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MS2SV: Tradução de modelos em Simulink para VHDL-AMS

Silva, Alexandre César Rodrigues da; Grout, I. A.
Fonte: Institute of Electrical and Electronics Engineers (IEEE) Publicador: Institute of Electrical and Electronics Engineers (IEEE)
Tipo: Artigo de Revista Científica Formato: 663-672
POR
Relevância na Pesquisa
25.81%
This paper presents a methodology and a tool for projects involving analogue and digital signals. A sub-systems group was developed to translation a Matlab/Simulink model in the correspondent structural model described in VHDL-AMS. The developed translation tool, named of MS(2)SV, can reads a file containing a Simulink model translating it in the correspondent VHDL-AMS structural code. The tool also creates the directories structure and necessary files to simulate the model translated in System Vision environment. Three models of D/A converters available commercially that use R-2R ladder network were studied. This work considers some of challenges set by the electronic industry for the further development of simulation methodologies and tools in the field of mixed-signal technology. Although the objective of the studies has been the D/A converter, the developed methodology has potentiality to be extended to consider control systems and mechatronic systems.

Inversor monofásico sincronizado para a conexão de um gerador eólico à rede elétrica

Maccarini, Mateus Costa
Fonte: Universidade Federal de Santa Catarina Publicador: Universidade Federal de Santa Catarina
Tipo: Dissertação de Mestrado Formato: xxv, 153 f.| il., graf., tabs.
POR
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Dissertação (mestrado) - Universidade Federal de Santa Catarina, Centro Tecnológico, Programa de Pós-Graduação em Engenharia Elétrica, Florianópolis, 2009.; O objetivo principal deste trabalho é o estudo, projeto e implementação de um conversor CC/CA para a conexão de um gerador eólico à rede elétrica. Faz-se isso utilizando-se um inversor monofásico, com modulação PWM a três níveis, ligado à rede através de um transformador de baixa freqüência. São controladas três variáveis distintas no conversor: a corrente de saída, que deve ser senoidal e com baixa distorção harmônica, a tensão do barramento CC de entrada, que se deve manter regulada e com a ondulação projetada, e a componente média de corrente no primário do transformador, para se evitar que esse último sature. Inicialmente faz-se uma breve introdução sobre o uso da energia eólica, logo em seguida, estuda-se o estágio de potência, malhas de controle e compensadores utilizados e, por fim, implementa-se um protótipo para que seja feita a comprovação experimental de toda a teoria desenvolvida.; The aims of this work are the study, design and implementation of a dc/ac converter for the connection of a wind power generator to the electric grid. It makes use of a single-phase inverter...

Conversor CC-CC trifásico ZVS PWM de três níveis

Agostini Junior, Eloi
Fonte: Florianópolis Publicador: Florianópolis
Tipo: Tese de Doutorado Formato: 267 p.| il., grafs., tabs.
POR
Relevância na Pesquisa
25.93%
Tese (doutorado) - Universidade Federal de Santa Catarina, Centro Tecnológico. Programa de Pós-Graduação em Engenharia Elétrica.; Esta tese propõe uma topologia de conversor CC-CC trifásico de três níveis, modulado por largura de pulso e com comutação suave. A análise estática dos sete modos de condução descontínua e dos seis modos de condução contínua é apresentada no decorrer do documento. A análise dinâmica do conversor voltada para a operação em condução contínua também é apresentada, fornecendo a função de transferência que relaciona a tensão de saída com a razão cíclica. A comutação dos doze interruptores comandados é investigada em detalhes, enfatizando-se a condução contínua, onde há a possibilidade de obtenção de comutação suave do tipo ZVS em todos os doze interruptores do conversor. Para a comprovação das análises apresentadas, realiza-se a simulação numérica e a experimentação através de um protótipo de 10 kW, 800 V de tensão de entrada, 200 V de tensão de saída e 40 kHz do conversor proposto.; This thesis proposes a three-level three-phase pulse-width-modulated soft-switched DC-DC converter. The static analysis of seven discontinuous conduction modes and six continuous conduction modes is carried out. The dynamic analysis is also performed...

