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Comparative Study of Stranded and Bar Windings in an Induction Motor for Automotive Propulsion ApplicationsKoke, Hannah January 2017 (has links)
The source-to-wheel efficiency of today’s electrified vehicles already far surpasses the
efficiency of strictly gasoline vehicles. As sources of electricity become cleaner and
more efficient, and as gasoline becomes more scarce, the need for transportation electrification is increasingly economically and environmentally driven. The automotive
industry primarily makes use of permanent magnet synchronous machines (PMSMs)
and induction machines (IMs), the latter has the cost advantage of containing no rare
earth metals. This thesis studies two different induction motors for electrified powertrain
applications using a novel optimization algorithm to create efficiency maps
and compare the efficiencies of the two motors. Induction motors are difficult to
banchmark due to their complicated control schemes. Each point in their operating
range can be achieved with an infinite number of current/slip combinations and
therefore has infinite potential efficiencies. The proposed algorithm limits the number
of simulations needed to benchmark an induction machine, and provides a clear and
unbiased way to compare machines based on losses at their most efficient current/slip
combinations over their entire operating range. The proposed algorithm is able to
calculate losses within 5% accuracy of simulation values for both machines. The first
motor studied makes use of stranded windings and geometry parameters from the
Tesla Motors patents. The efficiency map created has a peak efficiency of 96% and
corresponds closely to an efficiency map for a similar motor found in literature. The
second motor makes use of copper bar windings, which are easier to manufacture and
have lower material costs. Bar windings, typically have lower resistance and stator
copper losses at low speeds, but higher effective resistance and stator losses at high
speeds due to eddy effects. The motor modelled was intended simply to compare the
stranded and bar windings, and to see the advantages and disadvantages. For this
reason, no other changes are made to the winding layout or motor geometry, including
changes that would reduce the eddy effect. The resultant efficiency map has a
peak efficiency of only 90%, performing worse than the stranded wound motor across
most of its operating range. At very low speeds, under 1000 rpm, the efficiency of
the bar wound machine is better than that of the stranded machine. The bar wound
machine also has the advantage of being over 80% efficient everywhere. The author
suggests that future research focus on applying the proposed benchmarking algorithm
to stator bar motors designed to limit eddy effects. Strategies include changing the
slot opening shape, increasing the number of stator bars, and moving the stator bars
away from the air gap. / Thesis / Master of Applied Science (MASc)
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A Study of Flat Linear Induction MachinesNolan, Paul 27 July 2016 (has links)
<p> Of greatest interest in the field of linear motion electrical
machines are, the flat linear induction motor and liquid metal pump. The
former has feasibility in high speed transportation while the latter is
becoming of increasing importance in metallurgical processes. </p> <p> This thesis examines and extends the traditional representation
for the usual sheet secondary classification and then presents a common
theory which also allows composite secondary machines to be analysed. An
idealized model is developed consisting of a number of regions representing air gaps, iron segments, and secondary conductors. A general solution
for the field quantities is obtained. The concept of wave impedance and
a transfer matrix approach allow a wide variety of configurations to be
analysed. Unlike previous work the approach developed here allows for
simultaneous investigation of lateral variation and skin effect. In the
limiting cases where in tum skin effect and lateral variation are
neglected the solutions are in agreement with known results. </p> / Thesis / Master of Engineering (MEngr)
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[pt] FUNÇÕES DE TRANSFERÊNCIA DE ORDEM REDUZIDA PARA MOTORES DE INDUÇÃO / [en] INDUCTION MOTOR REDUCED ORDER TRANSFER FUNCTIONSJUSSARA FARIAS FARDIN 18 January 2007 (has links)
[pt] Dentre as máquinas elétricas que compõem os sistemas
industriais, destacam-se hoje em dia os motores de
indução, não apenas pelo grande número em que são
encontrados como pelas capacidades cada vez maiores em que
são utilizados.
Motores e circuitos conversores e de controles podem ser
combinados de diversos modos, ressaltando-se a necessidade
de uma modelagem adequada para o sistema como um todo.
Sabe-se, de vasta literatura, que modelos simplificados da
máquina de indução como carga num sistema de potência,
traduzem com precisão suficiente seu comportamento.
