Дисертації з теми "Magnet losse"
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Ng, Kong. "Electromagnetic losses in brushless permanent magnet machines." Thesis, University of Sheffield, 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.579745.
Повний текст джерелаAtallah, Kais. "Iron losses in brushless permanent magnet DC machines." Thesis, University of Sheffield, 1993. http://etheses.whiterose.ac.uk/14941/.
Повний текст джерелаLi, Zhou, of Western Sydney Nepean University, and of Mechatronic Computer and Electrical Engineering School. "Numerical computation of core losses in permanent magnet machines." THESIS_XXXX_MCEE_Li_Z.xml, 2000. http://handle.uws.edu.au:8081/1959.7/284.
Повний текст джерелаMaster of Engineering (Hons)
Mi, Chunting. "Modelling of iron losses of permanent magnet synchronous motors." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2001. http://www.collectionscanada.ca/obj/s4/f2/dsk3/ftp04/NQ58959.pdf.
Повний текст джерелаGarcia, Gonzalez Adolfo. "Magnet Losses in Inverter-fed High-speed PM Machines." Thesis, KTH, Elektrisk energiomvandling, 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-177641.
Повний текст джерелаDetta examensarbete handlar om uppskattningen av magnetforluster i en permanentmagnetmotor (PM) inford i en mutterdragare. Denna typ av maskin har intressantafunktioner, som att den ar slot-less och att den kors i en hog hastighet (30000rpm). En omfattande litteraturstudie utfordes for att kunna uppskatta forluster imagneterna pa basta satt. Forst presenteras analytiska modeller for att berakna denelektromotoriska kraften (EMK) och den magnetiska odestatheten i luftgapet somuppkommer pa grund av strommarna i statorn. Dessutom har era av de analytiskamodellerna for berakning av forlusterna som beskrivits i litteraturen testats och anpassatstill en slot-less maskin med en parallelmagnetiserad ring. En numerisk uppskattningav forlusterna har sedan utforts med hjalp av nita elementmetoden (FEM) 2D.Dartill har en detaljerad undersokning genomforts hur olika parameterinstallningarpaverka utfallet. De FEM parametrar som har undersokts har bland annat bestattav berakningsnatets storlek, tidssteg, remanens odestatheten i magneten och om superpositionav forlusterna galler. Till sist har berakningar for forluster med 3D FEMutforts och jamforts med resultaten for bade de analytiska och FEM 2D resultaten.Uppskattning av forluster innefattar variationen av dessa med ett frekvensomrade mellan10 och 100 kHz.
Li, Zhou. "Numerical computation of core losses in permanent magnet machines." Thesis, View thesis, 2000. http://handle.uws.edu.au:8081/1959.7/284.
Повний текст джерелаLi, Zhou. "Numerical computation of core losses in permanent magnet machines /." View thesis, 2000. http://library.uws.edu.au/adt-NUWS/public/adt-NUWS20030901.113715/index.html.
Повний текст джерела"Submitted for the degree of Master of Engineering (Hons), School of Mechatronic, Computer & Electrical Engineering, University of Western Sydney, Nepean" Includes bibliographical references (leaves 107-114).
Vaez, Sadegh. "Loss minimization control of interior permanent magnet motor drives." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1997. http://www.collectionscanada.ca/obj/s4/f2/dsk3/ftp04/nq22499.pdf.
Повний текст джерелаIrenji, Neamat Taghizadeh. "Calculation of electromagnetic rotor losses in high-speed permanent magnet machines." Thesis, University of Southampton, 1998. https://eprints.soton.ac.uk/47948/.
Повний текст джерелаNiu, Xin. "Traction machine winding and magnet design for electric vehicles." Thesis, University of Manchester, 2017. https://www.research.manchester.ac.uk/portal/en/theses/traction-machine-winding-and-magnetdesign-for-electric-vehicles(df8dfe16-71cb-48ee-b270-b90b3a24617e).html.
Повний текст джерелаXue, Shaoshen. "Investigation of iron losses in permanent magnet machines accounting for temperature effect." Thesis, University of Sheffield, 2017. http://etheses.whiterose.ac.uk/19064/.