Conversor CC-CC buck+boost multinível bidirecional

Costa, Levy Ferreira
Fonte: Universidade Federal de Santa Catarina Publicador: Universidade Federal de Santa Catarina
Tipo: Dissertação de Mestrado Formato: 232 p.| il., gras., tabs.
POR
Relevância na Pesquisa
25.93%
Dissertação (mestrado) - Universidade Federal de Santa Catarina, Centro Tecnológico, Programa de Pós-graduação em Engenharia Elétrica, Florianópolis, 2013; Este trabalho apresenta uma nova topologia de conversor cc-cc Buck+Boost bidirecional multinível, adequado para aplicação em alta tensão. Esta topologia é gerada a partir da associação de um conversor Buck e um conversor Boost, ambos bidirecionais e multiníveis. As topologias multinível são obtidas a partir da generalização dos conversores Buck e Boost de três níveis. As principais características do conversor Buck+Boost proposto são: redução dos esforços de tensão nos semicondutores e capacitores,- tornando-o possível para aplicação em alta tensão; capacidade de processamento de fluxo bidirecional de energia; frequência de operação dos magnéticos múltipla da freqüência de comutação dos interruptores. Além disso, o conversor Buck+Boost proposto apresenta oito capacitores, cujas tensões devem ser balanceadas para a correta operação do conversor. Portanto, uma estratégia de balanço das tensões nos capacitores da topologia é apresentada e uma técnica de controle utilizando uma ação de feedforward é proposta. Para validar a análise teórica...

Conversor CC-CC tipo T ZVS PWM

Bandeira Junior, Delvanei Gomes
Fonte: Universidade Federal de Santa Catarina Publicador: Universidade Federal de Santa Catarina
Tipo: Dissertação de Mestrado Formato: 1 v.| il., grafs., tabs.
POR
Relevância na Pesquisa
26.11%
Dissertação (mestrado) - Universidade Federal de Santa Catarina, Centro Tecnológico, Programa de Pós-Graduação em Engenharia Elétrica, Florianópolis, 2014.; Este trabalho apresenta o estudo de um conversor CC-CC isolado com comutação suave, saída em corrente, para aplicações envolvendo altas potências, com nome T-Type Zero Voltage Switching Pulse Width Modulated dc-dc converter(TT-ZVS-PWM). O conversor a ser estudado possui quatro interruptores. Dois deles são submetidos à tensão de entrada, já os outros dois são submetidos à metade da tensão de entrada. Todos os interruptores comutam sob tensão nula. O conversor proposto possui as seguintes semelhanças com os conversores Full Bridge Zero Voltage Switching(FB-ZVS-PWM) e Three Level Zero Voltage Switching(TL-ZVS-PWM): (a) Operação simétrica (b) Modulação por largura de pulso com frequência constante (c) comutação sob tensão nula e (d) tensão de saída do conversor com três níveis, a ser aplicada nos terminais do primário do transformador. O trabalho é dividido em análise teórica, análise do modelo de pequenos sinais do conversor e roteiro para projeto do conversor. Um protótipo com 3 kW, 400 V de entrada, 60V de saída e frequência de comutação de 50 kHz comprova a análise desenvolvida. A eficiência obtida no protótipo foi de 93% para carga nominal e de 95...

Three-level converter in offshore wind energy systems: new strategy for unbalancing in capacitors voltage

Melício, Rui; Mendes, Victor
Fonte: ELSEVIER Publicador: ELSEVIER
Tipo: Aula
ENG
Relevância na Pesquisa
96.15%
This paper is on offshore wind energy conversion systems with full-power three-level converter and permanent magnet synchronous generator. The multi-level converters, namely three-level converters are limited by unbalance voltages in the direct current link capacitors. In order to lessen this limitation, a new control strategy for the selection of the output voltage vectors is proposed. The aim is to evaluate the performance of the three-level converter with the new strategy.

Offshore wind turbine simulation: multibody drive train. Back-to-back NPC (neutral point clamped) converters. fractional-order control

Melício, Rui; Seixas, Mafalda; Mendes, Victor
Fonte: Energy - Elsevier Publicador: Energy - Elsevier
Tipo: Artigo de Revista Científica
ENG
Relevância na Pesquisa
35.94%
This paper is on offshore wind energy conversion systems installed on the deep water and equipped with back-to-back neutral point clamped full-power converter, permanent magnet synchronous generator with an AC link. The model for the drive train is a five-mass model which incorporates the dynamic of the structure and the tower in order to emulate the effect of the moving surface. A three-level converter and a four-level converter are the two options with a fractional-order control strategy considered to equip the conversion system. Simulation studies are carried out to assess the quality of the energy injected into the electric grid. Finally, conclusions are presented.

