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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.
41

Modelagem eletromagnética e mecânica de máquinas síncronas para estudo de vibrações no núcleo do estator. / Electromagnetic and mechanical modelling of synchronous machines for study of stator core vibration.

Barros, Allan de 25 June 2019 (has links)
O campo magnético estabelecido no entreferro das máquinas síncronas é responsável pela transmissão do torque e potência desejados, porém é também precursor de forças radiais inerentes. Tais forças combinadas à resposta dinâmica do sistema mecânico podem resultar em vibração excessiva do núcleo do estator, o que em geral é indesejável devido a eventuais danos e redução de vida útil decorrentes. Este trabalho tem como objetivo principal desenvolver modelos e simulações focados nas forças eletromagnéticas atuantes no núcleo do estator de tal forma que estes possam contribuir para compreensão global dos fenômenos envolvidos bem como para refinamento de resultados já conhecidos. De forma complementar, modelos mecânicos analíticos do núcleo do estator existentes na literatura serão explorados com a finalidade de, em conjunto com as forças eletromagnéticas encontradas, se obter o comportamento vibracional global da estrutura do núcleo do estator. Validação experimental dos resultados também é discutida com base em ensaios em duas máquinas reais. / The magnetic field established in the airgap of a synchronous machine is responsible for the desired torque and power transmission; however it is also precursor of inherent radial forces. Such forces combined to the dynamic response of the mechanical system can result in excessive stator core vibration, what is in general undesirable due to eventual damages and life span reduction. This work has the main objective of developing models and simulations focused on the electromagnetic forces acting on the stator core in such a way that they can contribute for the global comprehension of involved phenomena as well as for the refinement of already known results. Complementarily, analytical mechanical models of the stator core available in the literature will be explored with the goal of, in conjunction with the obtained electromagnetic forces, deriving the global vibrational behavior of the stator core structure. Experimental validation of results is also discussed based on tests performed in two real machines.
42

On impacts and ride-through of voltage sags exposing line-operated AC-machines and metal processes

Carlsson, Fredrik January 2003 (has links)
During the last decade, power quality has been recognised asa global problem. Among different types of power qualityproblems, voltage sags have been identified to be one of themost severe problems for different process industries. The mostcommon reason to voltage sags is lightning strikes in powerlines. Protection equipment, usually located at switchyards,disconnect faulted power lines as soon as possible, which isapproximately 100 ms. Thus, the duration of voltage sags areapproximately 100 ms. The sensitivity to voltage sags ofelectrical equipment in process industries can be observed asfor instance malfunction, automatic turnoff or damages. This thesis gives an overview of three metals processes withfocus on the sensitivity to voltage sags and interruptions. Theinherent energy in the process is used to find the sensitivity.This energy may also be used to obtain "ride-through" for theprocesses. The three metals processes are a blast furnaceprocess, a hot rolling mill process and a cold rolling millprocess. The main attention in this thesis is paid to the blastfurnace process, which is powered by a line-operatedsynchronous machine. The thesis shows that the protection equipment forelectrical machines can be adjusted to avoid unnecessaryshutdowns. It is also explained why there are high torque andcurrents during voltage sags as well as after voltage sags. Itis shown that the first peak torque and current during thevoltage sags is almost proportional to the voltage change, thatis the voltage magnitude before the voltage sag minus thevoltage magnitude during the voltage sag. The first peak torqueand current after the voltage sag depends sinusoidal-like onthe duration of the voltage sag and almost proportional to thevoltage change during the voltage sag. There is no fluxsaturation during voltage sags, however after voltage sagssaturation is very likely to occur. The thesis explains why andalso how the flux is changed during and after voltage sags. The duration of voltage sags is in many cases set by theprotection equipment located in switchyards. It is shown thatthe durations of voltage sags can be changed to durations thatwill cause less peak torque and current after voltage sags forline-operated AC-machines. It is also shown how this istheoretically achieved. <b>Keywords:</b>Rolling mill, Blast furnace, Power Quality,Synchronous machine, Asynchronous machine, Voltage sag, Voltageinterruption, Ride-through, Process disturbances, Simulation,Modelling
43

