Cold Increases Service Life The Influence of the Operating Temperature on the Service Life and Reliability of Switching Power Supplies By Dipl.-Ing. (FH) Stefan Bergstein, Product Manager of EMTRON electronic GmbH-Bodo´s Power Systems

Cold Increases Service Life The Influence of the Operating Temperature on the Service Life and Reliability of Switching Power Supplies By Dipl.-Ing. (FH) Stefan Bergstein, Product Manager of EMTRON electronic GmbH-Bodo´s Power Systems

 The question of whether to use a transformer power supply or a switch-mode power supply is no longer dicussed today. In addition to superior technical properties, switched-mode power supplies impress with low costs, low weight and little space requirement. Certain requirements such as PFC (Power Factor Correction > 0.9 and sinusoidal mains current) can only be met with switched-mode power supplies. The question remains, what are the greatest influences on the service life and reliability of a switched-mode power supply?

LINK ORIGINAL:https://www.bodospower.com/
LINK PDF :
http://www.mediafire.com/file/iyexi5fa0e44yfk/COLD_INCRESEAS_SERVICE_LIFE_POWER_SUPPLY.pdf/file

Leading-Edge Power Modules for the New Era in Traction Converters By Vishal Jadhav, Wilhelm Rusche and Andre Lenze; Infineon Bodo´s Power Systems

Leading-Edge Power Modules for the New Era in Traction Converters Today, 55 percent of the world’s population live in urban areas, a proportion that is expected to increase to 68 percent by 2050 [1]. With this ever-increasing urban population, in combination with an increasing number of commuters on public transport, and a growing awareness of energy-efficiency and emission-free transportation systems, traction application is back in the limelight. A megatrend like urbanization provides a tailwind to improve, enhance and innovate today’s traction converters and components within its ecosystem. Power semiconductors, which are core components of traction converters enhancing their reliability, efficiency and longevity, are of utmost importance. By Vishal Jadhav, Wilhelm Rusche and Andre Lenze; Infineon.

BODO POWER SYSTEM MAY 2019
LINK: https://www.bodospower.com

Custom Transformers – Leakage Inductance Considerations By Dr. Ray Ridley, Ridley Engineering Inc. May 2019 Bodo´s Power Systems

Custom Transformers – Leakage
Inductance Considerations
By Dr. Ray Ridley, Ridley Engineering Inc.
May 2019 Bodo´s Power Systems
LINK: https://www.bodospower.com

Conception de convertisseurs électroniques de puissance à faible impact électromagnétique intégrant de nouvelles technologies d’interrupteurs à semi-conducteurs Présentée par Eliana RONDON-PINILLA Ecole Doctorale d’Electronique, Electrotechnique, Automatique-Université de Lyon

Conception de convertisseurs électroniques de puissance à faible impact électromagnétique intégrant de nouvelles technologies d’interrupteurs à semi-conducteurs Présentée par Eliana RONDON-PINILLA Ecole Doctorale d’Electronique, Electrotechnique, Automatique-Université de Lyon