Three-level Converter in Offshore Wind Energy Systems: New Strategy for Unbalancing in Capacitors Voltage

Seixas, Mafalda; Melicio, Rui; Mendes, Victor; Figueiredo, Joao
Fonte: ELSEVIER - Procedia Technology Publicador: ELSEVIER - Procedia Technology
Tipo: Parte de Livro
ENG
Relevância na Pesquisa
86.01%
This paper is on an offshore wind energy conversion system equipped with full-power three-level converter and permanent magnet synchronous generator. Multi-level converters, namely three-level converters, are limited by unbalance voltage in the direct current link capacitors. A new control strategy for the selection of the output voltage vectors is proposed in order to improve balance of voltage in the capacitors.

Simulation of Offshore Wind System with Three-Level Converters: HVDC Power Transmission in Cloud Scope

Seixas, M.; Melício, R.; Mendes, V.M.F.; Collares-Pereira, M.; Dos Santos, M. P.
Fonte: IFIP International Federation for Information Processing Publicador: IFIP International Federation for Information Processing
Tipo: Parte de Livro
ENG
Relevância na Pesquisa
86.01%
This paper is on a simulation for offshore wind systems in deep water under cloud scope. The system is equipped with a permanent magnet synchronous generator and a full-power three-level converter, converting the electric energy at variable frequency in one at constant frequency. The control strategies for the three-level are based on proportional integral controllers. The electric energy is injected through a HVDC transmission submarine cable into the grid. The drive train is modeled by a three-mass model taking into account the resistant stiffness torque, structure and tower in the deep water due to the moving surface elevation. Conclusions are taken on the influence of the moving surface on the energy conversion.

Closed loop control of a cascaded multi-level converter to minimize harmonic distortion

Souhan, Brian E.
Fonte: Monterey, California. Naval Postgraduate School Publicador: Monterey, California. Naval Postgraduate School
Tipo: Tese de Doutorado
Relevância na Pesquisa
45.99%
As the United States Navy moves toward the all-electric ship, the need for a robust, high fidelity inverter for propulsion motors becomes mandatory. Military vessels require high power converters capable of producing nearly sinusoidal outputs to prevent torque pulsations and electrical noise that can compromise the mission location. This thesis presents a hybrid pulse-width-modulated controller for a 3x3 Cascaded Multi-Level Converter (CMLC). Ancillary results include a simple technique for extracting the reference sine wave from an independent bulk converter and implementing a synchronization technique that coordinates a space vector modulation controller with the switching pattern of a bulk inverter. The algorithms were tested on CMLC hardware that resides in the Naval Postgraduate School Power Systems Laboratory, and the results were compared with a sine-triangle pulse width modulation algorithm. The controller and converter were used to power a quarter-horsepower three-phase induction motor.

A galvanically isolated power converter module for DC Zonal Electric Distribution Systems

Sarar, Stephen F.
Fonte: Monterey, California. Naval Postgraduate School Publicador: Monterey, California. Naval Postgraduate School
Tipo: Tese de Doutorado
Relevância na Pesquisa
25.96%
The United States Navy is currently in a state of transition from mechanical to electric propulsion. Future warships, such as the new destroyer class, will contain an Integrated Power System (IPS) that provides power to all propulsion and ship service loads. These warships will likely have a dramatic increase in the number of power electronic loads, both AC and DC. For ship service loads, a DC Zonal Electric Distribution System (DCZEDS) will likely be used. DCZEDS requires a device that provides galvanic isolation between the feeder buses and the zones to prevent fault propagation between zones. For DCZEDS to be practical, DC-DC converters that provide galvanic isolation with an efficiency and reliability approaching that of existing low frequency AC isolation transformers must be placed between the feeder buses and the zones. This thesis examines the construction and operation of a prototype galvanically isolated DC-DC converter using commercial-off-the-shelf parts. The converter uses a single-phase high-frequency transformer link to provide galvanic isolation. This work shows that this converter topology is reliable enough to be used in an IPS. A three-phase solution using this topology can provide sufficient power density at the megawatt level...

Conversão eólica offshore ligada à rede elétrica: modelação e simulação

Seixas, Mafalda Maria Morais
Fonte: Universidade de Évora Publicador: Universidade de Évora
Tipo: Tese de Doutorado
POR
Relevância na Pesquisa
26.09%
A tese incide sobre a modelação e simulação de um sistema de conversão de energia eólica offshore com ligação à rede elétrica por transmissão de energia elétrica estudada quer em corrente alternada quer em corrente contínua, no contexto atual de reestruturação do setor elétrico, e integrando a dinâmica relevante. Além da transmissão de energia elétrica, o sistema é constituído por uma plataforma flutuante semissubmersível; uma turbina eólica de velocidade variável; um sistema de transmissão de energia mecânica cuja dinâmica é descrita respetivamente por uma, duas, três ou cinco massas girantes; um gerador síncrono com excitação assegurada por meio de ímanes permanentes; um conversor eletrónico de energia, descrito respetivamente por um conversor de dois níveis ou por um conversor multinível na configuração de díodos de ligação múltipla de três, de quatro, de cinco ou de p níveis. O controlo do sistema utiliza o modo de deslizamento associado com a modulação PWM por vetores espaciais e controladores PI, ditos de clássicos, ou controladores PI de ordem fracionária. Os comportamentos que advêm do facto da energia eólica ser uma fonte de energia variável, com intermitência, assim como...