On impacts and ride-through of voltage sags exposing line-operated AC-machines and metal processes

Carlsson, Fredrik January 2003 (has links)
<p>During the last decade, power quality has been recognised asa global problem. Among different types of power qualityproblems, voltage sags have been identified to be one of themost severe problems for different process industries. The mostcommon reason to voltage sags is lightning strikes in powerlines. Protection equipment, usually located at switchyards,disconnect faulted power lines as soon as possible, which isapproximately 100 ms. Thus, the duration of voltage sags areapproximately 100 ms. The sensitivity to voltage sags ofelectrical equipment in process industries can be observed asfor instance malfunction, automatic turnoff or damages.</p><p>This thesis gives an overview of three metals processes withfocus on the sensitivity to voltage sags and interruptions. Theinherent energy in the process is used to find the sensitivity.This energy may also be used to obtain "ride-through" for theprocesses. The three metals processes are a blast furnaceprocess, a hot rolling mill process and a cold rolling millprocess. The main attention in this thesis is paid to the blastfurnace process, which is powered by a line-operatedsynchronous machine.</p><p>The thesis shows that the protection equipment forelectrical machines can be adjusted to avoid unnecessaryshutdowns. It is also explained why there are high torque andcurrents during voltage sags as well as after voltage sags. Itis shown that the first peak torque and current during thevoltage sags is almost proportional to the voltage change, thatis the voltage magnitude before the voltage sag minus thevoltage magnitude during the voltage sag. The first peak torqueand current after the voltage sag depends sinusoidal-like onthe duration of the voltage sag and almost proportional to thevoltage change during the voltage sag. There is no fluxsaturation during voltage sags, however after voltage sagssaturation is very likely to occur. The thesis explains why andalso how the flux is changed during and after voltage sags.</p><p>The duration of voltage sags is in many cases set by theprotection equipment located in switchyards. It is shown thatthe durations of voltage sags can be changed to durations thatwill cause less peak torque and current after voltage sags forline-operated AC-machines. It is also shown how this istheoretically achieved.</p><p><b>Keywords:</b>Rolling mill, Blast furnace, Power Quality,Synchronous machine, Asynchronous machine, Voltage sag, Voltageinterruption, Ride-through, Process disturbances, Simulation,Modelling</p>
44

MODELING AND VALIDATION OF A SYNCHRONOUS-MACHINE/CONTROLLED-RECTIFIER SYSTEM

Hord, Kyle A 01 January 2014 (has links)
The hardware validation of a novel average-value model (AVM) for the simulation of a synchronous-generator/controlled rectifier system is presented herein. The generator is characterized using genetic algorithm techniques to fit standstill frequency response (SSFR) measurements to q and d-axis equivalent circuits representing the generator in the rotor reference frame. The generator parameters form the basis of a detailed model of the system, from which algebraic functions defining the parametric AVM are derived. The average-value model is compared to the physical system for a variety of loading and operating conditions including step load change, change in delay angle, and external closed-loop control, validating the model accuracy for steady-state and transient operation.
45

Design of a reluctance synchronous machine for an electric vehicle with a multi speed gearbox

