Transcript BPMs and Diagnostics

EBPMs and Orbit Feedback
Electronics for Diamond
IWBS 2004
Guenther Rehm
Guenther Rehm
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Outline
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BPM locations and cross sections
BPM response calculations
EBPM performance examples
SOFB plans
FOFB plans
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Number of BPMs
Location
Count
Type / cross section
LINAC
0
-
LTB
7
Stripline / circular
Booster
22
Button / elliptical
BTS
7
Stripline / circular
SR
120+48
Button / octagonal+oval
Sum
204
All with Libera EBPM electronics
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Storage ring BPMs
• Primary BPMs:
– Increased sensitivity through smaller aperture
– Mechanically decoupled through bellows
– Position monitored relative to reference pillar
• Standard BPMs:
– BPM blocks welded into vacuum vessel
– Mounted on “anchor” stands
– Position monitored relative to quad centre
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BPM locations in SR
10
5
0
-5
-10
-40
-30
-20
-10
0
10
20
30
40
Primary BPM
20
10
Standard BPM
0
-10
-20
-50
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-40
-30
-20
-10
0
10
20
30
5
40
BPM response calculation
• MATLAB based boundary element solver
– Fast: 5.5 sec on P4/1700 for 722 boundary
elements and 441 beam positions
– Precise: results checked with finite element
solver (Vector Fields OPERA)
• Geometrical manufacturing uncertainties
have been modelled using Monte Carlo
simulation
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Calibration Factor for Primary BPM
calibration factor [mm]
14
13
Kx
Ky
12
11
10
9
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2
4
6
offset from centre [mm]
8
7
Nonlinear 2D BPM response
BPM reading
real position
10
9
8
beam y offset [mm]
Needs to be
corrected
before
nonlinear
beam
dynamics
studies!
7
6
5
4
3
2
1
0
0
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2
4
6
beam x offset [mm]
8
10
8
Resolution with 1 kHz BW
10
1
RMS (µm)
10
2
10
0
-1
10
-80
-70
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-60
-50
-40
Pin(dBm)
-30
-20
30 mA
-10
0
300 mA
10
RMS noise with
1 kHz Bandwidth
Beam
current
Primary x/y in µm Standard x/y in µm
60-300 mA
0.27/0.3
0.65/0.45
10-60 mA
0.54/0.6
1.3/0.9
1-10 mA
1.35/1.5
3.3/2.2
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Control and Instrumentation Areas
(CIAs)
L
WAL
ILD
SHE
ER
150\ U+ 2 205 DUCTS
450 CAB LE TRAY
RA C K 1
C ON T ROL, NE TWORK
& T IMIN G
DIS T RIB UT ION
RA C K 6
DIP ,QU A D & S EXT
P OWER S U P P LIES
A N D C ON T ROL
RA C K 11
S TEE RIN G
P OWER S U P P LIES
A N D C ON T ROL
RA C K 2
P ROT EC T ION
A N D C ON T ROL
RA C K 7
DIP ,QU A D & S EXT
P OWER S U P P LIES
A N D C ON T ROL
RA C K 12
S TEE RIN G
P OWER S U P P LIES
A N D C ON T ROL
RA C K 16
V A C U UM
IN S TR UMEN T A TION
A N D C ON T ROL
RA C K 17
V A C U UM
IN S TR UMEN T A TION
A N D C ON T ROL
RA C K 3
DIA GNOS TIC S
A N D C ON T ROL
RA C K 8
DIP ,QU A D & S EXT
P OWER S U P P LIES
A N D C ON T ROL
RA C K 13
IN S ERT ION DEV IC E
MOTOR D RIV E
S YS T EM A ND
C ON T ROL
RA C K 18
F RONT EN D VA C U U M
IN S TR UMEN T A TION
A N D C ON T ROL
RA C K 4
DIA GNOS TIC S
A N D C ON T ROL
RA C K 9
DIP ,QU A D & S EXT
P OWER S U P P LIES
A N D C ON T ROL
RA C K 14
IN S ERT ION DEV IC E
MOTOR D RIV E
S YS T EM A ND
C ON T ROL
RA C K 19
F RONT EN D VA C U U M
IN S TR UMEN T A TION
A N D C ON T ROL
RA C K 5
S P A RE
RA C K 10
S P A RE
RA C K 15
S P A RE
RA C K 2 0
S P A RE
DISTRIB UTIONDISTRIB UTION
