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Dimensionnement d’un actionneur pour organe de pilotage à entraînement direct avec redondance passive magnétique / Design of an active flight control direct drive actuator with a passive magnetic redundancyAllias, Jean-François 30 November 2015 (has links)
Ce manuscrit de thèse, intitulé " Dimensionnement d’un actionneur pour organe de pilotage à entraînement direct avec redondance passive magnétique ", s’inscrit dans un projet ANR du nom de TEMOP pour, TEchnologie Mécatronique pour Organe de Pilotage, en lien avec la société UTC Aerospace de Figeac. L’objectif de cette thèse est de développer une solution de machine électrique permettant de générer le retour d’effort actif d’un mini-manche latéral d’aéronef, dans le but d’améliorer les sensations haptiques des pilotes. Cette machine doit être assez performantes pour générer des efforts massiques importants, tout en tenant dans un encombrement réduit et en limitant l’échauffement. Un cahier des charges précis rédigé par l’industriel donne les contraintes à respecter et impose une redondance triplex sur chaque axe de tangage et de roulis. Nous avons opté pour une solution comportant un duplex actif associé à un simplex passif. Sur chaque axe, deux machines électriques actives seront montées en parallèle et une solution à retour d’effort passif magnétique a été développée. Pour ce faire, nous avons divisé notre thèse en deux parties distinctes. La première partie du manuscrit traite du dimensionnement de la machine active appelée DARM pour Double Airgap Rotative Machine. Il s’agit d’une machine synchrone à aimants permanents en configuration Halbach, comportant deux entrefers et à débattement limité. La stratégie de dimensionnement est basée sur une optimisation locale et analytique sous contraintes non-linéaires. La première partie développe les contraintes sous forme analytiques. Puis, un modèle magnétique est créé de manière à connaître le couple que la structure développe en fonction des différentes variables d’optimisation. Ce modèle a été validé par éléments finis grâce aux logiciels ANSYS et JMAG. Une optimisation permet d’aboutir aux dimensions de l’actionneur satisfaisant au cahier des charges. Puis, dans le but de vérifier les températures atteintes dans chaque zones, un modèle thermique global, utilisant des résistances thermiques équivalentes a été établi et validé par simulations. Ainsi, on vérifie que la structure optimisée n’atteint pas des températures critiques. Enfin, nous validerons nos calculs par des mesures expérimentales. Un chapitre du manuscrit est dédié au dimensionnement de la partie passive. Nous avons imaginé un système innovant qui couple une fonction de ressort et d’amortisseur. La fonction de ressort s’appuie sur le phénomène de répulsion entre deux aimants permanents, alors que la fonction d’amortisseur est créée par un système de freinage passif par courants de Foucault. La stratégie de dimensionnement est divisée en deux partie. Les dimensions du système de ressort sont préalablement choisies grâce à une optimisation paramétrique locale couplant le logiciel MATLAB au logiciel de simulations par éléments finis FEMM. Lorsque ces dimensions sont fixées, le système d’amortisseur est dimensionné par une optimisation locale analytique où la fonction objectif a pour vocation de maximiser le couple de freinage. Nous nous sommes donc entachés à développer un modèle qui permet de calculer ce couple. Sur cette base, un prototype a été élaboré, sur lequel des mesures expérimentales ont permis de valider le concept. / This thesis manuscript titles "Dimensionnement d’un actionneur pour organe de pilotage à entraînement direct avec redondance passive magnétique ", which means " Design of an active flight control direct drive actuator with a passive magnetic redundancy ", is seen against an ANR project named TEMOP for, " TEchnologie Mécatronique pour Organe de Pilotage ", and is in connection with the UTC Aerospace industry in Figeac in France. The objective of this thesis is to develop a solution of electrical machine, which permits to create an active force feed-back for an aircraft side-stick, in order to improve the haptic sensations of the pilot. This machine have to be enough powerful to create high forces per unit of mass. We also need to respect the overall dimensions and to decrease the heating as much as possible. A precise set of specifications, redacted by UTC Aerospace, gives the constraints and impose to have a triple redundancy on each axis of pitch and roll. We chose to develop a duplex active redundancy with an added simplex passive actuator. Our full system have 6 machines : 4 are actives and 2 are passives. Our thesis is divided in two main parts. The first part of the manuscript deals with the design of the active machine called DARM for " Double Airgap Rotative Machine ". It is a synchronous permanent magnet machine, with a Halbach pattern, with two airgaps and a non-entire arc. The design method is based on an analytical optimization process under a set of non-linear constraints. Each of them are traduced mathematically and an electromagnetic 2D model is developed, in order to give the theoretical torque reached, in function of the variables of the problem. This model has been validated with FEM simulations with the ANSYS and JMAG softwares. An optimization is realized to give the dimensions of the DARM. Then, in order to verify the temperatures, we developed a global thermal model, based on an equivalent electric circuit. It permits to verify that the temperatures reached in the structure, are under the limits given by the set of specifications. This model is verified by FEM simulations using ANSYS. Finally, we will validate our models with experimental measures. However, a chapter is dedicated to the design of the passive actuator. We imagined an innovative system, which have two different utilities. The first one is a function of spring, the second is a function of shock absorber. The spring is based on the repulsion phenomenon between two magnets. The shock absorber is created with a system of Eddy currents breaker. The design method is divided in two. In the first time, we design the spring with a parametric optimization using the FEMM software coupled to the MATLAB software. When the dimensions of the spring are known, we design the shock absorber with an analytical optimization process which use an electromagnetic torque model developed in this part. A prototype has been built in order to verify the models.