Partindo-se desta premissa desenvolveram-se neste trabalho
modelos de ordem reduzida do motor de indução para
aplicação em estudos de controle. Os modelos apresentados
são de quinta, quarta, terceira e segunda ordens.
Para o acompanhamento completo do projeto de controle,
funções de transferência são de suma importância. As
funções de transferência, quando aplicadas aos modelos
desenvolvidos usando formulação de variáveis de estado,
permitem através de simulação digital, obter informações
de todos os pares entrada-saída que sejam necessários ao
projeto. O cálculo das funções de transferência é feito
através de dois métodos, um utilizando transformação de
variáveis e outro mantendo a formulação de variáveis de
estado. / [en]
Among the electric machines used in industrial system
presently one can highlight the induction motors, not only
for its large number but also due to the increasing
capacity of such machines.
Motors, converter and control circuits can be combined
under varied ways highlighting the necessity of an
adequate modelling for the system as a whole.
Based on information from literature the simplified model
of induction machine as a load in a power system permits
the study of its behavior with sufficient accuracy.
Starting from this concept simplified models of induction
motor were developed in this work, for apllication in the
control studies. The models showed are fifth, forth,
thirth and second order ones.
In order to follow completly the desing of control
parameters, the Transfer Function are very important. The
Transfer Functions when applied to the models developed
using state variable formulation permit through the
digital simulation obtain information of all the output-
input pairs wich are necessary for the design. The
calculation of the Tranfer Function is done based on two
methods, one using variable tranformation and the other
one maintaining the state variable formulation.
Transfer Function obtained by the two above mentioned
methods, are used to analize the control of a motor-
converter system. This control method is applied to the
rotor or stator of the machine.
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Inter-Bar Currents In Rotating Stator Induction MachinesCzarnuch, Stephen 12 1900 (has links)
This work pioneers the experimental acquisition of data relating to the heating effects of inter-bar currents and the frequency components of the main field rotating flux. Previous research in the field of inter-bar currents is reliant on theory and mathematical modeling. Yet, with the growing need for increasing machine efficiency; experimental application of conceptualized theoretical models of machine losses is paramount. Focusing specifically on inter-bar currents in a rotating stator induction machine revealed a correlation between the heat generated in the iron core and the presence of inter-bar currents. Using temperature sensing instrumentation, experimental data was gathered to determine the inter-bar current distribution along the length of the rotor bars during acceleration. Additionally, custom current transducers were implemented to directly measure the main field rotating flux. The results present a solid foundation for direct and indirect measurement of inter-bar currents. / Thesis / Master of Applied Science (MASc)
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[en] MOTOR SPEED ESTIMATION WITH SENSORLESS VECTORIAL CONTROL, EMPLOYING AN EXTENDED KALMAN FILTER WITH ESTIMATION OF THE COVARIANCE OF THE NOISES / [pt] ESTIMAÇÃO DE VELOCIDADE DO MOTOR COM CONTROLE VETORIAL SEM SENSOR, UTILIZANDO FILTRO ESTENDIDO DE KALMAN COM ESTIMAÇÃO DA COVARIÂNCIA DOS RUÍDOSJAIME ANTONIO GONZALEZ CASTELLANOS 17 November 2004 (has links)
[pt] Este trabalho apresenta uma solução para a estimação da
velocidade do motor de indução quando é aplicado um
controle vetorial sem sensor sensorless, utilizando o
filtro estendido de Kalman com um filtro secundário,
inovador, que proporciona os valores ótimos das matrizes de
covariância e pode trabalhar em forma on-line. / [en] This work presents a solution to estimate the induction
motor drive speed when a sensorless vectorial control is
applied employing an extended Kalman Filter with a
secundary filter, innovative, which supply the optimal
covariance matrix values of the noise and it permit to work
online way.