Design, construction and testing of a reduced-scale cascaded multi-level converter

Crowe, Robert A.
Fonte: Monterey, California. Naval Postgraduate School Publicador: Monterey, California. Naval Postgraduate School
Tipo: Tese de Doutorado Formato: xvi, 127 p. : ill. (some col.) ;
Relevância na Pesquisa
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Approved for public release; distribution is unlimited; The main focus in the design of the next generation combatant, DD(X), is the US Navy's proposed Integrated Power System (IPS) which includes an all-electric propulsion drive system. The reduction of current waveform harmonics is critical in combatant propulsion systems such as the IPS. One method of reducing the current harmonics is to utilize a multilevel converter topology. The multi-level converter, as compared to a standard converter, features low dv/dt losses and low switching losses. This thesis examines the design, construction and testing of two multi-level converters operated in tandem, called a Cascaded Multi-Level Converter (CMLC). A digital logic switching circuit is designed and constructed to control the CMLC during the operational testing phase. The CMLC is demonstrated in a three-phase high-voltage configuration with 178.5 V zero-to-peak voltage, 2.10 A zero-to-peak current achieved using an R-L load.; Lieutenant Commander, United States Navy

Hardware-in-the-Loop control of a cascaded multi-level converter

Barlow, Jacob L.
Fonte: Monterey, California. Naval Postgraduate School Publicador: Monterey, California. Naval Postgraduate School
Tipo: Tese de Doutorado Formato: xvi, 65 p. : ill. ;
Relevância na Pesquisa
45.94%
Approved for public release; distribution is unlimited; Next-generation U.S. Navy destroyers, known as DD(X), will use electric drive motors to meet their propulsion needs instead of the traditional mechanical drives. The use of electric drive motors in naval vessels has spurred the development of high power converters. This thesis examines the feasibility of using an advanced control algorithm known as Sine-triangle Pulse Width Modulation (SPWM) in combination with a Cascaded Multi-Level Converter (CMLC) in order to meet the U.S. Navy's strict requirements. The SPWM control algorithm was designed in Simulink and experimentally tested on a CMLC previously constructed at the Naval Postgraduate School. The controller and converter successfully powered a quarter horsepower three-phase induction motor.; Ensign, United States Navy

SINGLE STAGE POWER FACTOR CORRECTED THREE-LEVEL RESONANT CONVERTERS

Agamy, Mohammed S.
Fonte: Quens University Publicador: Quens University
Tipo: Tese de Doutorado Formato: 7595333 bytes; application/pdf
EN; EN
Relevância na Pesquisa
65.98%
In this thesis, a new approach for single-stage power factor correction converters is proposed to increase their power ratings to be in the multiple kilowatts levels. The proposed techniques are based on the utilization of modified three-level resonant converter topologies. These topologies provide low component stresses, high frequency operation, zero voltage switching, applicability under a wide range of input and output conditions as well as added control flexibility. The proposed control algorithms are based on a combination of variable frequency and asymmetrical pulse width modulation control or variable frequency and phase shift modulation control. In either case, the variable frequency control is used to tightly regulate the output voltage, whereas, pulse width or phase shift modulation is used to regulate the dc-bus voltage as well as the input power factor. New converter topologies, their operation and steady state and dynamic analyses are presented in details. A modelling approach based on average multiple frequency methods is also proposed. This approach leads to the development of a full order state space model with the two control variables explicitly separated allowing a better controller design. The model can be used either at high level of detail expressing the non-linearities of the system or it can readily be simplified to a linear decoupled model for approximate solutions. Finally...

