Design and Implementation of a Real-Time System Survey Functionality for Beam Loss Monitoring Systems, Phd Thesis © 2018
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P H DTHESIS DESIGNANDIMPLEMENTATIONOF AREAL-TIMESYSTEMSURVEYFUNCTIONALITY FORBEAMLOSSMONITORINGSYSTEMS csaba f. hajdu Supervisors dr. tamás dabóczi dr. christos zamantzas Budapest University of European Organization for Technology and Economics Nuclear Research 2018 [ FINAL VERSION – August 3, 2018 at 18:27 ] Csaba F. Hajdu: Design and Implementation of a Real-Time System Survey Functionality for Beam Loss Monitoring Systems, PhD thesis © 2018 [email protected] This document was typeset using the typographical look-and-feel classicthesis developed by André Miede and Ivo Pletikosi´c.The style was inspired by Robert Bringhurst’s seminal book on typography “The Elements of Typographic Style”. classicthesis is available for both [ FINAL VERSION – August 3, 2018 at 14:30 ] LATEX and LYX: https://bitbucket.org/amiede/classicthesis/ [ FINAL VERSION – August 3, 2018 at 18:27 ] Dedicated to Gabi. Who else? Had I the heavens’ embroidered cloths, Enwrought with golden and silver light, The blue and the dim and the dark cloths Of night and light[ FINAL and VERSION the half-light,– August 3, 2018 at 14:31 ] I would spread the cloths under your feet: But I, being poor, have only my dreams; I have spread my dreams under your feet; Tread softly because you tread on my dreams. — W. B. Yeats [ FINAL VERSION – August 3, 2018 at 18:27 ] ABSTRACT This PhD thesis describes the design and implementation of a real-time system survey functionality for beam loss monitoring (BLM) systems, with a particular focus on signal processing aspects. In Part i, I introduce the basic concepts fundamental to the project. I give an overview of the European Organization for Nuclear Re- search (CERN), where the bulk of this research work was carried out. I introduce the basic principles of BLM systems, followed by details of the new BLM system under installation and commissioning tar- geted by the project. I also present a survey of the related literature, along with the first measurement and simulation results related to the identification of the BLM system. The switching operation of the high voltage power supplies results in a parasitic signal in the acquisition chain of the new beam loss monitoring system. Part ii presents a modification of the adaptive Fourier analyzer aimed at detecting these spurious components, with a view to realizing a noninvasive system survey. I introduce a novel frequency adaptation method, universally usable for resource-efficient frequency adaptation in a Fourier analyzer. Part iii presents another approach to surveying the new BLM sys- tem, relying on an external excitation applied to the detectors. The current best method and the suggested new solution are described, the latter complemented by implementational considerations and some operational experience. Part iv introduces methods intended to aid detecting the presence of an arbitrary predefined pattern repeated periodically in a digitized data stream. I present several novel modifications to the Fourier ana- lyzer facilitating pattern detection, with some also making it possible to detect additive disturbances in the frequency bands covered by the pattern. I show how a modified Fourier analyzer can be used to real- ize a lightweight time-variant cross-correlation filter, which produces the peak cross-correlation value in every time step when properly synchronized to the input signal. All the structures I present need to be synchronized to the input signal, for which I also introduce two algorithms. iv [ FINAL VERSION – August 3, 2018 at 18:27 ] KIVONAT Ez a PhD értekezés egy valós idej˝urendszerfelügyeleti eljárás meg- tervezését és megvalósítását mutatja be nyalábveszteség-monitorozó (BLM) rendszerekhez, különös figyelmet szentelve a jelfeldolgozási vonatkozásoknak. Az i. részben bevezetem a projekthez kapcsolódó alapvet˝ofogalma- kat. Áttekintést nyújtok az Európai Nukleáris Kutatási Szervezetr˝ol (CERN), ahol a kutatás nagy részét elvégeztem. Bemutatom a BLM rendszerek alapelveit, majd részletesebben leírom azt a jelenleg is telepítés és üzembe helyezés alatt álló új BLM rendszert, amellyel pro- jektem során foglalkoztam. Áttekintem a kapcsolódó szakirodalmat, valamint bemutatom a BLM rendszer identifikációjához kapcsolódó kezdeti mérési és szimulációs eredményeimet. A nagyfeszültség˝utápegységek kapcsolóüzeme parazita jelkom- ponenseket hoz létre az új nyalábveszteség-monitorozó rendszer jel- átviteli láncában. A ii. rész az adaptív Fourier-analizátor egy olyan módosítását mutatja be, amelynek célja ezen zavaró jelkomponen- sek detektálása a rendszerfelügyelet neminvazív megvalósítása ér- dekében. Egy új frekvencia-adaptációs eljárást javaslok, amely uni- verzálisan használható a