Повний текст джерелаQazalbash, Arfakhshand. "Rotor eddy current power losses in high speed permanent magnet synchronous generators." Thesis, University of Southampton, 2014. https://eprints.soton.ac.uk/364580/.
Повний текст джерелаRajput, Mihir N. "Thermal modeling of permanent magnet synchronous motor and inverter." Thesis, Georgia Institute of Technology, 2016. http://hdl.handle.net/1853/55053.
Повний текст джерелаSreedharan, Nair Sreeju. "Rotor eddy current loss prediction and demagnetization assessment in permanent magnet machines." Thesis, University of Sheffield, 2017. http://etheses.whiterose.ac.uk/16067/.
Повний текст джерелаLamperth, Michael. "An investigation into the mechanical and electrical losses of permanent magnet disc machines." Thesis, Imperial College London, 2000. http://hdl.handle.net/10044/1/8648.
Повний текст джерелаYu, Anshan. "An investigation of torque density and losses in high-speed permanent magnet machines." Thesis, University of Sheffield, 2018. http://etheses.whiterose.ac.uk/20606/.
Повний текст джерелаTaghizadeh, Kakhki Mehdi. "Modeling of losses in a permanent magnet machine fed by a PWM supply." Doctoral thesis, Université Laval, 2016. http://hdl.handle.net/20.500.11794/27358.
Повний текст джерелаIn order to respect the constraints for efficiency in an electrical machine, losses should be accurately estimated. In the case of a permanent magnet machine fed by a PWM supply, the high frequency harmonic content of the current (associated with the modulation scheme), may generate additional losses in the machine which the conventional models tend to overlook. Development of new models which may take account of these additional losses will allow us to improve the analysis and design of the electrical machines. In this work various models for the prediction of losses in a permanent magnet machine including the mechanical losses, copper losses and magnetic losses are presented. A new loss expression for taking account of the skin effect in a laminated magnetic material due to high frequency harmonic content of the stator current is developed. Regarding hysteresis losses, an algorithm for the identification of the minor hysteresis cycles is presented. An analytical model for the estimation of the PWM losses in the stator of the permanent magnet machine, and a new method for the direct estimation of eddy current losses in the lamination material by 2D-FE analysis are also developed. The design methodology for the design of a surface mounted permanent magnet machine is briefly described. A prototype machine is designed and realised to measure the losses in a variety of operating conditions and validate the loss models. Various models for magnetic losses are compared in order to find the most appropriate method in the time or frequency domains. The method which offers the best performance is then validated in a wide range of operating conditions. The losses in two PM rotors (with or without magnet segmentation) are compared and the effect of magnet segmentation and the choice of rotor yoke material are investigated by 2D FE analysis. These results are also used to evaluate the performance of an analytical model for the prediction of eddy current losses in the rotor magnets.
Bruzzone, Pierluigi. "AC losses in high current superconductors for nuclear fusion magnets /." [S.l.] : [s.n.], 1987. http://e-collection.ethbib.ethz.ch/show?type=diss&nr=8224.
Повний текст джерелаCavallucci, Lorenzo <1989>. "Thermal Stability and AC Losses in High-Field Superconducting Magnets." Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2018. http://amsdottorato.unibo.it/8683/1/PhD_Thesis_Cavallucci.pdf.
Повний текст джерелаMonajemy, Ramin. "Control Strategies and Parameter Compensation for Permanent Magnet Synchronous Motor Drives." Diss., Virginia Tech, 2000. http://hdl.handle.net/10919/11247.
Повний текст джерелаPh. D.
NEVOLOSO, Claudio. "Enhanced mathematical modelling of interior permanent magnet synchronous machines for loss minimization control." Doctoral thesis, Università degli Studi di Palermo, 2020. http://hdl.handle.net/10447/395194.
Повний текст джерелаYang, Jian. "Prediction of the power losses of PWM inverter drives for permanent magnet synchronous motors." Thesis, This resource online, 1995. http://scholar.lib.vt.edu/theses/available/etd-06112009-063124/.