 Résumé 
Actuellement, le développement de semiconducteurs et la demande croissante de convertisseurs en électronique de puissance dans les différents domaines de l’énergie électrique, notamment pour des applications dans l’aéronautique et les réseaux de transport et de distribution, imposent de nouvelles spécifications comme le fonctionnement à hautes fréquences de commutation, densités de puissance élevées, hautes températures et hauts rendements. Tout ceci contribue au fort développement des composants en SiC (Carbure de Silicium). Cependant, ces composants créent de nouvelles contraintes en Compatibilité Electromagnétique (CEM) à cause des conditions de haute fréquence de commutation et fortes vitesses de commutation (forts di/dt et dv/dt) en comparaison à d’autres composants conventionnels de l'électronique de puissance. Une étude des perturbations générées par les composants SiC est donc nécessaire. L'objectif de ce travail est de donner aux ingénieurs amenés à concevoir des convertisseurs une méthode capable de prédire les niveaux d'émissions conduites générées par un convertisseur électronique de puissance qui intègre des composants en SiC. La nouveauté du travail présenté dans cette thèse est l’intégration de différents modèles de type circuit pour tous les constituants d’un convertisseur (un hacheur série est pris comme exemple). Le modèle est valable pour une gamme de fréquences de 40Hz à 30MHz. Des approches de modélisation des parties passives du convertisseur sont présentées. Ces approches sont différentes selon que les composants modélisés soient disponibles ou à concevoir : elles sont basées sur des mesures pour la charge et les capacités ; elles sont basées sur des simulations prédictives pour routage du convertisseur. Le modèle complet du convertisseur (éléments passifs et actifs) est utilisé en simulation pour prédire les émissions conduites reçues dans le réseau stabilisateur d’impédance de ligne. Le modèle est capable de prédire l'impact de différents paramètres comme le routage, les paramètres de contrôle comme les différents rapports cycliques et les résistances de grille avec des résultats satisfaisants dans les domaines temporels et fréquentiels. Les résultats obtenus montrent que le modèle peut prédire les perturbations en mode conduit pour les différents cas jusqu'à une fréquence de 15MHz. Finalement, une étude paramétrique du convertisseur a été élaborée. Cette étude a permis de voir l’influence de la qualité des différents modèles comme les éléments parasites du routage, des composants passifs et actifs et d'identifier les éléments qui ont besoin d’un modèle précis pour avoir des résultats valides dans la prédiction des perturbations conduites.
LINK
https://www.theses.fr/2014ECDL0018.pdf

Conception d’un module d’électronique de puissance “Fail-to-short” pour application haute tension- Ilyas Dchar -THESE de DOCTORAT DE L’UNIVERSITE DE LYON

Conception d’un module d’électronique de puissance “Fail-to-short” pour application haute tension- Ilyas Dchar-  THESE de DOCTORAT DE L’UNIVERSITE DE LYON Designing a Power Module with Failure to Short Circuit Mode Capability for High Voltage Applications 

Abstract
The reliability and endurance of high power converters are paramount for future HVDC networks. Generally, module’s failure behavior can be classified as open-circuit failure and short-circuit failure. A module which fails to an open circuit is considered as fatal for applications requiring series connection. Especially, in some HVDC application, modules must be designed such that when a failure occurs, the failed module still able to carry the load current by the formation of a stable short circuit. Such operation is referred to as short circuit failure mode operation. Currently, all commercially available power modules which offer a short circuit failure mode use silicon semiconductors. The benefits of SiC semiconductors prompts today the manufacturers and researchers to carry out investigations to develop power modules with Fail-to-short-circuit capability based on SiC dies. This represents a real challenge to replace silicon power module for high voltage applications in the future. The work presented in this thesis aims to design a SiC power module with failure to short circuit failure mode capability. The first challenge of the research work is to define the energy leading to the failure of the SiC dies in order to define the activation range of the Fail-to-short mechanism. Then, we demonstrate the need of replacing the conventional interconnections (wire bonds) by massive contacts. Finally, an implementation is presented through a "half bridge" module with two MOSFETs.

Keywords : Press-Pack, Sandwich structure, conventional module, HVDC converter, Packaging, Failure, Short-circuit, Avalanche, Critical energy, Explosion, Stability, SiC.

LINK:
https://tel.archives-ouvertes.fr/tel-01784733/file/these.pdf

PROJETO E IMPLEMENTAÇÃO DE PLANTA FOTOVOLTAICA DE 65 KWP-PEDRO HENRIQUE ALBUQUERQUE GUIMARÃES-UNIVERSIDADE FEDERAL DO CEARÁ CENTRO DE TECNOLOGIA DEPARTAMENTO DE ENGENHARIA ELÉTRICA GRADUAÇÃO EM ENGENHARIA ELÉTRICA-BRASIL

PROJETO E IMPLEMENTAÇÃO DE PLANTA FOTOVOLTAICA DE 65 KWP-PEDRO HENRIQUE ALBUQUERQUE GUIMARÃES
UNIVERSIDADE FEDERAL DO CEARÁ CENTRO DE TECNOLOGIA DEPARTAMENTO DE ENGENHARIA ELÉTRICA GRADUAÇÃO EM ENGENHARIA ELÉTRICA
 Monografia apresentada ao Curso de Engenharia Elétrica do Departamento Elétrica da Universidade Federal do Ceará, como requisito parcial para a obtenção do título de Engenheiro Eletricista. Orientador: Prof. Dr. Paulo César Marques de Carvalho 

