Induction Heating Converter's Design, Control and Modeling Applied To

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Induction Heating Converter's Design, Control and Modeling Applied To i \PhD" | 2012/5/21 | 8:58 | page 1 | #1 i i i Universitat Politecnica` de Catalunya Departament d'Enginyeria Electrica` Doctoral Thesis Induction heating converter's design, control and modeling applied to continuous wire heating Autor: Guillermo Mart´ınSegura Director: Daniel Montesinos i Miracle Barcelona, June 2012 i i i i Universitat Polit`ecnicade Catalunya Departament d'Enginyeria El`ectrica Centre d'Innovaci´oTecnol`ogicaen Convertidors Est`aticsi Accionament Av. Diagonal, 647. Pl. 2 08028 Barcelona Copyright c Guillermo Mart´ınSegura, 2012 Impr`esa Barcelona Primera impressi´o,Juny 2012 ISBN:- i \PhD" | 2012/5/21 | 8:58 | page 3 | #2 i i i Acta de qualificació de tesi doctoral Curs acadèmic: Nom i cognoms DNI / NIE / Passaport Programa de doctorat Unitat estructural responsable del programa Resolució del Tribunal Reunit el Tribunal designat a l'efecte, el doctorand / la doctoranda exposa el tema de la seva tesi doctoral titulada __________________________________________________________________________________________ _________________________________________________________________________________________. Acabada la lectura i després de donar resposta a les qüestions formulades pels membres titulars del tribunal, aquest atorga la qualificació: APTA/E NO APTA/E (Nom, cognoms i signatura) (Nom, cognoms i signatura) President/a Secretari/ària (Nom, cognoms i signatura) (Nom, cognoms i signatura) (Nom, cognoms i signatura) Vocal Vocal Vocal ______________________, _______ d'/de __________________ de _______________ El resultat de l’escrutini dels vots emesos pels membres titulars del tribunal, efectuat per l’Oficina de Doctorat, a instància de la Comissió de Doctorat de la UPC, atorga la MENCIÓ CUM LAUDE: SI NO (Nom, cognoms i signatura) (Nom, cognoms i signatura) (Nom, cognoms i signatura) Vicerectora de Recerca Cap de l'Oficina de Doctorat Secretari/ària del tribunal Presidenta de la Comissió de Doctorat Secretària de la Comissió de Doctorat (o membre del tribunal de la UPC) Barcelona, _______ d'/de __________________ de _______________ Diligència "Internacional del títol de doctor o doctora" Com a secretari/ària del tribunal faig constar que la tesi s'ha defensat en part, i com a mínim pel que fa al resum i les conclusions, en una de les llengües habituals per a la comunicació científica en el seu camp de coneixement i diferent de les que són oficials a Espanya. Aquesta norma no s’aplica si l’estada, els informes i els experts externs provenen d’un país de parla hispana. (Nom, cognoms i signatura) Secretari/ària del tribunal i i i i i \PhD" | 2012/5/21 | 8:58 | page i | #3 i i i Esta tesis no se podr´ıa haber realizado sin la colaboraci´ondesinteresada de muchas personas que me han brindado su ayuda, sus conocimientos y su apoyo a lo largo de estos a~nos.Aunque me sea imposible nombrarles a todos, quisiera agradecerles todo cuanto han hecho por m´ı. En primer lugar quisiera agradecerle el apoyo prestado a mi director Daniel Montesinos y a Toni Sudri`a.Por supuesto tambi´ena todos mis compa~neros de trabajo, m´asbien amigos, de los que he aprendido muchas de las cosas que hay aqu´ıplasmadas y con los que aun sigo aprendiendo y divirti´endome cada d´ıa. Tambi´enquerr´ıaagradecer muy especialmente a aquellos ex compa~neros de trabajo con los que pas´einterminables horas delante de estos armarios de calentamiento por inducci´on,intentando que aquello funcionara. Al final parece ser que funcion´o.Es imposible nombrarlos a todos, pero en especial quiero agradecer a Coia por su grata compa~n´ıadurante estos a~nos,aunque siempre me tocase cargar con las cosas y destornillar en los sitios m´asinac- cesibles. A Quim, que no deja de sorprenderme y del que a´un no dejo de aprender cosas. Y a Miquel, por su humor y por todas las cosas que me ha ense~nadodurante estos a~nos. Agradecer a mis amigos de toda la vida por ayudarme a airearme y a re´ır cuando lo necesitaba, sin eso, dif´ıcilmente hubiese continuado. No puedo dejarme a mi familia. A mi abuelo, del que aprend´ıla impor- tancia de educar a los hijos y lo poco que s´ede arreglar bicicletas, quiz´as de sus inventillos venga mi vena ingenieril. A mi abuela, de la que aprend´ı la bondad y la generosidad de aquellos que menos tienen, adem´asde al- gunos guisos memorables. A mi abuelito, del que aprend´ıla importancia de leer todo cuanto pueda, y sin el que probablemente no hubiese llegado aqu´ı. A´unrecuerdo aquel maldito examen de castellano con el que me martiriz´o durante un semestre a base de dictados y a partir del cual empec´ea sacar buenas notas. Aunque no haya podido demostrarlo a lo largo de esta tesis, aprend´ıque albahaca efectivamente se escrib´ıacon H. A mi abuelita, de la que supongo he heredado la cabezoner´ıay perseverancia que tanto me han ayudado estos ´ultimosa~nos,y de la que a´unno dejo de aprender las artes culinarias m´asselectas. A mi madre, de la que hered´ela inquietud por la ciencia y el saber, y sin la que probablemente jam´ashubiese llegado hasta aqu´ı. A mi padre, por ense~narmemuch´ısimascosas, entre ellas a tener cu- riosidad por las cosas, no s´olopor los convertidores. Tambi´enpor ense~narme i i i i i lo que es la ´eticay los principios a los que uno no debe nunca renunciar. A mi hermano, por ense~narmeque existen muchas cosas m´asall´ade la inge- nier´ıay que muchas veces son menospreciadas. En definitiva a todos, por educarme, ense~narmey apoyarme en todos los sentidos desde que empec´e con esto. Y ya por ´ultimo,a la persona sin la que indiscutiblemente esto no hubiese podido ser y que merecer´ıa el t´ıtulo honor´ıfico de coautora. A mi novia Olatz, no s´olopor su apoyo incondicional y por aguantarme, por lo que ya merecer´ıaun premio, sino tambi´enpor los millones de folios que se ha tenido que leer a medida que iba haciendo y por todo lo que me ha ayudado en la redacci´onde la memoria. Realmente esto no hubiese quedado as´ıde no ser por ella. En fin, a todos ellos: muchas gracias! Esta tesis es para vosotros. ii i \PhD" | 2012/5/21 | 8:58 | page iii | #4 i i i Acknowledgements I would like to thank all the people from the scientific community who shared with me their expertise and research insight generously and unselfishly. It is surprisingly gratifying to find that, still, one can find people who share their knowledge and spend their time with beginners. I have to admit that they helped to revive my faith in human beings. I would like to thank specially Dr. Andras Kelemen and Dr. Valentin Nemkov for their interest and for their thoughtful advises and experience that served me during this thesis. To Dr. Mircea Chindris, Dr. Ioan Vadan and the Department of Electrical Machines from the Technical University of Cluj-Napoca for their interest and support of this work. I would like to thank all the researchers that helped me during my PhD, spending their time answering simple questions from an unknown PhD student from another part of the world. It is impossible to write all the names, but some of them were Szelitzky Tibor, Dr. Nimrod Kutasi, Dr. Virgiliu Fireteanu, Dr. Valery Rudnev or Dr. Xavier Bohigas. The author would also like to thank AUTOMAT Industrial S.L for their support to this work during all this years. This work has been supported by the University and Research Commis- sioner of the Innovation, Universities and Enterprises Department of the Catalan Government and the European Social Fund. iii i i i i iv i \PhD" | 2012/5/21 | 8:58 | page v | #5 i i i Resumen El calentamiento por inducci´ones un m´etodo de calentamiento para ma- teriales conductores que aprovecha el calor generado por las corrientes de Foucault, generadas a su vez a partir de un campo magn´eticovariable. Des- de que en 1831 Michael Faraday descubri´ola inducci´onelectromagn´etica, este fen´omeno ha sido ampliamente estudiado en diversas aplicaciones como por ejemplo transformadores, motores o generadores. A principios del siglo XX la inducci´onempez´oa investigarse como un m´etodo de calentamiento, hecho que condujo en 1927 a la construcci´onpor parte de la Electric Furna- ce Company del primer equipo industrial de fusi´onpor inducci´on.As´ımis- mo, Midvale Steel y Ohio Crankshaft Company crearon el primer equipo de endurecimiento de acero con calentamiento por inducci´onen la misma ´epoca [1,2]. A´uny as´ı,no fue hasta la II Guerra Mundial, cuando el calenta- miento por inducci´onexperiment´oun gran aumento, debido a su utilizaci´on en la producci´onde proyectiles y piezas para veh´ıculos. Al principio, los campos magn´eticosnecesarios para generar el calor se ob- ten´ıancon generadores de chispas, generadores de v´alvulaso grupos motor- generador. Con la aparici´onde semiconductores comerciales en los a~nosse- senta, estos sistemas fueron poco a poco remplazados por generadores que empleaban este tipo de dispositivos. Actualmente, la mayor´ıade convertido- res de calentamiento por inducci´onemplean dispositivos semiconductores, utilizando la mayor´ıaIGBTs y MOSFETs en aplicaciones de alta frecuencia y media-alta potencia. En lo que se refiere a la caracterizaci´ondel sistema pieza-inductor, los pri- meros modelos utilizados para entender su comportamiento se basaban en m´etodos anal´ıticos.Estos modelos resultaban ´utilespara analizar la tenden- cia general del sistema, pero no eran suficientemente precisos para an´alisis m´asrigurosos y adem´asse limitaban a geometr´ıassimples. Con la aparici´on de los ordenadores, los m´etodos num´ericos experimentaron un gran creci- miento en los a~nosnoventa y se empezaron a utilizar en el campo del calen- tamiento por inducci´on.Actualmente, el desarrollo de softwares comerciales que permiten este tipo de an´alisisha propiciado su uso por parte de cen- tros de investigaci´ony empresas.
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