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Vergleich der Verluste in permanentmagneterregten Synchronmaschinen gespeist durch 3-Level-TNPC- oder 2-Level-StromrichterSchlegel, Ludwig, Knapp, Tobias, Hofmann, Wilfried 21 September 2021 (has links)
Dieser Beitrag untersucht die Verluste elektrischer Maschinen in Abhängigkeit von der verwendeten Stromrichtertopologie und bei verschiedenen Pulsfrequenz. Beispielhaft wird eine permanentmagneterregte Synchronmaschine (PMSM) mit einer Bemessungsleistung von 18 kW behandelt. Zum Betrieb der Maschine wird der Prototyp des 3-Level-Stromrichters LT300-ML
von M&P Motion Control and Power Electronics GmbH (M&P) verwendet. Beim 3-Level-Stromrichter werden mehr Spannungsebenen geschaltet als beim 2-Level-Stromrichter. Dies
führt zu einer geringeren Stromwelligkeit und u. a. zu geringeren Verlusten in der Maschine. Die Messergebnisse zeigen, dass die Maschinenverluste im Vergleich zum Einsatz eines
2-Level-Stromrichters um 20 ... 30 % reduziert werden können. Für die Untersuchung wird der M&P-Maschinen-Prüfstand verwendet. / This paper deals with the losses of electrical machines depending on the converter topology used and with different switching frequency’s. A permanent magnet synchronous machine (PMSM)
with a rated output power of 18 kW is investigated. As power converter the LT300-ML (3-level converter) from M&P Motion Control and Power Electronics GmbH (M&P) is used. By using a 3-level topology, more voltage levels are switched than with a 2-level topology. This, among other things, results in a lower current ripple and lower losses in the machine. The measurement results show that the machine losses can be reduced by 20 ... 30 % compared to the use of a 2-level converter. The M&P machine test bench is used for the investigation.
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Algoritmy prediktivního řízení elektrických pohonů / Electrical Drives Predictive Control AlgorithmsMynář, Zbyněk January 2014 (has links)
This work deals with the predictive control algorithms of the AC drives. The introductory section contains summary of current state of theory and further description and classification of most significant predictive algorithms. A separate chapter is dedicated to linear model predictive control (linear MPC). The main contribution of this work is the introduction of two new predictive control algorithm for PMSM motor, both of which are based on linear MPC. The first of these algorithms has been created with the aim of minimizing its computational demands, while the second algorithm introduces the ability of field weakening. Both new algorithms and linear MPC were simulated in MATLAB-Simulink.
