This dissertation proposes a high-power, high-frequency and high-density three-level parallel resonant converter for capacitor charging. DC-DC pulsed power converters are widely used in military and medical systems, where the power density requirement is often stringent. The primary means for reducing the power converter size has been to reduce loss for reduced cooling systems and to increase the frequency for reduced passive components. Three-level resonant converters, which combine the merits of the three-level structure and resonant converters, are an attractive topology for these applications. The three-level configuration allows for the use of lower-voltage-rating and faster devices, while the resonant converter reduces switching loss and enhances switching capability. This dissertation begins with an analysis of the influence of variations in the structure of the resonant tank on the transformer volume, with the aim of achieving a high power density three-level DC-DC converter. As one of the most bulky and expensive components in the power converter, the different positions of the transformer within the resonant tank cause significant differences in the transformer's volume and the voltage and current stress on the resonant elements. While it does not change the resonant converter design or performance, the improper selection of the resonant tank structure in regard to the transformer will offset the benefits gained by increasing the switching frequency, sometimes even making the power density even worse than the power density when using a low switching frequency. A methodology based on different structural variations is proposed for a high-density design, as well as an optimized charging profile for transformer volume reduction. The optimal charging profile cannot be perfectly achieved by a traditional output-voltage based variable switching frequency control, which either needs excess margin to guarantee ZVS, or delivers maximum power with the danger of losing ZVS. Moreover, it cannot work for widely varied input voltages. The PLL is introduced to overcome these issues. With PLL charging control, the power can be improved by 10% with a narrow frequency range. The three-level structure in particular suffers unbalanced voltage stress in some abnormal conditions, and a fault could easily destroy the system due to minimized margin. Based on thoroughly analysis on the three-level behaviors for unbalanced voltage stress phenomena and fault conditions, a novel protection scheme based on monitoring the flying capacitor voltage is proposed for the three-level structure, as well as solutions to some abnormal conditions for unbalanced voltage stresses. A protection circuit is designed to achieve the protection scheme. A final prototype, built with a custom-packed MOSFET module, a SiC Schottky diode, a nanocrystalline core transformer with an integrated resonant inductor, and a custom-designed oil-cooled mica capacitor, achieves a breakthrough power density of 140W/in3 far beyond the highest-end power density reported (<100 W/in3) in power converter applications. / Ph. D.

Electric vehicles (EVs) and plug-in hybrid electric vehicles (PHEVs) are gaining popularity because they are more environmentally friendly, less noisy and more efficient. These vehicles have batteries can be charged by on-board battery chargers that can be conductive or inductive. In conductive chargers, the charger is physically connected to the grid by a connector. With the inductive chargers, energy can be transferred wirelessly over a large air-gap through inductive coupling, eliminating the physical connection between the charger and the grid. A typical on-board battery charger consists of a boost power factor correction (PFC) converter followed by a dc-dc converter. This dissertation focuses on the design, modeling and control of a bidirectional dc-dc converter for conductive battery charging application. In this dissertation, a detailed design procedure is presented for a bidirectional CLLLC-type resonant converter for a battery charging application. This converter is similar to an LLC-type resonant converter with an extra inductor and capacitor in the secondary side. Soft-switching can be ensured in all switches without additional snubber or clamp circuitry. Because of soft-switching in all switches, very high-frequency operation is possible, thus the size of the magnetics and the filter capacitors can be made small. To further reduce the size and cost of the converter, a CLLC-type resonant network with fewer magnetics is derived from the original CLLLC-type resonant network. First, an equivalent model for the bidirectional converter is derived for the steady-state analysis. Then, the design methodology is presented for the CLLLC-type resonant converter. Design of this converter includes determining the transformer turns ratio, design of the magnetizing inductance based on ZVS condition, design of the resonant inductances and capacitances. Then, the CLLC-type resonant network is derived from the CLLLC-type resonant network. To validate the proposed design procedure, a 3.5 kW converter was designed following the guidelines in the proposed methodology. A prototype was built and tested in the lab. Experimental results verified the design procedure presented. The dynamics analysis of any converter is necessary to