Performance of magnetostrictive element at LHe environment12th International Conference MIXDES 2005
Performance ofmagnetostrictive element
at LHe environment
M.Grecki, P. Sekalski Department of Microelectronics and Computer Science
Technical University of Lodz, Poland
C.Albrecht Deutsches Elektronen-Synchrotron
Hamburg, Germany
Performance of magnetostrictive element at LHe environment12th International Conference MIXDES 2005
Outline
• Motivation of experiment,
• Magnetostrictive tuner specification,
• Experiment description,
• Plans for future,
Performance of magnetostrictive element at LHe environment12th International Conference MIXDES 2005
Motivation for experiment
The change of the resonant frequency of the cavity,
The master oscillator frequency is constant.
The cavities are pulsed at high field.
The electromagnetic field interacts with cavity walls
The cavity changes its dimensions
De-tuned cavity
,
T
T
De-tuned cavity
(Lorentz force)
De-tuned cavity
BEAM PULSE ONBEAM PULSE ON
Magnetostrictive elements:• might have a higher lifetime, • are immune to shortcuts,• generate less heat,
Magnetostriction of different materials in function of temperature
(courtesy of ENERGEN).
Performance of magnetostrictive element at LHe environment12th International Conference MIXDES 2005
Magnetostrictive tuner specifications
5 x 1010 CyclesLifetime:
1.6 msPulse Length:
< 0.1 WHeat Load to 2.1 K:
60 per secondRepetition Rate:
< 25mG at 30 mm from actuatorStray magnetic field:
3 kNLoad:
2.1 KOperating Temp:
0.15 µm/ µsecSlew rate:
better than 0.2 µmResolution:
20 µm (preload 1500N)Stroke:
Dimensions:
Specification Parameter
61.8 mm High x 50 mm Wide x 22 mm Deep
5 x 1010 CyclesLifetime:
1.6 msPulse Length:
< 0.1 WHeat Load to 2.1 K:
60 per secondRepetition Rate:
< 25mG at 30 mm from actuatorStray magnetic field:
3 kNLoad:
2.1 KOperating Temp:
0.15 µm/ µsecSlew rate:
better than 0.2 µmResolution:
20 µm (preload 1500N)Stroke:
Dimensions:
Specification Parameter
61.8 mm High x 50 mm Wide x 22 mm Deep
KELVIN ALL®
0
500
1000
1500
2000
2500
3000
0 20 40 60 80 100 120 140 160
magnetic field (H) [Am-1]
mag
net
ost
rict
ion
(p
pm
)
4.2K77K293K
22 mm50 mm
61.8
mm
Performance of magnetostrictive element at LHe environment12th International Conference MIXDES 2005
Magnetostrictive tuner prototype
Plunger & Belleville springs
Active magnetostrictive element with ferrite, s.c. coil and thermal
connectors
Niobium Cover
Magnetostrictive rod(made of Kelvin ALL®)
Build by ENERGEN Inc.
Ferrite necessary to close magnetic circuit
Superconducting coil (Nb3Sn)
Thermal connectors
Performance of magnetostrictive element at LHe environment12th International Conference MIXDES 2005
Magnetostrictive tuner experimentExperiment goals• Run tuner at low temperature,• Transfer function from magnetostrictive
element to piezoelectric one • Transfer function from piezoelectric
element to magnetostrictive one• Characterize magnetostrictive tuner
vs. NOLIAC piezo stack (similar experiment with two piezostacks was
done)
- stroke vs applied current- maximal frequency
• Heat dissipation (temperature rise)
Performance of magnetostrictive element at LHe environment12th International Conference MIXDES 2005
Power Transconductance Amplifier
Technical Specifications:
• Maximum output current amplitude – 8 A
• Maximum pulse duration – 2.3 ms
• Maximum repetition frequency – 20 Hz
• Amplification – 3.33 A/V
Schematic of amplifier (designed by G. Jablonski, DMCS-TUL)
PTA based on PA93 APEX
Power Operational Amplifier
PWM amplifier is under investigation
Performance of magnetostrictive element at LHe environment12th International Conference MIXDES 2005
Magnetostrictive tuner experiment
0
0,5
1
1,5
2
2,5
3
3,5
4
4,5
0 2 4 6 8
input current [A]
ou
tpu
t vo
ltag
e [V
]
0
1
2
3
4
5
6
7
8
9
0 1 2 3 4 5 6 7 8
input current [A]
dis
pla
cem
nt
[um
]
mesurement (constant voltage/load factor)
data from Energen
mesurement (variable voltage/load factor)
Peak Piezo Voltage vs. Applied Load
0
5
10
15
20
25
30
35
0 50 100 150 200Applied Load [kg]
Pe
ak
Pie
zo V
olt
ag
e [
V]
Room T
T = 7 - 16 K
The data obtained by Energen „is” done for
preload of 400N. (no measurement for
preload was performed at LHe
temperature)
Measured data Calibration data from INFN
~2μm of displacement for 8A
Performance of magnetostrictive element at LHe environment12th International Conference MIXDES 2005
Magnetostrictive tuner - future test
• Two new magnetostrictive rods from EXTREMA are ordered. They are made of GalFeNOL.
