Transcript System overview, consolidation needs and project planning

LHC Beam Screen Heaters: System overview, consolidation needs and project
planning
4 February 2013 - TE-CRG/JCC (Beam
Screen Heater Review)
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System Overview: instrumentation distributed all around the tunnel
4 February 2013 - TE-CRG/JCC (Beam
Screen Heater Review)
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System Overview: instrumentation distributed all around the tunnel
Sensor
Lhe Level Gauge
Pressure Sensor
Pressure Sensor
Thermometers
GH/GL/PS Signals
Electrical Heater
Electronics
Crate (Cabinet)
Power Source Card
Temperature Pressure Card
Sc Level Crad
Digital In Card
FIP comm card
Location
Lhe-II phase Separator, DFB, Stand
Alone Magnets
Magnets, QRL, DFB
RF Cavities
Current Leads
QRL, Magnets, RF, etc
QRL, Magnets, RF, etc
Electrical Heaters
ON-OFF Valves and Pressure Switches
All
Location
Under main dipole, protected areas
Qty
Type
528
Superconducting Wire
492
36
0
694
8
9336
3300
5172
336
528
1152
2462
Qty
793
1028
Strain Bridge
Profibus PA
694
8
0
0
2256
4148
232
528
0
332
2
0
1044
692
102
0
2056
406
0
Pt 100
Cernox
Pt 100
Pt 100 & Type-J thermocouple
Mechanical Switch
Electrical resistor
Connected
Not Connected Redundant (switch)
Mechanical Assembly
3953
Crate
352
341
1086
COTS based Design
Instrumentation in operation since well before 2008.
All individual components have been qualified for the
expected conditions, examples:
• Temperature sensors: radiation @ 1.8 K, thermal
cycling, etc.
• Pressure sensors: radiation and thermal cycling
• Active and passive electronic components: radiation
& thermal cycling
• …
4 February 2013 - TE-CRG/JCC (Beam
Screen Heater Review)
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System Overview: Cryo-Tunnel Electronics
RADIATION
• Individual Components have been qualified for
the LHC tunnel conditions
• Cards and complete crate radiation tolerant
design has been verified in CNGS
THERMAL DESIGN
• No active ventilation to increase reliability
• Validated by simulation in worst operating
conditions
OVERALL
• Survived with no damage 2008 LHC accident
• Unique accuracy for temperature measurements
• System is presently operational
4 February 2013 - TE-CRG/JCC (Beam
Screen Heater Review)
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System Overview: Beam Screen cryogenic Hardware
Heating cartridge is removable.
Heating element: 100 ohm resistor
Overheat protection: Type J
Most delicate neighbour: current
leads thermalization.
Photos: LHC interconnects.
4 February 2013 - TE-CRG/JCC (Beam
Screen Heater Review)
5
Consolidation : Reason for change
Cards presently deployed are capable of providing 25 W of heating power on the 100 ohm resistor of
the beam screen heater.
Consolidation requires to provide 200 W of heating capacity to regenerate the LHC beam screen by
desorption of gas trapped on its walls.
The LHC tunnel cards used by the cryogenic system provide power as follows
• 0-25 W: variable dc voltage
• 25-500 W: Pulse Width Modulation (PWM) of grid voltage by using a solid state switch
Card capable of supplying 200 W is not compatible with the LHC radiation environment, even if the
range 25-200 W is not used while there is circulating beam.
 New card compatible with LHC background radiation, MOS switch and drive validated @ CNGS
 Comply with additional heater protection mechanism: manual restart on either power-up or
interlock
The heater cartridge is designed for 500 W and is not concerned by this consolidation.
4 February 2013 - TE-CRG/JCC (Beam
Screen Heater Review)
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Consolidation Needs: Proposal
The new card shall be based & installed on the existing equipment
Any new component shall go through a qualification campaign
New ac switch for the range 25-200 W
• The circuit schematics and main components for supplying the range 25-200 W are finalized
• The components have been qualified in the CNRAD for up to 700 Gy
• Additional tests foreseen to confirm RadTol requirements
Parameter
Present design
Consolidated design
AC supply
Through backplane (230 Vac)
Independent supply (230 Vac and lower)
Interlock ON
ENABLED when protection
temperature (TP) exceeds HIGH
threshold or sensor is disconnected
ENABLED at start-up, at reset, when TP
exceeds HIGH threshold (SOFT & HARD),
or sensor is disconnected
Interlock ON
DISABLED automatically when TP is
below LOW threshold
DISABLED by
manual operator request ONLY
AC power control
Non RadTol (Switch degraded by TID)
RadTol (validated in CNRAD)
AC switching
Zero crossing
Zero crossing, Peak or random
Protection sensor
thermocouple
Thermocouple and resistive sensor
PCB track protection
None
Fuse
Power Monitor
Dc mode only
Ac and dc modes
4 February 2013 - TE-CRG/JCC (Beam
Screen Heater Review)
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Beam Screen Heaters: Cost
The cost is not only due to the manufacturing of the electronics but also:
1. Step-down transformer: required to reduce the maximum power that can be applied onto the
beam screen heaters
2. Separate power supply (e.g. new cables and mains switch): past experience suggest that this is a
useful feature in order not to stop the functioning of a full crate in case of electrical failure of the
heater element.
3. QA: testing with automated test bench add a task to existing manpower
Electronics cost has been impacted by significant price increase of anti-fuse FPGAs manufactured by
ACTEL: unit price for similar order quantities: 37.50 USD in 2008 versus 106.- USD in 2012.
However FPGA count per card is reduced from 4 to 2 or 1.
Profit to overhaul:
• 500 W return module heaters that may be affected by SEU (25 cards)
• 100 W “high” dc current that presently use 2 channels in parallel (32 cards)
Individual
Total Cost
Cost
330
1300 429,000.00
50
1300 65,000.00
Quantity
Electronic Cards
Spares 15%
Step Down Tranformer
& enclosure
Spares 10
Mains Switch & Cable
TOTAL
297
10
297
100
100
72
29,700.00
1,000.00
21,384.00
546,084.00
4 February 2013 - TE-CRG/JCC (Beam
Screen Heater Review)
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Beam Screen Heaters: Schedule
•
•
•
•
Card design require the validation of a few prototypes ideally operated in real conditions
Some components may require very long delivery delays
example 2007: 26 weeks delay for the ADS7807UB ADC => order ASAP
Assume:
• PCB design, PCB manufacture & PCB/card assembly by TE-MPE-EM
• Punctual help for consolidating the automated test bench LabView code (BE-CO-HT)
Presented schedule is the “fastest”, longer prototype testing is preferable
=> ordering of cards series to be delayed as permitted by LS1 schedule
4 February 2013 - TE-CRG/JCC (Beam
Screen Heater Review)
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