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Proposta de aplicação de motor de indução linear tubular na extração de petróleo. / A tubular linear induction motor for potroleum exploitation.Alvarenga, Bernardo Pinheiro de 11 February 2004 (has links)
O presente trabalho apresenta o desenvolvimento de um protótipo de motor de indução linear tubular para aplicação na extração de petróleo. A principal função do motor é acionar diretamente uma bomba de sucção instalada no fundo de um poço em terra. São estabelecidas as diretrizes de projeto elétrico do motor, em conjunto com uma análise preliminar baseada na teoria convencional das máquinas elétricas. Propõe-se a aplicação do método das matrizes de transmissão para obter um modelo analítico mais preciso do motor de indução linear tubular. Também é apresentado o modelo obtido pela aplicação do Método dos Elementos Finitos. Os resultados dos modelos teóricos convencional e matricial são confrontados com os resultados do modelo por Elementos Finitos e de testes, mostrando boa concordância. De maneira geral, os resultados indicam que o motor tubular pode substituir com vantagens o sistema mecânico de superfície e o conjunto de hastes utilizados na extração de petróleo. / This report presents the development of a tubular linear induction motor for oil well applications. The aim of the motor is to directly drive an on-shore downhole piston pump with no rods. Guidance to the electric and magnetic design of the motor is established. Two forms of analysis are proposed: the rotating electrical machines (conventional) based and the transmission matrix based. A model using the Finite Element Method is also described. Conventional and matricial solutions are compared to the Finite Element and tests results, showing good agreement. In a general sense, the work results show that the tubular motor may substitute the mechanical surface system and the rod string with advantage.
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Proposta de aplicação de motor de indução linear tubular na extração de petróleo. / A tubular linear induction motor for potroleum exploitation.Bernardo Pinheiro de Alvarenga 11 February 2004 (has links)
O presente trabalho apresenta o desenvolvimento de um protótipo de motor de indução linear tubular para aplicação na extração de petróleo. A principal função do motor é acionar diretamente uma bomba de sucção instalada no fundo de um poço em terra. São estabelecidas as diretrizes de projeto elétrico do motor, em conjunto com uma análise preliminar baseada na teoria convencional das máquinas elétricas. Propõe-se a aplicação do método das matrizes de transmissão para obter um modelo analítico mais preciso do motor de indução linear tubular. Também é apresentado o modelo obtido pela aplicação do Método dos Elementos Finitos. Os resultados dos modelos teóricos convencional e matricial são confrontados com os resultados do modelo por Elementos Finitos e de testes, mostrando boa concordância. De maneira geral, os resultados indicam que o motor tubular pode substituir com vantagens o sistema mecânico de superfície e o conjunto de hastes utilizados na extração de petróleo. / This report presents the development of a tubular linear induction motor for oil well applications. The aim of the motor is to directly drive an on-shore downhole piston pump with no rods. Guidance to the electric and magnetic design of the motor is established. Two forms of analysis are proposed: the rotating electrical machines (conventional) based and the transmission matrix based. A model using the Finite Element Method is also described. Conventional and matricial solutions are compared to the Finite Element and tests results, showing good agreement. In a general sense, the work results show that the tubular motor may substitute the mechanical surface system and the rod string with advantage.
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Διάγνωση σφαλμάτων λόγω δυναμικής εκκεντρότητας σε ασύγχρονη μηχανή με χρήση της μεθόδου των πεπερασμένων στοιχείωνΠερλεπές, Γεώργιος - Παναγιώτης 01 August 2014 (has links)
Στην παρούσα διπλωματική εργασία ασχοληθήκαμε με το θέμα της μελέτης και διάγνωσης σφαλμάτων λόγω δυναμικής εκκεντρότητας σε Ασύγχρονη Μηχανή. Μοντελοποιήθηκε και αναλύθηκε η λειτουργία ενός τριφασικού ασύγχρονου τετραπολικού κινητήρα κλωβού, ισχύος 4 kW με 36 αυλακώσεις στο στάτη και 28 αυλακώσεις στο δρομέα, τόσο σε υγιή κατάσταση όσο και υπό συνθήκες σφάλματος. Πιο συγκεκριμένα, με χρήση της μεθόδου των Πεπερασμένων Στοιχείων σε δύο διαστάσεις μέσω του προγράμματος Opera, προσομοιώθηκε η λειτουργία του κινητήρα μας υπό δύο διαφορετικά ποσοστά σφάλματος, για 20% και για 40% και εφαρμόστηκε η μέθοδος της “Motor Current Signature Analysis - MCSA” για τη διάγνωση του σφάλματος αυτού υπό διαφορετικά επίπεδα φορτίου. / In this paper we addressed the issue of diagnostic research due to dynamic eccentricity related faults in Induction Machines. We modeled and analyzed the function of a three-phase quadrupole induction motor with a cage rotor with 36 stator slots and 28 rotor slots, both in healthy condition and under fault conditions. More specifically, using the finite element method in two dimensions through the "Opera" software, we simulated our motor operation under our two different error rates for 20% and 40% and subsequently we used the "Motor Current Signature Analysis - MCSA" diagnostic method for the diagnosis of this error under different load levels.
