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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
11

Adoção de inovações na indústria automotiva: modelo conceitual e aplicação para sistemas semiativos de amortecimento / Innovation adoption in the automotive industry: conceptual model and application for semiactive damping systems

Silveira Junior, Luiz Antonio Bloem da 12 December 2018 (has links)
A centenária indústria automotiva está passando por profundas transformações nos seus modelos de negócio, processos de desenvolvimento em produto e de produção. Inovações tais como veículos autônomos, transporte compartilhado, células de combustível, entre outras, apresentam-se aos estrategistas das montadoras como alternativas para gerar um diferencial competitivo e garantir a sobrevivência das empresas. Assim sendo, o entendimento dos mecanismos e fatores que influenciam na decisão de adoção de inovações em produto pelas montadoras é um tema relevante para a academia. Artigos sobre adoção de inovação em produto pelas organizações da indústria automotiva não são comuns na literatura, e quando realizados concentram-se no estudo de tecnologias de propulsão alternativa. Este estudo propõe, a partir de uma ampla revisão sistemática da literatura disponível sobre adoção de inovações pelas organizações, um modelo teórico contendo dimensões e fatores de influência na adoção de inovações em produto pelas montadoras de veículos, aplicando o modelo a um componente específico do automóvel, os chamados sistemas semiativos de amortecimento ou \'amortecedores inteligentes\'. Um diferencial do modelo conceitual desenvolvido foi a introdução da dimensão \'gestão da inovação\', analisando diversos fatores relacionados à estratégia tecnológica da montadora. A aplicação deste modelo foi realizada utilizando a metodologia de pesquisa qualitativa básica, por meio de entrevistas com funcionários de montadoras e fabricantes de sistemas de suspensão e amortecedores estabelecidos no mercado automotivo brasileiro. Uma pesquisa adicional foi realizada com o objetivo de identificar de que maneira a importância relativa entre os fatores que influem na adoção de inovações em produto pelas montadoras de veículos muda entre um país desenvolvido (EUA) e outro em desenvolvimento (Brasil). Dessa forma, o modelo conceitual desenvolvido foi aplicado por meio de entrevistas realizadas com funcionários de empresas do segmento automotivo estabelecidas no mercado dos EUA. As análises dos resultados permitiram identificar os fatores de maior influência na adoção da inovação em estudo pelas montadoras, bem como os fatores de menor influência. Análises comparativas foram realizadas entre estes fatores, para discutir as razões das semelhanças e diferenças entre eles. Esta tese produziu três artigos correlacionados entre si, o primeiro denominado Adoção de inovações em produto pelas organizações: Uma revisão sistemática de literatura. O segundo artigo foi intitulado como Adoção de inovações em produto na indústria automotiva: Modelo conceitual e aplicação para sistemas semiativos de amortecimento. O artigo Adoção de inovações em produto na indústria automotiva: Um estudo comparativo entre Brasil e EUA é o terceiro e último da tese. Estudos comparando a influência de fatores de adoção de inovação em produto pelas organizações foram realizados em outras áreas da tecnologia, porém artigos com comparações internacionais entre estes fatores não são comuns na literatura. Nenhum estudo sobre adoção de sistemas semiativos de amortecimento ou \'amortecedores inteligentes\' foi identificado na revisão de literatura realizada, o que evidencia o ineditismo deste trabalho de pesquisa. / The centenary automotive industry has gone through significant transformations in its business models, product development and production processes. Innovations like autonomous vehicles, transportation sharing, fuel cells, among others, show themselves as alternatives to create a competitive differential and assure companies survival. Therefore, the understanding of mechanisms and factors that influence automaker\'s decision to adopt product innovations is a relevant issue for the academy. Papers about product innovation adoption by organizations in the automotive industry are not common in the literature. When made, they focus mostly on the study of alternative propulsion technologies. This research proposes a theoretical model comprising dimensions and factors influencing product innovation adoption by automakers based on a broad literature systematic analysis about organizational innovation adoption. This model was applied to a specific automotive component, the so-called semi active damping systems or \"smart shock absorbers.\" The conceptual model presents the unpublished dimension \"innovation management\", which analyses several factors related to the automakers technological strategy. This research used basic qualitative analysis methodology and performed interviews with employees from automakers and suspension system manufacturers settled in the Brazilian automotive market. An extra research aimed to identify the way the relative importance between the factors that influence in the product innovation adoption by the automakers changes from a developed country (USA) and another country in development (Brazil). Interviews with employees from automotive companies settled in the USA market applied the conceptual model. The result of the analysis allowed the identification of the most influencing factors in the adoption of the product innovation by automakers, as well the less influencing factors. Comparative analyses between these factors were made in order to discuss the reasons of similarities and differences between them. This dissertation produced three correlated papers se, the first one is \"Product innovation adoption by organizations: A systematic literature review.\" The second one is \"Product innovation adoption in the automotive industry: Conceptual model and application for semi active damping systems.\" The third and last one of this dissertation is \"Product innovation adoption in the automotive industry: A comparative study between Brazil and USA.\" There are papers comparing the factors influencing product innovation adoption by organizations in other technology fields, but international comparisons between these factors are not common in literature. This research found no paper about semi active damping systems (\"smart shock absorbers\") in the literature review, which evidences the brand new characteristic of this dissertation.
12

