Status of the Fast Orbit Feedback System Development for TLS

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Status of the Fast Orbit Feedback System
Development for TLS

• Chang-Hor Kuo
• NSRRC, Hsinchu, Taiwan

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TLS
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Outline

• Status of TLS
• Fast orbit feedback system in the TLS
• Current status limitation
• Upgrade plan goals
• BPM will migrate to support EPICS applications
• Efforts of fast orbit feedback system in the TPS

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Todays Experimental Floor of TLS
Scarce beamline ports available Unable to produce
high brightness synchrotron in x-ray range from
the existing 1.5 GeV ring
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TLS Current Status
300 mA Top-Up operation lt0.1 photon flux were
achieved routinely
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Current Status Orbit Feedback System for TLS

• Orbit feedback system was deployed a decade ago.
• Switched electrodes BPM electronics support only
  for closed orbit measurement
• Old linear type power supply
• gt Heavy (maintenance is no easy)
• Original system is a DSP based feedback system
• Migrate to PowerPC to meet various requests.
• gt 5 Hz mechanical vibration
• Achieved orbit performance 1 mm (DC 5 Hz)
• Improve functionality to support various study

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(No Transcript)
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DSP ? PowerPC (2001)
PC
Control
Consoles
Control
Network
Orbit Acquisition
Reflective Memory
Corrector Control
VME Crate
Hub
VME Crate
V
V
M
M
16
16
16
16
16
16
(G4)
E
E
Bit
Bit
Bit
Bit
Bit
Bit
Feedback
RM/
RM/
RM/
VME Host
D
A
A
A
D
D
PowerPC 7410
DMA
DMA
DMA
VME
H
H
A
D
D
D
A
A
Timer Generator
O
O
C
C
C
C
C
C
Crate
S
S
T
T
In project..
Private Ethernet Switch
Correction Magnet Power Supply
Electron BPM
end
PBPM Front
-
end
PBPM Front
-
end
PBPM Front
-
Photon BPM
Orbit Feedback
System Upgrade, June 8, 2001
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Reasons for the FOFB Migration
Reasons for the upgrade of orbit feedback
system Orbit feedback system was deployed a
decade ago. Response time is limited by Power
supply, BPM performance, eddy current
effect Perturbation from fast sources cannot
removed effectively gt 5 Hz mechanical
vibration Fast operation of insertion
devices Achieved orbit performance 1 mm (DC 5
Hz) Improve functionality to support various
study Used as test-bed to exercise TPS orbit
stabilization techniques
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Upgrade Plan in the Orbit Feedback

• Approaches
• BPM upgrade
• Better performance, rich functionalities
• Corrector PS upgrade
• Wide bandwidth, modulated to easy maintenance,
  low noise
• Infrastructure upgrade
• RD of various issues for fast orbit feedback
  techniques
• Test-bed for beam stabilization system for
  Taiwan Photon Source.

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Components for the Fast Orbit Feedback System
BPM New generation digital BPM electronics (10
kHz update rate, gt 1 kHz BW) Orbit
measurement Slow orbit measurement gt 10
times/sec to control servers/consoles. Fast
orbit acquisition for feedback purpose 10
kS/sec, sync by event system. Share orbit
information among feedback processors via a
dedicated fiber link Block data capture is
included for diagnostic purposes Corrector
control Analog sum. (Digital power supply is
preferred for feedback corrector control GbE
interface for fast corrector setting by UDP
broadcasting 10 k update/sec 16 bit
control resolution Historical recording is
included for diagnostic purposes) Feedback
Processor and Algorithm PPC Feedback engine
LynxOS Various control rules can be chosen Fast
orbit feedback gt dedicated feedback system
Corrector maximum steered angle 1 mrad
(lt 10 Hz) 100 mrad _at_ 60 Hz
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Integrated into EPICS Environment
Time scale viewpoint Oribt feedback
EPICS
100us
10 500ms
?
Solutions

• NEW BPM upgrade for orbit feedback
• BPM access interface migrated to EPICS
• from original interface .
• TPS