Three-phase three-level current-source converter for EVs fast battery charging systems

Monteiro, Vítor Duarte Fernandes; Exposto, Bruno Fernandes; Pinto, J. G.; Sepúlveda, M. J.; Meléndez, Andrés A. Nogueiras; Afonso, João L.
Fonte: Institute of Electrical and Electronics Engineers Publicador: Institute of Electrical and Electronics Engineers
Tipo: Artigo de Revista Científica
Publicado em /03/2015 ENG
Relevância na Pesquisa
56.11%
This paper presents a three-phase three-level fast battery charger for electric vehicles (EVs) based in a current-source converter (CSC). Compared with the traditional voltage-source converters used for fast battery chargers, the CSC can be seen as a natural buck-type converter, i.e., the output voltage can assume a wide range of values, which varies between zero and the maximum instantaneous value of the power grid phase-to-phase voltage. Moreover, using the CSC it is not necessary to use a dc-dc back-end converter in the battery side, and it is also possible to control the grid current in order to obtain a sinusoidal waveform, and in phase with the power grid voltage (unitary power factor). Along the paper is described in detail the proposed CSC for EVs fast battery charging systems: the circuit topology, the power control theory, the current control strategy and the grid synchronization algorithm. Several simulation results of the EV fast battery charger operating with a maximum power of 50 kW are presented.

Simulation of rectifier voltage malfunction on OWECS, four-level converter, HVDC light link: Smart grid context tool

Melicio, Rui
Fonte: Energy Conversion and Management-Elsevier Publicador: Energy Conversion and Management-Elsevier
Tipo: Artigo de Revista Científica
ENG
Relevância na Pesquisa
55.97%
This paper presents a model for the simulation of an offshore wind system having a rectifier input voltage malfunction at one phase. The offshore wind system model comprises a variable-speed wind turbine supported on a floating platform, equipped with a permanent magnet synchronous generator using full-power four-level neutral point clamped converter. The link from the offshore floating platform to the onshore electrical grid is done through a light high voltage direct current submarine cable. The drive train is modeled by a three-mass model. Considerations about the smart grid context are offered for the use of the model in such a context. The rectifier voltage malfunction domino effect is presented as a case study to show capabilities of the model.

Simulation of a rectifier malfunction on an offshore wind system with HVDC transmission

Melicio, Rui
Fonte: IEEE International Conference on Industrial Technology — ICIT 2015 Publicador: IEEE International Conference on Industrial Technology — ICIT 2015
Tipo: Artigo de Revista Científica
ENG
Relevância na Pesquisa
65.94%
A new integrated mathematical model for the simulation of an offshore wind system having a rectifier input voltage malfunction at one phase is presented in this paper. The mathematical model considers an offshore variable-speed wind turbine on a floating platform, equipped with a permanent magnet synchronous generator using full-power three-level converter to inject energy into the electric network, through a high voltage direct current transmission submarine cable. The model for the drive train is a discrete three mass, incorporating the dynamic of the moving surface. A case study is presented to access conclusion about the malfunction.

Simulation of a rectifier malfunction on a offshore wind system with HVDC transmission

Seixas, Mafalda; Melício, R.; Mendes, V. M. F.; Couto, Carlos
Fonte: IEEE Publicador: IEEE
Tipo: Conferência ou Objeto de Conferência
Publicado em 19/03/2015 ENG
Relevância na Pesquisa
65.94%
A new integrated mathematical model for the simulation of an offshore wind system having a rectifier input voltage malfunction at one phase is presented in this paper. The mathematical model considers an offshore variable-speed wind turbine on a floating platform, equipped with a permanent magnet synchronous generator using full-power three-level converter to inject energy into the electric network, through a high voltage direct current transmission submarine cable. The model for the drive train is a discrete three mass, incorporating the dynamic of the moving surface. A case study is presented to access conclusion about the malfunction.; Fundação Ciência e Tecnologia, through IDMEC/LAETA, Instituto Superior Técnico, Universidade de Lisboa

A modified harmonic elimination method with a wide range of modulation indices for multi-level inverter with unequal DC-sources

Hosseini Aghdam,M.G.; Fathi,S.H.; Gharehpetian,G.B.
Fonte: Latin American applied research Publicador: Latin American applied research
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/01/2009 EN
Relevância na Pesquisa
35.78%
This paper presents a novel modulation technique applied in multi-level inverters with unequal DC sources suitable for wide range of modulation indices. This method considers all the possible switching schemes assuming that the power devices in the different converter modulus can turn ON/OFF up to twice per period. Also, a unified approach using Homotopy algorithm is presented to solve the harmonic elimination equations for all various switching schemes. A three-phase seven-level Y-connected cascaded inverter is modeled in this paper. Experimental results indicate that the proposed technique is effective and efficient for harmonic elimination in multi-level inverter with unequal DC sources and the theoretical results are well validated.