Vorster, Christiaan Willem 12 1900 (has links)
Thesis (MEng)--Stellenbosch University, 2014. / ENGLISH ABSTRACT: Conventional electrical vehicles (EVs) favour mostly permanent magnet machines with single speed gearboxes. This is understandable, the PM machine has a high power density making the electrical machine smaller in size. The PM machine also has a favourable field weakening capability combining this with a single speed gearbox nearly perfectly matches the required traction curve. However the dependency of rare earth metals from China and the environmental issues raised by mining these metals raise concern. Therefore alternatives should be considered. Induction -, switch reluctance - and wound rotor machines are all gaining ground as favourable traction machines to power vehicles. The reluctance synchronous machine (RSM) is known for it’s robustness and high efficiency, however the machine has a limited field-weakening capability. To overcome this short coming a multi gearbox from an internal combustion engine (ICE) is suggested. By combining the RSM and multi speed gearbox it is possible to match the traction curve. There are numerous advantages offered by using this system, especially from an performance and efficiency point of view. However there are also numerous challenges faced by using the suggested powertrain, however the focus of this study is mainly on performance and efficiency of the motor and the powertrain. As a case study a Corsa 140i is used and the design specifications is taken from the ICE. The aim is to design a RSM that meets the specifications of the ICE. The RSM structure is mathematically modelled then optimized using commercial optimization and 2D finite element software. To evaluate the design of the RSM, the motor is then tested. The powertrain is then tested by connecting the motor onto the gearbox of the Corsa and the efficiency of the powertrain is evaluated. The test results it shown that the RSM can be used as a traction motor. There are two motors built one with NO20 and the other with M530-65A lamination steel. Both motors perform well throughout the speed and torque spectrum. The measured efficiency at the rated condition for the motor with the NO20 steel is above 91% and the motor with the M530-65A laminations above 89%. The power train is is tested in 4th and 5th gear. The efficiency of 4th and 5th gear is approximated and the efficiency is above 90% . This high efficiency makes the multi speed gearbox a competitor for the EV power train. / AFRIKAANSE OPSOMMING: Elektrisie voertuie (EVe) het meestal permanent magneet motors met ’n enkel spoed ratkas. Dit is verstaanbaar, die PMS masjien het ’n hoë krag digtigheid wat die masjien kleiner maak in grote. Die PMS masjien het ’n baie goeie vloed veld verswakkings gebied en as dit gekombineer word met ’n enkel spoed ratkas, volg dit die velangde traksie kurwe amper perfek. Die nadeel is dat die PMS motor skaars aard metale nodig het vir die magnete van China af. Die probleem is dat daar baie omgewings probleme gepaard gaan om die metale te myn en China beheer die mark. As gevolg hiervan moet ander tipe motors oorweeg word as traksie motors vir voertuie. Skakel reluktansie, induksie en ’n wikkel rotor motors is almal besig om vordering te maak as traksie motors vir EV’e. Die sinchroon reluktansie motor (RSM) is bekend as ’n robuuste en effektiewe motor. Die probleem met die RSM is dat dit nie ’n goeie vloed veld verswakkings gebied het nie. Om die probleem te oorkom, word ’n veranderlike spoed ratkas van ’n binnebrand engin voorgestel. Deur om die RSM en die veranderlike spoed ratkas as ’n dryfstelsel te gebruik kan die verlangde traksie kurwe ook verkry word. Daar is talle voordele om ’n veranderlike spoed ratkas te gebruik, veral van af ’n draaimoment verrigting en effektiwiteits oogpunt. Daar is ongelukkig ook baie uitdagings wat gepaard gaan as ’n veranderlike spoed ratkas gebruik wil word in die dryfstelsel. Alhoewel daar baie uitdagings is kyk die studie slegs na die draaimoment verrigting en die effektiwiteit van die dryfstelsel. ’n Corsa 140i word as ’n gevallestudie gebruik en die spesifikasies vir die elektrisie motor word vanaf die spesifikasies van die binnebrand engin geneem. Die doel is om ’n motor te ontwerp wat dieselfde spesifikasies het as die binnebrand engin. Die RSM strukstuur word wiskundig gemodelleer en dan geoptimeer deur gebruik te maak van kommersiele optimering en 2D eindige element sagteware. Om die ontwerp te verifieer word die motor getoets. Die dryfstelsel word dan getoets deur om die motor met die raktas te konnekteer. Die draaimoment verrigting en die effektiwiteit word dan ge-evalueer. Twee motors word gebou, een met NO20 laminasies en een met M530-65A laminasies. Beide motors het goeie verrigting deur die spoed en draaimoment gebied. Die gemeete effektiwiteit van die motor met die NO20 laminasies is bo 91% en die motor met die M530-65A laminasies het ’n gemeete effektiwiteit bo 89%. Die toets resultate wys dat die RSM as ’n traksie motor gebruik kan word. Die dryfstelsel word in 4de en 5de rat ge-evalueer. Die effektiwiteit van die ratkas in 4de en 5de word benader en ’n effektiwiteit bo 90% is verkry. Hierdie hoë effektiwiteit maak die veranderlike spoed ratkas ’n lewensvatbare mededinger in die EV dryfstelsel.
46

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-EMF

Geyverson Teixeira de Paula 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.
47