design the control loop. The bandwidth, phase margin and gain margin of the control loops should be properly designed to guarantee a robust system. The dynamic analysis of the resonant converters have not been extensively studied, with the previous work mainly concentrated on the steady-state models. In this dissertation, the continuous-time large-signal model, the steady-state operating point, and the small-signal model are derived in an analytical closed-form. This model includes both the frequency and the phase-shift control. Simulation and experimental verification of the derived models are presented to validate the presented analysis. A detailed controller design methodology is proposed in this dissertation for the bidirectional CLLLC-type resonant converter for battery charging application. The dynamic characteristics of this converter change significantly as the battery charges or discharges. And, at some operating points, there is a high-Q resonant peaking in the open-loop bode-plot for any transfer functions in this converter. So, if the controller is not properly designed, the closed-loop system might become unstable at some operating points. In this paper, a controller design methodology is proposed that will guarantee a stable operation during the entire operating frequency range in both battery charging mode (BCM) and regeneration mode (RM). To validate the proposed controller design methodology, the output current and voltage loop controllers are designed for a 3.5 kW converter. The step response showed a stable system with good transient performance thus validating the proposed controller design methodology. / Ph. D.

Making electricity grids smarter and facilitating them with integration of renewable energy sources (RES) and energy storage are fairly accepted as the necessary steps to achieve a sustainable and secure power industry. To enable Net-zero energy and optimize power management for future homes or buildings, DC electric distribution systems (DC Nano-grid) find feasibility and simplicity for integrating renewable energy sources and energy storage. However, integrating the sources and loads in a simple, robust and smart way is still challenging. High voltage lithium-ion battery should be seriously considered concerning the overcharge/over-discharge risk. Dissipative cell equalization and its performance are studied. Non-dissipative equalization methods are reviewed using an energy flow chart. Typical charging schemes and the related over-charge risk are illustrated. A Lithium-ion battery charging profile based on VCell_Max/Min monitoring is proposed and validated with experimental results in an 8.4kW bidirectional battery charger for DC future home. For the DC future home emulator testbed, a grid interface converter, i.e. energy control center (ECC) converter, is reviewed with functions identification. A PV system with different configurations is compared to further expand the common MPPT region, and a DC-DC converter is designed as the interface between PV panels and DC bus, facilitating maximum power point tracking (MPPT) as well as fulfill the system energy management requirement. An 8.4kW multi-phase bidirectional battery charger with Si IGBT in DCM operation is designed to achieve high efficiency and to be the interface converter between lithium-ion battery and DC bus, enhancing the battery system management as well as increasing the system reliability. To integrate all the sources and loads in a simple, reliable and smart way, this thesis proposes a distributed droop control method and smart energy management strategy to enhance the Net-zero electric energy cost. All of the control strategies are applied to the DC future home with interactions among the energy control center (ECC), renewable energy sources, energy storage and load within a day/24 hours. System level energy management control strategies for Net-zero electric energy cost are examined and illustrated. A 10kW future home emulator testbed is built and introduced for concepts validation. / Master of Science

Due to the concerns regarding increasing fuel cost and air pollution, plug-in electric vehicles (PEVs) are drawing more and more attention. PEVs have a rechargeable battery that can be restored to full charge by plugging to an external electrical source. However, the commercialization of the PEV is impeded by the demands of a lightweight, compact, yet efficient on-board charger system. Since the state-of-the-art Level 2 on-board charger products are largely silicon (Si)-based, they operate at less than 100 kHz switching frequency, resulting in a low power density at 3-12 W/in3, as well as an efficiency no more than 92 - 94% Advanced power semiconductor devices have consistently proven to be a major force in pushing the progressive development of power conversion technology. The emerging wide bandgap (WBG) material based power semiconductor devices are considered as game changing devices which can exceed the limit of Si and be used to pursue groundbreaking high frequency, high efficiency, and high power density power conversion. Using wide bandgap devices, a novel two-stage on-board charger system architecture is proposed at first. The first stage, employing an interleaved bridgeless totem-pole AC/DC in critical conduction mode (CRM) to realize zero voltage switching (ZVS), is operated at over 300 kHz. A bi-directional CLLC resonant converter operating at 500 kHz is chosen for the second stage. Instead of using the conventional fixed 400 V DC-link voltage, a variable DC-link voltage concept is proposed to improve the efficiency within the entire battery voltage range. 