Control Group Report
Hiroshi Kaji
on behalf of SuperKEKB Control Group

2Control System Overview
The SuperKEKB control system manages
the hardware belonging to ~3km beamline.
EPICS Input/Output Controller (IOC)configured with VME, PLC, ...
Console with the Operation Interface (OPI)based on the SAD, Python, CSS, ...
Dedicated network

26 sub-control rooms~150 IOCs~10000 components
After the phase-1 operation, control group worked for the DR operation and theimprovement of the SuperKEKB drivability.

Web-based Monitoring System
Web-based monitoring system is developed with Grafana. https://grafana.com
Network Monitoring
The infrastructure of control system (likeserver/network/IOC) is monitored.
Information is collected with Zabbix.

https://www.zabbix.com
https://grafana.com/plugins/alexanderzobnin-zabbix-app

IOC Monitoring

Server Monitoring3

Web-based Monitoring System – ctd

S. Sasaki, “Web-based Data Visualization Using EPICS pvAccess RPC at SuperKEKB”,
in proc. of 15th annual meeting of PASJ.
In addition, we utilize the Remote Procedure Call (RPC) of the EPICS 7 protocol.
It enables us to collect more complicated information.
The arbitrary constructor of the EPICS PV information can be transferred.

Alarm monitoring:The data protocol includes the “severity”
and “status” fields.

Abort signal sorting:
The data protocol includes the “time” field.

45Timestamp synchronization

S. Sasaki, et al., “Upgrade of Abort Trigger System for SuperKEKB”,in proc. ICALEPCS2015, Melbourne, Australia.
H. Kaji, et al., “Time synchronization for Distant IOCs of the SuperKEKB accelerators”, in proc.
IPAC2017, Copenhagen, Denmark.
Note, we discuss the timestamp (CPU clock) of the control system rather than the timing.

The CPU clocks of all Event Timing System and Abort Trigger System modules aresynchronized with the accuracy of ~1µs.

- The timestamp of all Event IOCs is synchronized by the delivery of the special kind of Events.
- The common timestamp is delivered for all Abort Trigger modules.
- The EVR is installed on the master IOC of Abort Trigger System⇒ Two systems are combined and LINAC and MR have common timestamp.

ReceiverKEKB rev.
Receiver
EVR

Master IOC#0x70, #0x71, #0x7D

Injection
Hardware

AC IN

IN0EVG

Abort analysis with timestamp
6/1 21:19 LER D6V2 LM
Seimiya-san and his team determine there is a coincidence of the abnormal LINAC
abortpulse and the LER abort.

Abort:
LINAC pulse:

Abnormal energy shot is observed.

-20mm@SP613(hx=1.68 m) ⇒ ΔE = -50MeV
They confirmed “the klystron, KL_51, is downat this pulse”.
This low energy pulse is possible to be
injected at LER.
d ~ 1.2%→ d ~ 0.4% (after ECS) < BT Acceptance

We assume this pulse causes the LERabort.

6/1 21:19:47.785007
6/1 21:19:47.784

Dispersive point

Straight line

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7

Beam Permission and Beam Gate
Upgraded for satisfying the DR operation
Beam Permission:- kind of machine protection system- Logic enables the accelerator operation when the proper condition is satisfied.
- It includes several operation modes for DR
Beam Gate:- Switch for operators which turn on/off the LINAC operation.
- It is integrated in the Beam Permission logic.
Beam Permission Logic 2018/07/11 updated

LER Beam Gate

HER Beam Gate

8

Beam Permission for DR
Three kinds of operations arepermitted with this “or” logic.

DR operationThe
commissioning
is possible.
of DRFC andinjection
upstream
BT iscomponents
possibleevenisthoughpossible
theevenDR isthough
not ready.
the DR and its BT is not ready.

LTR dump

SY2 dump

9Synchronized Control of Injection Hardware
H. Kaji, et al., “Beam Gate Control System for SuperKEKB”,in proc. IPAC2018, Vancouver, Canada.

The enable/disable control of the injection
trigger is implemented on EVGs.
The control signal to the gun circuit is the TTL
level signal since it is located nearby.
Those for DR and MR hardware is theDistributed Bus Bit (Dbus) signals.

The triggers for all hardware are enabled/disabled synchronously.
The DR extraction hardware is controlled with the appropriatedelay (DR storage time) from the DR injection hardware.

10Comparison of Top-up Injection in Phase-1 and Phase-3
The Beam Gate signals for individual hardware are synchronized andthe system becomes robust.
The frequent switching of Beam Gate becomes possible.

⇒ Top-up parameter is improved.
Example of 4 hours operation in Phase-1

Example of 4 hours operation in Phase-3

Refill is performed with 5% loss.

Refill is performed with 1% loss.

In the rough estimation with formula, L ∝ ILERIHER,
It seems the loss of integrated luminosity is suppressed with new parameter.
We believe the upgrade of Beam Gate is excellent work!

Archiver Status
The control group supports the following two archivers so far.
KBLog:- Main archiver from the KEKB project- All necessary information for the operation is recorded.
CSS archiver:- Sub system for the limited uses.
- The data of QCS and Belle solenoid are archived.
EPICS Archiver Appliance:- Test operation with the small users is performed.
- The stress test is scheduled during this summer shutdown.
- We plan to release to all SuperKEKB members from the autumn run.
Injection Archiver:- The injection data are recorded for all injector pulses.
- Two systems are operated (CSS and AA).

