Transcript CLIC_Prjt_Meeting_24_May_2013_DAx

DB Klystron Modulators R&D Status
Dr. Davide Aguglia, TE/EPC
CLIC Project Meeting #12, CERN
24th May 2013
• Work Package description & Specifications
• R&D strategy and collaborations
• Solutions under study
• Ongoing work
• Preliminary results / Issues
• Published results
• Planning
• Conclusion
WP description and specifications
~1600 klystron Modulators required here
Modulator main specifications
Pulse voltage
Vkn
150
kV
Pulse current
Ikn
160
A
Peak power
Pout
24
MW
Rise & fall times
trise
3
μs
Flat-top lenght
tflat
140
μs
Repetition rate
Repr
50
Hz
Flat-top stability
FTS
0.85
%
Pulse repeatability
PPR
10-50
ppm
•Goal: 2 full scale DB CLIC klystron
modulators prototypes in 2016
Voltage [V]
•High efficiency
•High reliability / availability
Vovs
Vkn
FTS
•CERN + External collaborations
- ETH Zurich, CH
- University of Nottingham, UK
- LAVAL University, Canada
real pulse
ideal pulse
treset
trise tset
tfall
tflat
Vuns
Time [s]
Trep
DB klystron modulators R&D status
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R&D strategy and collaborations
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1.
2.
3.
General concept
At CERN we study common issues
to all R&D partners
Tasks allocation considering partner
expertise
Obtain 2 topologically different
solutions (VAC not defined)
ETHZ
LAVAL
Full modulator delivery
Low voltage primary solution
Split-core transformer
Parallel redundancy
PFS Delivery
High voltage primary solution
Monolithic transformer
Series redundancy
Klystron modulator
Low voltage
configuration
HV
MV
ESS?
(smes?)
LV
Charger
PFS
m=1
Charger
PFS
m=n-1
Charger
PFS
m=n
Charger
PFS
m=1
PFS
m=1
PFS
m=n-1
ESS?
(flywleel?)
LV
CERN
common interest issues
Voltage repeatability
High precision measurements
Reliability / Availability
High voltage
configuration
HV
MV
MV
AFE
(MMC)
m=n
PFS
ESS?
HVDC
lines
SVC?
MV
AFE
(MMC)
High BW /
step-up
DC/DC
PFS
Nottingham
Charger & Grid concept
High or low voltage solution?
Optimal grid and charger
layout proposal
DB klystron modulators R&D status
SLAC
?????????????????
Transformer-less solution
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Solutions under study

Basic principles and power fluctuation problematic
of klystron modulators
One slowly charges a
capacitor bank at low
power and discharge it
at high power when
pulse needed.
Power fluctuation
problematic
DB klystron modulators R&D status
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Solutions under study
New topologies under study

ETHZ Special spec- Consideration of a DC voltage<
4kV; parallel modularity
Split core
transformer
1. Allows parallel redundancy.
2. use of standard LV switches.
3. Fast voltage rise-time
4. Natural voltage balancing
Modular
charger

Active
bouncer
Active
bouncer
Active
bouncer

LAVAL Special spec- Consideration of a DC voltage>
4kV; series modularity
Monolithic
transformer
Monolithic
transformer
Active
bouncer
Active
bouncer
DB klystron modulators R&D status
1. 2-purpose active
bouncer: pulsed voltage
regulation & constant power
consumption
2. Alleviates charger’s spec.
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Ongoing work
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ETHZ: 1. Construction of full-scale split-cores HV
pulse transformer prototype, 2. Design of
multiphase active bouncer.
Uni Nottingham: 1. Evaluation of candidate charger
topologies, 2. Optimisation of Grid-layout for CLIC.
LAVAL Uni: 1. HV insulating materials studies (with
measurements) 2. HV pulse transformer
optimisation, 3. 2-purpuse active bouncer small
scale prototype construction.
CERN: 1. Power converters repeatability prediction
and measurements techniques 2. High precision
and repeatable HV measurement systems.
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Preliminary results / Issues