 RESUMO O presente trabalho visa apresentar as atividades realizadas durante as etapas de projeto e implementação de uma planta fotovoltaica de 65 kWp, localizada em região litorânea do nordeste brasileiro. Na fase de projeto, são explicitados os cálculos realizados para o dimensionamento do sistema e os critérios utilizados para a escolha de seus componentes. Optou-se, então, por painéis da Canadian Solar de 325 Wp e um inversor da ABB com potência nominal de 50 kW. Foi feito um levantamento topográfico com veículo aéreo não tripulado para estudo de sombreamento do local. Esse estudo foi elaborado com o auxílio do software de simulação PV*Sol, o que resultou na obtenção de parâmetros como fator de capacidade (FC) e previsão de geração. Os resultados foram de 19,92% de FC e previu-se uma produção de 113.429,5 kWh/ano. Na fase de implementação, são descritos todos os procedimentos realizados para a instalação do sistema. Estes foram divididos em etapas, a fim de ilustrar em ordem cronológica o trabalho desempenhado. Por fim, é feita a análise geral dos custos aproximados e prazos relacionados com a realização do projeto, além de enaltecer pontos positivos e pontuar melhorias nas atividades. Os custos finais excederam em 14,96% do valor de R$ 285.000,00 estimado previamente. Esse aumento se deu por dificuldades logísticas e gastos com obras de infraestrutura de segurança. A implantação foi concluída com sucesso após 4 meses e 20 dias do início do projeto.
LINK MONOGRAFIA COMPLETA:
http://www.repositorio.ufc.br/bitstream/riufc/35086/1/2018_tcc_phaguimaraes.pdf

CONCEPÇÃO E ANÁLISE DE UM SISTEMA DE ENERGIA PARA PICOSATÉLITES-DISSERTAÇÃO DE MESTRADO Everson Mattos-UNIVERSIDADE FEDERAL DE SANTA MARIA PROGRAMA DE PÓS-GRADUAÇÃO EM ENGENHARIA ELÉTRICA-SANTA MARIA-RS-BRASIL

RESUMO Dissertação de Mestrado Programa de Pós-Graduação em Engenharia Elétrica Universidade Federal de Santa Maria 
CONCEPÇÃO E ANÁLISE DE UM SISTEMA DE ENERGIA PARA PICOSATÉLITES
 AUTOR: EVERSON MATTOS
 ORIENTADOR: MÁRIO LÚCIO DA SILVA MARTINS
 CO-ORIENTADOR: RAFAEL CONCATTO BELTRAME
 Data e Local de Defesa: Santa Maria, RS, 27 de Abril de 2016

Em 1999 o padrão CubeSat foi criado para facilitar e reduzir os custos para lançamento de picosatélites, na sua maioria de cunho didático. Dadas às restrições de volume, peso e custo, os sistemas de energia devem primar pela eficiência e simplicidade. Os sistemas elétricos de potência para CubeSat podem ser divididos em dois tipos: os sistemas concentrados e os sistemas distribuídos. Há inúmeras vantagens na utilização dos sistemas distribuídos em relação aos sistemas concentrados, como por exemplo: melhor distribuição térmica, menor geração de ruídos, dentre outras. Os objetivos de um sistema elétrico de potência para CubeSat são: Manter, tanto nos períodos de sol quanto de eclipse, os subsistemas com alimentação necessária ao seu correto funcionamento; Manter as baterias carregadas para os períodos de eclipse; suprir todos os picos de demanda de energia do CubeSat. Para alcançar esses objetivos e respeitar as restrições físicas impostas pelo padrão CubeSat, os sistemas devem operar com um reduzido número de estágios de conversão de energia, principalmente se esses estiverem operando em cascata; deve empregar um estágio com algoritmo para rastrear o ponto de máxima potência do gerador fotovoltaico e regular a tensão do barramento CC de alimentação das cargas do CubeSat. Este trabalho propõe a utilização de um sistema de energia para CubeSat que utiliza dois conversores com topologia empilhada. Um conversor boost que realiza a regulação do barramento CC distribuído para as cargas do CubeSat, e um conversor buck-boost que possui duas funções: rastrear o ponto de máxima potência (MPPT) do arranjo fotovoltaico e controlar a corrente de carga das baterias. A combinação do controle de carga das baterias e a busca do ponto de máxima potência no mesmo conversor, resulta na redução do tempo de carga das baterias. A conexão dos conversores formando a topologia empilhada proporciona a redução da razão cíclica no conversor boost, e consequentemente, a redução das perdas em condução devido a redução da corrente. Além disso, a composição em série da bateria com a tensão do conversor boost proporciona um aumento da tensão do barramento CC distribuído para as cargas do CubeSat, o que reduz as correntes de carga e novamente as perdas em condução de ambos os conversores. Os resultados experimentais comprovam o funcionamento da topologia proposta e a eficiência do EPS compatível com a eficiência dos sistemas comerciais com arquitetura concentrada.
 Paravras-chave: CubeSat, Sistema Elétrico de Potência, Conversores CC-CC