frekvencia er˝oforráshatékonyadaptálására Fourier-analizátorokban. A iii. rész egy másik megközelítést mutat be az új BLM rendszer felügyeletére, amely a detektorokra alkalmazott küls˝ogerjesztésre támaszkodik. Részletezem a jelenlegi legjobb módszert és a javasolt új megoldást, ez utóbbihoz implementációs szempontokat és az üzemel- tetés során szerzett tapasztalatokat is f˝uzve. A iv. rész olyan módszereket mutat be, amelyek célja egy digitális adatfolyamban periodikusan ismétl˝od˝otetsz˝oleges,el˝ore definiált min- tázat jelenléte detektálásának el˝osegítése.Több új, a minta detektálását megkönnyít˝omódosítást javaslok a Fourier-analizátorhoz, amelyek közül néhány a mintázat által lefedett frekvenciasávokban megjelen˝o additív zavarjelek detektálását is lehet˝ové teszi. Megmutatom, hogyan lehet egy módosított Fourier-analizátorral id˝ovariáns keresztkorreláci- ós sz˝ur˝otmegvalósítani, amely helyes szinkronizáció esetén minden id˝olépésbena keresztkorrelációs függvény maximumát állítja el˝o.Az összes bemutatott struktúrát szinkronizálni szükséges a bemen˝ojelhez, amelyre szintén javaslok két algoritmust. v [ FINAL VERSION – August 3, 2018 at 18:27 ] ACKNOWLEDGMENTS The present thesis is the culminating point of a long and adventurous journey. Many people have contributed to it at different times and in different ways – those named in the following are but a few of them. I would like to start with the late Bernd Dehning, to whom I will be forever grateful. Without his instinct and confidence in me, I would probably never have ended up in the Beam Loss section at CERN in the first place. Bernd extended a welcoming hand to me when the time had come for me to return to BL to embark on this thesis, and gave me many useful hints along the way. This thesis could never have been written without the guidance of Tamás Dabóczi and Christos Zamantzas. Tamás first became my supervisor during my bachelor studies at Budapest University of Technology and Economics, and his guidance and suggestions as PhD thesis supervisor in matters both technical and administrative have been invaluable in shaping this work into what it has become. Christos was my supervisor for the whole of the time I spent with the Beam Loss section at CERN. Early on, he helped me a lot in getting integrated and picking up what I needed to know about accelerator physics. He made it possible for me to attend many courses and conferences. All along the way, he trusted me fully, let me shape my work in a way that suited me, and was always ready to listen to me and give me counsel whenever I needed it. Both Tamás and Christos have played important roles in my becoming the person I am today, and they have my eternal gratitude. I am also thankful to Gábor Péceli, Tadeusz Dobrowiecki and László Sujbert for the effort they put into reviewing my manuscripts and for their great proposals to improve them. My colleagues at CERN also played a part, both professionally and personally. Many thanks to William Viganò for creating a particular, yet very enjoyable atmosphere in the office, for all the time and energy he invested into solving the problems related to the project I turned to him with, and for helping me ‘defeat the shyness’ along with Jonathan Emery, Eleftherios Fadakis, Zsolt Sz˝okeand Roger Barlow. Thanks to Ewald Effinger for always being available to answer my questions and for countless lunch break runs with David Woog. I am also grateful for a very pleasant workplace atmosphere and lots of common coffee breaks to everyone I shared my time in the BL section with, including Andreas Alexopoulos, Slava Grishin, Kristian Hjorth, Maria Kastriotou, Örs Málnási-Csizmadia, Eduardo Nebot Del Busto, Roberto Rocca, Ion Savu, Christiane Schillinger, Volker Schramm, Luca Timeo, Raymond Tissier and Benedikt Würkner. vi [ FINAL VERSION – August 3, 2018 at 18:27 ] When it was time for me to return to the Department of Measure- ment and Information Systems to continue working on this thesis, I also got a very warm welcome. Thanks to András Széll for many ideas for side projects; Béla Fehér, Gábor Hullám, Gábor Naszály, Tamás Kovácsházy, Balázs Scherer, Péter Szántó and Gábor Wacha for many inspiring lunch breaks together; to Balázs Bank and György Orosz for their help with my teaching duties; to Dániel Hadházi and Péter Nagy for good company in the office. My warmest thanks to my friends at CERN I shared many lunch breaks and even more adventures with. I will not forget our many dinners and drinks together in the city, ski and snowboard outings, hikes with or without snowshoes, wine tastings and so much more: Márton Ady, Patrick Alknes, Cyndi Araujo, Ole-Kristian Berge, Nicola Black, Jorge Flores Vega, Ben Frisch, Daniel Gomez Blanco, Simon Heck, Julian Kadar, Aurélien Marsili, Bálint Radics, Alejandro Sanz Ull, Monika Sitko, Flavia Sperati, Gen Steele, Ágnes Szeberényi