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Modélisation non-linéaire des machines synchrones pour l'analyse en régimes transitoires et les études de stabilité / Nonlinear modelling of synchronous machines for transient analyses and stability studiesWisniewski, Teodor 12 December 2018 (has links)
Les travaux de recherche présentésdans cette thèse ont été effectués dans le cadred'une collaboration entre Leroy Somer et lelaboratoire de génie électrique et électronique deParis (GeePs). Ils ont pour objectif lessimulations des phénomènes observés en modetransitoire des machines électriques. Cessimulations sont particulièrement orientées parles nouvelles exigences issues du Grid Code pourles alternateurs connectés au réseau.Principalement, deux types de modèles ont étédéveloppés. Le premier se base sur unereprésentation de l’état magnétique de lamachine où chaque flux est exprimé en fonctiondes courants des différentes bobines. Le secondmodèle regroupe les courants en utilisant descourants magnétisants sur les axes d et q associésà des coefficients de saturation pour chaque fluxet simplifie la représentation magnétique,notamment pour la prise encompte du circuit amortisseur. Avec unemodélisation suffisamment précise ducomportement magnétique non linéaire de lamachine, ils permettent de mieux prédire lescourants et le couple électromagnétique lors desdéfauts tels que les creux de tension. Les travauxeffectués présentés dans ce mémoire ont permis,en partant des descriptions des saturationstrouvées dans une machine, de définir desméthodes pour incorporer la saturation dans lesmodèles de type circuit et finalement d’aboutirau choix du modèle non-linéaire pour unemachine électrique donnée. Grâce à un temps decalcul réduit, ils ont aussi conduit à l'intégrationsous Simulink de modèles de la machine et dusystème d'entrainement pour la réalisationd'études de stabilité et pour créer unenvironnement de mise au point de la commandedu système. / The research presented in this thesiswas carried out in the research and developmentproject between Leroy Somer and the Group ofElectrical Engineering of Paris (GeePs). Theirobjective is to simulate the phenomena observedin the transient states of electrical machines.These simulations are particularly oriented bythe new Grid Code requirements for alternatorsconnected to the power network. Two types ofmodels have been principally developed. Thefirst one is based on a magnetic description ofthe machine where each flux is expressed as afunction of the currents flowing through thedifferent machine windings. The second oneregroups the different winding currents by usingthe magnetizing currents on axes d and qassociated to saturation coefficients for eachflux linkage and simplifies the magneticdescription, especially when taking into accountthe damper windings. With a sufficiently precisemodelling of the non-linear magnetic behaviourof the machine, it is possible to better predict thecurrents and the electromagnetic torque underfault conditions such as voltage drops. The workcarried out in this thesis has made possible,starting from the descriptions of the saturationeffects found in a machine, to define methodsfor incorporating saturation into circuit models.Finally, one can make a choice of the dynamicnon-linear model for a given machine. Thanks toshort computation time, it also led to theSimulink integration of the machine andexcitation system models paving the way forstability and control studies.
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Identification of synchronous machine stability parameters using a quasilinearization-least-square-error algorithmBourawi, Mustafa S. January 1984 (has links)
No description available.
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Output Impedance Modeling and Measurement of a 28 kW Synchronous GeneratorShan, Keyue 09 June 2022 (has links)
Synchronous machines (SMs) are a vital part of today's world, and precise modeling is important for studying their stability. In this thesis, a small-signal analysis is done on the d-q frame for the AC SM. Starting from formulating the SM's abc frame equations, a d-q transformation is done based on the SM rotor frame so that the inductance from the abc frame representation will be fixed. Then, the SM's fundamental parameters are obtained from standstill frequency response testing. In the interest of having the most complete model possible, a governor controller and an exciter controller have been designed, and their performance has been evaluated according to the International Standard ISO-8628. A d-q steady-state analysis has been carried out and the resulting small-signal perturbation has been added to the steady-state equations. The model has been analyzed with exciter control only, with governor control only, and with both controllers, and in the end, the small-signal d-q impedance model for the SM has been verified by simulations and experiments in the Center for Electronics Systems (CPES) at Virginia Tech. The impedance measurement unit (IMU) was built by CPES. It is designed for measuring three-phase AC power systems and DC systems. Nevertheless, even though the single-phase system can be connected to the IMU, the impedance result in the end is not correct. Modifications have been made to the IMU so that it is able to calculate the single-phase AC power system impedance. The experimental results demonstrate that implementation has been completed. / Master of Science / Emergency diesel generators are critical in the event of widespread blackouts. Generators are typically synchronous machines (SMs), and stability studies are crucial from the standpoint of the power system. With knowledge gained through stability analysis, if instability occurs, a solution can be quickly formulated based on phenomena that has been observed during the event. In order to study the system stability, an accurate model is essential. The small-signal d-q impedance model will be derived by the Center for Power Electronics Systems (CPES) at Virginia Tech based on an AC generator that is rated at 28 kW, and the impedance results will be verified by both MATLAB/Simulink simulations and experiments. The impedance measurement unit (IMU) will serve as the equipment to do the measurement. However, the IMU can only correctly calculate impedance for a three-phase power system. For the single-phase AC power system, due to the three-phase phase locker loop (PLL) calculating the wrong angle, the IMU cannot properly determine the impedance. However, modifications have been applied to the IMU so that it can automatically calculate the impedance for a single-phase AC power system.