LINK ORIGINAL
http://mtc-m21b.sid.inpe.br/col/sid.inpe.br/mtc-m21b/2016/07.13.19.33/doc/Dissertacao_Everson_Mattos.pdf

Advances in PV Inverters- Anthon, Alexander-Thesis Doctor of Philosophy in Electrical Engineering at the Technical University of Denmark

Advances in PV Inverters- Anthon, Alexander This report is part of the requirements to achieve the Doctor of Philosophy in Electrical Engineering at the Technical University of Denmark.

 Abstract 
Renewable energies have experienced a significant growth and importance in the last two decades, of which energy from photovoltaic plants are a major contributor. Since solar cells have low efficiencies themselves, however, the necessity of high efficiency power converters at low cost and preferably low complexity leads to new research demands. This is especially true in the field of low cost residential PV inverters where efficiencies are used as major selling arguments. Traditional converter topologies equipped with conventional Silicon based semiconductors to date reach their limitations and new approaches are necessary. Therefore, research areas typically focus on both new topologies and utilizing more advanced semiconductor devices. To this end, semiconductor devices made of Silicon Carbide have been gaining increasing interest in the last two decades after the successful commercialization of high voltage power diodes. By now, the performance potential of switching devices made of Silicon Carbide is commonly accepted, though they have not found commonplace usage within commercial converter systems for several reasons, among others reliability, availability/cost and gate driver complexity. Therefore, more complex Silicon based converters can be used instead to achieve lower semiconductor losses. While there is no absolute solution in which direction to go to achieve the aforementioned design goals, this dissertation will thoroughly investigate two potential approaches and discuss their trade-offs. The contributions are: • Comprehensive loss analysis and identification of major loss contributors within T-Type converter topology operating in inverter and rectifier context. • Evaluation of the use and loss benefits of Silicon Carbide switching devices in the T-Type structure. • Thorough investigation of the Hybrid-Neutral-Point-Clamped (Hybrid-NPC) topology as an alternative for the Silicon Carbide based T-Type converter. • Alternative methodology of semiconductor loss model validation by experimental means. As to the advanced three-level T-Type converter topology, its unusual operation mode is thoroughly described identifying its limitations for high efficiency operation. With these results, the first approach utilizes low loss switching devices and their influence on the semiconductor loss behavior is analyzed. The results show that, for near unity power factor operation, a replacement of only two switching devices per phase leg can greatly reduce the semiconductor losses. The Hybrid-NPC converter can be seen as an attractive and cost competitive alternative to the Silicon Carbide based converter, also allowing to overcome the major drawbacks with the conventional Silicon IGBT based T-Type structure. Both alternatives are based on a semiconductor/topological level and thus this is where the loss reduction occurs. The difficulty in experimentally evaluating only the semiconductor losses within a converter operating context is addressed in this work by presenting an alternative measurement approach. Using known heat loads, and a careful calibration procedure on the device heat sink, analytically obtained semiconductor loss models based on datasheet information and in-circuit switching transitions measurements can be experimentally verified and thus a fair performance comparison between two approaches is enabled.