1.2 kV SiC devices are adopted for the AC/DC stage and the primary side of DC/DC stage while 650 V GaN devices are used for the secondary side of the DC/DC stage. In addition, a two-stage combined control strategy is adopted to eliminate the double line frequency ripple generated by the AC/DC stage. The much higher operating frequency of wide bandgap devices also provides us the opportunity to use PCB winding based magnetics due to the reduced voltage-second. Compared with conventional litz-wire based transformer. The manufacture process is greatly simplified and the parasitic is much easier to control. In addition, the resonant inductors are integrated into the PCB transformer so that the total number of magnetic components is reduced. A transformer loss model based on finite element analysis is built and used to optimize the transformer loss and volume to get the best performance under high frequency operation. Due to the larger inter-winding capacitor of PCB winding transformer, common mode noise becomes a severe issue. A symmetrical resonant converter structure as well as a symmetrical transformer structure is proposed. By utilizing the two transformer cells, the common mode current is cancelled within the transformers and the total system common mode noise can be suppressed. In order to charge the battery faster, the single-phase on-board charger concept is extended to a higher power level. By using the three-phase interleaved CLLC resonant converter, the charging power is pushed to 12.5 kW. In addition, the integrated PCB winding transformer in single phase is also extended to the three phase. Due to the interleaving between each phase, further integration is achieved and the transformer size is further reduced. / PHD / Plug-in electric vehicles (PEVs) are drawing more and more attention due to the advantages of energy saving, low CO₂ emission and cost effective in the long run. The power source of PEVs is a high voltage DC rechargeable battery that can be restored to full charge by plugging to an external electrical source, during which the battery charger plays an essential role by converting the grid AC voltage to the required battery DC voltage. Silicon based power semiconductor devices have been dominating the market over the past several decades and achieved numerous outstanding performances. As they almost reach their theatrical limit, the progress to purse the high-efficiency, high-density and high-reliability power conversion also slows down. On this avenue, the emerging wide bandgap (WBG) material based power semiconductor devices are envisioned as the game changer: they can help increase the switching frequency by a factor of ten compared with their silicon counterparts while keeping the same efficiency, resulting in a small size, lightweight yet high efficiency power converter. With WBG devices, magnetics benefit the most from the high switching frequency. Higher switching speed means less energy to store during one switching cycle. Consequently, the size of the magnetic component can be greatly reduced. In addition, the reduced number of turns provides the opportunity to adopt print circuit board as windings. Compared with the conventional litz-wire based magnetics, planar magnetics not only can effectively reduce the converter size, but also offer improved reliability through automated manufacturing process with repeatable parasitics. This dissertation is dedicated to address the key high-frequency oriented challenges of adopting WBG devices (including both SiC and GaN) and integrated PCB winding magnetics in the battery charger applications. First, a novel two-stage on-board charger system architecture is proposed. The first stage employs an interleaved bridgeless totem-pole AC/DC with zero voltage switching, and a bi-directional CLLC resonant converter is chosen for the second stage. Second, a PCB winding based transformer with integrated resonant inductors is designed, so that the total number of magnetic components is reduced and the manufacturability is greatly improved. A transformer loss model based on finite element analysis is built and employed to optimize the transformer loss and volume to get the best performance under high frequency operations. In addition, a symmetrical resonant converter structure as well as a symmetrical transformer structure is proposed to solve the common noise issue brought by the large parasitic capacitance in PCB winding magnetics. By utilizing the two transformer cells, the common mode current is cancelled within the transformers, and the total system common mode noise can be suppressed. Finally, the single-phase on-board charger concept is extended to a higher power level to charge the battery faster. By utilizing the three-phase interleaved CLLC resonant converter as DC/DC stage, the charging power is pushed to 12.5 kW. In addition, the integrated PCB winding magnetic in single phase is also extended to the three phase. Due to the interleaving between the three phase, further integration is achieved and the transformer size is further reduced.