Повний текст джерелаWalker, Jill Alison. "Aspects of magnetisation and iron loss characteristics in switched-reluctance and permanent-magnet machines." Thesis, University of Glasgow, 2006. http://theses.gla.ac.uk/1621/.
Повний текст джерелаSoroka, Pavlo. "Electric vehicle drivetrain based on permanent magnet synchronous motor with loss minimization control algorithm." Master's thesis, Igor Sikorsky Kyiv Polytechnic Institute, 2020. https://ela.kpi.ua/handle/123456789/39262.
Повний текст джерелаThe thesis comprises: 93 pages, 32 figures, 32 tables, and graphical part on 6 pages A1. The thesis aims to develop the method of calculating the parameters of the electric vehicle drivetrain, based on a permanent magnet synchronous motor. Parameters of traction motor, battery pack, and control circuit elements of the electric vehicle drivetrain were calculated. Loss minimization control algorithm for interior permanent magnet synchronous motor was developed. Electromechanical system performance characteristics were studied by mathematical simulation. The efficiency of the developed control algorithm was compared with the conventional vector control method.
Wills, Dominic. "Methods to quantify and reduce rotor losses in a solid rotor yoke permanent magnet machine." Thesis, Stellenbosch : University of Stellenbosch, 2010. http://hdl.handle.net/10019.1/4014.
Повний текст джерелаENGLISH ABSTRACT: Certain types of electric machines are particularly susceptible to the proliferation of eddy currents flowing within the solid conducting regions in the rotor. Single-layer, non-overlapping windings within uneven open slots are some stator properties that can produce damaging, asynchronous magnetic field harmonics which manifest in the rotor as eddy currents. The ohmic losses caused by these eddy currents are a source of inefficiency and can cause a marked increase in the temperature of the rotor. This temperature rise can be dangerous for the magnets, which have to be kept within temperature limits to avoid partial or full demagnetization. The research work presented here is concerned with reducing the effect of eddy currents in the rotor magnets and solid rotor yoke of an electric machine. The work presents analytical methods to calculate the magnetic fields, eddy currents and solid loss in an electric machine due to current in the winding and due to the interaction of the permeance variation in the stator with the magnets in the rotor. A method is also suggested where the analytical theory can be used with a magnetostatic finite element solution to produce a transient solid loss result. The research work also investigates a method for optimal segmentation in both level and penetration, and provides some design suggestions. The work presents the method of partial magnet segmentation, which is a technique whereby thin incisions are made into the magnet material from one or both sides. Another method of partial rotor segmentation is also presented where the incisions are made into a portion of the magnet-facing solid yoke. These methods attempt to interrupt the flow of eddy currents and increase the resistance ‘seen’ by the eddy currents, while also keeping construction difficulty and cost to a minimum. The methods are verified using finite element calculations which are compared to measured results. The result is that partial magnet segmentation is a very useful, effective and practical method of segmenting magnets. The loss reduction profile can be similar to that of traditional full segmentation. The method of partial rotor segmentation also shows a large reduction in rotor power loss. With implementation of these methods on a test machine, one can expect an efficiency increase of more than 4 %
AFRIKAANSE OPSOMMING: Sekere tipes van elektriese masjiene is veral sensitief vir die vloei van werwelstrome in solied geleidende gebiede in die rotor. Enkellaag, nie-oorvleuelende wikkelings in oneweredige oop gleuwe is enkele stator eienskappe wat skadelike, asinchrone magneetveld harmonieke tot gevolg kan hê, wat as werwelstrome in die rotor manifesteer. Die ohmiese verliese wat deur hierdie werwelstrome teweeg gebring word is 'n bron van ondoeltreffendheid en kan lei tot 'n merkbare toename in die temperatuur van die rotor. Hierdie temperatuur styging hou gevaar in vir die magnete en moet binne temperatuur limiete gehou word om gedeeltlike of self volle demagnetisering te vermy. Die navorsing vervat in hierdie document is gemoeid met die vermindering van die effek van werwelstrome in die rotor magnete en in die soliede rotor juk van 'n elektriese masjien. Die werk bied analitiese metodes