Modeling and Design of the Electric Drivetrain for the 2013 Research Concept Vehicle

Camacho Silva, Leandro January 2013 (has links)
The research for electric vehicles has been growing during last years and the development of electric drive trains can be considered a main challenge. This thesis presents the electric drive train of the research concept vehicle (RCV) 2013, with particular focus on electric machines, motor controllers, and the communication system. In the first part of this thesis, the electric drive train configuration and components are described. In-wheel motors are proposed which is a permanent magnet synchronous machine (PMSM). This technology allows the use of autonomous corner modules (ACM) increasing the quality and safety of the system. Each of the four in-wheel motors has a controller enabling the use of torque or speed control mode. Furthermore, a dSPACE unit provides the total control of the system by CAN bus. Additionally, the dSPACE ControlDesk interface used to control the drive system is presented. In the second part, the heat sink of the AC Drive is investigated by measurements and analytical calculations. Furthermore, the motor temperature at different loads is also presented and discussed. Finally, the efficiency of an in-wheel motor (PRA 230) is studied. Also the efficiency of the motor controller is estimated and discussed.
48

Identifizierung elektromagnetischer und elektromechanischer Parameter von Schenkelpolmaschinen durch gekoppelte Genetische Algorithmen

Halank, Alexej 25 April 2022 (has links)
Die exakte Parametrierung von Schenkelpolmaschinen zur realitätsgetreuen Nachbildung in dynamischen Simulationsmodellen stellt in der Praxis eine große Herausforderung dar. Neben fundierten Kenntnissen über die durchzuführenden Messungen ist auch eine sachgemäße Interpretation der Messergebnisse erforderlich. Gerade bei Spezialmaschinen wie Einphasensynchrongeneratoren oder bei einem größeren Maschinenpark, welcher parametriert werden soll, kann der Aufwand unüberschaubar werden. Der gesamte Prozess ist insgesamt zeit- und kostenintensiv sowie fehleranfällig. Die vorliegende Arbeit behandelt die generische und rechnergestützte Parameterbeschaffung von Schenkelpolsynchronmaschinen als Unterstützung der bisherigen Parametrierungsmethoden sowohl für 50-Hz-Drehstrommaschinen als auch für Spezialanwendungen wie Bahnstromgeneratoren oder Bahnumformer mit Sonderfrequenz 16,7 Hz. Für die Untersuchung von Dreiphasensynchronmaschinen hinsichtlich dynamischer Vorgänge in Simulationen kommen die Modellansätze in der absoluten und in der bezogenen Parameterebene zur Anwendung. Bei der Umrechnung dieser beiden Ebenen ineinander müssen die Stromverläufe für die gleiche Wicklungen identisch sein. Dies ist in der Praxis durch die häufige Vernachlässigung der Polstreureaktanz in den Ersatzschaltbildmodellen für Maschinen mit explizit ausgeführtem Dämpferkäfig nicht garantiert. Für Einphasenschenkelpolmaschinen ist darüber hinaus keine Darstellung mit bezogenen Parametern existent gewesen, sodass in dieser Arbeit die Modifikation der bekannten Modelle erfolgt, um auch die Einphasenmaschine der bezogenen Darstellung zugänglich zu machen. Weiterhin wird eine Methode entwickelt, die Polstreureaktanz näherungsweise simulativ zu ermitteln und dadurch die Stromverläufe äquivalenter Wicklungen in absoluter und bezogener Darstellung für sowohl für Ein- als auch für Dreiphasenmaschinen anzugleichen. Die zu parametrierende Maschine wird zunächst virtuell konstruiert und durch einen genetischen Algorithmus so lange optimiert, bis sie anhand weniger vorgegebener Zielkriterien der realen Maschine am nächsten kommt. Grundlage stellt ein aus der Fachliteratur recherchierter und in einigen Teilen in dieser Arbeit