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Modelling and simulation of power electronic systems using a bond graph formalism

Araújo, R.; Leite, V.; Freitas, D.
Fonte: Instituto Politécnico de Bragança Publicador: Instituto Politécnico de Bragança
Tipo: Artigo de Revista Científica
ENG
Relevância na Pesquisa
66.33%
This paper deals with the modelling of power electronic systems using the bond graph formalism. The switching components are modelled using an ideal representation so that a constant topology system is obtained. The purpose of the present contribution is to discuss a technique that combines bond graph energy-flow modelling and signal-flow modelling schemes for simulation and prototyping of signal processing algorithms in power electronics systems. In this paper, we will discuss models of the use of fully-controlled, semi-controlled and non-controlled switches in the field of power static converters. By concept, a simulation environment can be examined at different abstraction or hierarchy levels. The approach in this paper is, accordingly, the formulation of a simulation task at different levels: component level, topology level, functional description and implementation description. The paper concludes with two practical examples of simulation of power electronics systems.

Galerkin finite element method for incompressible thermofluid flows framed within the bond graph theory

BALIÑO, Jorge Luis
Fonte: ELSEVIER SCIENCE BV Publicador: ELSEVIER SCIENCE BV
Tipo: Artigo de Revista Científica
ENG
Relevância na Pesquisa
56.4%
In this paper a bond graph methodology is used to model incompressible fluid flows with viscous and thermal effects. The distinctive characteristic of these flows is the role of pressure, which does not behave as a state variable but as a function that must act in such a way that the resulting velocity field has divergence zero. Velocity and entropy per unit volume are used as independent variables for a single-phase, single-component flow. Time-dependent nodal values and interpolation functions are introduced to represent the flow field, from which nodal vectors of velocity and entropy are defined as state variables. The system for momentum and continuity equations is coincident with the one obtained by using the Galerkin method for the weak formulation of the problem in finite elements. The integral incompressibility constraint is derived based on the integral conservation of mechanical energy. The weak formulation for thermal energy equation is modeled with true bond graph elements in terms of nodal vectors of temperature and entropy rates, resulting a Petrov-Galerkin method. The resulting bond graph shows the coupling between mechanical and thermal energy domains through the viscous dissipation term. All kind of boundary conditions are handled consistently and can be represented as generalized effort or flow sources. A procedure for causality assignment is derived for the resulting graph...

Análise da dinâmica e da prática do planejamento e controle da produção: uma abordagem combinada de estudo de caso e modelagem de sistemas dinâmicos; Analysis of the dynamics and practice of the production planning and control: an approach combining case study and system dynamics modeling

Sagawa, Juliana Keiko
Fonte: Biblioteca Digitais de Teses e Dissertações da USP Publicador: Biblioteca Digitais de Teses e Dissertações da USP
Tipo: Tese de Doutorado Formato: application/pdf
Publicado em 01/10/2013 PT
Relevância na Pesquisa
46.16%
Os paradigmas de mercado e produção têm-se alterado sensivelmente nos últimos cinquenta anos. Nesse novo contexto, para que as empresas tenham um desempenho competitivo, deve-se considerar fatores como integração, qualidade da informação e incertezas do ambiente. Um dos objetivos principais deste trabalho é analisar as inter-relações entre esses três fatores citados, no âmbito do Planejamento e Controle da Produção (PCP), bem como avaliar seu impacto no desempenho do PCP e da empresa. O desempenho do PCP foi avaliado considerando-se o nível de reprogramações, ou seja, o nível de modificações na programação da produção, e considerando-se o atendimento das metas definidas para os indicadores dessa função. Essa pesquisa qualitativa e descritiva foi feito por meio da metodologia de estudo de casos múltiplos. Como resultados, foram observadas evidências da existência de relações positivas entre os constructos analisados, ou seja, integração, incerteza, qualidade da informação e desempenho. Além disso, foram identificados diferentes mecanismos de integração utilizados nas empresas, e foram observadas diferentes causas para as reprogramações. O segundo objetivo principal deste trabalho é o desenvolvimento de um modelo dinâmico para controle da produção de múltiplos produtos...