The current concerns about global warming are increasing the demands for electric vehicles (Ou- chi, Bando, Kodani, Hirata &amp; Mubin, 2012).With the increasing demands, electric boats have now come into focus (Sierzchula, 2014). However, there is yet to be developed standards for charging of electric boats.This is where this thesis project comes in, as this thesis is a part of the E-Sea Power project,which is a project to develop a new and safe standard for charging of electric boats.The thesis project was completed at the company No Picnic in Stockholm, through the work of my final master degree course, in the education of Industrial Design Engineering, taught at Luleå Uni- versity of Technology. The objective of the thesis project was to provide a basis for the facilitation of the standardization of chargers for boats, with the possibility of full-scale tests. Where the final aim of the project was to develop both a normal charger standard and a quick charger that is to be mounted in a harbor, being able to utilize the harbor’s own electricity grid.Where in this context, a normal charger is a slower charger that charges with the users own cord and where a quick charger is a fast charger which has a built-in charger cord and handle. The project was divided into need, design, and function to make it structured and easy to follow, going through the design phases Immersion, Ideation, and Implementation.Throughout the project the current state was firsts analyzed, going on to several brainstorming and evaluation techniques and then ending with the building of final CAD prototypes, of both a normal charger and a quick charger, through the use of the software Solidworks, Keyshot, Photoshop and Maxwell.The projects focus has been on finding creative and ergonomic new solutions, with good user experience and accessibility. The final result of the project is two modular new chargers, with belonging to the same product family. Both a quick charger, which has had the thesis main focus and a normal charger, which has also been developed. The quick charger is a tall charging post that has a built-in lamp consisting of four fluorescent lamps and a, on the outside hanging, charging cord mounted at the top.The charger has two component houses which house necessary components. One that houses the CCS charger female and infor- mation label and one that houses the screen, IR sensor and emergency stop. The main feature of the final quick charger is its charging arm, which bends down with a hidden hinge, enabling the required total reach of 5 meters, while helping lift the charging cord for the user and giving the best possible light were the user is. The normal charger is also a charging post with the same type of house as the quick charger. How- ever the charger post is much shorter and it has only one house, which houses two Type 2 females instead of one CCS female.The normal charger also has a different lamp consisting of small LEDs, so that the user is not disturbed by its brightness at its lower hight, but still gaining enough light during use, where the surrounding light is lacking. / Den nuvarande oron för global uppvärmning ökar kraven på el-fordon (Ouchi, Bando, Kodani, Hirata &amp; Mubin, 2012). Med de ökande kraven har nu de elektriska båtarna kommit i fokus (Sier- zchula, 2014). Det har emellertid ännu inte utvecklats standarder för laddning av elektriska båtar. Det är här det här master projektet kommer in, då detta projekt ingår i E-Sea Power-projektet, som är ett projekt för att utveckla en ny och säker standard för laddning av elektriska båtar. Projektet slutfördes på företaget No Picnic i Stockholm, genom mitt examensarbete, vid utbildningen civil- ingenjörsutbildningen i teknisk design, undervisad vid Luleå tekniska universitet. Målet med projektet var att skapa en grund för att underlätta standardiseringen av laddare för båtar, med möjlighet till fullskaliga tester. Där det slutliga målet med projektet var att utveckla både en normalladdare standard och en snabbladdare som ska monteras i en hamn och kunna utnyttja ham- nens egna elnät. I det här sammanhanget är en normalladdare en långsammare laddare som laddar med användarens egen