komplettierter Entwurfsprozess für Schenkelpolmaschinen dar. Dieser Entwurfsprozess wird durch die Entwicklung von grafischen Annäherungsfunktionen in seiner Genauigkeit deutlich verbessert, in dem diese die Stromverläufe der absoluten und bezogenen Parameterebene angleichen. Die Funktionsweise des erarbeiteten Verfahrens wird anhand von 13 realen Referenzmaschinen validiert, die durch den zusammengeführten und vervollständigten Entwurfsprozess allesamt exakt parametriert werden können. Weitere in der Dissertation entwickelte Möglichkeiten zur vereinfachten Parameterermittlung sind Vorgaben von vektoriellen Größen als Messgrößen oder von geometrischen Abmessungen für den Algorithmus. Das so entwickelte valide Verfahren stellt die Basis für weitergehende Optimierungsansätze dar. Der technische und wirtschaftliche Mehrwert besteht in einer Unterstützung bisheriger Parameteridentifikationsverfahren nach DIN EN 60034-4. Durch eine Kopplung mit einem zweiten Genetischen Algorithmus werden exemplarisch für alle Maschinen diejenigen Messungen aus der Norm identifiziert, die mindestens benötigt werden, damit unter Zuhilfenahme des in dieser Arbeit entwickelten Verfahrens die Maschine korrekt parametriert werden kann. Der ermittelte reduzierte Messaufwand wird auf alle Maschinen erfolgreich adaptiert bei gleichbleibender Ergebnisgüte hinsichtlich dynamischer Strom- und Spannungsverläufe. Mit dem Verfahren kann die Anzahl der durchzuführenden Messungen an der realen Maschine deutlich gesenkt werden.:INHALTSVERZEICHNIS Inhaltsverzeichnis I Verzeichnis über verwendete Formelzeichen V Abkürzungsverzeichnis X Abbildungsverzeichnis XI Tabellenverzeichnis XV 1 Einleitung 1 1.1 Hintergrund 1 1.2 Stand der Technik bei der Parameterermittlung 2 1.3 Hauptaugenmerk der Arbeit 3 1.3.1 Parameteridentifikation 3 1.3.2 Modellübernahme und Parametertransformation 4 1.3.3 Abgrenzung des Themas 4 1.4 Vorgehensweise und Methodik 5 1.5 Resultierender Forschungsbedarf 7 2 Theoretische Grundlagen zur Modellbildung der Synchronmaschine 8 2.1 Zielstellung und Ausgangslage 8 2.2 Parameterebenen der Synchronmaschine 9 2.2.1 Standardisiertes Ersatzschaltbild und dessen Parameter 9 2.2.2 Parameterebenen und deren Berechnungsmöglichkeiten 10 2.3 Modellbeschreibung der Synchronmaschine 13 2.3.1 Maschinenmodell auf Basis der Hauptflussverkettungen 13 2.3.2 Gleichungssystem der Synchronmaschine im dq-System 16 2.3.3 Bezugsgrößen und ihre Umrechnung in absolute Parameter 18 2.3.4 Anpassen des Drehphasenmodells für Einphasenmaschinen 21 2.3.5 Transformationsbeziehungen 23 2.4 Simulationsmodell der Synchronmaschine 28 2.4.1 Modellübersicht 28 2.4.2 Kurzbeschreibung der Maschinenmodelle 29 2.4.3 Lasteinprägung in das Synchronmaschinenmodell 31 2.4.4 Numerische Lösung des Differentialgleichungssystems 35 2.4.5 Vergleich der dynamischen Simulation zwischen absoluter und bezogener Parameterebene 36 2.5 Notwendige Primärdaten zur Berechnung der Simulationsparameter 38 2.5.1 Darstellung der Versuche aus der Norm 38 2.5.2 Ablaufplan 39 2.5.3 Formelsatz zur exakten Bestimmung der Rotorwiderstände und der gemeinsamen Polstreureaktanz 41 2.6 Haupteinflussgrößen auf die dynamische Simulation und deren Güte 42 2.6.1 Einleitung 42 2.6.2 Diskussion der Simulationen 43 2.6.3 Erkenntnisse 50 3 Konstruktiver Aufbau der Synchronmaschine 52 3.1 Zielstellung und Ausgangslage 52 3.2 Stator- und Rotorelemente 52 3.2.1 Grundlegender Aufbau 52 3.2.2 Wicklungsaufbau 54 3.2.3 Statorwicklungsaufbau bei Einphasen- und Dreiphasenmaschinen 57 3.3 Rotorkonstruktion und Polwicklungen 58 3.3.1 Konstruktiver Aufbau 58 3.3.2 Polform 59 3.3.3 Varianten der Erregerwicklung 61 3.3.4 Varianten der Dämpferwicklung 62 3.3.5 Trägheitsmoment 66 3.4 Zusammenstellung der verschiedenen Maschinenarten 