LINK ORIGINAL
http://orbit.dtu.dk/files/119990172/Advances_in_PV_Inverters.pdf

WEBINAR Inversores Solares e suas Topologias-Data do webinar - 04 Junho 2019, às 19h00

EVENTO GRATUITO 
ENTENDA TUDO SOBRE INVERSORES SOLARES E CONHEÇA AS MELHORES TECNOLOGIAS DISPONÍVEIS NO MERCADO 

Data do webinar - 04 Junho 2019, às 19h00

 INSCREVA-SE AGORA

VISITA A INFORDATA INGENIERIA DE LA INFORMATICA LIMA PERU -29 MAIO 2019

ENG. JUAN VICENTE HUAPAYA (GERENTE GENERAL INFORDATA) E ENG.ARMANDO CAVERO MIRANDA COM AS CANECAS DA COPA AMERICA BRASIL 2019

EQUIPE TECNICO DA INFORDATA JUNTO COM ENG. JUAN VICENTE HUAPAYA

FOI MUITO GRATO VISITAR A UNA DAS MAIORES EMPRESAS DE ENGENHARIA DE INFORMATICA DE LIMA PERU,INFORDATA,TENHO A ALEGRIA DE TER ESTUDADO ENGENHARIA ELETRÔNICA NA UNIVERSIDAD NACIONAL MAYOR DE SAN MARCOS COM O GERENTE GENERAL ENG. JUAN VICENTE HUAPAYA,TEMOS UMA AMIZADE QUE TRANSCENDE O TEMPO,A INFORDATA NASCE EM 1988 ATUALMENTE TEM COMO PRODUTO PRINCIPAL SERVIDORES PARA O SETOR EMPRESARIAL,SETOR CORPORATIVO,USUARIO HOME OFFICE,DESENVOLVIMENTO DE SOFTWARE PARA TELEFONES CELULARES,VENDA DE DRONES,LAPTOPS,UPS,Lousa Digital/Tela Interativa | Alto padrão de qualidade .
 A INFORDATA ACREDITA NA PESQUISA E DESENVOLVIMENTO DE NOVOS SOFTWARES QUE SEJAM APLICADOS EM TELEFONES CELULARES.

Confira os 10 principais benefícios da Lousa Interativa:

1. Torna o aprendizado mais agradável, seguro e participativo.

 2. Facilita a prática pedagógica dos professores, que podem projetar e manipular conteúdos de diversas formas.

 3. É um recurso multimídia versátil que se adapta às necessidades das turmas, de acordo com o seu perfil e nível de aprendizagem.

 4. Amplia a motivação e o interesse dos alunos.

 5. Aumenta a familiarização dos professores com o uso de novas tecnologias.

 6. Possibilita o ensino em tempo real, pois é um recurso que pode ser usado a qualquer momento.

 7. Permite que o professor faça anotações escritas ou que opere softwares, apresente e edite imagens, mostre vídeos, navegue na Internet, entre outas atividades.

 8. Facilita a aprendizagem colaborativa ao estimular o aprendizado e o trabalho em grupo. Isto é, aumenta o diálogo e a cooperação entre professores e alunos.

 9. Possibilita a interação com diversos tipos de conteúdo e autonomia para criação de projetos.

 10. Potencializa a aprendizagem, trazendo recursos diferenciados para aproximar os alunos dos conhecimentos a serem adquiridos em sala de aula.

MAIORES INFORMAÇÕES :https://www.infordata.com.pe/

Start-up Circuit and Power Sequence Design for Initial Start-up of Hysteretic Controlled Step-down Converter- Chai-won Kim-Department of Electronics & Electrical Engineering Graduate School Dankook University-2018

Initial Start-up of Hysteretic Controlled Step-down Converter Chai-won Kim Department of Electronics & Electrical Engineering Graduate School Dankook University