aan vir die berekening van die magneetvelde, werwelstrome en soliede verliese in ’n elektriese masjien as gevolg van strome in die wikkelings en die interaksie van die permeansie variasie van die stator met die magnete in die rotor. ’n Metode word ook voorgestel waar die analitiese teorie saam met ’n magnetostatiese eindige element oplossing gebruik word om ’n resultaat vir die oorgang soliede verliese te verkry. Die navorsingswerk ondersoek ook ’n metode vir die optimale segmentering in beide vlak sowel as penetrasie, en verskaf sekere ontwerp voorstelle. Die werk bied die metode aan van gedeeltelike magneet segmentering, wat 'n tegniek is waarvolgens dun insnydings gemaak word aan een of beide kante van die magneet materiaal. Nog ’n metode van gedeeltelike rotor segmentering word beskou waar die insnydings in in ’n gedeelte aan die magneetkant van die soliede rotor juk gemaak word. Hierdie metodes poog om die vloei van werwelstrome te onderbreek en die weerstand soos "gesien" deur die werwelstrome te verhoog, terwyl konstruksie kompleksiteit en koste tot ’n minimum beperk word. Die metodes word bevestig deur eindige element berekeninge wat met gemete resultate vergelyk word. Die gevolg is dat gedeeltelike magneet segmentering 'n baie nuttige, doeltreffende en praktiese metode van die segmentering van magnete is. Die verliesverminderingsprofiel van gedeeltelike segmentering kan soortgelyk wees aan dit van tradisionele volle segmentering. Die metode van gedeeltelike rotor segmentering toon ook 'n groot afname in rotor drywingsverlies. Met die implementering van hierdie metodes op ’n toetsmasjien, kan ’n mens ’n verhoging in benuttingsgraad verwag van meer as 4 %
Yao, Yue. "Power Loss Modelling and Implementation of Permanent Magnet Synchronous Motor Drive under Variable Current Excitation." Thesis, The University of Sydney, 2015. http://hdl.handle.net/2123/14281.
Повний текст джерелаXu, Ye. "Kilowatt Three-phase Rotary Transformer Design for Permanent Magnet DC Motor with On-rotor Drive System." Thesis, Mittuniversitetet, Avdelningen för elektronikkonstruktion, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:miun:diva-27781.
Повний текст джерелаKubenka, Marek. "Model synchronního motoru s permanentními magnety se ztrátami." Master's thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2011. http://www.nusl.cz/ntk/nusl-219035.
Повний текст джерелаLouzguiti, Alexandre. "Magnetic screening currents and coupling losses induced in superconducting magnets for thermonuclear fusion." Thesis, Aix-Marseille, 2017. http://www.theses.fr/2017AIXM0574.
Повний текст джерелаTokamaks aim at producing energy by thermonuclear fusion heating a hydrogen plasma up to 150 million K and confining it with an intense magnetic field created by magnets carrying important currents. Superconductivity is a very valuable asset in this field since it allows to reduce the size of the magnets and their energy consumption in exchange for cooling them down to cryogenic temperatures. However, in tokamaks, magnetic field variations occur (e.g. due to the central solenoid discharge) and generate induction losses in the magnets. If their temperature increases too much, they lose their superconducting properties in a brutal transition called "quench": to protect their integrity, they are then discharged and the magnetic confinement of the plasma is lost. We have therefore focused on the modeling of these losses - more precisely on the “coupling losses” - since their knowledge is crucial to safely adapt the cryogenic cooling of the magnets and predict the operating limits of the tokamak. In order to both enhance the physical understanding of this complex phenomenon and provide simple but realistic solutions that can easily be integrated in multiphysics platforms already heavily solicited by the modeling of other effects, we have chosen to adopt an analytical approach on this problem. The cables commonly considered for tokamaks presenting a rather complex architecture (several hundreds of strands twisted together in specific patterns), we have carried out analytical and experimental studies at the different scales of the cable; we then compare the results of our approach to other existing ones (e.g. numerical models) and, when possible, to the experiment
Chin, Yung-Kang Robert. "A permanent magnet traction motor for electric forklifts : design and iron loss analysis with experimental verifications /." Stockholm : Division of Electrical Machines and Power Electronics, School of Electrical Engineering, Royal Institute of Technology, 2006. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-4241.