Modelagem e simulação de redes de gás natural utilizando bond graphs

Koga, Tiago Murbach
Fonte: Florianópolis, SC Publicador: Florianópolis, SC
Tipo: Dissertação de Mestrado Formato: xviii, 139 f.| il., grafs., tabs.
POR
Relevância na Pesquisa
36.01%
Dissertação (mestrado) - Universidade Federal de Santa Catarina, Centro Tecnológico. Programa de Pós-graduação em Engenharia Mecânica; A predição da distribuição de pressão num gasoduto é tão importante quanto a predição do consumo dos clientes. Neste contexto, este trabalho apresenta o desenvolvimento de um modelo dinâmico para determinação da distribuição de pressão em um gasoduto, operando em regime transiente. A modelagem é do tipo de parâmetros concentrados, mais especificamente bond graphs que consiste na combinação de elementos resistivos, indutivos, capacitivos, fontes/sumidouros e juntas, sendo aplicável na análise transiente de sistemas hidráulicos, pneumáticos, mecânicos e elétricos, entre outros. Esse trabalho propõe aplicar esta técnica de modelagem na análise do comportamento de gasodutos, dado que na literatura consultada não se encontraram relatos com esta abordagem. Na teoria de bond graph aplicada a sistemas fluidodinâmicos, o efeito de altura normalmente é desprezível, porém no problema físico em questão o efeito do perfil de relevo tem uma contribuição significativa, por isso se propõe uma maneira mais generalizada para avaliar tais sistemas. Além disso, são também importantes os efeitos de compressibilidade...

Modelagem matemática da tíbia humana usando Bond Graph; Modeling of the human tibia bone using Bond Graph

Rosa, Suélia de Siqueira Rodrigues Fleury; Souza, Êmille Késsy Ferreira de; Urbizagástegui, Pablo Alejandro de Abreu; Peixoto, Luciana Roberta Tenório; Rocha, Adson Ferreira da
Fonte: SBEB - Sociedade Brasileira de Engenharia Biomédica Publicador: SBEB - Sociedade Brasileira de Engenharia Biomédica
Tipo: Artigo de Revista Científica
POR
Relevância na Pesquisa
66.48%
Introdução: Procedimentos cirúrgicos ortopédicos como a osteotomia, em que se realiza o corte da tíbia, são muito comuns e devem ser muito bem executados para que sejam obtidos bons resultados. Nesse cenário, o estudo de como o osso reage ao processo de corte é um tópico relevante de estudos. O objetivo deste trabalho é apresentar um modelo matemático do processo de corte na tíbia humana por uma serra automática, usando o método de Bond Graph. Métodos: Com base em um trabalho anterior, foi desenvolvido um modelo para a força de reação ao corte da serra. Além disso, foi desenvolvido um modelo embasado no método Bond Graph para se determinar a resposta das diversas partes do osso à ação da serra. Foram também realizadas análises no domínio da frequência para se analisar a estabilidade do sistema. Resultados: Foram obtidos e apresentados os resultados das simulações descritas. Os resultados mostraram boa concordância com o comportamento esperado para a força de reação à serra e para a resposta do material ósseo ao corte. Além disso, as análises no domínio da frequência mostraram que o método de modelagem proposto tem características promissoras com relação a estabilidade do sistema. Conclusão: Os resultados sugerem que o método tem bom potencial para ser usado...

Automated Identification and Classification of Stereochemistry: Chirality and Double Bond Stereoisomerism

Leal, João P.; Falcao, Andre O.; Teixeira, Ana L.
Fonte: Universidade de Lisboa Publicador: Universidade de Lisboa
Tipo: Relatório
Publicado em 27/02/2013 ENG
Relevância na Pesquisa
36.2%
Stereoisomers have the same molecular formula and the same atom connectivity and their existence can be related to the presence of different three-dimensional (3D) arrangements. Stereoisomerism is of great importance in many different fields since the molecular properties and biological effects of the stereoisomers are often significantly different. Most drugs for example, are often composed of a single stereoisomer of a compound, and while one of them may have therapeutic effects on the body, another may be toxic. A challenging task is the automatic detection of stereoisomers using line input specifications such as SMILES or InChI since it requires information about group theory (to distinguish stereoisomers using mathematical information about its symmetry), topology and geometry of the molecule. There are several software packages that include modules to handle stereochemistry, especially the ones to name a chemical structure and/or view, edit and generate chemical structure diagrams. However, there is a lack of software capable of automatically analyzing a molecule represented as a graph and generate a classification of the type of isomerism present in a given atom or bond. Considering the importance of stereoisomerism when comparing chemical structures...

