Commissioning and Operation of SSRF

Wenzhi ZHANG for the SSRF Physics and Operation GroupShanghai Institute of Applied Physics, CAS, ChinaApril 22, 2010

Contents• Brief introduction of SSRF
• commissioning of Booster• commissioning of Storage Ring
• Operation status of SSRF Storage Ring
• SummaryShanghai Synchrotron Radiation Facility
SSRF is an intermediate energy 3rd generation light source
funded by Chinese Academy of Sciences (CAS), Shanghai
local government and central government of China;

CAS and Shanghai local government made a joint proposalin 1995, and then a R&D program was carried out from Jan.
1999 to Mar. 2001; Later on this project was announced andfully approved in 2004, and its groundbreaking was made onDec.25, 2004;
The Linac and booster have been commissioned in 2007, thestorage ring commissioning and the beamline commissioning
started on Dec. 21, 2007 and May 9, 2008 respectively. The
user operation is scheduled to start in May 2009

SSRF Complex

Key Dates of the SSRF Commissioning

Firstbeam

25/07

15/05

ready

15/05/07

3.5GeV

05/10

29/10/

24/12

Extraction

accumulation

Booster

Storage Ring

30/9

21/12

300mA

18/07/09

SSRF BoosterThe SSRF Booster and its commissioning
A full energy booster optimized for top-up injection;

Two fold Lattice configuration to accommodating 28 FODO
cells with 8 missing dipole magnets;
Extraction beam emittance designed at ~100 nm-rad forgetting a clean top-up operation;
A circumference of 180m and a injection energy of 150MeV;
Repeat rates up to 2Hz

Main Parameters of the SSRF Booster

One FODO cell

The SSRF Booster Installation

Booster Commissioning Milestones
Sept. 30: Commissioning started at 20:30, and beam arrived
at the booster entrance at 21:58;
Oct. 01: First turns of the circulating beam in booster
achieved at 17:00;
Oct. 02: First stored beam in the booster obtained at 4:30;
Oct. 05: Within 60 effective commissioning hours, first
ramped beam (3.5GeV) obtained at 4:25;
Oct. 29: First extract beam from the booster achieved

Oct. 1st, night, stored beam was observed by set the sextupoles, RF on

WCM

Oct. 5th, The beam was ramping to 3.5 GeV

Oct. 29, Beam was extracted to the HBTOverview of Storage Ring

Main Parameters of the SSRF Storage Ring

The SSRF Storage RingA 20-cell double bend lattice structure with a circumferenceof 432 m and a natural emittance of 3.9nm-rad;4 fold configuration with two types of straight sections(16x6.5m and 4x12m );One 12m straight for accommodating all injection elements,
another one for SRF cavities and other 18 for various IDs;

Reasonable beam sizes, beta functions
and dispersion at straight sections;Storage Ring
Main parameters:

Energy：3.5 GeV；Circumference：432m；
Current：5/300 mA (S/M bunch)；emittance：3.9 mm-mrad；Strait section：4*12m，16*6.5m；
RF voltage：4-6 MV

Max Power：~600kW
Orbit Stability：<10% beam sizeDesigned Lattice Parameters
Mode I

Mode II

Mode III

Mode IV

Tune

22.22/11.29

22.22/11.29

23.32/11.23

19.22/7..32

emittance

3.92

11.4

3.36

5.42

The SSRF Storage Ring Installation

Commissioning of SSRF storage ring
1. Commissioning Schedule: First stage: with norm RF cavities (Vrf 2.0MV, Eb 3.0GeV ) Second stage: with supper-conducting RF cavities (Vrf 4MV, Eb 3.5 GeV) Third stage: with insertion devices and beam lines
2. Commissioning procedures: Beam injection: First turn and multi turns
 beam current accumulation and Stored beam
 COD
 BBA
 LOCO Beam orbit stability and slow orbit feedback
 Insertion devices
 High current

Storage Ring Commissioning Milestones
Dec. 21, 2007: commissioning started at 18:20, one turn beamachieved at 21:08 and multi-turn beam at 21:18;
Dec. 23, 2007: 2000~3000 turns achieved at 20:00;
Dec.24, 2007: first stored beam obtained at 06:54 (in~60hrs)
Jan.03, 2008: 100mA stored beam achieved at 20:20;
Mar. 16, 2008: Both horizontal and vertical closed orbit
corrected to <50um rms with 80 correctors (137BPMs);
June 2008: a few of microns beam orbit stability achieved;
June 15, 2008: Integrated beam current >150 Ahrs obtained;
June 17 -18, 2008: 200mA at 2GeV and 300mA at 1.5GeVachieved.
2008.09.30 Reached 200mA@3.5GeV2009.05.06 Open to user
2009.07.18 Reached 300mA@3.5GeV

Storage Ring CommissioningCelebrating the Stored Beam 06:55, Dec.24, 2007

On July 18, 2009 , the final important parameter 300mA was reachedModel Calibration

The main design values of the two modes
Parameters

Dispersion mode

Dispersion-free mode

Energy (GeV)(3.0)3.5(3.0)3.5

Circumference (m)

432

432

Cell

20(DBA)

20(DBA)