Повний текст джерелаLazraq, Byström Joseph. "Characterization of Magneto-Dielectric Materials for Microwave Devices." Thesis, Uppsala universitet, Fasta tillståndets elektronik, 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-419515.
Повний текст джерелаKrings, Andreas. "Iron Losses in Electrical Machines - Influence of Material Properties, Manufacturing Processes, and Inverter Operation." Doctoral thesis, KTH, Elektrisk energiomvandling, 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-145243.
Повний текст джерелаQC 20140516
Xie, Wei [Verfasser]. "Loss Minimizing Strategy of Permanent Magnet Synchronous Machines using Improved Direct Torque and Flux Control / Wei Xie." Aachen : Shaker, 2015. http://d-nb.info/1080763384/34.
Повний текст джерелаDeeb, Ramia. "Tepelné výpočty motorů s permanentními magnety v silnoproudé elektrotechnice." Doctoral thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2013. http://www.nusl.cz/ntk/nusl-233596.
Повний текст джерелаLippi, Silvio. "Analysis of rotor eddy-current losses in synchronous motors." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2022.
Знайти повний текст джерелаWilson, Brian Christopher David. "Control Designs for Low-Loss Active Magnetic Bearing: Theory and Implementation." Diss., Available online, Georgia Institute of Technology, 2004:, 2004. http://etd.gatech.edu/theses/available/etd-04122004-133631/unrestricted/wilson%5Fbrian%5Fc%5F200405%5Fphd.pdf.
Повний текст джерелаHabetler, Thomas, Committee Member ; Sadegh Nader, Committee Member ; Taylor David, Committee Member ; Tsiotras Panagiotis, Committee Co-Chair ; Heck-Ferri Bonnie, Committee Co-Chair. Vita. Includes bibliographical references (leaves 319-326).
Fasolo, Alessandro. "Multi Polar Direct Drive Permanent Magnet Synchronous Machines for Renewable Energy." Doctoral thesis, Università degli studi di Padova, 2013. http://hdl.handle.net/11577/3423088.
Повний текст джерелаQuesto lavoro di dottorato considera principalmente la Risorsa Eolica e si focalizza sulle caratteristiche elettromagnetiche dei generatori a presa diretta per questa applicazione. Malgrado molti Costruttori di turbine eoliche usino congurazioni comprendenti il moltiplicatore di giri, la presenza di quest'organo di trasmissione causa una perdita di ecienza del sistema elettromeccanico che va a comprometterne la sostenibilità. Una soluzione multipolare a bassa velocita di rotazione e presa diretta tra generatore e pale della turbina e quindi adottata. Si sceglie l'utilizzo del magnete permanente grazie alla sua compattezza e all'assenza di spazzole in paragone alle soluzioni di macchina sincrona tradizionale. L'avvolgimento frazionario e adottato per risparmiare materiale nell'avvolgimento di armatura della macchina. Questo tipo di congurazione presenta evidenti vantaggi come la lunghezza ridotta delle testate, il buon fattore di riempimento delle cave, elevati rendimento e fattore di potenza. Essa si presta inoltre a soluzioni circuitalmente ridondanti che consentono una struttura modulare della parte attiva, con la capacita di tollerare i guasti. D'altro canto, le armoniche spaziali della forza magneto motrice (MMF) dovuta all'avvolgimento frazionario causano perdite nel rotore di entita notevole. I metodi tradizionali di calcolo delle perdite (formula di Steinmetz o modelli di corpi solidi in campo magnetico uniforme) non forniscono risultati soddisfacenti per queste perdite. La forza magneto motrice risulta non sincrona con il rotore della macchina, con conseguente indursi di correnti parassite in ogni parte conduttrice del rotore, come nel giogo metallico che sorregge i poli magnetici e nei magneti stessi (terre rare). Le perdite nei magneti ne causano il riscaldamento, con conseguente calo delle prestazioni della macchina. La riduzione del campo dei magneti dovuta all'aumento di temperatura aumenta il rischio di smagnetizzazione irreversibile. L'ampiezza delle armoniche spaziali di forza magneto motrice e la loro frequenza vista dal rotore dipendono dalla particolare combinazione cave{poli dell'avvolgimento scelto. L'entita di queste perdite cresce notevolmente con l'aumentare delle dimensioni della macchina, divenendo un aspetto cruciale nella progettazione di macchine multipolari a presa diretta di grande diametro (. 