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Ανάλυση και έλεγχος επαγωγικής γεννήτριας διπλής τροφοδοσίας για σύστημα ανεμογεννήτριαςΚωνσταντόπουλος, Γεώργιος 19 January 2010 (has links)
Η παρούσα εργασία πραγματεύεται την ανάλυση και τον έλεγχο της διπλά τροφοδοτούμενης επαγωγικής μηχανής (DFIG) που χρησιμοποιείται σε συστήματα ανεμογεννητριών. Στα πρώτα κεφάλαια θα αναφερθούν κάποια στοιχεία απαραίτητα για την κατανόηση του αντικειμένου και των προβλημάτων του και ακολουθεί η ενασχόληση με την επαγωγική γεννήτρια διπλής τροφοδοσίας. Αφού αναλυθεί η μηχανή εξάγονται οι εξισώσεις λειτουργίας αυτής και του μετατροπέα και, τέλος, εφαρμόζονται οι απαραίτητοι έλεγχοι για την επίτευξη της επιθυμητής συμπεριφοράς της μηχανής σε διαφορετικές συνθήκες λειτουργίας. / The present thesis is about analysis and control of a double-fed generator for wind generators.
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Ανάλυση παθητικότητας και έλεγχος ηλεκτρομηχανικών συστημάτων με εφαρμογή στην επαγωγική μηχανήΡούσσος, Παναγιώτης-Αλέξανδρος 20 October 2010 (has links)
Στην παρούσα διπλωματική εργασία εκπονείται μελέτη που αφορά την παθητικότητα και τον έλεγχο ηλεκτρομηχανικών συστημάτων. Δίνεται μεγαλύτερη βαρύτητα στον επαγωγικό κινητήρα και τους ελέγχους που μπορεί να εφαρμοστούν σε αυτόν. Η επαγωγική μηχανή χρησιμοποιείται σε μεγάλο εύρος εφαρμογών στο πεδίο μετατροπής της ηλεκτρικής ενέργειας σε μηχανικό έργο. Οι αιτίες για αυτήν την προτίμηση είναι πολλές. Μεταξύ αυτών συγκαταλέγονται το φτηνό κόστος και η εύκολη συντήρηση. Για πιο απαιτητικές εφαρμογές όμως η επαγωγική μηχανή απαιτεί πολύπλοκα συστήματα τροφοδοσίας και ελέγχου. Χρησιμοποιούνται πηγές τάσης (ή ρεύματος) βασισμένες σε τοπολογίες που περιλαμβάνουν διατάξεις με ηλεκτρονικά ισχύος όπως μετατροπείς ac/dc με IGBT διακοπτικά στοιχεία ισχύος. Ο έλεγχος επίσης μπορεί να βασίζεται είτε σε απλές βαθμωτές λογικές ή σε πιο προχωρημένα συστήματα σε λογικές διανυσματικού ελέγχου. Στις περιπτώσεις αυτές μπορούμε να επιτύχουμε εξαιρετικά λειτουργικά χαρακτηριστικά όπως ρύθμιση στροφών ή θέσης με υψηλή ακρίβεια αλλά με κόστος την πολυπλοκότητα στην δομή του συστήματος ισχύος και αυτομάτου ελέγχου. Στην παρούσα διπλωματική εργασία, αρχικά μελετάμε τη δυναμική συμπεριφορά τριφασικής ασύγχρονης μηχανής με χρήση του αναλυτικού μη γραμμικού μοντέλου της. Συγκεκριμένα, για την μελέτη της μεταβατικής συμπεριφοράς χρησιμοποιούμε το μετασχηματισμένο μοντέλο της μηχανής στο σύστημα κάθετων αξόνων d-q. Αυτό επιτυγχάνεται με την χρήση του μετασχηματισμού Park, στο τριφασικό αρχικό μοντέλο της μηχανής. Η επιλογή του συστήματος κάθετων αξόνων γίνεται στο στρεφόμενο με σύγχρονη ταχύτητα σύστημα αναφοράς. Στο σύστημα αυτό οι ημιτονοειδείς ποσότητες των μεταβλητών στην μόνιμη κατάσταση λειτουργίας μετατρέπονται σε συνεχείς (dc) μεταβλητές, πράγμα που διευκολύνει την ανάλυση και σχεδίαση του ελέγχου. Με στόχο την εφαρμογή απλών σχημάτων ελέγχου στην επαγωγική μηχανή που να μπορούν να οδηγούν σε λειτουργία υπό επιθυμητό αριθμό στροφών ανεξάρτητα προς το εμφανιζόμενο στην έξοδο μηχανικό φορτίο, χρησιμοποιούμε το μοντέλο αυτό στην ανάλυσή μας και αποδεικνύουμε ότι η επαγωγική μηχανή έχει την σημαντική ιδιότητα των Euler-Lagrange ηλεκτρομηχανικών συστημάτων, την παθητικότητα. Αυτό σημαίνει ότι μετά από κάποια διαταραχή, το σύστημά μας έχει απόσβεση τόσο στο ηλεκτρικό