kabel och en snabbladdare är en snabb laddare som har en egen inbyggd kabel med ett handtag. Projektet var uppdelat i behov, design och funktion för att göra det strukturerat och lätt att följa. Det gick även igenom designfaserna Immersion, Ideation och Implementation. Hela projektet bör- jade med analyseradet av det nuvarande tillståndet och fortsatte sedan med diverse brainstorming och utvärderingstekniker och slutade sedan med byggandet av slutliga CAD-prototyper, både av en normalladdare och en snabbladdare, med hjälp av programmen Solidworks, Keyshot, Photoshop och Maxwell. Projektets fokus har varit att hitta kreativa och ergonomiska nya lösningar med bra användarupplevelse och tillgänglighet. Det slutliga resultatet av projektet är två modulära nya laddare, som tillhör samma produktfamilj. Både en snabbladdare, som har haft huvudfokus och en normalladdare, som också har utvecklats. Snabbladdaren är en hög laddningsstolpe som har en inbyggd lampa som består av fyra lysrörslam- por och en utvändigt hängande laddningssladd monterad på toppen. Laddaren har två komponent- hus ett som rymmer CCS laddarens hona och informationsetikett och ett som rymmer skärmen, IR sensorn och nödstoppet. Huvudfunktionen hos den slutliga snabbladdaren är dess laddarm som böjer sig ned med ett dolt gångjärn, vilket möjliggör den totala räckvidden på 5 meter, samtidigt som den hjälper till att lyfta laddkabeln åt användaren och ger bästa möjliga ljus där användaren är. Den vanliga laddaren är också en laddstolpe med samma typ av hus som snabbladdaren. Laddstolpen är dock mycket kortare och den har bara ett hus, som rymmer två Type 2-honor i stället för en CCS-hona. Normalladdaren har också en annan lampa än snabbladdaren som består av små lysdio- der, så att användaren inte störs av ljusstyrkan vid dess lägre placering, men fortfarande får tillräckligt med ljus vid användning, där det omgivande ljuset är bristande.

本文係就有關審計契約問題之期刊及文獻從事學理上之介紹與探討。由於現行專業人 員的職業道德觀念中，強調財務利益對專業人員操寸與獨立性可能產生不利的負面效 果。因此如何在契約關係與計價問題間取得適當的調適，即是本文之研究動機。 本文之內容乃強調審計功能在恣理理論中的價值，並就各種經濟因素影響下，介紹契 約關係的建立與計價模式的產生。以期藉審計契約的成立，在個體方面使契約的現有 與潛在之相關人士獲得最大利益；在總體方面使整個經濟社會有限的資源作最佳之分 配。

Orientador: Prof. Dr. Thales Sousa / The world has been searching different sorts of technology to mitigate any energetic crises in function in a growing demand of energy, resulting by generation of pollutants from the actual energy source uses. Developments of new technology application as electric transport with rechargeable cell are actually trends to mitigate these problems, cooperating to reduce energetic and environmental issues. In order, the present work proposes a two electric vehicles study, emphasizing the different classification of each other, depending on how electric and combustion energies are integrated. Different promising technological trend are presented to enhance the driving autonomy from the vehicles as the different ways to storage of energy and fuel feeding methods. Otherwise, the impacts on distribution network, environmental impacts and economic impacts are defined. Ultimately, it¿s made analysis bidirectional battery charger to an electric vehicle, considering every charger module in coupled manner, as the practice must be provided. The charger is made-up by a CA/CC Full-bridge bidirectional converter with power factor controller PFC, and CA/CC Full-bridge bidirectional converter isolation properties. These converters work altogether, providing from the energy distribution network to charge a battery cell and providing energy from the battery cell to the energy distribution network. / Dissertação (mestrado) - Universidade Federal do ABC, Programa de Pós-Graduação em Engenharia Elétrica, 2014. / O mundo vem buscando diferentes tecnologias que mitiguem a possibilidade de uma crise energética, em função de uma demanda crescente de energia e uma crise ambiental, resultante das emissões de poluentes advinda das fontes de energia atualmente utilizadas. O desenvolvimento de novas tecnologias, como por exemplo, os meios de transporte elétricos recarregáveis, contribuem para que esses problemas sejam mitigados, colaborando para a minimização dos problemas energéticos e ambientais. Nesse sentido, o presente