Analysis and Control Aspects of a PMSynRel Drive in a Hybrid Electric Vehicle Application

Zhao, Shuang January 2013 (has links)
This thesis deals withmodeling and control of an electric drive equipped with a permanentmagnet assisted synchronous reluctance (PMSynRel) machine for a plug-in hybrid electric vehicle application. In the first part of the thesis, a special use of the PMSynRel machine in consideration, known as an integrated charger concept, is investigated. The integrated charger feature allows using the PMSynRel machine as a part of the vehicle’s on-board charging system when charging the battery from the grid. A finite-element based analysis is performed providing important insights into the machine operation during the charging process. Dynamic models are developed that facilitate the controller development and the estimation of the efficiency during charging. In the second part of the thesis, position sensorless control of the PMSynRel drive when applied in an automotive application is considered and analyzed thoroughly. First, a fundamental-excitation based rotor-position estimation technique is investigated. The study shows that the impact of current dynamics on the resulting torque dynamics has to be considered in some very demanding applications. Second, focus is put on signalinjection based sensorless control methods. Impacts of nonlinearities, such as magnetic saturation, cross-saturation and inductance spatial harmonics, on sensorless control performance are investigated and methods to improve the sensorless control quality are summarized and presented. An approach to determine the feasible region for operating sensorless at low-speeds without directly measuring the differential inductances is proposed. For the PMSynRel drive in consideration, the achievable maximum torque is limited when operating sensorless following the maximum-torque-per-ampere (MTPA) current reference trajectory at low-speeds. An optimization approach is therefore proposed which extends the output torque when operating sensorless while still maintaining a relatively high efficiency. To initialize the sensorless control correctly from standstill, the impact of the saturated magnetic bridges in the rotor is also investigated. Finally, torsional drive-train oscillations and active damping schemes are considered. An off-vehicle setup for implementing and evaluating different active damping schemes is proposed. Of particular interest for sensorless operation in automotive applications, the impact of slow speed estimation on the possibility to achieve good active damping control is investigated and a design approach that allows the implementation of an active damping scheme using estimated speed is suggested. / <p>QC 20140114</p>
13

Sistema de controle digital para retificador trifásico a quatro fios com filtro LCL / Digital control system for three-phase four-wire rectifier with LCL filter

