The 12th Symposium on Accelerator Science and Technology, Wako, Japan 1999

Design of Magnet Rearrangement and Power Supply for SPring-S Storage Ring Long
Straight Sections
Hideki TAKEBE, Kouji TSUMAKI, Hitoshi TANAKA,Kouichi SOUTOME, Keiko KUMAGAI, Hirota YONEHARA, and Noritaka KUMAGAI.
SPring-S Accelerator Division
Koto 1-1-1, Mikazuki-cho, Hyogo 679-519S, JAPAN

Abstract
In the SPring-S storage ring, magnet rearrangement for
four Long Straight Sections (LSSs) will start from June
2000. A detail design for the power supply (PS) of theStorage Ring (SR) LSSs quadrupole (Q) magnets wasstarted from June 1999. A computer control system for thePSs will be the same as the current system of SPring-S
which is VME and RIO stile. Final design and someconsiderations are given in this report.

50g 40·g" 30'•'•'''.
:''''02.,'•'•,,,,''''''

01.5~-'"~~F.

g" 20"'·
g"0~0.5"' 1001 Introduction!;;''ll60

300s[m)Some upgrade plans of the SPring-S storage ring havebeen discussed from the beginning of the project. Since thefirst stage performance of. the SPring-S was successfully
achieved and user operation has been done steadily for these
two years (1997-1999), the next stage project using four.
[I)
LSSs was started in December 199S ·After magnet rearrangement, a drift space of about 27m
becomes available for installation of an insertion device.
Typical betatron and dispersion functions of the normal celland LSS are shown in Fig.l and 2 before and after therearrangement, respectively. The emittance can be lowered
to about 5nmrad. A matching section at each end of theLSS is about lOrn. In this section there are six families of
Q magnets and the betatron functions and phases arematched as shown in these figures. r21 In the storage ring,four magnet-free LSSs will be realized keeping four foldsymmetry.

Fig. 2. Betatron and dispersion functions aftermagnet rearrangement.
The new LSS lattice design was considered with thefollowing limitations : 1) magnets are the same as the used
before, 2) Q magnets between two bending magnets in thenext upstream and downstream cells are rearranged, 3) thesextupo1e (S) magnet is not used, and 4) the required fieldstrength and current of the Q magnets are less than before.
Table I lists the 6 families of Q-PSs, Q magnets types,currents, resistances, inductances and power consumption
and the number of the PSs. The maximum current is
5SOA. Two magnets are connected in series. So, new six
PSs are installed in each A, B, C, D- PS rooms.
Table 1.

J .....- - -g 40

Dispersion

I"'mOb2MagmH.

PS
OutputVolt. kW

Amt
No.

QLP1
QLP2
QLP3
QLP4
QLP5
QLP6

19.5
19.5
40.4
40.4
19.5
16.92S2S52522S
2230
305555
30
30

16.3
16.4
31.2
31.2
16.4
14.S

44444
4~-0";pg"'·
00.5

100030I PS RoomlOSkW

24

R

01.5 .g·c·e" 30"~s" 20~PSMag
Name Type

250g"

Q3
Q5,6
Q9/Q2
Q9/Q2
QS
Q7/Q460s[m)2 Rearrangement of the Q-Magnet
Fig. 1. Betatron and dispersion functions of themagnet-free LSS before magnet rearrangement.

The former Q and S magnets in the LSS (cell No.6, lS,30 and 42) are going to be replaced from June 2000. The Q,S magnets and base girder will be replaced, and cables for-316-

The 12th Symposium on Accelerator Science and Technology, Wako, Japan 1999

the upper side circular cell-to-cell circuit and lower sidemagnet-to-terminal soft cables (LMFC) will also bereplaced (Fig.3, 4). The other normal cell magnets areconnected with the upstream cell and downstream cellmagnets (Jumper). Figures 3-a and 3-b show thisreplacement and connection of the Q magnets, cables andterminals. The new magnet girder is designed with a lengthof 8 m. Some steering magnets and skew magnets are to beplaced. Base-plates for this girder were already constructedin Summer 1999. A detail design of the LSS magnet girder
is shown in Fig.5.
The former interlock system is to be modified for thereplacement of the Q and S magnets. The input circuits ofthe distributed PLC terminals for the LSS magnets are tobe closed.

(a) Former LSS Section

Cell5

Cell6

Cell7

(b) After Removal ofCell7-A, Cell6 and Cell5-C
Example of the QPl cablejam per Connection/"'-..

Q4-7. S3-5 CVS

Cell5

Cell6Ce117

Fig.3 Configurations of present LSS lattice magnets (a) and jumper connection cables after removal of magnets (b).
QLP 1 in the PS room

Rack

Example: QLPl to QLI, QL12 cable Line~

LMFC Cabling.'rL,2_____ - ------ IQ_------- --- -- -:. . ···········""'"'"'···'··--'J' """''"ill~Q7 Q6 Q5 Q4

Q2

Ccll5

Cell6

Ce117

Q3

------ -'l'Fig.4. New LSS installation of the Q magnets, girders, cables and terminals.

J.. L1379.6

14784.92781.57063.0

Fig.S. A detail design of the LSS magnet arrangement and girder.

-317-J.. LQJ

The 12th Symposium on Accelerator Science and Technology, Wako. Japan 1999

3 Power Supply of the Q-Magnet

References

The LSS Q-magnets are designed in mirror symmetry.
So, two magnets are connected in series (see Table 1).
The new six PSs will be settled in each A, B, C, and D PS rooms. Total number of the LSS Q-PS (QLP) is 24.
The six PSs are divided into two groups, 600A 55V typeand 600A 30V type. A detail design for the power supplywas started from June 1999 with Nichicon Elec. Co., Ltd.
A current control and ripple reduction system is used with20kHz switch mode IGBT module. A current ripple andstability are regulated less than 2 x 10- 5 and 5 x 10-S,
respectively. An input voltage is 3 phase AC400 V.
The former 40 Q auxiliary PSs for the LSSs will bedisconnected, and can be used for a correction of the Q
magnet current in the other normal cell. An example ofthis QLP block diagram is shown in Fig.6.
A computer control system for the PSs is the same as
the current system of SPring-8 which is VME and RIO
optical-fiber linked field BUS system. 131 An RIO Mastercard will be installed in the A, B, C, and D PS room's
VME chassis.
The QLPs take an air cooling system. The magnet
water flow switch and coil temperature switches are toconnect to the PS interlock input, directly. The former
B,Q,S PSs are used with a PLC interlock system, but theLSS Q PS takes a direct wire connection system. PS
status bits to the RIO slave card (for the magnet interlockinput) are slightly changed.

[1] H. Tanaka et al., "Design of SPring-8 Storage Ringwith Four Magnet-Free Long Straight Sections",
SPring-8 Ann.Rep.(to be published), ( 1998).
[2] H. Tanaka, K. Soutome, and M. Hara, J. SynchrotronRad. 4,47(1997).
[3] H. Takebe et al., "Magnet Power Supply Control
System for the SPring-8 Storage Ring", Presented atthe 4th EPAC, London, GB. 1827-1829, (1994).

QLP: (LSS Q Magnet PS)
AC400V3 phase Input

20kHz

0'6

Switching Mode
IGBT-,--!~to 1ffi ~ ~agnel

Rll.:rELB

Trn---,-<:0::>-iht-JJI lJ:l~=lrL-f ~~T'------'~==(Two Transfs

Para. for 36kWPS)II

VME, RIO Master:~---------------------------------1
OpticaiFibt."''Fig.6. QLP circuit block diagram.

-318-

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