trabalho propõe o estudo dos veículos elétricos, enfatizando as diferentes classificações dos mesmos, dependendo de como a energia elétrica e a energia de combustão são integradas. São apresentadas também, as tecnologias de geração de energia mais promissoras para o aumento de autonomia de condução, bem como as formas de armazenamento da energia e como os veículos elétricos são alimentados. Adicionalmente, são indicados os impactos dos veículos elétricos na rede de distribuição, os impactos ao ambiente e os impactos econômicos. Por último, é feita uma análise de um carregador de baterias bidirecional para um veículo elétrico, considerando todos os módulos do carregador de maneira acoplada, conforme deve ser previsto na pratica. O carregador esta composto por um conversor bidirecional CA/CC Full-Bridge com propriedades de correção de fator de potência e, um conversor bidirecional CC/CC Full-Bridge isolado. Estes conversores trabalham em conjunto fornecendo da rede de distribuição energia para carregar um banco de baterias e entregando energia das baterias à rede de distribuição.

Submitted by Izabel Franco (izabel-franco@ufscar.br) on 2016-09-30T17:56:23Z No. of bitstreams: 1 DissFMO.pdf: 2016401 bytes, checksum: 6866947ec8d256db2aefd27468b572ce (MD5) / Approved for entry into archive by Marina Freitas (marinapf@ufscar.br) on 2016-10-04T17:30:18Z (GMT) No. of bitstreams: 1 DissFMO.pdf: 2016401 bytes, checksum: 6866947ec8d256db2aefd27468b572ce (MD5) / Approved for entry into archive by Marina Freitas (marinapf@ufscar.br) on 2016-10-04T17:30:30Z (GMT) No. of bitstreams: 1 DissFMO.pdf: 2016401 bytes, checksum: 6866947ec8d256db2aefd27468b572ce (MD5) / Made available in DSpace on 2016-10-04T17:30:37Z (GMT). No. of bitstreams: 1 DissFMO.pdf: 2016401 bytes, checksum: 6866947ec8d256db2aefd27468b572ce (MD5) Previous issue date: 2015-04-30 / Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) / Nowadays the control of industrial pollution is essential. Through filtering, you can remove the suspended solids in gases. It has been need for more efficient methods for gas filtration in order to reduce waste generation and decrease energy consumption. In this study was proposed to investigate the behavior of the particulate matter, cement and the influence of particle size in formation of gas dust cake, with and without eletrostatic charged. The filter in order to determine aspects were analyzed and compare their characteristics after filtration, defining which one operationally more suitable for this process. In this investigation the study aims optimize the filtration operation. In order to obtain a greater retention of particulates. In this sense, fabric filter were analyzed, glass and polypropylene filter, while gas filtration. Cement was used as particulate material with grain sizes 8, 14 and 20μm, the corona chargering was added in the filtration of gas during the formation of dust cake. The tests were conduction in an attempt to understand this effect the electrostatic charge, improve and increase the service life of the filter media. Was necessary to adapt it to the equipment one system gas filtration, localized in Department of Chemical Engineering (DEQ) of Federal University of São Carlos (UFSCar), for receive the corona charged. The experiment was conducted from voltage of 0 to -2 kV test with a filtration rate of 10 cm/s, and the mass flow of 9 mg/s. With the tests done, it possible show that, with the application the corona chargering the dust cake changes. It can be that the particle size directly affects the filtration efficiency and the load, can increase the efficiency the collect to particulate and decrease pressure drop during filtration of gases. / Atualmente o controle da poluição industrial é essencial. Através da filtração, é possível remover os sólidos suspensos nos gases. Tem-se então a necessidade de métodos eficientes para filtração de gases a fim de reduzir a geração de resíduos e diminuir o consumo de energia. O presente estudo objetivou investigar o comportamento do material particulado, cimento e a influência do seu tamanho de partícula na formação da torta de filtração de gases, com e sem carregamento eletrostático. Foram