68 3.4.1 Ausblick 68 3.4.2 Vereinfachungen 68 4 Beschreibung der Entwurfsrechnung 70 4.1 Zielstellung und Ausgangslage 70 4.2 Absolute Parameter und ihre Berechnung 71 4.2.1 Einleitung 71 4.2.2 Formelsatz zur Berechnung der absoluten Parameter 72 4.3 Berechnung der Hauptinduktivitäten 74 4.3.1 Ablaufplan bei der Ermittlung 74 4.3.2 Ermittlung der Längs- und Querinduktivitäten 75 4.3.3 Bestimmung der Hauptabmessungen 75 4.3.4 Ermittlung der Statorstreuinduktivität 78 4.4 Berechnung der Erregerwicklung 83 4.4.1 Berechnung des notwendigen Leiterquerschnitts der Erregerwicklung 83 4.4.2 Berechnung der Bezugsgrößen und des Übersetzungsverhältnisses 88 4.5 Berechnung der Dämpferwicklung 89 4.5.1 Maschinen mit künstlich ausgeführtem Dämpferkäfig 89 4.5.2 Maschinen mit natürlicher Dämpfung 92 4.6 Mechanische Auslegung – Trägheitsmoment 92 4.6.1 Einleitung 92 4.6.2 Empirische Näherungsformel 93 4.7 Flexible Parameter 95 5 Der Genetische Algorithmus als Steuerungsmodul des Entwurfgangs 97 5.1 Übersicht 97 5.1.1 Grundsätzliche Funktionsweise eines Evolutionären Algorithmus 97 5.1.2 Anforderungen an den Optimierungsalgorithmus 98 5.2 Konkrete Anwendung auf den Entwurfsprozess 100 5.2.1 Übersicht 100 5.2.2 Zielkriterien 101 5.2.3 Konvergenzkriterien 103 5.2.4 Mehrfache Berechnung der Maschinen 104 6 Validierungsprozess 106 6.1 Vorhandene Datenlage und Komplettierung der Parametersätze 106 6.1.1 Zielstellung 106 6.1.2 Analyse des Maschinenparks 107 6.1.3 Grundeinstellungen 109 6.2 Nachrechnen der bezogenen Parameter unter Berücksichtigung der Polstreureaktanz 111 6.2.1 Zielstellung 111 6.2.2 Simulation mit Standardzielkriterien 113 6.2.3 Optimierung der Zielkriterien mittels grafischer Angleichung 119 6.2.4 Größenordnung der gemeinsamen Polstreureaktanz 128 6.2.5 Berechnung des Trägheitsmomentes 131 6.3 Validierung der absoluten Parameterebene 132 6.3.1 Referenzparameter der absoluten Parameterebene 132 6.3.2 Vergleich mit den berechneten Modelldaten 132 6.4 Parameterermittlung durch Vorgabe eines Messverlaufs 134 6.4.1 Messverlauf 134 6.4.2 Ergebnisse bei Vorgabe des Erregerstroms 136 6.5 Bestimmung der Minimalversuche 139 6.5.1 Zielstellung und Vorbereitung 139 6.5.2 Simulationsaufbau 140 6.5.3 Simulation 142 6.5.4 Anwendung der Minimalparametersätze auf den Maschinenpark 151 7 Zusammenfassung 154 7.1 Zielstellung der Arbeit 154 7.1.1 Entwicklung eines Verfahrens zur Parametrierung von Schenkelpolmaschinen 154 7.1.2 Schlussfolgerungen 155 7.2 Beantwortung der Forschungsfragen 156 7.3 Modellkritik und Ausblick 158 Literaturverzeichnis 160 Verzeichnis über Anhänge 164 VERZEICHNIS ÜBER ANHÄNGE A Weiterführende Maschinenberechnung 166 A.1 Berechnung der Koppel- und Eigeninduktivitäten des Erreger- und Dämpferstromkreises 166 A.2 Berechnung der Wicklungsfaktoren für die Dämpferwicklung 167 A.3 Berechnung der Streuziffern für die Dämpfer- und Erregerwicklung 169 B Tabellen zur Grafischen Konvergenz 176 B.1 Versuch ohne Grafische Konvergenz 176 B.2 Versuch GK I 176 B.3 Versuch GK II 176 B.4 Versuch GK III 177 C Versuche zur Polstreureaktanz 178 C.1 Erläuterungen 178 C.2 Rotorgrößen bei Vorgabe der Polstreureaktanz 178 D Einfluss der Polstreureaktanz auf den Entwurfsprozess 180 D.1 Erläuterungen 180 D.2 Rotorgrößen – Vergleich dynamische Simulation absolute und bezogene Parameterbene mit Polstreureaktanz 180 D.3 Rotorgrößen – Vergleich dynamische Simulation absolute und bezogene Parameterbene ohne Polstreureaktanz 185 E Versuche zu Messverläufen 190 E.1 Erläuterungen 190 E.2 Statorgrößen 190 E.3 Rotorgrößen 192 F Versuche zu Minimalversuchen 194 F.1 Erläuterungen 194 F.2 Statorgrößen 194 F.3 Rotorgrößen 196 G Ermittelte Referenzparameter anhand der PU-Werte der Datenblätter 198 G.1 Erläuterung 198 G.2 Maschinensätze 198
49