Nishioka, Julio Kendi 25 August 2011 (has links)
Made available in DSpace on 2016-12-12T17:38:38Z (GMT). No. of bitstreams: 1 JULIO KENDI NISHIOKA.pdf: 8294340 bytes, checksum: 28a4178bb0ec559b2db43a1aa6676188 (MD5) Previous issue date: 2011-08-25 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / This dissertation proposes a digital control system for a three-phase four-wire high input power factor PWM rectifier with LCL filter. The proposed control system includes an inner control loop for active damping of the LCL filter peak resonance, which uses a lead-lag compensator. In addition, the control system presents an independent current loop for each rectifier phase, which employs resonant compensators tuned at the fundamental frequency of the utility grid voltage. Finally, other two outer loops are used to maintain the voltages across the dc bus capacitors regulated and balanced. This work also proposes a design methodology to obtain the parameter of the LCL filter, which is based on maximum harmonic currents allowed by technical standards and on the minimization of the reactive energy of the LCL filter capacitors. Simulation and experimental results are presented to validate the developed analysis and demonstrate the performance of the proposed controllers. / Esta Dissertação de Mestrado propõe um sistema de controle digital para um retificador PWM trifásico a quatro fios com filtro LCL e elevado fator de potência de entrada. O sistema de controle proposto inclui uma malha interna de amortecimento ativo do pico de ressonância do filtro LCL, fazendo uso de um compensador em avanço. Além da malha de amortecimento ativo, o sistema de controle apresenta uma malha de corrente independente para cada fase do retificador, as quais empregam compensadores ressonantes sintonizados na frequência fundamental da tensão de entrada. Por fim, outras duas malhas externas são utilizadas para manter as tensões dos capacitores que compõem o barramento CC reguladas e equilibradas. Este trabalho também propõe uma metodologia de projeto para os parâmetros do filtro LCL, a qual é baseada nos limites máximos de harmônicos de corrente permitidos pelas normas e na minimização da energia reativa do capacitor do filtro LCL. Resultados de simulação e experimentais são apresentados para validar as análises desenvolvidas e demonstrar o desempenho dos controladores propostos.
14

Chatter reduction through active vibration damping

Ganguli, ABHIJIT 24 November 2005 (has links)
The aim of the thesis is to propose active damping as a potential control strategy for chatter instability in machine tools.<p>The regenerative process theory explains chatter as a closed loop interaction between the structural dynamics and the cutting process. This is considered to be the most dominant reason behind machine tool chatter although other instability causing mechanisms exist.<p>The stability lobe diagram provides a quantitative idea of the limits of stable machining in terms of two physical parameters: the width of contact between tool and the workpiece, called the width of cut and the speed of rotation of the spindle. It is found that the minimum value of the stability limit is proportional to the structural damping ratio for turning operations. This important finding provides the motivation of influencing the structural dynamics by active damping to enhance stability limits of a machining operation.<p>A direct implementation of active damping in an industrial environment may be difficult. So an intermediate step of testing the strategy in a laboratory setup, without conducting real cutting is proposed. Two mechatronic "Hardware in the Loop" simulators for chatter in turning and milling are presented, which simulate regenerative chatter experimentally without conducting real cutting tests. A simple cantilever beam, representing the MDOF dynamics of<p>the machine tool structure constitutes the basic hardware part and the cutting process is simulated in real time on a DSP board. The values of the cutting parameters such as spindle speed and the axial width of cut can be changed on the DSP board and the closed loop interaction between the structure and the cutting process can be led to instability.<p><p>The demonstrators are then used as test beds to investigate the efficiency of active damping, as a potential chatter stabilization strategy. Active damping is easy to implement, robust and does not require a very detailed model of the structure for proper functioning, provided a collocated sensor and actuator configuration is followed. The idea of active damping is currently being implemented in the industry in various metal cutting machines as part of the European Union funded SMARTOOL project (www.smartool.org), intended to propose smart chatter control technologies in machining operations. / Doctorat en sciences appliquées / info:eu-repo/semantics/nonPublished
15

Semi-Active Damping for an Intelligent Adaptive Ankle Prosthesis

Lapre, Andrew K 01 January 2012 (has links) (PDF)
Modern lower limb prostheses are devices that replace missing limbs, making it possible for lower limb amputees to walk again. Most commercially available prosthetic limbs lack intelligence and passive adaptive capabilities, and none available can adapt on a step by step basis. Often, amputees experience a loss of terrain adaptability as well as stability, leaving the amputee with a severely altered gait. This work is focused on the development of a semi-active damping system for use in intelligent terrain adaptive ankle prostheses. The system designed consists of an optimized hydraulic cylinder with an electronic servo valve which throttles the hydraulic fluid flowing between the cylinder’s chambers, acting on the prosthesis joint with a moment arm in series with a carbon spring foot. This provides the capability to absorb energy during the amputees gait cycle in a controlled manner, effectively allowing the passive dynamic response to be greatly altered continuously by leveraging a small energy source. A virtual simulation of an amputee gait cycle with the adaptive semi-active ankle design revealed the potential to replicate adaptive abilities of the human ankle. The results showed very similarly that irregularities in amputee biomechanics can be greatly compensated for using semi-active damping.
16