Bond Graph modeling of the human esophagus and analysis considering the interference in the fullness of an individual by reducing mechanical esophageal flow

Rosa,Suélia de Siqueira Rodrigues Fleury; Altoé,Mirella Lorrainy
Fonte: SBEB - Sociedade Brasileira de Engenharia Biomédica Publicador: SBEB - Sociedade Brasileira de Engenharia Biomédica
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/09/2013 EN
Relevância na Pesquisa
66.24%
INTRODUCTION: This paper shows a proposal for the mathematical modeling of the human esophagus using Bond Graph formalism and the interference in the satiation of an individual by way of an Esophageal Flow Controller (EFC). Therefore, it was evaluated that there is a significant change in fall time that affects the process of human satiety when the diameter of the esophagus is reduced. METHODS: As a first study, the analysis did not consider all hypothetical influences; only the most important variables were considered. RESULTS: As a result, the order of the final equation was x ∈ ℜ10. Furthermore, the designed model can be classified as linear, established and time invariant. CONCLUSION: The simulation results allow us to conclude that using the EFC in order to reduce the esophageal diameter in the upper esophageal sphincter area of 3cm by 1 cm implies that the system response will be slower; and consequently this reduction will interfere with satiety.

Modelagem matemática da tíbia humana usando Bond Graph

Rosa,Suelia de Siqueira Rodrigues Fleury; Souza,Êmille Kessy Ferreira de; Urbizagástegui,Pablo Alejandro de Abreu; Peixoto,Luciana Roberta Tenório; Rocha,Adson Ferreira da
Fonte: SBEB - Sociedade Brasileira de Engenharia Biomédica Publicador: SBEB - Sociedade Brasileira de Engenharia Biomédica
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/12/2013 PT
Relevância na Pesquisa
66.33%
INTRODUCAO Procedimentos cirúrgicos ortopdicos como a osteotomia, em que se realiza o corte da tíbia, são muito comuns e devem ser muito bem executados para que sejam obtidos bons resultados. Nesse cenário, o estudo de como o osso reage ao processo de corte um tópico relevante de estudos. O objetivo deste trabalho apresentar um modelo matemático do processo de corte na tíbia humana por uma serra automática, usando o mtodo de Bond Graph. MTODOS: Com base em um trabalho anterior, foi desenvolvido um modelo para a força de reação ao corte da serra. Alm disso, foi desenvolvido um modelo embasado no mtodo Bond Graph para se determinar a resposta das diversas partes do osso à ação da serra. Foram tambm realizadas análises no domínio da frequência para se analisar a estabilidade do sistema. RESULTADOS: Foram obtidos e apresentados os resultados das simulações descritas. Os resultados mostraram boa concordância com o comportamento esperado para a força de reação à serra e para a resposta do material ósseo ao corte. Alm disso, as análises no domínio da frequência mostraram que o mtodo de modelagem proposto tem características promissoras com relação a estabilidade do sistema. CONCLUSÃO: Os resultados sugerem que o mtodo tem bom potencial para ser usado...