Output voltage pulse feasibility
•

Promising topologies
•

With the 2 proposed topologies, it seems possible, by numerical
simulation, to obtain the required output pulse.
The 2 topologies (ETHZ - LAVAL) are very promising. Not possible
to argue which is best yet.
Prediction on meeting specifications
•
•
•
•
Pulse shape: Seems possible to meet.
AC power fluctuation: Depends to which extent…specs on 400kV
lines under definition! Seems possible to achieve 5% of power
fluctuation “easily”.
Pulse to Pulse repeatability: very challenging – Impact on cost if
10ppm - strong collaboration with RF needed.
Electrical efficiency: Probably achievable with a centralised chargers
(4 @ 75MW each)…to early to answer.
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Published results
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17 papers (journal and conferences) on novel modulators
topologies and design methods
D. Aguglia, P. Viarouge, C. A. Martins, “Frequency-Domain Maximum Likelihood Estimation of High-Voltage
Pulse Transformers Models Parameters”, IEEE Transactions on Industry Applications, 2013.
Candolfi, S., D. Aguglia, P. Viarouge, J. Cros, “Efficient parameter identification method for high voltage pulse
transformers”, IEEE pulsed power and plasma science conference (PPPS), San Francisco, USA, June 2013.
Candolfi, S., P. Viarouge, D. Aguglia, J. Cros, “Finite elements based optimal design approach for high
voltage pulse transformers”, IEEE pulsed power (PPPS), San Francisco, USA, June 2013.
M. Jancovic, A. Watson, J. Clare, P. Wheeler, D. Aguglia, “Grid interface challenges and candidate solutions
for the Compact linear collider’s (CLIC) klystron modulators”, IEEE pulsed power (PPPS), San Francisco,
USA, June 2013.
F. C. Magallanes, D. Aguglia, P. Viarouge, C. A. Martins, J. Cros, “A novel active bouncer system for klystron
modulators with constant AC power consumption”, IEEE pulsed power (PPPS), San Francisco, USA, June
2013.
S. Blume, J. Biela, “Optimal Design Procedure of an Active Bouncer for an Ultra Precise Long Pulse Solid
State Modulator”, ”, IEEE pulsed power (PPPS), San Francisco, USA, June 2013.
K. Papastergiou, D. Aguglia, “Power system design compromises for large-Scale linear particle accelerators”,
European Power Electronics Conference (EPE), Lille, France, September 2013.
D. Aguglia, M. Neuhaus, “Laminated magnetic materials losses analysis under Non-Sinusoidal Flux
Waveforms in Power Electronics Systems”, the European Power Electronics Conference (EPE), Lille, France,
September 2013.
DB klystron modulators R&D status
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Published results
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D. Aguglia, “Pulse Transformers Design for Magnets Powering in Particles Accelerators”, European Power
Electronics Conference (EPE), Lille, France, September 2013.
S. Blume D. Gerber J. Biela, Optimal Transformer Design for an Ultra Precise Long Pulse Solid State
Modulator, Proceedings of the 4th Euro-Asian Pulsed Power Conference (EAPPC), Karlsruhe, Germany,
Sept. 30. - Oct. 4., 2012.
F. C. Magallanes, D. Aguglia, C. A. Martins, P. Viarouge, “Active damping filter for high bandwidth – low
ripple pulsed converters”, 15th International Power Electronics and Motion ontrol Conference, EPE-PEMC,
Novi Sad, Serbia, 2012, pp. 1 – 7.
F. C. Magallanes, D. Aguglia, C. A. Martins, P. Viarouge, “Review of design solutions for high performance
pulsed power converters”, 15th International Power Electronics and Motion ontrol Conference, EPE-PEMC,
Novi Sad, Serbia, 2012, pp. 1 – 6.
D. Aguglia, E. Sklavounou, “ Klystron modulators capacitor chargers design compromises for AC power
quality increase of the compact linear collider”, SPEEDAM, Sorrento (IT), 2012, pp. 1 – 7.
R. H. Soares, D. Aguglia, “Pulse-to-pulse reproducibility efficient prediction method for high precision klystron
modulator design”, in Proc. IEEE IPMHVC, San Diego (CA), USA, 2012, pp. 1 – 4.
D. Aguglia, P. Viarouge, C. A. Martins, “Frequency domain non-linear identification method for high voltage
pulse transformers”, in Proc. International conference on Electrical Machines (ICEM), Marseille, France,
2012, pp. 1 – 7.
P. Viarouge, D. Aguglia, C. A. Martins, J. Cros, “Modeling and dimensioning of high voltage pulse
transformers for klystron modulators”, in Proc. International conference on Electrical Machines (ICEM),
Marseille, France, 2012, pp. 1 – 7.
D. Aguglia, C. de Almeida Martins, M. Cerqueira Bastos, D. Nisbet, D. Siemaszko, E. Sklavounou, P.
Viarouge, “Klystron Modulator Technology Challenges for the Compact Linear Collider (CLIC), In Proc., IEEE
International Conference on Pulsed Power, Chicago, 2011.
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Planning
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Planning & collaborations
ETHZ
2013
2014
2015
2016
Transfo. Design
tool +validation &
active bouncer
Charger studies +
validation &
component order
for full scale
Mod 1 assembly
& tests + control
optimisation
Mod 1 delivered
to CERN
LAVAL
Nottingham
CERN (3 Fell)
Transfo. Design
Modular multilevel
Repeatability &
tool + Validation &
Converter
reliability studies
novel active
capabilities study +
+ validation /
bouncer design +
validation
statistical mes.
small scale
Continuation &
validation
input to
Topology
selection
Components order
collaborations
&
Grid
layout
& assembly of
optimisation
transfo. + active
bouncer
Decision on charger for Mod 2
Standard (industrial) or
Assembly of PFS
Nottingham charger construction
at CERN
Mod 2 delivered
to CERN
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Conclusion
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Work Package mainly keeps the original objectives.
Specifications are very hard to be met – in 2016
there will be 2 modulators respecting at least the
pulse shape and stability. We do the maximum to
reach the highest repeatability, efficiency, reliability
and minimum AC power fluctuation.
A collaborative approach with RF must be adopted
regarding repeatability issues.
We are on schedule (for the moment at least).
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