Subsystem Design in Aircraft Power Distribution Systems using Optimization

Chandrasekaran, Sriram 26 June 2000 (has links)
The research reported in this dissertation focuses on the development of optimization tools for the design of subsystems in a modern aircraft power distribution system. The baseline power distribution system is built around a 270V DC bus. One of the distinguishing features of this power distribution system is the presence of regenerative power from the electrically driven flight control actuators and structurally integrated smart actuators back to the DC bus. The key electrical components of the power distribution system are bidirectional switching power converters, which convert, control and condition electrical power between the sources and the loads. The dissertation is divided into three parts. Part I deals with the formulation of an optimization problem for a sample system consisting of a regulated DC-DC buck converter preceded by an input filter. The individual subsystems are optimized first followed by the integrated optimization of the sample system. It is shown that the integrated optimization provides better results than that obtained by integrating the individually optimized systems. Part II presents a detailed study of piezoelectric actuators. This study includes modeling, optimization of the drive amplifier and the development of a current control law for piezoelectric actuators coupled to a simple mechanical structure. Linear and nonlinear methods to study subsystem interaction and stability are studied in Part III. A multivariable impedance ratio criterion applicable to three phase systems is proposed. Bifurcation methods are used to obtain global stability characteristics of interconnected systems. The application of a nonlinear design methodology, widely used in power systems, to incrementally improve the robustness of a system to Hopf bifurcation instability is discussed. / Ph. D.
17

Repetitive Control Of A Three-phase Uninterruptible Power Supply With Isolation Transformer

Cetinkaya, Suleyman 01 January 2007 (has links) (PDF)
A repetitive control method for output voltage control of a three phase uninterruptible power supply (UPS) with isolation transformer is investigated. In the method voltage control loop is employed in the stationary dq frame. The controller eliminates the periodic errors on the output voltages due to inverter voltage nonlinearity and load disturbances. The controller design and implementation details are given. The controller is implemented on a 5-kVA UPS prototype which is constructed in laboratory. Linear and nonlinear loads for balanced and unbalanced load operating conditions are considered. The steady-state and dynamic performance of the control method are investigated in detail. The theory of the control strategy is verified by means of simulations and experiments.
18

Output Voltage Control Of A Four-leg Inverter Based Three-phase Ups By Means Of Stationary Frame Resonant Filter Banks

Demirkutlu, Eyyup 01 January 2007 (has links) (PDF)
A method for high performance output voltage control of a four-leg inverter based three-phase transformerless UPS is proposed. Voltage control loop is employed and the method employs stationary frame resonant filter controllers for the fundamental and harmonic frequency components. A capacitor current feedback loop provides active damping and enhances the output voltage dynamic performance. The controller design and implementation details are given. Linear and nonlinear loads for balanced and unbalanced load operating conditions are considered. The steadystate and dynamic performance of the UPS are investigated in detail. A scalar PWM method with implementation simplicity and high performance is proposed and implemented. The control and PWM methods are proven by means of theory, simulations, and experiments.
19

Controle robusto de inversores VSI com filtro LCL aplicados a geração distribuída, com controle da injeção de potências ativa e reativa na rede de distribuição em baixa tensão e capacidade de operação ilhada em ambiente de microrredes / Robust control of voltage source inverters with LCL filters suitable for distributed generation, with control of the injection of active and reactive power on the low voltage distribution network and capability to operate in islanded mode in microgrid scenario