ABSTRACT

 With the rapid spread of battery-based portable products that emphasize convenience like Smart-phones today, the importance and demand for power management circuits are rapidly increasing. Therefore, miniaturization, long operation time, and stability are important for electronic devices, so the power management circuit needs to research and develop low power, miniaturization and light weight in accordance with market demand. Since the power management circuit plays a role of the other system, stable operation is important. In this paper, we design a dual soft-start circuit and a power-up sequence for stable start-up because the entire system starts to run faster as the power management circuit becomes faster. Digital Soft-start has low power consumption and can easily change the reference voltage. In addition, in the case of the digital soft-start circuit, there is an advantage that an external capacitor element is not necessary and the area can be reduced. In the case of the analog type soft-start circuit, the soft-start time can be adjusted by adjusting the external capacitor value according to the user, and the output voltage is linear. Therefore, in this paper, dual soft-start circuit is designed to support both the advantages of digital and analog soft-start. In the case of the power-up sequence design, after the supply voltage of the buck converter is supplied, the required voltage between the internal circuits of the Bias Block is monitored for a stable bias voltage. If the voltage required by one circuit is secured, the next bias circuit starts to operate Respectively. As a result, the power-up sequence is designed in order of Bandgap Reference-> Enable-> LDO-> UVLO-> Mode-> Soft-start so that stable operation can be performed during start-up of the buck converter. As a further study, we proposed a soft-start circuit design method to reduce the start-up time of Buck converter. This design was designed using Samsung BCD 0.13um process, and Psim provided by Korea Power Systems Co. and Cadence provided by Cadence Co. were used. We used the Virtuoso layout editor for layout design and Mentor's caliber for DRC and LVS verification.

LINK
https://www.mediafire.com/file/xuwxxukj7fbcgv5/Hysteretic_Controlled_Step-down_Converter.pdf/file

Design of a highly efficient charger for Nickel-Iron batteries Anil Kumar Ananda Master of Science Thesis Electrical Power Engineering at Delft University of Technology

Design of a highly efficient charger for Nickel-Iron batteries Anil Kumar Ananda Master of Science Thesis Electrical Power Engineering at Delft University of Technology Faculty of Electrical Engineering, Mathematics and Computer Science (EEMCS) · Delft University of Technology
 Abstract 
 Obtaining good performance from stand-alone PV systems requires successful integration of batteries that are reliable, effective, long lasting, environmental-friendly and affordable as it is crucial to deal with variable solar illumination throughout the year. Nickel Iron battery technology (Ni-Fe) is a perfect fit for the solar-powered households as it is satisfies all the requirements. Charge controllers need to be efficiently designed for Ni-Fe batteries for protection from overcharge/discharge. This thesis concentrates on selecting the best topology from B2R converters from the patent 550 of ESA to be applied for designing the charge controller for Ni-Fe batteries. An analysis is carried out to determine the advantage of B2R converters in the patent over conventional buck-boost topologies like SEPIC or Cuk and evaluate their utility for charge control applications. The focal point of topological selection will be the evaluation of topologies on the basis of efficiency and complexity for realistic adaptation into a charge controller. After defining the load power parameters, the operation of the topologies in two different modes of conduction (BCM & CCM) is investigated and an analytical model is developed for losses. Significant factors that play a role in determining the efficiency for varying source parameters (input voltage) are scrutinized. The relative merits of using BCM/CCM for design are inspected by carrying out simulations for loss calculations using the analytical model with data-sheet parameters from realistic components for their suitability for the application. Component selection is done by keeping in mind the prevalent technologies in the market that are costeffective and the procedure followed in the design of magnetics for the topologies in different modes of conduction and its impact on efficiency is discussed and an assessment is carried out on the performance of the components with variations in input voltage for the same power level. The proposed analytical models for switching losses in MOSFETs and overall losses topologies are validated by carrying out experiments on the prototypes of two best topologies in both conduction modes. The results critique the accuracy of the analytical model in determining the actual efficiency of the topologies, the margin of deviation by means of comparison with the experimental results and concludes with suggestions for selecting the most efficient topology and recommends a mode of conduction for best results.
LINK
https://repository.tudelft.nl/islandora/object/uuid:6d77615d-925e-4a7e-88d7-818552522bda/datastream/OBJ/download

Quantum Teleportation From Space Achieved by China!