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New BPM Integration Structure
TLS Control Network 140.110.202.xx
EPICS OPIs and Clients
Control Console
Control Console
Control Console
EPICS
broadcast
ILC
ILC
ILC
FOFB Corrector Control
FB Node VME RM ?? PMC RM
ILC
EPICS Gateway
Gateway ILC10 to TLS ILC database
ILC
ILC07 VME RM ?????
Diag. Node
RM Network
TPS Control System Development Network
EPICS Gateway
ILC12 ????? VME RM
EPICS
Data Acq Node 1
Data Acq Node 2
Why Libera IOC? Avoid efforts of duplication
works (TPS)
SA Ethernet Switch
Libera Brilliance X 59
R1 BPM (10)
R2 BPM (10)
R3 BPM (11)
R4 BPM (10)
R5 BPM (10)
R6 BPM (8)
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Components for the Fast Orbit Feedback System
PC/Linux
WS/Unix
PC/Linux
Control Consoles
Control Network
Reflective Memory Hub
Diagnostics Node
V M E H O S T
16 Bit D A C
16 Bit D A C
V M E H O S T
16 Bit D A C
16 Bit D A C
16 Bit A D C
16 Bit A D C
PMC RM
PMC RM
VME Host PowerPC 7410
GbE Interface
Corrector DC Control
Fast Orbit Feedback VME
GbE Switch
GbE Switch
Trigger
Libera Group 1
Libera Group 4
PS Control Summing Amplifier
Libera Group 2
Libera Group 5
Libera Group 3
Libera Group 6
Super-period 1,2,3 BPM
Correction Magnet Power Supply
Super-period 4,5,6 BPM
January 11, 2008
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Communication Test for the BPM Electronics
Challenge Fast Access from BPM
PowerPC
DA converter
PowerPC with LynxOS 4.0 real time
operation difference packet ? difference High/Low
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1 libera
2 liberas
6 liberas
7 liberas
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Solutions Libera Grouping
Goal to reduce communication overhead
To Fast Orbit Feedback System
Redundancy linkt is possible (To Fast Orbit
Feedback System)
Master
Slave
Slave
Slave
Libera Grouping
Multi-gigabits bidirectional links
BPM
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Beam Spectrum Observed by Libera
Upgrade of the TLS orbit feedback system is
schedule in 2008. Practice all necessary
techniques at TLS
Quadrupole Vibration Spectrum (Horizontal)
R1BPM8 Observation (Libera Electron)
Horizontal Position Spectrum
After removed some found sources (Hor.)
Vertical Position Spectrum
Horizontal Integrated Displacement
Vertical Integrated Displacement
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New Corrector Power Supply
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Power Supply Performance Comparison

• The figure shows performance of linear and
  switching power supply in standard deviation. The
  standard deviation of 0.6 mA of vertical plane
  power supplies are due to analog-to-digital data
  acquisition module performance.

Old PS for horizontal correctors
New PS for vertical correctors
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RD Lists
Infrastructure Topology RD Grouping of BPM with
GbE interface Feedback computation Fast
corrector control Low latency communication Diag
nostics How to share fast orbit data among
processors (Share memory or another
approach?) gt current planned aTCA
solution Feedback System Modeling Transfer
function of various system components Beam based
system identification Effectiveness of the
BPM/corrector selection System
modeling Quadrupoles motion Power supply
noise and ripple BPM performance Control
rules Measurement response of various
components Control rules development
Jitter of the GbE link Solutiongt Grouping of BPM
Test done at TLS
Response of the vertical plane.
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FOFB Feedback Loop Simulation
P
Reference Orbit

UT
W-1
V
Corrector
I
-
D
Response Matrix R V W UT
Accelerator
Vacuum Chamber
BPM

Measured Orbit Measured Noise
Orbit Disturbance due to various sources
Orbit
squad vib 1 mm, sBPM noise 0.25 mm, sCorr
noise 10 nrad
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FOFB Feedback Loop Simulation cont.
Quadrupole Vibration Effect
Power Noise Study
sCorr noise 10 nrad
squad vib 1 mm
Feedback Loop Frequency Response Study
Static Feedback Effectiveness
squad vib 1 mm, sBPM noise 0.25 mm, sCorr
noise 10 nrad
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Summary of TLS FOFB System

• TLS FOFB system is being implementation
• Orbit control for insertion device operation.
• New high resolution fast access BPM.
• New wide bandwidth and high performance
  corrector power supply.
• System will deploy before the end of 2008
• Fast IDs operation
• Improve orbit stability

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Proposed Infrastructure for the TPS FOFB
TPS Control System
Control Network
AdvancedTCA Crate, with Switch Blades, Compute
Blades, And Build in Diagnostics
Centralized or Distributed computation can be
decided later!
GbE Fiber Link (Setting Only)
Full function control access at slow rate
PS controller, Concentrator 1
PS controller, Concentrator 2
GbE Fiber Link (Read Only)
PS controller, Concentrator M
Power supply
PS 2
PS N
PS 1
PS 1
PS N
PS 2
XBPM
PS 2
PS 1
10 kHz rate interface
XBPM
PS N
TPS Ring
XBPM
XBPM
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Current Efforts for TPS FOFB

• Infrastructure study
• BPM electronics and communication protocol study
• Power supply control interface study
• Computation engine study
• The FOFB system can be distributed or
  centralized
• Pros and Cons study
• System latency time design
• Algorithm development

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Thank You for Your Attention!