1112EPICS Archiver Appliance
EPICS Archiver Appliance is an open source archiver developed at SLAC.
It is fully utilized in the accelerator operation at J-PARC.
The high performance is reported by the J-PARC control group.
- 1/4 data volume as compared with the CSS archiver- Quite high speed retrieval
All data of the luminosity scan in phase-2 and phase-3
are recorded. The panel for data retrieval is developed.

CSSAA1hour

1.236s0.136s24hour

24.229s0.150s3days

637.408s

2.408sRetrieval time for the 1Hz processing PV data

The test operation is performed with twoservers and two clusters.

We perform the stress test during this summer shutdown.
The service will be provided for all SuperKEKB users before the next operation.

13Injection ArchiverH. Kaji, et al., “Archive System of Beam Injection Information at SuperKEKB”,
accepted by Journal of Physics: Conference Series

DI = Ibunch(after) – Ibunch(before)

DILER (mA)

The injected current, DI, is determinedfrom bunch current monitor as follows:

ILER (mA)

Injected current is determined and recorded for all injector pulse.
400350300
250200150
100
5000.180.16
0.140.120.1
0.08
0.06
0.04
0.02
00.18
0.16
0.14
0.12
0.1
0.08
0.06
0.04
0.02
0

determined with DCCT (ordinary method)

determined with BCM (this method)

Two systems are operated.
Event Timing System and CSS archiver- operated from phase-2,- packet loss ~0.2%- cannot be operated in the injection rate >25Hz
Bucket Selection and Archiver Appliance- operated from phase-3,- Almost perfect, but still a little packet losses are found.
- possible to record all injection pulse in 50Hz

Injected current is fluctuated.
RMS ~ 0.016mADILER (mA)

Note, injection RF-bucket is changed in every
injector pulse. However, we can know it from
Bucket Selection or Event Timing System.
The measured RF-bucket is changed in every time. 6/1 22:00

6/1 22:25

Injection
loss

DILER (mA)

Damping Ring Sub-timing Station
H. Sugimura et al., “Synchronized Timing and Control System Construction ofSuperKEKB Positron Damping Ring”, in proc. ICALEPCS2017, Barcelona, Spain
EVR for injection

EVR for extraction

Optical fiber(Timing signal)

Event IOCTwo EVRs generate the injection andextraction triggers, respectively.

Optional
Extraction

The enable/disable of triggers for thekicker and septum magnets from EVGs
via the Distributed Bus Bit.
⇒ realize sophisticated DR operations
RFRTL BPM
Kicker, Septum
Optional beam extraction system- Trigger is generated with the DR revolution- Possible to extract storage beam no matter what the LINAC/DR conditions
Note, the timing trigger for the BPMs is generated by the beam diagnostic group. We skip it.

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Standalone Event Receiver (STD-EVE)
Developed by the collaboration of the KEK and SINAP control groups.

Typical VME-type EVR IOC

Standalone EVR (STD-EVE)- 1U height box on the 19inch rack
- embedded CPU with EPICS- 16 output channels with fine delay function
The easy way for install and maintain EVR

If someone want to have a new injection-trigger, he/she can set-up
and use one output channel of STD-EVE by themselves.
- Timing-expert does not need to do anything.
- Non-timing-expert of control group can work instead of them.
If someone want to install a new STD-EVE,- Timing-expert advises, but in principle, does not work anything.
- Non-timing-expert of control group can install a new STD-EVE.

They are employed also at PF-AR and ATF.

15

Year2016

MR Sub-timing Station
The STD-EVEs are installed at the D7 and D8 sub-control rooms.
Year2016

Year2019

Year2019

Standalone
EVR

The signal lines become simple and maintenance free.
- Cables are reduced.
- Many modules are removed.

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Summary
DR operation
DR Sub-timing System is developed.
- Two EVRs provide the injection and extraction timing triggers, respectively.
- It includes optional beam extraction system which works independent fromthe Event Timing System.
Beam Permission Logic and Beam Gate are upgraded.
- Three DR operation modes are included.
- The control of the injection and extraction components are realized with thedelayed synchronization.
- More frequent ON/OFF switching of Beam Gate is realized.
Improvement of accelerator drivability
Web-based monitoring system is developed.
- The infrastructure of control system is monitored.
- The system is expanded to adapt the RPC protocol of EPICS 7.
Standalone Event Receiver is developed and installed at MR.
- This system relieves the efforts of the timing experts.
New archiver systems are developed.
- EPICS Archiver Appliance is tested and seems excellent so far.
- All injection pulse data are recorded on the injection archiver.

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Upcoming Presentations
PASJ
H. Sugimura, et al., “Control system for SuperKEKB accelerator”
H. Sugimura, “Development of event receiver on Zynq evaluation board”
N. Yoshifuji, et al., “Vacuum control system based on F3RP71 for SuperKEKB”
H. Kaji, et al., “Application of EPICS Archiver Appliance at SuperKEKB”
S. Sasaki, et al., “Monitoring system with Zabbix at SuperKEKB”
T.T. Nakamura, “Application of the device configuration notation TXDB to theSuperKEKB control system”
T. Nakamura, et al., “Deployment of Archiver Appliance at PF-AR accelerator”

ICALEPCS
H. Kaji, et al., “Control System of SuperKEKB”
S. Sasaki, et al., Monitoring System for IT Infrastructure and EPICS Control
System at SuperKEKB”
T.T. Nakamura, et al., “The Upgrade Status of the SuperKEKB Magnet Control
System”
H. Sugimura, “Development of Event Receiver on Zynq7000 Evaluation
Board”

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