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