A bond graph model of the cardiovascular system

Le Rolle, Virginie; Hernandez, Alfredo I.; Richard, Pierre-Yves; Buisson, Jean; Carrault, Guy
Fonte: Springer Publicador: Springer
Tipo: Artigo de Revista Científica
Publicado em //2005 EN
Relevância na Pesquisa
46.08%
The study of the autonomic nervous system (ANS) function has shown to provide useful indicators for risk stratification and early detection on a variety of cardiovascular pathologies. However, data gathered during different tests of the ANS are difficult to analyse, mainly due to the complex mechanisms involved in the autonomic regulation of the cardiovascular system (CVS). Although model-based analysis of ANS data has been already proposed as a way to cope with this complexity, only a few models coupling the main elements involved have been presented in the literature. In this paper, a new model of the CVS, representing the ventricles, the circulatory system and the regulation of the CVS activity by the ANS, is presented. The models of the vascular system and the ventricular activity have been developed using the Bond Graph formalism, as it proposes a unified representation for all energetic domains, facilitating the integration of mechanic and hydraulic phenomena. In order to take into account the electro-mechanical behaviour of both ventricles, an electrophysiologic model of the cardiac action potential, represented by a set of ordinary differential equations, has been integrated. The short-term ANS regulation of heart rate, cardiac contractility and peripheral vasoconstriction is represented by means of continuous transfer functions. These models...

Bond Graph Modeling and Validation of an Energy Regenerative System for Emulsion Pump Tests

Li, Yilei; Zhu, Zhencai; Chen, Guoan
Fonte: Hindawi Publishing Corporation Publicador: Hindawi Publishing Corporation
Tipo: Artigo de Revista Científica
EN
Relevância na Pesquisa
46.33%
The test system for emulsion pump is facing serious challenges due to its huge energy consumption and waste nowadays. To settle this energy issue, a novel energy regenerative system (ERS) for emulsion pump tests is briefly introduced at first. Modeling such an ERS of multienergy domains needs a unified and systematic approach. Bond graph modeling is well suited for this task. The bond graph model of this ERS is developed by first considering the separate components before assembling them together and so is the state-space equation. Both numerical simulation and experiments are carried out to validate the bond graph model of this ERS. Moreover the simulation and experiments results show that this ERS not only satisfies the test requirements, but also could save at least 25% of energy consumption as compared to the original test system, demonstrating that it is a promising method of energy regeneration for emulsion pump tests.

Complementary use of BG and EMR formalisms for multiphysics systems analysis and control

CHIKHAOUI, Zeineb; GOMAND, Julien; MALBURET, François; BARRE, Jean-Pierre
Fonte: ASME Publicador: ASME
EN
Relevância na Pesquisa
46.08%
In this paper, a complex multiphysics system is modeled using two different energy-based graphical techniques: Bond Graph and Energetic Macroscopic Representation. These formalisms can be used together to analyze, model and control a system. The BG is used to support physical, lumped-parameter modeling and analysis processes, and then EMR is used to facilitate definition of a control structure through inversion-based methodology. This complementarity between both of these tools is set out through a helicopter flight control subsystem.

Design methodology of a complex CKC mechanical joint with a representation energetic tool multi-Bond graph: application to the helicopter

BOUDON, Benjamin; MALBURET, François; CARMONA, Jean-Claude
Fonte: Springer Publicador: Springer
EN
Relevância na Pesquisa
66.28%
Due to the operation of the rotor, the helicopter is subject to important vibration levels affecting namely the fatigue of the mechanical parts and the passenger comfort. Suspensions between the main gear box (MGB) and the fuselage help to filter theses problematic vibrations. Their design can be difficult since the filtering should be efficient for different types of external forces (pumping force and roll/pitch torque) which may appear during the flight. As passive solutions classically show their limits, intelligent active solutions are proposed so that the filtering can be adjusted according to the vibration sources. Such studies still suffer from a lack of tools and methods, firstly, necessary to the design of complex mechanical systems (due to their multi-phase multi-physics multi-interaction characteristic, ...) and secondly, to develop of an intelligent joint. The main objective of this chapter is to provide a methodology for designing and analyzing an intelligent joint using an energetic representation approach: the multibond graph (MBG). This method is applied here to a complex mechanical system with closed kinematic chains (CKC) which is the joint between the main gear box (MGB) and the aircraft structure of a helicopter. Firstly...