Super-period

44

Tune Qx/Qy

22.22/11.29

22.22/11.29

x/y/x(m) in the centers ofstraight sections

10/6.0/0.15
3.6/2.5/0.10

10/6.0/0
3.6/2.5/0.006

Natural emittance (nm.rad)

3.92
2.86@3.0GeV

11.4
8.4@3.0GeV

Natural chromaticity x/y-55.64/-17.94-55.56/-18.09

Momentum compactor

4.2118×10-4

5.4249×10-4

Damping partitions Jx/Jy/Js

0.9968/1/2.0032

0.9960/1/2.0040

Natural energy spread (rms)

9.84×10-4
8.44×10-4@3.0GeV

9.84×10-4
8.44×10-4@3.0GeV

The optical functions of the two modes in one fold of the storage ring

Dispersion
mode

30[m]

Dispersion-free25
mode
20

x

y

15
10x *50

5005102030

4050

60

70

80

90

100

102030405060
S [m]

7080

90

100

0-50Calibration the model step by step
1. First commissioning
Tune difference from model: 1.5(H)/0.4(V)rms value of COD is about 1mm in both plane

2. Model calibration after two rounds of BBA
Tune difference from model: 0.03(H)/0.07(V)rms value of COD is about 0.08mm in both plane
Bad beta function distributions

3. Model calibration with LOCO: by family
The measured data are almost same with the modelrms value of COD is less than 0.05mm in both plane
Working with 100mA

4. Model calibration with LOCO: by magnets
Reduce the beta beating caused by the small errors

Bare COD

Step 1: Commissioning mode within the first monthStep 2: Commissioning mode after two rounds of BBA

BPM offsets
Feb. 23 2008

 After two rounds of BBA, the closed orbit can be corrected sufficiently,(x/y(RMS)=0.08mm/0.09mm @2008/2/24). With a simple scaling of magnetic
coefficients, the measured optical parameters are close to the ones of the model.
 The measured tunes are 22.196/11.214, and the measured chromaticities are about 58/-16.
 Unfortunately, the measured beta functions show bad periods, and have muchdifference with the model!

Step 3: Commissioning mode with LOCO ( By family) Correction of the B-I is done by fitting the quadrupole fields
family-by-family with LOCO, and correction the magneticcoefficients.
 The commissioning is changed to dispersion mode after Mar. 5,
2008
 The closed orbit can be corrected to 0.07/0.08 mm (RMS) forhorizontal and vertical plane respectively。
 The measured tunes (Qx/Qy) are 22.26/11.28, which is close
to the designed value (22.22/11.29) further.
 The measured beta functions have good periods!

Beta and dispersion beatings between the LOCO model and the designed mode0.2

 x / x0.15

 y /y /

0.1
0.05
0-0.05-0.1-0.15-0.2

•

050

100

150

200
S [m]

250

300

350

400

Aberrations of the optical functions are obvious. The fact can be found both in direct
measurements and LOCO measurements.

Step 4: Commissioning mode with LOCO ( By magnets)
 With the little difference between model and measurement,
one can use LOCO (fitting magnet-by-magnet) to calibrate therealistic mode to be closed to designed mode.
 After calibration of two rounds, the operational mode is tuned
to designed mode, and the direct measured parameters arecoherent to values resulting from LOCO measurements, andthe designed mode.

Optical functions resulting from calibrated model with LOCO

Hori. beta

Vert. beta

Comparison of the dispersion between the LOCO model and the designed mode tracked withAT code0.3

x [m]

0.25
0.2
0.15
0.1
Tracking results from LOCO model
Tracking results from designed mode

0.05
0020

40

6080
BPM index

100120140

Beta and dispersion beatings between the LOCO model and the designed mode

0.05
0.04
0.03
0.02
0.01
0-0.01
-0.02
-0.03
-0.04
-0.05

 x / x050

 y / y100

 /
150

200250S [m]300350400

BBA measurement results

Residual closed orbit at 100mA: <50um rms

Orbit Stability

Orbit drift without feedback

SOFB results on 2008.06.04
The last orbit difference with the initial value
Total
SOFB
time:
5.5hours

Horizontal

VerticalBPM
number:135

Eigen
Values:
60/60
(H/V)

Orbit drift in the last 5.5 hours

HVSOFB results started from 2008.12.01 23:00, 14 hours

80个BPM
Eigen values

H : 40V : 60x/y (rms)~ 2 m /1m

Operation Status

In 2009

Accelerator Operation Status– 2305 hours for machine study– 4317 hours for beam line
• 2620 hours for beam line commissioning• 2093 hours for user time operation– 372 hours hardware failure– 1286 hours for maintenanceMachine Statistics for user operation•••••

Total time : 2093 hours
Hardware failure: 120.6 hours
Availability: 94.6%
MTBF:
31 hours
MDT:
1.6 hours

Hardware failure statistics
PPS
4.7%
Vacuum0.8%

Beam accelerator physics
BI
2.5%
line
4.5%
4.1%

Injection andextraction
12.5%
工艺
0.4%
Power Supply
14.6%

Control
0.6%

Utilitysystem
23.2%

RF system
31.1%

Injector
0.9%

Summary
The SSRF accelerator commissioning was carried out
rapidly, smoothly and successfully; Some problems we have to solved in the future
operation
 BPM jump;
 Decrease hardware failure time; Increase MTBF > 50 hours;

 SOFB and FOFB work together; Top up Operation;