2m) con magnete permanente. Una scelta adeguata del rapporto cave{poli dell'avvolgimento, signica un notevole miglioramento della sostenibilita del processo di conversione elettromeccanica: le perdite vengono ridotte e il rendimento migliora. Se il rendimento migliora, signica che meno materiale e stato sprecato. Questa parte del lavoro di tesi si e svolta presso il Laboratorio di Azionamenti Elettrici nel Dipartimento di Ingegneria Industriale dell'Universita di Padova nell'ambito di un contratto di ricerca voluto da Leitwind SpA (VIpiteno, Italia). Leitwind e un costruttore di turbine eoliche. Lo scopo e progettare un generatore di grande diametro (v 4m) per il prototipo di turbina eolica da 3 MW. Compresa l'importanza del fenomeno delle perdite rotoriche, la volonta di Leitwind e svilupparne calcolo per scegliere l'avvolgimento della nuova macchina. Il generatore Leitwind esitente, denominato LW15C, per la turbina LTW77 (potenza nominale 1.5 MW) e analizzato sia con modelli analitici che con gli elementi niti. Questo generatore e la base di partenza di questo studio. Viene applicato un metodo per il calcolo delle perdite rotoriche indotte dall'elevato contenuto armonico dell'avvolgimento frazionario. Le perdite cos ottenute sono confrontate con i risultati dell'attivita del banco prova su macchine reali. Con lo stesso approccio si studia e si modella il motore diretto per trazione funiviaria SFA (500 kW di potenza nominale) negli impianti Leitner. Leitner e Leitwind appartengono al Gruppo Leitner Technologies. I risultati del banco prova sono confrontati con i valori calcolati. La progettazione del nuovo generatore LW30A e sviluppata a partire dai modelli creati per il generatore LW15C e il motore diretto SFA. Vengono poi studiate dierenti topologie di macchina a magnete permanente con avvolgimento frazionario per confrontarle con la congurazione switching ux (SFPM). Lo studio prende in considerazione sia magneti di terre rare, che di ferrite. La possibilità di integrare una notevole quantita di magnete nella parte di armatura della macchina SFPM e il principio di concentrazione di usso portano ad una soluzione con un buon rapporto costi prestazioni, che pero deve essere valutata non solo da un punto di vista di prestazioni. La struttura del rotore di questa macchina e semplice e robusta, come per le macchine a riluttanza. Il comportamento della topologia SFPM a smagnetizzazione dei magneti permanenti risulta un punto cruciale da indagare. Per allargare lo studio ad un'altra Fonte Rinnovabile, l'energia da moto ondoso e brevemente descritta e vengono confrontate alcune topologie di generatori lineari per questa applicazione. Uno struttura a doppio statore viene studiata con l'intento di massimizzare la spinta sulla parte mobile. Si considera inoltre l'utilizzo dei magneti in ferrite: malgrado il loro basso prodotto di energia rispetto ai magneti in terre rare, essi risultano meni nocivi per l'ambiente e la salute dell'uomo: il processo di estrazione delle terre rare coinvolge infatti elementi radioattivi, mentre l'estrazione della ferrite e in tutto simile a quella del ferro. Contributi principali della tesi I principali contributi di questo lavoro di tesi alla ricerca futura nell'ambito delle energie rinnovabili si possono cos sintetizzare: • L'applicazione del modello a strati e del metodo dei punti corrente nel calcolo delle perdite rotoriche di macchine elettriche a presa diretta di grande diametro, con magneti permanenti. I risultati dell'attivita sperimentale su banco prova di grosse macchine reali sono confrontati con i valori calcolati. • La scelta del numero di poli e di cave nella progettazione di macchine a presa diretta di grande diametro, con avvolgimento frazionario. • Confronto della macchina switching ux con topologie di macchina note, comprendendo la smagnetizzazione del magnete e l'utilizzo della ferrite, materiale più sostenibile delle terre rare. • Studio di diverse topologie di generatore lineare per generazione da moto ondoso, includendo la topologia switching ux a doppio