, área de Concentração em Sistemas Eletrônicos.
Orientador: Prof. Henrique Antônio Carvalho Braga Dr. Eng.-2013


RESUMO Este trabalho tem como objeto principal a avaliação experimental de diodos emissores de luz (ou LEDs, do inglês Light Emitting Diodes) quando empregados em luminárias comerciais destinadas aos sistemas de iluminação pública. São apresentados os aspectos gerais da iluminação pública no Brasil, os principais componentes empregados e uma discussão sobre a adoção da tecnologia LED na iluminação de exteriores. Também são abordados os conceitos básicos de fotometria clássica e da fotometria adaptada para baixos níveis de luminância, que leva em consideração a resposta dinâmica visual do olho humano. Para efeito comparativo, o trabalho também inclui uma revisão das principais fontes de luz brancas orientadas à iluminação pública, e. g. lâmpada de vapor metálico, lâmpada de vapor de mercúrio e, mais recentemente, os LEDs. Tal estudo ampara-se em ensaios de laboratório e em campo tomando como base a lâmpada de vapor de sódio em alta pressão, a mais utilizada atualmente no segmento de iluminação de vias públicas. Algumas normativas referentes à aplicação de LEDs em iluminação pública são discutidas e, a partir das recomendações existentes nas normas NBR 16026 e NBR IEC 61347-2-13, são realizados ensaios de pré-conformidade em amostras comerciais de luminárias LED orientadas à iluminação pública do mercado nacional. Além dos ensaios de pré-conformidade, são realizados ensaios de funcionamento das luminárias LED quando expostas a condições críticas de temperatura com o objetivo de se avaliar as mudanças elétricas e fotométricas que ocorrem nestas condições. É apresentada uma metodologia de projeto luminotécnico para instalação de luminárias LED em vias públicas baseando-se na norma de iluminação pública NBR 5101 (revisão 2012), e o acompanhamento do projeto piloto de iluminação pública empregando luminárias LED implantado no anel viário da faculdade de engenharia da Universidade Federal de Juiz de Fora. Durante nove meses foram coletados dados de características elétricas e fotométricas a fim de se averiguar o desempenho destas luminárias em campo. Por fim, foi feito um estudo comparativo entre o antigo sistema de iluminação com lâmpadas de vapor de sódio e o atual, empregando luminárias LED.

LINK1
https://www.google.com.br/url?sa=t&rct=j&q=&esrc=s&source=web&cd=2&cad=rja&uact=8&ved=0CCQQFjAB&url=http%3A%2F%2Fwww.ufjf.br%2Fppee%2Ffiles%2F2014%2F03%2FDisserta%25C3%25A7%25C3%25A3o-Fernando_Nogueira_vers%25C3%25A3o-corrigida_parahomologacao_CD.pdf&ei=FORlVJfANcSeNuTCgtAF&usg=AFQjCNHIlqRfZEAqY6R0b45UxKHk_jNbfw&bvm=bv.79142246,d.eXY

LINK2
https://copy.com/LgPjfxlPgwv2wVnU

Estratégia de controle para o conversor duplo boost operando em condução contínua aplicado na correção do fator de potência Autor: Martins, Alexandre Saccol Pós-Graduação em Engenharia Elétrica UNIVERSIDADE FEDERAL DE SANTA CATARINA

LINK1
https://repositorio.ufsc.br/xmlui/handle/123456789/111499
LINK2
https://repositorio.ufsc.br/xmlui/bitstream/handle/123456789/111499/103930.pdf?sequence=1&isAllowed=y

Making isolated renewable energy systems more reliable Luiz A. de S. Ribeiro , Osvaldo R. Saavedra, Shigeaki, José G. de Matos, Guilherme Bonan Electrical Energy Institute, Federal University of Maranhão, São Luís, MA, Brazil R&D Department, CP Eletrônica S.A, Porto Alegre, RS, Brazil

Introduction The supply of electricity to isolated communities in Brazil and other developing countries, in general, is still done in a precarious way, using diesel generators, which operate for 3e4 h a day [1,2]. This has happened mostly due to the high cost associated with the expansion of the conventional power grid to these communities. In some cases, technical and environmental constraints also have been factors that have prevented the full electrical service in these communities, especially those located on oceanic islands. For societies to have or attempt to maintain a sustainable development it is necessary a lot of effort in the discovery and use of renewable energy sources as well as in the increase of the efficiency in the processing of use these energy sources. In this aspect, the electric power generation based on solar photovoltaic and wind turbines technologies has been effective in distributed generation systems and also in standalone systems for supplying isolated communities [3,4]. In standalone systems, those solutions have been shown appropriate for areas of difficult access, dispersed, with environmental restrictions or with a population formed by low-income people, even when these adverse characteristics represent a difficulty for the sustainability of the designed generation system. Technical and operational troubles, and supply interruptions are difficult to be solved due to the non availability of technical assistance. The delay of remote assistance leads to long periods of lack of electrical service, causing loss of credibility in this kind of system [5,6]. Thus, to overcome these difficulties, isolated systems must be projected taking into account reliability, minimizing the dependence of maintenance and human intervention, mainly because it is expensive and quite often not available.
 LINK
https://sigaa.ufma.br/sigaa/verProducao?idProducao=145039&key=b1ef3085988018312827ca9d7bd09bba