Pena, José Carlos Ugaz [UNESP] 02 June 2016 (has links)
Submitted by JOSÉ CARLOS UGAZ PEÑA null (josecarlos84@gmail.com) on 2016-06-20T13:29:30Z No. of bitstreams: 1 Tese_JoseCarlosPena_PPGEE.pdf: 9650212 bytes, checksum: 77b105d009c0b473cbc424e681ebe9a5 (MD5) / Approved for entry into archive by Ana Paula Grisoto (grisotoana@reitoria.unesp.br) on 2016-06-22T13:10:00Z (GMT) No. of bitstreams: 1 pena_jcu_dr_ilha.pdf: 9650212 bytes, checksum: 77b105d009c0b473cbc424e681ebe9a5 (MD5) / Made available in DSpace on 2016-06-22T13:10:00Z (GMT). No. of bitstreams: 1 pena_jcu_dr_ilha.pdf: 9650212 bytes, checksum: 77b105d009c0b473cbc424e681ebe9a5 (MD5) Previous issue date: 2016-06-02 / Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) / Os inversores fonte de tensão com filtro de saída LCL (VSI+LCL) são amplamente utilizados em sistemas de geração distribuída. Nestas aplicações o sistema é controlado como uma fonte de corrente, no entanto, há a possibilidade de controlar o conjunto como uma fonte de tensão. Desta forma, a mencionada configuração pode ser utilizada em geração distribuída no ambiente de microrredes onde os sistemas, monofásicos ou trifásicos, devem operar conectados à rede de distribuição elétrica com controle das potências injetadas (ativa e reativa) e serem capazes de, em ausência da rede, passar a operar no modo autônomo. Ainda, após o restabelecimento da rede, o controle deve levar o sistema a operar novamente no modo conectado. Sendo as transições realizadas sem transientes que possam danificar qualquer componente do sistema. O filtro LCL, de terceira ordem, caracteriza um comportamento ressonante que pode comprometer a estabilidade do sistema. Para resolver esta situação, diversas técnicas ativas e passivas são aplicadas. Para aplicações de baixa potência, preferem-se as técnicas passivas de amortecimento devido a sua simplicidade e baixo custo, porém estas implicam em perdas adicionais. Já as técnicas ativas de amortecimento, consideram procedimentos de controle para atenuar a ressonância, e, portanto, não adicionam perdas, porém, sua realização requer da realimentação de variáveis adicionais elevando assim o custo do sistema. Todavia, mesmo que aplicáveis a ambos os modos de operação, as técnicas de amortecimento disponíveis na literatura consideram apenas um modo de operação. O presente trabalho de doutorado explora a possibilidade de controlar sistemas VSI+LCL, monofásicos e trifásicos, em ambos os modos de operação, com atenção a objetivos específicos em cada modo e transições suaves entre estes. Assim, são apresentadas duas estratégias de controle. A primeira estratégia considera o amortecimento da ressonância por técnicas passivas, mediante a utilização de um ramo de amortecimento de segunda ordem, projetado para garantir o efeito desejado em ambos os modos de operação e simplificar a dinâmica do sistema a fim de facilitar o projeto dos controladores, abordagem não utilizada nos métodos conhecidos na literatura. Logo, o sistema amortecido é controlado em uma configuração de duas malhas, controlando a corrente injetada mediante a tensão no capacitor. A segunda estratégia proposta considera a utilização de controladores por realimentação de estados em tempo discreto, sintetizados mediante desigualdades matriciais lineares, para simultaneamente, realizar ativamente o amortecimento da ressonância e atender os objetivos de controle em ambos os modos de operação. Ambas as estratégias propostas consideram controladores ressonantes com o objetivo de rastrear sinais senoidais de referência com erro nulo e suprimir componentes harmônicos de baixa ordem na corrente de saída. Ainda, os controladores são projetados considerando a necessidade de garantir a estabilidade robusta do sistema, isto é, frente a perturbações externas (tais como variações na carga local, oscilações na tensão do barramento CC ou distúrbios na rede) e às variações em parâmetros do sistema, como a indutância de rede. As propostas são apresentadas em detalhe, incluindo os procedimentos de projeto assim como critérios para a geração e coordenação dos sinais de controle e referência. As estratégias propostas são avaliadas experimentalmente sendo os resultados obtidos discutidos e analisados considerando-se as respectivas normas para os casos de operação conectada e ilhada. / The voltage source inverter utilization with LCL filters (VSI+LCL) is extended in Distributed Electrical Energy Systems. In these applications, the system is controlled as a current source, however, it can also be controlled as a voltage source. Hence, this configuration is suitable for microgrids environment. In this scenario, the system should operate connected to utility grid with control of the supplied power (active or reactive) and also be capable, in case of grid absence, to operate in islanded mode. Then, if the grid is reestablished, system should be reconnected to grid. Moreover, these transitions should be smooth, with no hazardous transients. The third order filter leads to a resonant behavior that can compromise the system stability. In order to overcome this limitation, passive and active damping methods are used. In low power applications, passive damping methods are preferred due to their simplicity and low. Nevertheless, these methods lead to additional losses. On the other hand, active damping methods consider the feedback of additional variables in order to damp the resonance in closed loop, with no additional losses. This implies additional sensors, thus increasing the overall cost. Despite their effectiveness to damp the resonance in both autonomous and grid connected applications, the most of the damping methods are usually designed only for a specific operation mode. This work explores the possibility to control VSI+LCL systems, single and three-phase, in both operation modes, attending to specific goals in each one, and with smooth transitions between them. For that purpose, two control strategies are proposed. The first one considers passive damping methods, by using a second order damping branch which is designed in order to guarantee the desired effect in both operation modes, thus simplifying the system dynamics in order to ease the control. This approach is not known in the literature. Then, the damped system is controlled in a two loop strategy, where the output current is controlled by means of the capacitor voltage. The second strategy considers the utilization of discrete time state-feedback controllers, synthesized by Linear Matrix Inequalities, in order to simultaneously achieve the active damping and the control goals for both operation modes. The proposed strategies use resonant controllers in order to achieve the tracking of sinusoidal references and to suppress low order harmonics in the output current. Moreover, controllers are designed to achieve robust stability of the system, thus, even in front of external disturbances (such as local load variations, DC bus oscillations or grid disturbances) and variation on system parameters, such as the grid inductance. The two introduced strategies are detailed including the design procedure and the criterion to generate and coordinate the reference and control signals. The two proposed strategies were experimentally verified. The results were analyzed and compared to the requirements imposed by the related standards for both modes of operation. / CNPq: 141757/2012-4
20

