Induction-coil transducers for measuring transversal field harmonics in accelerator magnets

162 Pages·2017·30.45 MB·English

by  Eng. Caiafa Gianni

U N F II
NIVERSITY OF APLES EDERICO
D E E
EPARTMENT OF LECTRICAL NGINEERING
I T
AND NFORMATION ECHNOLOGY
PHD THESIS
IN
INFORMATION TECHNOLOGY AND ELECTRICAL ENGINEERING
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1 Induction-coil transducers for measuring
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I transversal field harmonics in
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H19 accelerator magnets
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Supervisor: Candidate:
Prof. Pasquale Arpaia Eng. Gianni Caiafa
2017-2018
©GianniCaiafa

Dedicoquestatesiamieifavolosigenitori,allaloronobiltàd’animoeallaloroonestà.
Thisthesisisdedicatedtomyfabulousparents,totheirnoblenessandtheirhonesty.

Sommario
Ilpresentelavoroditesiriguardalosviluppomatematico,lavalidazionenumerica,laproget-
tazioneelacaratterizzazionemetrologicadiuninnovativosensoreperlamisuradicampo
magneticobasatosubobinarotante.
In particolare, il modello matematico che lega le misure magnetiche al calcolo del campo
magnetico nell’apertura di magneti per acceleratori è stato validato numericamente utiliz-
zandodatiottenutidasimulazioniFEM.
Sulla base delle simulazioni numeriche è stato sviluppato il design dell’innovativo sensore
basato su bobina rotante. In particolare, data l’esigenza di eseguire misure del profilo di
campomagneticosututtalalunghezzadelmagnete,ilsensorerichiedel’assenzadisensibilità
allacomponentetrasversaledicampo. Pertalemotivolageometriadelsensoreprevedeun
determinatonumerodispirechesirichiudanopercorrendolaperiferiadiuncilindro. Tale
particolaregeometriaèstatabattezzata"Iso-perimetrica".
Avalledeldesignèstatadefinitalatecnologiacostruttivadelsensore,ildesigndeltrasdut-
toreelosviluppodinuovemetodologieperilcalcolodeicoefficientidisensitivitàeperla
calibrazionedelsensoreedeltrasduttore.
Infine, sono riportati i risultati sperimentali utilizzando il primo prototipo realizzato, lo
sviluppodelsecondoprototipoeirisultatiottenutiperunaparticolareapplicazione.
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Resume
The following thesis deals with the mathematical development, the numerical validation,
the design, and the metrological characterization of an innovative sensor for magnetic
measurementsbasedonrotatingcoils.
Thedevelopedmathematicalmodel,linkingexperimentaldataandthefielddescriptionin
theapertureofmagnetsforaccelerator,wasnumericallyvalidatedusingsimulateddata. The
validationresultsmadeitpossibletocheckthecorrelationbetweenmeasurementsandthe
mathematicalmodelitself.
Furthermore,thenumericalvalidationallowedtosatisfytheconstraintsforthedesignand
manufacturingtolerancesofthesensor.
Thesensorthatisrequiredtoperformlocalfielddistributionmeasurementsalongthemagnet
axis, mustbenot sensitive tothez-fieldcomponent (namelytothe fieldinthe directionof
beamtravellingintheparticleacceleratormagnet). Forthisreason,thecoildesignisbased
onacertainnumberofloopsplacedonthesameradius. Thisparticulargeometryhasbeen
called"Iso-perimetric".
Thesensorproduction,thetransducerdesign,aninnovativemethodologyforthesensitivity
coefficientscalculationsandforthecalibrationprocedurewerecarriedout.
Finally, theexperimentalresultsoftheproofofprincipleofthe firstprototype,thedesignof
thesecondprototype,andthemeasurementsresultsarereported.
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List of publications
JournalPapers:
[1] P.Arpaia,G.Caiafa,S.Russenschuck,ARotating-CoilMagnetometerforScanning
TransversalFieldHarmonicsinAcceleratorMagnets,NatureScientificReports,2018,
DOI:10.1038/s41598-018-37371-3.
[2] P.Arpaia,G.Caiafa,S.Russenschuck,Aflexibleprinted-circuitboardcoilforscanning,
transversal magnetic-fields errors in accelerator magnets, submitted to Sensors &
Actuators: A.Physical,2018.
[3] P.Arpaia,G.Caiafa,S.Russenschuck,Atransducerbasedonarotatingiso-perimetric
inductioncoilsensor,submittedtoTransactionsonInstrumentationandMeasurement,
2018.
ConferencePapers:
[4] P. Arpaia, G. Caiafa, S. Russenschuck, An induction rotating coil for longitudinal
scanningofparticleacceleratormagnets,JournalofPhysicsConferenceSeries,Vol.
1065,No. 17,2018,doi:10.1088/1742-6596/1065/5/052047.
[5] P.Arpaia,G.Caiafa,S.Russenschuck,AnIso-PerimetricRotating-CoilMagnetometer,
IEEESensors2018,NewDelhi,2018.
[6] S.Russenschuck,G.Caiafa,L.Fiscarelli,M.Liebsch,C.Petrone,P.Rogacki,Chal-
lengesinextractingpseudo-multipolesfrommagneticmeasurements,ICAP’18,Key
West,Florida,USA.
[7] G. Brando, A. Dannier, L. P. Di Noia and G. Caiafa, Axial flux permanent machine
design for low speed high torque application, 2017 IEEE 6th ICRERA, San Diego,
CA,2017.
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