An upper limb musculoskeletal model using bond graphs for rotorcraft-pilot couplings analysis

TOD, Georges; MALBURET, François; GOMAND, Julien; BARRE, Pierre-Jean
Fonte: SIMBIO-M Publicador: SIMBIO-M
EN
Relevância na Pesquisa
46.05%
Under certain flight conditions, a rotorcraft fuselage motions and vibrations might interact with its pilot voluntary and involuntary actions leading to potentially dangerous dynamic instabilities known as rotorcraft-pilot couplings (RPCs). A better understanding of this phenomenon could be achieved by being able to reproduce the phenomenon during simulations. Design guidelines could be then obtained at an early stage of development of rotorcrafts improving flight safety for pilots and passengers. In this work, an upper limb musculoskeletal model using bond graphs is presented. It is then integrated in a larger aeroelastic rotorcraft bond graph model that allows simulating pilot-rotor-fuselage couplings under several flight conditions. Simulations are performed and compared to literature’s models and experimental data.; “Complex Mechanical Systems Dynamics” project - Airbus Group Foundation - Arts et Metiers Paristech

Directed factor graph based fault diagnosis model construction for mode switching satellite power system

Zhang, Xiaolei; Shen, Yi; Wang, Zhenhua
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 21/12/2010
Relevância na Pesquisa
36.24%
Satellite power system is a complex, highly interconnected hybrid system that exhibit nonlinear and mode switching behaviors. Directed factor graph is an inference model for fault diagnosis using probabilistic reasoning techniques. A novel approach for constructing the directed factor graph structure based on hybrid bond graph model is proposed. The system components status and their fault symptoms are treated as hypothesis and evidences respectively. The cause-effect relations between hypothesis and evidences are identified and concluded though qualitative equations and causal path analysis on hybrid bond graph model. A power supply module of a satellite power system is provided as case study to show the feasibility and validity of the proposed method.

Modeling Switched Behavior with Hybrid Bond Graph: Application to a Tank system

Triki, Slim; Mekki, Taher; Kamoun, Anas
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 12/02/2014
Relevância na Pesquisa
46.28%
Different approaches have been used in the development of system models. In addition, modeling and simulation approaches are essential for design, analysis, control, and diagnosis of complex systems. This work presents a Simulink model for systems with mixed continuous and discrete behaviors. The model simulated was developed using the bond graph methodology and we model hybrid systems using hybrid bond graphs (HBGs), that incorporates local switching functions that enable the reconfiguration of energy flow paths. This approach has been implemented as a software tool called the MOdeling and Transformation of HBGs for Simulation (MOTHS) tool suite which incorporates a model translator that create Simulink models. Simulation model of a three-tank system that includes a switching component was developed using the bond graph methodology, and MoTHS software were used to build a Simulink model of the dynamic behavior.

Energy-based Analysis of Biochemical Cycles using Bond Graphs

Gawthrop, Peter J.; Crampin, Edmund J.
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Relevância na Pesquisa
36.28%
Thermodynamic aspects of chemical reactions have a long history in the Physical Chemistry literature. In particular, biochemical cycles - the building-blocks of biochemical systems - require a source of energy to function. However, although fundamental, the role of chemical potential and Gibb's free energy in the analysis of biochemical systems is often overlooked leading to models which are physically impossible. The bond graph approach was developed for modelling engineering systems where energy generation, storage and transmission are fundamental. The method focuses on how power flows between components and how energy is stored, transmitted or dissipated within components. Based on early ideas of network thermodynamics, we have applied this approach to biochemical systems to generate models which automatically obey the laws of thermodynamics. We illustrate the method with examples of biochemical cycles. We have found that thermodynamically compliant models of simple biochemical cycles can easily be developed using this approach. In particular, both stoichiometric information and simulation models can be developed directly from the bond graph. Furthermore, model reduction and approximation while retaining structural and thermodynamic properties is facilitated. Because the bond graph approach is also modular and scaleable...