Controle robusto de inversores VSI com filtro LCL aplicados a geração distribuída, com controle da injeção de potências ativa e reativa na rede de distribuição em baixa tensão e capacidade de operação ilhada em ambiente de microrredes /

Pena, José Carlos Ugaz January 2016 (has links)
Orientador: Carlos Alberto Canesin / Resumo: Os inversores fonte de tensão com filtro de saída LCL (VSI+LCL) são amplamente utilizados em sistemas de geração distribuída. Nestas aplicações o sistema é controlado como uma fonte de corrente, no entanto, há a possibilidade de controlar o conjunto como uma fonte de tensão. Desta forma, a mencionada configuração pode ser utilizada em geração distribuída no ambiente de microrredes onde os sistemas, monofásicos ou trifásicos, devem operar conectados à rede de distribuição elétrica com controle das potências injetadas (ativa e reativa) e serem capazes de, em ausência da rede, passar a operar no modo autônomo. Ainda, após o restabelecimento da rede, o controle deve levar o sistema a operar novamente no modo conectado. Sendo as transições realizadas sem transientes que possam danificar qualquer componente do sistema. O filtro LCL, de terceira ordem, caracteriza um comportamento ressonante que pode comprometer a estabilidade do sistema. Para resolver esta situação, diversas técnicas ativas e passivas são aplicadas. Para aplicações de baixa potência, preferem-se as técnicas passivas de amortecimento devido a sua simplicidade e baixo custo, porém estas implicam em perdas adicionais. Já as técnicas ativas de amortecimento, consideram procedimentos de controle para atenuar a ressonância, e, portanto, não adicionam perdas, porém, sua realização requer da realimentação de variáveis adicionais elevando assim o custo do sistema. Todavia, mesmo que aplicáveis a ambos os modos de operação,... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: The voltage source inverter utilization with LCL filters (VSI+LCL) is extended in Distributed Electrical Energy Systems. In these applications, the system is controlled as a current source, however, it can also be controlled as a voltage source. Hence, this configuration is suitable for microgrids environment. In this scenario, the system should operate connected to utility grid with control of the supplied power (active or reactive) and also be capable, in case of grid absence, to operate in islanded mode. Then, if the grid is reestablished, system should be reconnected to grid. Moreover, these transitions should be smooth, with no hazardous transients. The third order filter leads to a resonant behavior that can compromise the system stability. In order to overcome this limitation, passive and active damping methods are used. In low power applications, passive damping methods are preferred due to their simplicity and low. Nevertheless, these methods lead to additional losses. On the other hand, active damping methods consider the feedback of additional variables in order to damp the resonance in closed loop, with no additional losses. This implies additional sensors, thus increasing the overall cost. Despite their effectiveness to damp the resonance in both autonomous and grid connected applications, the most of the damping methods are usually designed only for a specific operation mode. This work explores the possibility to control VSI+LCL systems, single and three-phase... (Complete abstract click electronic access below) / Doutor

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