statore. Struttura della tesi Capitolo 1 : presenta una breve panoramica sull'energia rinnovabile eolica e da moto ondoso e descrive l'azienda Leitwind SpA. Capitolo 2 : descrive la modellazione e l'analisi delle macchine studiate, sia con metodi analitici che con gli elementi niti: sono inclusi i risultati dell'attivita sul banco prova. I modelli, sviluppati sul generatore LW15 e sul motore SFA sono poi applicati al nuovo generatore LW30A. Capitolo 3 : aronta la tematica del calcolo delle perdite rotoriche, sviluppando il modello a strati e il metodo dei punti corrente. Viene descritto il calcolo delle perdite rotoriche. Si aronta la validazione dei metodi di calcolo al banco prova. Capitolo 4 : ricava una legge di scala per le perdite rotoriche per macchine a magnete permanente ad avvolgimento frazionario. Capitolo 5 : presenta la scelta del rapporto cave{poli nel progetto del nuovo generatore LW30A per la turbina da 3.0 MW LTW 101. Viene investigata la possibilità di applicare l'Indice delle Perdite Rotoriche, ricavato dal modello a strati. Capitolo 6 : confronta diverse topologie di macchine ad avvolgimento frazionario con la congurazione switching ux, sia con terre rare che con ferrite. Si aronta il fenomeno della smagnetizzazione sulle diverse topologie di macchina. Capitolo 7 : prende in considerazione topologie di macchina lineare per conversione da moto ondoso. Include la congurazione switchng ux a doppio statore
Bulín, Tomáš. "Analýza ztrát v elektrických strojích při nestandardních podmínkách." Doctoral thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2019. http://www.nusl.cz/ntk/nusl-408013.
Повний текст джерелаRabias, J. "Power loss in amorphous ribbon materials : The effect of surface roughness on the power loss and harmonic content of flux density of amorphous ribbon materials." Thesis, Bucks New University, 1985. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.375618.
Повний текст джерелаBeckman, Mathias, and Gerald Volden Alex Christy. "Performance Assessment of Electrical Motor for Electric Aircraft Propulsion Applications : Evaluation of the Permanent Magnet Motor and its Limitations in Aircraft Propulsion." Thesis, Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:mdh:diva-45157.
Повний текст джерелаFERRERO, RICCARDO. "Modeling of the hysteresis losses of magnetic nanostructures for hyperthermia applications." Doctoral thesis, Politecnico di Torino, 2019. http://hdl.handle.net/11583/2742523.
Повний текст джерелаNakashima, T., T. Yoshida, S. Nakata, M. Teranishi, I. M. Ishida, S. Naganawa, and M. Sugiura. "Vestibular aqueduct in sudden sensorineural hearing loss." Cambridge University Press, 2008. http://hdl.handle.net/2237/14312.
Повний текст джерелаPreuss, Jason Lee. "Design and analysis of a composite flywheel preload loss test rig." Thesis, Texas A&M University, 2004. http://hdl.handle.net/1969.1/100.
Повний текст джерелаMancini, Marilia Wellichan. "Perdas colisionais devido ao processo de mudança de estrutura fina em uma armadilha magneto-óptica de rubídio." Universidade de São Paulo, 1999. http://www.teses.usp.br/teses/disponiveis/76/76131/tde-11092007-110102/.
Повний текст джерелаWe report the observation of trap-loss collisional rates due to fine structure changing collisions between cold and trapped 85Rb atoms. We have measured, by photoionization of the atomic fragments in 5P1/2 state originated in these collisions, the rates through the atoms leave the trap induced by this loss mechanism. We carried out experiments to determine the rate dependence with the intensity of the trapping laser, and with the frequency, using the catalisys technique. We also measured the contribution of this process to the total trap-loss rate and determined that fine structure changing is not the dominant loss mechanism. It was also observed that the hyperfine structure plays an important role in the rate behavior. We compared our results with those given by a semiclassical theoretical approach, the Gallagher-Pritchard model, and some disagreements were observed. We proposed some arguments to explain these discrepancies. We believe that such results should stimulate theoretical work on this field.