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Design and Evaluation of a Photovoltaic Inverter with Grid-Tracking and Grid-Forming ControlsRye, Rebecca Pilar 20 March 2020 (has links)
This thesis applies the concept of a virtual-synchronous-machine- (VSM-) based control to a conventional 250-kW utility-scale photovoltaic (PV) inverter. VSM is a recently-developed control scheme which offers an alternative grid-synchronization method to the conventional grid-tracking control scheme, which is based on the dq phase-locked-loop- (PLL-) oriented vector control. Synchronous machines inherently synchronize to the grid and largely partake in the stabilization of the grid frequency during power system dynamics. The purpose of this thesis is primarily to present the design of a grid-forming control scheme based on the VSM and the derivation of the terminal dq-frame ac impedance of the small-signal model of the inverter and control scheme. This design is also compared to the design of the conventional grid-tracking control structure, both from a loop design and terminal dq-frame ac impedance standpoint. Due to the inherent lax power-balance synchronization, the grid-forming control scheme results in 1 to 2 decades' lower frequency range of negative incremental input impedance in the diagonal elements, which is a favorable condition for stability. Additionally, the stability of the grid-forming control scheme is compared to the conventional grid-tracking control using the generalized Nyquist criterion (GNC) for stability under three modes of operation of active and reactive power injection. It is found that the connection is stable for both control schemes under unity power factor and fixed reactive power modes; however, the grid-forming control is able to inject twice the amount of active power under the voltage regulation mode when compared to the grid-tracking control. / Master of Science / Concerns about the current and future state of the environment has prompted government and non-profit agencies to enact regulatory legislation on fossil fuel emissions. In 2017, electricity generation comprised 28% of total U.S. greenhouse gas emissions with 68% of this generation being due to coal combustion sources. As a result, utilities have retired a number of coal power plants and have employed alternative means of power generation, specifically renewable energy sources (RES).
Most RES operate as variable-frequency ac sources (wind) or dc sources (solar) and are interfaced with the power grid through ac-dc-ac or dc-ac converters, respectively, which are power-electronic devices used to control the injection of power to the grid. Conventional converters synchronize with the grid by tracking the phase of the voltage at the point of common coupling (PCC) through a phase-locked loop (PLL). While power system dynamics significantly affect the performance of a PLL, and, subsequently, inverters' operation, the initial frequency regulation during grid events is attributed to the system's inherent inertia due to the multitude of synchronous machines (SM). However, with the steady increase of RES penetration, even while retaining the number of SM units, the net inertia in the system will decrease, thus resulting in prolonged responses in frequency regulation to the aforementioned dynamics.
This thesis investigates the control of variable-frequency sources as conventional synchronous machines and provides a detailed design procedure of this control structure for photovoltaic (PV) inverter applications. Additionally, the stability of the connection of the inverter to the grid is analyzed using innovative stability analysis techniques which treat the inverter and control as a black box. In this manner, the inner-workings of the inverter need not be known, especially since it is proprietary information of the manufacturer, and the operator can measure the output response of the device to some input signal.
In this work, it is found that the connection between the inverter and grid is stable with this new control scheme and comparable to conventional control structures. Additionally, the control based on synchronous machine characteristics shows improved stability for voltage and frequency regulation, which is key to maintaining a stable grid.