Case study Large Hadron Collider CERN : Borri protects the particle accelerator

CASE STUDY UPS BORRY ITALY

CERN
Large Hadron Collider (LHC), the largest and most complex
scientific instrument ever built and the highest energy particle
accelerator in the world is protected by Borri solutions.
“Made in Italy protagonist at CERN: after the success of Italian
researchers in the discovery of the Higgs Boson the world’s largest
centres for scientific research chooses the Italian UPS Borri”

Borri Spa has provided both AC and DC. After a joint analysis with experts, CERN, has opted for a distributed power protection system, with equipment of various sizes that feed, in a redundant configuration, security systems and controlled shutdown of the accelerator. All UPS units are characterized by Borri technology sinusoidal absorption input (unity power factor and harmonic current distortion less than 3%) and they are derived from B8000FXS, B9000FXS and B9600FXS series with customisations that involved special painting and the system EPO (UPS emergency Power Off ). A specific redundancy configuration is also included, with three UPS in cascade, resulting in a system tolerant to the second failure.

The protection of the auxiliary 48 Vdc systems has been developed according to the requirements of CERN, from an Oil & Gas based rectifier, RTB.e series 100 A, with a custom redundancy system, providing a dual path for both the power supply of the loads, and the charging of the backup batteries. Even the battery cabinets have been develo- ped ad hoc, to meet the higher safety and maintainability requirements of the installation. Borri UPS also protect: Atlas project data center, with a system of three B9600FXS 500 kVA UPS in parallel with a 2000 A centralised static bypass switch and 4 minutes autonomy; LHC data center, with two B9600FXS 400 kVA UPS in parallel (dual feed redundant configuration) and 10 minutes autonomy Batteries are VRLA type (sealed lead acid) in all AC UPS systems and Ni-Cd type for DC UPS systems.

FULL PAPER
http://www.borri.it/public/docs/CS_EN_CERN-Borri-14.pdf

A Study on the Multi-level PV-PCS Using Cascade 3-Phase Transformer Kim, Ki-Seon ; Song, Sung-Geun ; Cho, Su-Eog ; Choi, Joon-Ho ; Kim, Kwang-Heon ; Park, Sung-Jun ;

A Study on the Multi-level PV-PCS Using Cascade 3-Phase Transformer
Kim, Ki-Seon ; Song, Sung-Geun ; Cho, Su-Eog ; Choi, Joon-Ho ; Kim, Kwang-Heon ; Park, Sung-Jun ;


Abstract
The study on the multi-level inverter has been increasingly progressing to reduce the switching loss and improve the THD of output current in photovoltaic inverter. Recently, the main topics of multi-level inverter are to reduce the number of devices maintaining the power quality. Therefore, the novel topology was proposed for these problem which is composed of the isolated H-bridge multi-level inverter using the three phase low frequency transformer. The proposed multi-level inverter may not be need for a independent DC power, diode and capacitor. Specially, It has a advantage in generating high voltage source. The proposed approach is verified through simulation and experiment.

LINK1
http://www.koreascience.or.kr/article/ArticleFullRecord.jsp?cn=DHJGII_2009_v58n12_2359

High power grid-connected PV PCS with power quality improvement and stand-alone operation KIM,JAE HYUNG GRADUATE SCHOOL SUNGKYUNKWAN UNIVERSITY PHOTOVOLTAIC SYSTEM ENGINEERING

High power grid-connected PV PCS with power quality improvement and stand-alone operation
KIM,JAE HYUNG
GRADUATE SCHOOL SUNGKYUNKWAN UNIVERSITY PHOTOVOLTAIC SYSTEM ENGINEERING

ABSTRACT

With the increase of power consumption, the limitation of fossil fuel and global warming, as power generation systems become superannuated, every country has faced several sorts of energy problems. Moreover, since power consumption has increased, not only reserve margin is decreased but also more power plants are required. However, the construction of power plants is restricted since those power facilities are closely related with environmental problems. Consequently, since the use of sensitive loads such as the latest IT products is increased, power quality issue is being magnified as a new controversy. In this research, the power quality improvement function applied to three-phase four-wire H-bridge type photovoltaic power generation system is proposed. When the photovoltaic power generation system is operated in grid-connected mode, grid current distorted by unbalanced load is improved, and the system is operated in stand-alone mode during power failure. Moreover, when the amount of solar radiation is low such as night time, the system is operated as a active power filter and improve the performance of the photovoltaic power generation system. The series dual loop with quasi-resonant proportional controller and 2ndorder deadbeat controller is applied to the system as a controller. Single phase PLL with phase synchronizing function, Goertzel stand-alone detection function with minimized non-detection area and Goertzel power quality control function are proposed. In order to verify the validity of the system performance, simulation and experiment with 100kw H-bridge type three-phase inverter are progressed.