Poskovic, Emir. "Innovative magnetic materials for the new applications in electrical machines." Doctoral thesis, Università degli studi di Padova, 2019. http://hdl.handle.net/11577/3424784.
Повний текст джерелаMu, Mingkai. "High Frequency Magnetic Core Loss Study." Diss., Virginia Tech, 2013. http://hdl.handle.net/10919/19296.
Повний текст джерелаIn this dissertation, two new core loss measurement methods are introduced first. These two methods use the reactive cancellation concept to reduce the sensitivity to phase discrepancy, which will destroy the accuracy in classic two-winding method for high frequency high quality factor sample measurements. By using the new measurement techniques the accuracy can be improved by several orders. The first is for sinusoidal waveforms, and the second is for non-sinusoidal wave. The new methods enable high frequency core loss characterization capability, which will help scientists and engineers on material research and inductor/transformer design. Measurement examples, considerations and error analysis are demonstrated and discussed in detail.
With the measurement techniques, the core loss under rectangular AC voltage and DC bias current are investigated. A new core loss model named rectangular extension Steinmetz equation (RESE) is proposed based on the measurement results. The new model is shown to be more accurate than the existing core loss models. Several commercially available MnZn ferrites are characterized and modeled.
Other than conventional MnZn ferrite materials, three commercial LTCC ferrite materials are characterized for integrated power supply applications. Based on characterized properties of these LTCCs, a group of new LTCC ferrites are fabricated and tested. The new LTCC is fabricated by laminating commercial LTCC tapes and co-firing. The new LTCC is demonstrated to have over 50% more inductance over the commercial LTCC materials. This work indicates that the power electronics engineers should work with material engineers to get the optimum material for a given application.
In the last part, the core loss of the partially saturated lateral flux planar inductor is analyzed. The challenge of the analysis is the complexity of the distribution of bias field and flux density in a highly biased planar inductor. Each point in the core is working at different excitation and bias condition, and the core loss density is very non-uniform. The proposed method combines the characterization tested in previous chapters and the commercial finite element tool. Experiments verified that the calculation errors are within about 10%.
In conclusion, the research in this dissertation proposed a complete solution to measure, model and analyze the high frequency core loss. This solution will not only facilitate fundamental research on physics understanding and material innovation, but also development of power electronics and RF applications.
Ph. D.
Ribbenfjärd, David. "A lumped element transformer model including core losses and winding impedances." Licentiate thesis, KTH, School of Electrical Engineering (EES), 2007. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-4307.
Повний текст джерелаIn order to design a power transformer it is important to understand its internal electromagnetic behaviour. That can be obtained by measurements on physical transformers, analytical expressions and computer simulations. One benefit with simulations is that the transformer can be studied before it is built physically and that the consequences of changing dimensions and parameters easily can be tested.
In this thesis a time-domain transformer model is presented. The model includes core losses as magnetic static hysteresis, eddy current and excess eddy current losses. Moreover, the model comprises winding losses including eddy currents, capacitive effects and leakage flux. The core and windings are first modelled separately and then connected together in a total transformer model. This results in a detailed transformer model.
One important result of the thesis is the possibility to simulate dynamic hysteresis including the eddy current shielding in the magnetic core material. This is achieved by using Cauer circuit combined with analytical expression for static and dynamic hysteresis. Thereby, all magnetic loss components in the material can be simulated accurately. This dynamic hysteresis model is verified through experiments showing very good agreement.
Jirásek, Tomáš. "Výpočet přídavných ztrát asynchronního motoru." Master's thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2013. http://www.nusl.cz/ntk/nusl-220098.
Повний текст джерелаKurfűrst, Jiří. "Optimalizace stroje s permanentními magnety na rotoru pomocí umělé inteligence." Doctoral thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2013. http://www.nusl.cz/ntk/nusl-233585.
Повний текст джерелаTsakmakidis, Kosmas L. "Ultraslow and stopped light in metamaterials." Thesis, University of Surrey, 2008. http://epubs.surrey.ac.uk/844095/.
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