B OA RD
B OA RD
E
EXACT REQUIREMENT FOR
150\ U+ 2 205 CAB LE DUCTS
WILL B E DEPENDANT UPON
CAB LE QUANTITIES &
EQUIPMENT LOC ATIONS
24 temperature stabilized CIAs for 19” racks
PLAN VIEW ON ACHROMAT 1
DEPICTING CAB LE ROUTING
( FRONT END & DIPOLE CAB LE DUCTING NOT SHOWN)
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SOFB Setup
One CIA
VME
PSU IF
PSU IF
Processor
Central
feedback
calculation
14+8 Corrector PSUs
PSU 1
…
PSU N
Controls Network (EPICS)
eBPM
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eBPM
eBPM
eBPM
eBPM
eBPM
eBPM
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SOFB Details
• EPICS IOCs run inside LIBERA
• EPICS interface to PSU already available
• MatLab channel access makes application
development easy
• Can be tested with “virtual accelerator”
• Expected to run at 10 Hz sampling, 0.5 Hz
closed loop BW
• Will be available on day 1
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Virtual Accelerator and Software
Commissioning
Physics
Application
Software
Real
Accelerator
Virtual
Accelerator
The Virtual Accelerator is used
1) to simulate the control system environment as seen by the users
2) to provide a realistic test for AP applications
The Virtual Accelerator uses the Tracy–II code to simulate the physical
behaviour of the ring
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Basic Virtual Accelerator
Functionality
• Set magnet currents
• Read EBPM x/y
average calculated
using Tracy2 closed
orbit
• Read EBPM x/y turnby-turn buffer using
Tracy2 particle
tracking
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EPICS
EPICS
EBPM
MAGNET
TRACY 2
16
“measured” Response Matrix
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MatLab AT Based Feedback
Orbit Correct implemented using AT for Spear 3
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Design constraints for FOFB
• Global system, all data should be available
everywhere
• Low latency from hardware, main delay should
result from LP filter
• FB algorithm should be easily serviceable
• Corrector PSU interface is VME
• Robust system which continues to perform with
partial faults
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FOFB Setup (one CIA)
Controls Network
Event Network
PMC Rocket IO
PSU IF
PSU IF
FB Processor
ADCs
Event Rx
Processor
VME
Photon BPMs
pBPM
14+8 Corrector PSUs
PSU 1
pBPM
eBPM
Cell -n
eBPM
eBPM
eBPM
eBPM
eBPM
…
PSU N
eBPM
Cell +n
Cell +m
Cell -m
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FOFB Details
• FB data produced at 4-20 kSamples/s
• Dedicated FB CPU board MVME5500 running vxWorks,
but no EPICS IOC, no network.
• RocketIO in Virtex2Pro to run at 2.5 Gbit/s
• PMC card with RocketIO will be board developed for
timing system
• Connections inside rack can be galvanic, longer
distance will be single mode fibre
• All connections between CIAs will be patched centrally
• Communication is broadcast, no routing or location
information is required for any node.
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FOFB Delays
(simulated/estimated)
• Distribution of 168 sets of data to 168+24
locations: 30 µs
• Transfer to CPU: 10 µs
• Matrix multiplication: 30 µs (worst case)
• Write into PSU: 50 µs
• 200-400 µs delay for LP filter
– > feedback BW >>100 Hz should be feasible
• Detailed simulation is required!
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Acknowledgements
• DLS: Mark Heron, Ian Martin, Riccardo
Bartolini, Tony Dobbing
• Instrumentation Technologies
• Supercomputing Systems
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