analisados os aspectos do filtro com intuito de determinar e comparar suas características após as filtrações, definindo qual delas será mais adequada operacionalmente para este processo. Além destas investigações o estudo busca otimizar a operação de filtração. Para que se possa obter uma maior retenção de particulados. Neste sentido, foram analisados filtros de tecidos, de fibra de vidro e polipropileno, durante a filtração de gases. Utilizou-se o cimento como material particulado, com granulometrias de 8, 14 e 20μm, o carregamento corona foi adicionado na filtração durante a formação da torta de filtração. Os testes foram realizados na tentativa de compreender esses efeitos causados a partir de cargas eletrostáticas, objetivando melhorar e aumentar o tempo de vida útil dos meios filtrantes. Para isso adaptou-se um sistema de filtração de gases, existente no Departamento de Engenharia Química (DEQ) da Universidade Federal de São Carlos (UFSCar), para receber um carregador corona. Posteriormente determinou-se o ponto ótimo de operação a uma vazão mássica de 9 mg/s e velocidade de filtração de 10 cm/s, variando-se a tensão da unidade entre 0, e -2,0 kV. Através dos ensaios realizados foi possível observar que, com a aplicação da corrente corona, ocorreu uma alteração na formação da torta de filtração. Pode-se dizer que o tamanho da partícula afeta diretamente a eficiência da filtração e que a carga, pode aumentar a eficiência de coleta das partículas e diminuir a perda de carga durante a filtração de gases.

CoordenaÃÃo de AperfeiÃoamento de Pessoal de NÃvel Superior / This work presents a study and design of an electronic power converter topology for on-board application in a battery charger for plug-in electric vehicles. The proposed topology is based on AC-DC converter Buck+Boost, which one is very attractive for this application due to its buck and boost characteristics in a single-stage power processing. Furthermore, this topology presents reduced weight and volume, since there is no transformer and only few components are presented in its structure. A theoretical study is performed through of qualitative and quantitative analysis, besides it is investigated the switching process and losses in the converter components. It is also performed a design example of a battery charger with rated output power of 1 kW, input voltage 220 Vac RMS and output voltage of 162 Vdc, corresponding to 12 batteries connected in series. A prototype for the indicated specifications was constructed in laboratory and tested experimentally. The simulation and experimental results obtained are used to validate the theoretical analysis and design. For rated load, it was obtained an efficiency of 96.5% and a power factor of 0.992, thus showing the effectiveness of the proposed converter. / Este trabalho apresenta o estudo e desenvolvimento de uma topologia de conversor eletrÃnico de potÃncia para a aplicaÃÃo embarcada em um carregador de baterias para veÃculos elÃtricos recarregÃveis atravÃs da rede elÃtrica. A topologia escolhida à baseada no conversor CA-CC Buck+Boost, onde a mesma torna-se bastante atrativa para este tipo de aplicaÃÃo por apresentar as caracterÃsticas elevadora e abaixadora de tensÃo em um Ãnico estÃgio de processamento de energia. AlÃm disso, esta topologia apresenta reduzido volume e peso, devido ao fato de nÃo apresentar transformador e possuir poucos componentes em sua estrutura. Um estudo teÃrico à realizado atravÃs das anÃlises qualitativa e quantitativa, alÃm das anÃlises do processo de comutaÃÃo e das perdas nos componentes do conversor. Neste trabalho à realizado um exemplo de projeto do carregador de baterias para aplicaÃÃo em veÃculos elÃtricos de 1 kW de potÃncia de saÃda, tensÃo de entrada eficaz de 220 Vca e tensÃo de saÃda de 162 Vcc, correspondente a 12 baterias conectadas em sÃrie. Um protÃtipo com as especificaÃÃes indicadas foi construÃdo e testado experimentalmente em laboratÃrio. Os resultados de simulaÃÃo e experimentais obtidos validaram a anÃlise teÃrica e o projeto realizado. Para carga nominal, foi obtido rendimento de 96,5% e fator de potÃncia de 0,992, comprovando assim o funcionamento da topologia utilizada.