ONDA VERDE ENERGIA-VOCÊ JÁ PENSOU EM GERAR A SUA PRÓPRIA ENERGIA #EntreNessaOnda

ENERGIA SOLAR
Você Sabia que pode reduzir até 95% da sua conta de energia gerando até 100% da sua energia?
Com a Energia Solar Fotovoltaica isso é possível! Oferecemos soluções completas para micro e mini-geração fotovoltaica, desde o projeto, instalação e regularização junto a distribuidora de energia. Contamos com uma equipe de Engenheiros e Técnicos especializados para realização de todas as etapas do processo.
LINK COM MAIORES INFORMAÇÕES :https://ondaverde.eco.br/

ONDA VERDE-Rua Carlos Gomes, 131 - Centro São Bernardo do Campo - SP-Tel: (11) 4348-7458-BRASIL

POWER ELECTRONICS SOLUTIONS FOR UNINTERRUPTED POWER SUPPLY AND GRID-TIE INVERTERS A Thesis Submitted to the Faculty of Purdue University by Omar N. Nezamuddin

POWER ELECTRONICS SOLUTIONS FOR UNINTERRUPTED POWER SUPPLY AND GRID-TIE INVERTERS A Thesis Submitted to the Faculty of Purdue University by Omar N. Nezamuddin Master of Science in Electrical and Computer Engineering

 ABSTRACT
 Nezamuddin, Omar N. MSECE, Purdue University, December 2014. Power Elec-tronics Solutions for Uninterrupted Power Supply and Grid-Tie Inverters.
 Major Professor: Euzeli dos Santos Jr.
 This thesis proposes two new topologies for Uninterrupted Power Supply (UPS), and a grid-tie microinverter. The rst topic will discuss an on-line transformerless UPS system based on the integrated power electronics converters that is able to con- trol the input power factor, charge the battery, and guarantee backup operation of the system. The main advantages of the proposed UPS are active power factor correc- tion (PFC) without the need of a complex control scheme, and integrated functions of the battery charger circuit and PFC with only three power switches. Operation modes of the system and the PWM strategy is presented in detail. The second topic discussed is of a proposed circuitry for a single-phase back-to-back converter for UPS applications. The main advantages of this topology is higher number of levels at the recti er side, less number of power switches, and no need for a boost inductor at the input side of the converter. The last topic discussed is of a proposed patent pending microinverter. This topic was a project funded by the National Science Foundation, and its aim was to help commercialize the research. This project proposes a solution for a solar inverter called Delta Microinverter that allows easier and faster installation as well as power conversion with higher efficiency. Delta Microinverters innovation is found in its patent-pending shape and in its patent-pending circuitry, i.e., electronics mounted inside of the Delta Microinverter. The Delta Microinverters shape has a housing con gured for rapid mounting using a single fastener and its power electron- ics con guration offers an optimized relationship between the number of levels and number of power switches.
LINK
https://core.ac.uk/reader/81633520

IMPLEMENTATION OF ONLINE IMPEDANCE MEASUREMENT SETUP FOR THREE-PHASE GRID-CONNECTED INVERTERS - TOMMI REINIKKA-Tampere University of Technology Master of Science Thesis

TOMMI REINIKKA: Implementation of online impedance measurement setup for three-phase grid-connected inverters Tampere University of Technology Master of Science Thesis,March 2017

 ABSTRACT
 In the thesis a fast method for measuring the output impedance of a grid-connected inverter by broadband excitation and cross-correlation techniques is studied. The study is made for determining stability of a grid-connected power electronics system by using impedance based stability criterion. The goal of this work is to build a test bench for inverter experiments and to verify the accuracy of the used measurement technique. Renewable power generation, such as solar and wind power, require a way to synchronize and connect to the grid. This is usually done by using grid-parallel inverters. However impedance mismatch between the grid and the interfacing inverter may cause the inverter to generate harmonic resonances. The resonance problems can be analyzed and prevented using analytical inverter models or measured frequency responses. In this thesis pseudo-random sequences and grid emulator are used to measure the inverter output impedance at a high frequency band. The experiments were done by injecting the pseudo-random binary sequence signal into the grid voltage reference. The grid voltages and currents were measured and used to calculate the inverter's frequency response with voltage as the input and current as the output. The measurements were veri ed by comparing them to theoretical values.

LINK
https://core.ac.uk/reader/80539115