REGULATION LOOPS AND RF CONTROL SYSTEM FOR SOLEIL

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REGULATION LOOPS AND RF CONTROL SYSTEM FOR SOLEIL
8th ESLS RF meeting Daresbury, September 29th -
30th, 2004
M. DIOP
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BOOSTER 35 KW AMPLIFIER
2.5 kW ampli
8-way splitter
2.5kW coupler
8 x 330 W
2-way splitter
2x20 kW combiner
35 kW
40 kW coupler
35 kW AMPLIFIER
20 kW
(18 x 8) 2 146 modules
146 modules of 330 W
2.5 kW ampli
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AMPLIFIER SUPERVISION

• Microcontroller and multiplexing system

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BOOSTER REGULATION LOOPS

• 3  slow  loops (frequency, amplitude and phase)
• Adapted version of the LURE system

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REGULATION LOOPS

• Characterization of the regulation loops

Frequency loop transfer function
Voltage loop transfer function
Result BP 10 kHz for a 200 mV modulation
Result BP 5 Hz for a 50 mV modulation
P 10 KW
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BOOSTER CONTROL SYSTEM
LLES Low Level Electronic systems
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STORAGE RING AMPLIFIER

• 190 kW Amplifier (1 per cavity)

4 x 50 kW 726 modules of 315 W
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50 KW UNIT PRINCIPLE
2-way splitter
10-way splitter
50 kW UNIT
x 4 for one 190 kW ampli 4 x 10 (20 x 8) 2
682 44  stand-in  726 modules
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AMPLIFIER SUPERVISION

• Microcontroller and multiplexing system

STORAGE RING AMPLIFIER CONTROL
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ROBINSON STABILITY

• STORAGE RING 4 Superconducting 352 MHz
  cavities,
• housed per pair in 2 cryomodules
• Very high beam loading (Ysc 10 Ync)
  limit of Robinson instability
• 
  
  (zero margin)

Robinson stability diagram (matched condition,
Pref 0 at max Ib)
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REGULATION LOOPS

• Cure direct RF feedback loop
• RF signal coming from the cavity pick-up
  re-injected into the power ampflifier to reduce
  the impedance seen by the beam

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REGULATION LOOPS

• STORAGE RING PHASE 1
• Booster - like  slow  frequency, amplitude and
  phase loops direct RF feedback

FEEDBACK
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REGULATION LOOPS

• Gain limited by direct RF feedback delay
  Optimization comb-filter
• 
  in
  parallel
• This filter enables us to adjust the feedback
  phase at sideband frequencies

Possibility to reduce selectively the cavity
impedance at the synchrotron sidebands of the
revolution harmonics to cope with longitudinal
coupled-bunch instabilities
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REGULATION LOOPS

• STORAGE RING PHASE 2

Design of fast digital amplitude and phase loops
(collaboration with CEA)
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STORAGE RING CONTROL SYSTEM
LLES Low Level Electronic systems
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SUPERVISION

• PLC structure

STORAGE RING
STORAGE RING
STORAGE RING
STORAGE RING
SIEMENS S7-300
(Cryomodule)
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CONCLUSION

• Regulation loops
• BOOSTER Use of  slow  analogic amplitude,
  phase and frequency
• loops
• STORAGE RING
• Phase 1 booster like system direct RF
  feedback loop
• Phase 2 replacement of the analogic system with
  a digital one
• using fast amplitude and phase loops
• RF control systems
• CPCI gt RF diagnostics
• PLC gt cavities and amplifier interlocks
• Hardwired fast interlocks
• Dedicated PLC for cryo-plant (storage ring)