Diagnosis of Switching Systems using Hybrid Bond Graph

Mekki, Taher; Triki, Slim; Kamoun, Anas
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 06/12/2013
Relevância na Pesquisa
46.41%
Hybrid Bond Graph (HBG) is a Bond Graph-based modelling approach which provides an effective tool not only for dynamic modeling but also for fault detection and isolation (FDI) of switching systems. Bond graph (BG) has been proven useful for FDI for continuous systems. In addition, BG provides the causal relations between systems variables which allow FDI algorithms to be developed systematically from the graph. There are many methods that exploit structural relations and functional redundancy in the system model to find efficient solutions for the residual generation and residual evaluation steps in FDI of switching systems. This paper describes two different techniques, quantitative and qualitative, based on common modelling approach that employs HBG. In quantitative approach, global analytical redundancy relationships (GARRs) are derived from the HBG model with a specified causality assignment procedure. GARRs describe the system behaviour at all of its operating modes. In qualitative approach, functional redundancy can be captured by a Temporal Causal Graph (TCG), a directed graph that may include temporal information; Comment: 8 pages

Modular Bond-graph Modelling and Analysis of Biomolecular Systems

Gawthrop, Peter; Crampin, Edmund
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 19/11/2015
Relevância na Pesquisa
46.37%
Bond graphs can be used to build thermodynamically-compliant hierarchical models of biomolec- ular systems. As bond graphs have been widely used to model, analyse and synthesise engineering systems, this paper suggests that they can play the same role in the modelling, analysis and syn- thesis of biomolecular systems. The particular structure of bond graphs arising from biomolecular systems is established and used to elucidate the relation between thermodynamically closed and open systems. Block diagram representations of the dynamics implied by these bond graphs are used to reveal implicit feedback structures and are linearised to allow the application of control- theoretical methods. Two concepts of modularity are examined: computational modularity where physical correct- ness is retained and behavioural modularity where module behaviour (such as ultrasensitivity) is retained. As well as providing computational modularity, bond graphs provide a natural formula- tion of behavioural modularity and reveal the sources of retroactivity. A bond graph approach to reducing retroactivity, and thus inter-module interaction, is shown to require a power supply such as that provided by the AT P = ADP + P i reaction. The MAPK cascade (Raf-MEK-ERK pathway) is used as an illustrative example which demon- strates how the computational modularity provided by the bond graph approach avoids the errors associated with assuming irreversible Michaelis-Menten kinetics and emphasises the necessity for a power supply to support behavioural modularity in signalling networks.

Hierarchical Bond Graph Modelling of Biochemical Networks

Gawthrop, Peter J.; Cursons, Joseph; Crampin, Edmund J.
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Relevância na Pesquisa
46.33%
The bond graph approach to modelling biochemical networks is extended to allow hierarchical construction of complex models from simpler components. This is made possible by representing the simpler components as thermodynamically open systems exchanging mass and energy via ports. A key feature of this approach is that the resultant models are robustly thermodynamically compliant: the thermodynamic compliance is not dependent on precise numerical values of parameters. Moreover, the models are reusable due to the well-defined interface provided by the energy ports. To extract bond graph model parameters from parameters found in the literature, general and compact formulae are developed to relate free-energy constants and equilibrium constants. The existence and uniqueness of solutions is considered in terms of fundamental properties of stoichiometric matrices. The approach is illustrated by building a hierarchical bond graph model of glycogenolysis in skeletal muscle.; Comment: 35 pages, 12 figures

Evaluation of bond graph based object oriented approach to determination of natural frequencies of packaging system elements

Jaram, Vladimir
Fonte: Rochester Instituto de Tecnologia Publicador: Rochester Instituto de Tecnologia
Tipo: Tese de Doutorado
EN_US
Relevância na Pesquisa
46.39%
Packaged items passing through distribution system encounter vibrations. It needs to be examined what happens to an object, packaged or unpackaged, in the distribution environment when it is subject to outside vibrations, so that we may predict its behavior resulting from distribution vibrations. To prevent product loss from both static and dynamic forces encountered in distribution, corporations are turning in increasing numbers to services of package engineering. This work evaluates the application of Bond Graphs Based Object-Oriented Approach to Determination of Natural Frequencies of Packaging System Elements. Using the Bond Graph, a model of the Package-product system under testing was developed to closely simulate the real testing model and conditions. The testing model equipment and packaging system were developed using the Bond Graph computer assisted modeling approach. Using simulation, vibrations characteristics of the packaging model were obtained, i.e., natural frequencies and other relevant properties of the system (model). An analysis of the frequency characteristics was conducted by application of physical modeling using a suitable visual computer development platform. The results obtained by simulation, and those obtained on the vibration table (32...