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Synchronized Rotor Angle Measurement of Synchronous MachinesMazur, David Christopher 31 May 2012 (has links)
A key input parameter to governor feedback control and stability protection of generators is the angle of the induced voltage internal to the generator. Current practice is to estimate this value using measurements from the terminals of the generator and mathematical models. This project aims to develop a system that would directly measure the internal angle of the generator using a rotary encoder on the shaft of the machine. This document describes the theory and experimental setup of this proposed system and outlines the test procedure of experimentation. / Master of Science
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Quantification of uncertainty in the magnetic characteristic of steel and permanent magnets and their effect on the performance of permanent magnet synchronous machineAbhijit Sahu (5930828) 15 August 2019 (has links)
<div>The numerical calculation of the electromagnetic fields within electric machines is sensitive to the magnetic characteristic of steel. However, the magnetic characteristic of steel is uncertain due to fluctuations in alloy composition, possible contamination, and other manufacturing process variations including punching. Previous attempts to quantify magnetic uncertainty due to punching are based on parametric analytical models of <i>B-H</i> curves, where the uncertainty is reflected by model parameters. In this work, we set forth a data-driven approach for quantifying the uncertainty due to punching in <i>B-H</i> curves. In addition to the magnetic characteristics of steel lamination, the remanent flux density (<i>B<sub>r</sub></i>) exhibited by the permanent magnets in a permanent magnet synchronous machine (PMSM) is also uncertain due to unpredictable variations in the manufacturing process. Previous studies consider the impact of uncertainties in <i>B-H</i> curves and <i>B<sub>r</sub></i> of the permanent magnets on the average torque, cogging torque, torque ripple and losses of a PMSM. However, studies pertaining to the impact of these uncertainties on the combined machine/drive system of a PMSM is scarce in the literature. Hence, the objective of this work is to study the effect of <i>B-H</i> and <i>B<sub>r</sub></i> uncertainties on the performance of a PMSM machine/drive system using a validated finite element simulator. </div><div>Our approach is as follows. First, we use principal component analysis to build a reduced-order stochastic model of <i>B-H</i> curves from a synthetic dataset containing <i>B-H</i> curves affected by punching. Second, we model the the uncertainty in <i>B<sub>r</sub></i> and other uncertainties in <i>B-H</i> characteristics e.g., due to unknown state of the material composition and unavailability of accurate data in deep saturation region. Third, to overcome the computational limitations of the finite element simulator, we replace it with surrogate models based on Gaussian process regression. Fourth, we perform propagation studies to assess the effect of <i>B-H</i> and <i>B<sub>r</sub></i> uncertainties on the average torque, torque ripple and the PMSM machine/drive system using the constructed surrogate models.</div>
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Cálculo da força contra eletromotriz em máquinas síncronas com ímãs na superfície do rotor / Assessment of surface mounted magnet synchronous machine\'s on-load back-EMFPaula, Geyverson Teixeira de 28 April 2016 (has links)
O presente trabalho trata do cálculo da força contra eletromotriz em carga de uma máquina síncrona com ímãs na superfície do rotor (cuja forma de onda de força contra eletromotriz é não senoidal) sendo esta alimentada por correntes de fase cujas forma de onda são quadradas. Para conduzir esta investigação e calcular a força contra eletromotriz da máquina em estudo, faz-se uma revisão sobre o Método da Permeabilidade Fixa, método este que permite a linearização do ponto de operação da máquina. Dessa forma, as simulações são conduzidas por meio do método dos elementos finitos e do Método da Permeabilidade Fixa, levando-se em conta a forma de onda da corrente de alimentação. Atenção especial é dada ao modo que se analisa o fluxo concatenado e a forma de obtenção da força contra eletromotriz uma vez que as formas de onda do fluxo concatenado sofrem variações abruptas a cada 60º elétricos. Além destes parâmetros, analisa-se também cada uma das parcelas do torque eletromagnético, i.e., torque mútuo, torque de relutância e torque de borda, sendo realizado ao final do trabalho, uma comparação entre a soma da estimativa de cada parâmetro com o valor do torque eletromagnético obtido por meio de uma simulação não linear. / This work deals with the assessment of a surface mounted magnet synchronous machine\'s parameters (whose back-EMF is approximately trapezoidal) and that is fed by an ideal square current waveform. In order to investigate and describe each machine\'s parameter, a review on Frozen Permeability Method is presented. Some simulation by means of finite element method with the aid of Frozen Permeability Method are carried out taking into account that the machine is fed by an ideal square current waveform. The results for flux-linkage wave-form and back-EMF waveform are shown and analyzed. A special attention is given to back-EMF calculation since the linkage flux of each phase has an abrupt change every sixty electrical degrees due to the phase commutation. In addition, an attention is given to each torque component on load condition, i.e., mutual torque, reluctance torque, cogging torque and a comparison between the electromagnetic torque and the summation of these components.
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