CoordenaÃÃo de AperfeiÃoamento de Pessoal de NÃvel Superior / This work presents the study and implementation of an ac-dc &#262;uk converter based on the three state switching cells applied in charger stations for electric vehicles. This converter has, as main characteristics, reduction of conducting power losses in the semiconductors, a single stage topology and current source behavior for both input and output terminals. As drawbacks, the topology presents: the voltage across the semiconductors is equal to the sum of the input and the output voltages, and a difference between the current values through the semiconductors caused by an inappropriate layout of the power prototypes or by a lack of symmetry between the control signals. The analysis of the converter is made through the qualitative and quantitative studies, beyond the analysis of the semiconductor losses which are presented as well. The current and voltage of the battery are controlled by the average current mode technique, which consist in a fast current control loop if compared with the terminals battery voltage control loop. The topology is design for 1 kW output power, 220 V in input voltage and 162 V in the output terminals (12 batteries in series connection). Experimental results for resistive load, as well batteries, are shown in order to verify the functionalities of the topology and its characteristics. / Este trabalho apresenta o estudo e desenvolvimento de um conversor ca-cc &#262;uk baseado na cÃlula de comutaÃÃo trÃs estados para aplicaÃÃo em carregadores de baterias para veÃculos elÃtricos. As principais caracterÃsticas deste conversor sÃo: a reduÃÃo das perdas por conduÃÃo nos interruptores controlados, um Ãnico estÃgio de processamento de potÃncia e caracterÃstica de fonte de corrente na entrada e na saÃda. Como inconvenientes a topologia apresenta: a tensÃo sobre os semicondutores igual à soma das tensÃes de entrada e saÃda e o desequilÃbrio de corrente atravÃs dos componentes quando hà assimetria no layout da placa de potÃncia ou nos sinais de comando dos interruptores. Um estudo teÃrico à realizado atravÃs das anÃlises qualitativa e quantitativa, alÃm das anÃlises do processo de comutaÃÃo e das perdas nos componentes do conversor. Para controlar o fluxo de potÃncia da rede elÃtrica para as baterias à utilizada a estratÃgia de controle modo corrente mÃdia, sendo que, a mesma apresenta uma malha de corrente rÃpida que monitora a corrente de entrada e uma malha de tensÃo lenta que supervisiona a tensÃo sobre os terminais da bateria. Neste trabalho à realizado o projeto do carregador de baterias para aplicaÃÃo em veÃculos elÃtricos com 1 kW de potÃncia, tensÃo de entrada eficaz de 220 V e tensÃo de saÃda de 162 V, correspondente a 12 baterias conectadas em sÃrie. Um protÃtipo com as especificaÃÃes indicadas foi construÃdo e testado experimentalmente em laboratÃrio e os resultados de simulaÃÃo e experimentais obtidos sÃo utilizados para validar a anÃlise teÃrica e o projeto realizado. Foram realizados testes com carga puramente resistiva e em seguida com um banco de baterias, que comprovaram o funcionamento da topologia.