• We would like to perform a characterization of all 3 rods (or more if possible) similar to the piezo one, including:– Displacement measurement versus magnetic field applied to device for
different preload settings (i.e. 0N, 1kN, 2kN, 3kN),
– Max. stroke,
– Dynamics of motion,
– Heat generation – coil is made of Nb3Sn,
– Magnetic field distribution (if possible)
Performance of magnetostrictive element at LHe environment12th International Conference MIXDES 2005
50 mm
62 mm
Flange for high current wires
(up to 16 Amps) Flange for temperature and magnetic field sensors wires
Interface need to be designed
Displacement sensor
Magnetic field sensors
Magnetostrictive rod inside superconducting coil
Membrane
Screw for preload force adjustment
Temperature sensors(its positions are under
investigation )
Magnetostrictive tuner - future test
Performance of magnetostrictive element at LHe environment12th International Conference MIXDES 2005
Conclusions
The maximal displacement of magnetostrictive tuner was less than 2um. The data might be not exact, because the preload force and boundary condition
were not well controlled (It might happen that the preload force was higher than 1kN, because stiffness of fixture was unknown at low temperature).
Small delay between input and output signal might be observed (around 70us). In principle it might be explained by the magnetostrictive element hysteresis
(as it is observed in RT temperature).
Finally, performed experiment does not give the quantify results, but the main goal of test was reached: the tuner was run successfully at LHe temperature.
On the other hand, the detailed magnetostrictive rod characterization is strongly required. Using the obtained experiences, the proper experiment will be prepared
and performed soon.
Performance of magnetostrictive element at LHe environment12th International Conference MIXDES 2005
References
[1] “TESLA Technical Design Report”, DESY 2001-011, 2001
[2] T. Schilcher, “Vector Sum Control of Pulsed Accelerating Field in Lorentz Force Detuned Superconducting Cavities“, PhD thesis
[4] S.N. Simrock, “Lorentz Force Compensation of Pulsed SRF Cavities”, Proceedings of LINAC 2002, Gyeongju, Korea
[5] M. Liepe, W.D.-Moeller, S.N. Simrock, “Dynamic Lorentz Force Compensation with a Fast Piezoelectric Tuner”, Proceedings of the 2001 Particle Accelerator Conference, Chicago
[6] L. Lilje, S. Simrock, D. Kostin, M. Fouaidy, “Characteristics of a fast Piezo-Tuning Mechanism for Superconducting Cavities”, Proceedings of EPAC 2002, Paris, France.
[7] P. Sekalski, S. Simrock, L. Lilje, C. Albrecht, “Lorentz Force Detuning Compensation System for Accelerating Field Gradients up to 35 MV/m for Superconducting XFEL and TESLA Nine-Cell Cavities”, MIXDES 2004, Poland
[8] Magnetostrictive tuner datasheet, ENERGEN, INC
Performance of magnetostrictive element at LHe environment12th International Conference MIXDES 2005
Thank you for your attention
Top Related