A Study on Improving Efficiency of High-frequency Switching Hybrid Inverter Circuit in Grid-connected Photovoltaic Power Generation Heo, Chan-Yoo Department of Electrical Engineering Graduate School Soongsil University

ABSTRACT
A Study on Improving Efficiency of High-frequency Switching Hybrid Inverter Circuit in Grid-connected Photovoltaic Power Generation Heo, Chan-Yoo Department of Electrical Engineering Graduate School Soongsil University
Supervised by Professor Jeon, Hee-Jong
 The various problems of Energy pluralism by new and renewable energy technique development is in progress mainly from advanced countries due to recent global warming by environmental change and fossil energy resources depletion. And major area of fuel cell, photovoltaic and wind power generation are actively in progress from many types of new and renewable energy. Photovoltaic power system stores the direct current resource generated from photovoltaic module into battery, and converts this into alternating current to use. Photovoltaic power generation uses solar for its energy resource, which does not need fuel, and the equipment has long life since it has no moving parts or heat engine. Also, it is more convenient in operation and maintenance than other existing power generation methods. But, it has higher unit cost than existing power generating methods, and need wide area to install solar cell module to use certain amount of electric power since its energy density is scarce. In addition, it has weak point of close influence by environmental condition such as weather condition. All sections of the photovoltaic power system from raw material to the grid connection are important, but the photovoltaic power inverter, which relates the stable power to the grid or can supply powerto individual load, can be regarded as one of the most important section. The generated power is of no use if the inverter does not make regular output even though a lot of power is generated from the photovoltaic array. The criteria for evaluating the photovoltaic inverter's performance is the power conversion efficiency of the inverter. For domestic photovoltaic power system, the booster converter's efficiency is around 99[%], the inverter efficiency is around 94[%], and studies are in progress to improve inverter efficiency. The Grid connected inverters in photovoltaic PCS(Power Conditioning System) have different efficiency according to their switching methods. 3 Level PWM switching type circuit has half the frequency than the circuit composed of 2 Level PWM, and has improved efficiency because of less switching loss. In general, photovoltaic PCS mainly use IGBT components. But the hybrid circuit composed of MOSFET and IGBT components is considered to improve efficiency even more by improving reverse recovery time and loss by IGBT's tailing current. In this paper, it is intended to prove that the high-frequency switching inverter circuit with MOSFET has improved efficiency than 3 Level circuit with all IGBT components through simulation and 3[kW] PCS hardware.

Non-isolated Single Phase Uninterruptible Power Supply (UPS) System Muhammad Aamir Department of Electronics, Electrical, Control, and Instrumentation Engineering Hanyang University

ABSTRACT
In this thesis, a high performance single phase transformer-less online uninterruptible power supply (UPS) is proposed. The use of the bidirectional buck-boost converter with high conversion ratio not only reduces the number of batteries but also ensures a transformer-less system. The rectifier has capability of power factor correction and provides regulated DC link voltage whereas the inverter provides a regulated sinusoidal output voltage to the load. In order to control the transient effect, efficient control scheme is adopted in the system. The overall efficiency of the system is improved with significant reduction in size and weight of the system due to decrease number of batteries. Qualitative analysis and experimental results obtained with a 500VA prototype shows a normal efficiency of over 94% and an input power factor of over 99%.
LINK
https://copy.com/GDccLCWhNLzUqDJ0

Filtering Methods for DC Link Voltage Control of Common-neutral-type Transformerless Single-phase UPS KIM JI-SU DEPARTAMENT OF ELECTRICAL ENGINEERING GRADUATE SCHOOL KONKUK UNIVERSITY

ABSTRACT

UPS is largely divided into passive-standby, line-interactive, and double-conversion types. Commonly a double-conversion type is used at a site requiring a high reliability. These days, important factors of UPS are high efficiency, low input current distortion, high input power factor, small cabinet size and low price. In this thesis, a common-neutral type transformerless UPS is proposed. A proposed UPS is composed of PFC with 1-switch voltage doubler strategy, half-bridge inverter, separate battery charger and separate battery discharger. PFC with 1-switch voltage doubler strategy and half-bridge inverter are configured as commom-neutral type so that they can convert power without input and output transformer. Therefore input and output transformers can be removed, so the efficiency can be improved and cabinet size can be reduced. Also advantage of PFC with 1-switch voltage doubler strategy and half-bridge inverter is that they need a small number of switching devices so they can simplify driving circuitry and reduce the price. Advantage of separate battery charger and separate battery discharger is that they can make battery voltage lower than DC link voltage so they can reduce the quantity and cost of battery which is an important part of UPS. PI controller was used as voltage controller and current controller of PFC. In order to compensate imbalance of positive and negative DC link voltages, imbalance voltage PI controller was used. In order to compensate leading effect of input current, duty feedforward method was used. Several methods to eliminate 120Hz ripple component in DC voltage feedback were compared with each other. Moving Average resulted in better performance than other methods. Half-bridge was used as inverter circuit. In order to achieve stable static output voltage and improve dynamic characteristic multi-loop control method was used. Finally, the value of proposed UPS was confirmed in the method of simulation and experiment.