On The Mechanical Design of Power Dense Axial Flux Permanent Magnet Synchronous Motors for Aircraft Propulsion Applications

Duperly, Federico January 2024 (has links)
Traffic congestion in large urban and metropolitan areas is a substantial problem plaguing these areas. Not only are commuters losing valuable time, but greenhouse gas emissions are substantially worse because of congestion. Considerable research and development into next generation electrified aircraft is ongoing to introduce air mobility as a viable new means of transporting people and goods across long commutes. This development extends into commercial aviation as a whole as a means of reducing the industry’s carbon footprint with new aircraft designs that employ electrified propulsion systems. Many electrified aircraft projects are currently underway, ranging from small commuter aircraft all the way to large twin-aisle aircraft, and part of the development scope for alot of these projects is creating highly robust and power dense electric machines that replace the current state-of-the-art. The axial flux permanent magnet synchronous machine is an exciting candidate for aircraft propulsion due to its exceptional torque density and compact axial nature. In this thesis, the mechanical design for three generations of axial flux permanent magnet synchronous machines is discussed. These machines serve as development phase prototypes for machines that are ultimately intended for propulsion applications in commercial aviation, particularly for eVTOL aircraft. The motivation for electrification in the commercial aviation industry is discussed, followed by an overview of the development landscape for electrified propulsion systems in commercial aviation, focusing primarily on electric machines that are currently state-of-the-art or are set to be in the near future, as well as what is required for future electric machines in terms of power output and power density. The axial flux architecture is then presented, including a high-level comparison to the radial-flux architecture, an overview of the various axial flux machine designs and topologies, and a discussion of the inherent mechanical design challenges associated with the axial flux architecture. The yokeless and segmented armature axial flux permanent magnet synchronous machine design was selected for the machines developed as part of the research for this thesis, and the discussion of the mechanical design of these machines is broken up into the two core sub assemblies: stator assembly and rotating assembly. High-level design methodologies are introduced for both sub-assemblies, which is further broken down into different approaches pertaining to each generation. The first and second generation designs are presented at a high level, followed by deep-dives into the complete mechanical design for the third generation stator, the bearing selection, arrangement, and analysis for the third generation rotating assembly, and adhesive characterization trials used to guide adhesive selection for rotor magnetics retention in the second and third generation machines. The current status of the machines and any outcomes from testing that has been conducted thus far, particularly with respect to performance, is presented at the end. / Thesis / Master of Applied Science (MASc)
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Position-sensorless control of permanent magnet synchronous machines over wide speed range

Chi, Song 30 August 2007 (has links)
No description available.

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