ExtractionKicker of SIS100

Kicker system of SIS100 is responsible for normal extraction as well as for emergency dump of the the beam.

The kicker system provides bipolar operation. Output of the HV supply can be connected in two ways with the kicker magnet, providing opposit polarity of the current. One polarity directs the beam into the extraction channel, the other polarity directs the beam into the beam dump.

Topics which are relevant to control the kicker system, as are known up to now:

• kicker is combined of 8 identical modules. Each module consists of
  • one single power supply
    • directly loading the energy storage, no HV transformer as in SIS18 (and CR)
  • high voltage switches (probably thyratrons)
  • energy storage- no cable, but a system of capacitors and inductivities, replacing the (otherwise very long) cable
  • one kicker magnet in the beam tube
  • trigger delay (one per module), to compensate differences between modules
• modules are arranged in 3 groups
  • 3, 2, 3 modules
• additionally, quite sure there will be one single trigger unit to fire the kickers
  • part of kicker? check!
• HV power supplies must be ramped
  • required by emergency kick: at each time in accelerating cycle, kicker must be prepared to direct beam into beam dump
• after accelerating cycle, HV power supplies will be ramped down to low voltage (to be ready for next accelerating ramp)
  • other than in SIS18 kicker, no rest-charge will be kept (no restriction of voltages to be at least half of the voltage of the previous kick)
• also: trigger generation must be ramped
  • correct for delay between trigger and the kick
    • may be 1, or mnaybe even up to 30 µs
    • beam gap moves different lenght at injection and at extraction (revolution time: see below)
  • however, trigger ramping is assumed to be done not in the kicker but in a central trigger generator
• interface of HV power suply to controls: U. Blell envisages SCU with an ACU
• range of HV power supply: 0 .. 80 kV
• planed operation range of kicker: 8 .. 70 kV
• one kick per cycle, contents of SIS100 will be extracted as a whole
  • duration of kick (flat-top): 6.7 µs (rise time 730 ns)
    • maximum energy: revolution time in SIS100 is 3.6 µs
    • injection energy: revolution time bigger (around 5 µs)
  • SIS100: 10 RF-buckets, 8 bunches
    • 2 buckets empty, to provide time for rise of kicker pulse

besides extraction (emergency) kicker there will be other kickers which will be operated in resonant mode (capacitor, then charge cable) as is SIS18-kicker

Software Modellation:

• P. Spiller requests (mail to D. Ondreka, R. Bär et al from 05-Jul-2010): each of the 8 kicker module must be modelled as independent device, not combined to a resulting kicker (as is done in SIS18)

Appendix Alex Schwinn - From a meeting with The Kicker group & RI(formerly Ampegon):

Like the SIS100 Injection Kicker, a PLC will be used to control and coordinate the different kicker modules. Various parameters can be read out via that PLC.

• RI would require an example ramp to be played for testing (SCU create bootet from USB, using fesl-only?)
• RI tells that the Power Supply will support only up to 100kHz rates for setting setting values / requesting acquisition values
• RI will build the SCU Interface and PLC registers similar to the SIS100 Injection Kicker
• One SCU-crate per kicker-module

Open questions:

• Who is going to develop and maintain the related fesl-device and fesa-class ?
• Will that be a PowerSupply FESA class which uses Silecs ? (6 instances)
• Or a central fesa-silecs class, talking via network to each of 6 PowerSupply class instances ?
• Or something else ?