όσο και στο μηχανικό του μέρος. Επιπλέον, αποδεικνύεται ότι η ιδιότητα αυτή παραμένει ισχύουσα ανεξάρτητα με το όποιο σχήμα μη δυναμικού ελέγχου μπορούμε να εφαρμόσουμε. Έτσι, στην παρούσα διπλωματική εργασία εφαρμόζουμε απλούς PI ελεγκτές με σταθερά χρόνου πολύ μεγαλύτερη από αυτήν που εμφανίζει το αρχικό σύστημα, ούτως ώστε η δυναμική των PI ελεγκτών πρακτικά να μην εμπλέκεται με την δυναμική του συστήματος. Έτσι, το σύστημα παραμένει ουσιαστικά στην αρχική δυναμική του κατάσταση με την ιδιότητα της παθητικότητας ισχύουσα για τον προτεινόμενο έλεγχο που από την πλευρά της μηχανής φαίνεται πρακτικά στατικός. Εν συνεχεία, προσομοιώνουμε το σύστημα και επιβεβαιώνουμε ότι οι προτεινόμενοι απλοί PI ελεγκτές μπορούν να οδηγήσουν το σύστημα στην επιθυμητή κατάσταση λειτουργίας με επιθυμητό αριθμό στροφών. / This diploma thesis forms a study on passivity and control of electromechanical systems. We focus on induction machine and the methods we use to control it. Induction machine is used in a large range of applications especially in the field of energy conversion to mechanical work. There are many causes for this preference such as low cost and easy to preserve. For more demanding applications induction machine needs complicated supply sources and control systems. Voltage (or current) sources are used based on power electronics such as ac/dc converters with IGBT switching elements. The control used can be scalar in simple applications or vector control in advanced applications. By using vector control, we can achieve exceptional operational characteristics on velocity or position regulation with high precision but with huge complexity in the structure of the power system and the automatic control scheme. In this thesis, at first we study the dynamic performance of the 3-phase induction machine by using the precise non-linear model. Specifically. we use the transformed model of the induction machine on the dq axes system to study its dynamical performance. This can be achieved by using Park transformation on the initial 3-phase model of the machine. The choice we make on the dq axis is based on the synchronously rotating reference frame. In this system the sinusoidal quantities of the variables in steady state are converted to dc, helping us on the analysis and the design of the control. Our goal is the application of simple control shapes on the induction machine that can drive our system to the desirable velocity regardless the output of the mechanical load. To this end, in our analysis we first prove that the induction machine has the significant property of passivity, a fundamental property of Euler-Lagrange systems. This means that after a disturbance, our system has damping in both the mechanical and the electrical part. Moreover, it is proved that passivity is maintained regardless from the form of any non dynamic control scheme we may apply. So, in this thesis we use simple PI controllers with large time constant in order to avoid any influence between the dynamics of the PI controllers and the dynamic of our system. So the system maintains its initial dynamic property of passivity under the control we use. Afterwards, we simulate the system and we confirm that the PI controllers we use can drive the system to the desirable operational mode.
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