Magnets_&_QPS_towards_operation
Download
Report
Transcript Magnets_&_QPS_towards_operation
Magnets & QPS towards operation. N. Catalan Lasheras
Magnets & QPS towards operation
N. Catalan Lasheras on behalf of MPP and QPS teams
LTC extended meeting 3 March 2008
1
OUTLINE
How to operate up to 8 sectors together?
How do we operate during the hardware commissioning
Recovery after a quench: how much time does it take? Is expert
intervention required? How can this be improved?
Magnets & QPS towards operation. N. Catalan Lasheras
Equipment folder: tests results, handling of non-conformities,
performance below specs, machine as commissioned vs. machine
as nominal
How will we operate after hardware commissioning
Alarms/signals/SW available in CCC
Piquet/Experts availability
How to operate up to 8 sectors together
2
How does it work during hardware commissioning
Procedures for the powering tests are defined/revised by MPP, QPS, PO, CO
A series of tests at different currents checking the full functionality of all
systems
From each test we may extract and store data (in MTF)
Magnets & QPS towards operation. N. Catalan Lasheras
Each test is approved by at least an expert group (PO, QPS, PIC or MPP)
In CCC an automatic software operated by the EiC runs the tests as defined
by the hardware commissioning coordinator.
The circuit is commissioned at the end of the tests and released for powering
after the off-line analysis has been done
3
How does it work during hardware commissioning
A QPS team is formed by two operators and a
team leader. Can ensure two fronts
simultaneously.
Four QPS teams in the CCC. Two shifts. Four
fronts. Backed up by 4-5 coordinators.
Magnets & QPS towards operation. N. Catalan Lasheras
Staffing is not assured from May
Two MPP (magnet performance panel) experts
in the CCC for all fronts. Manpower may become
critical with several sectors.
An energy extraction (EE) field team supervising
part of the tests.
Teams on call to diagnose electrical faults.
4
Recovery after a quench (I) . Energy extraction
Dipole dump resistor temp and cooling time.
300
140
Temp
Magnets & QPS towards operation. N. Catalan Lasheras
Temp [C]
Series4
100
200
80
150
60
100
Quadrupole threshold
50
40
Dipole threshold
Cooling time [min]
120
250
20
0
0
0
2
4
6
8
10
12
14
kA
In case of a quench always in the shadow of cryogenics recovery
In case of extraction for other reasons (e.g. FPA request) the
minimum recovery time will be determined by the DQR cooling
5
Recovery after a quench (II). Analysis
Analysis after a quench
– Heater discharged ok?
– Energy extraction ok?
Quench origin
Magnets & QPS towards operation. N. Catalan Lasheras
– Magnets, current leads, bus bar
– PC or QPS trigger
Very fast quench propagation, requench.
– New phenomena not observed in
SM18 or in the string.
– Not understood yet.
– More may come
6
Manufacturing test folders
The sequencers fills automatically the MTF steps and sends the data taken
on-line
Non conformities are open off-line
Off-line data is entered after analysis
Magnets & QPS towards operation. N. Catalan Lasheras
After all steps are finished, analysed and ok, the circuit is released for
operation
Still working on sector 4-5...
7
Non-conformities
All NC opened in EDMS and attached to circuits
Magnets & QPS towards operation. N. Catalan Lasheras
NC in a sector opened during HW are accessible from the HC page
When the circuit can not be powered, the leads are grounded and the PC
not connected or condemned
When the circuit can only be powered up to a level of current, hardware and
software limited
8
How to avoid powering above the allowed limits?
Circuits in LHC will be
commissioned to what is called
I_PNO.
700
120
600
100
This current is a parameter that
Magnets & QPS towards operation. N. Catalan Lasheras
may be different from the LHC
design report.
How to prevent accidental
powering above this current?
500
80
400
60
Hardware and software limits can
300
be set in the power converter.
40
6 KA and 13 kA converters can be
limited at any value
May be wise to use these values
when defining I_PNO
200
20
100
0
0
RPLA
RPLB
RPMBA/B
RPMC
9
Magnets & QPS towards operation. N. Catalan Lasheras
Review of the powering procedures
We are not repeating the same tests for different energies...not very
efficient...
Each functionality of the system is tested only once at the optimum current
level.
A circuit is commissioned only after tests called PNO are done successfully.
We can shorten PNO by decreasing the energy (avoiding quenches and
testing with degraded cryogenic conditions) but not by cutting tests.
10
QPS in operational mode
QPS will re-arm automatically after a quench as well the DAQ for the EE
(feature already enabled for individual MB and MQ protection, under test for
the rest)
Magnets & QPS towards operation. N. Catalan Lasheras
EE systems can be closed via macros allowing to close all switches of a
sector or all of the LHC. AB-CO promised to have this feature available for
sector 5-6.
Expert intervention only required in case of faults. The system can be
controlled by the LHC operator entirely via the PVSS supervision using a
restricted (=safe) command set.
The POWER_PERMIT status of each circuit is transmitted to LASER (not
enabled for commissioning). Supervision will allow then to identify the
element of the circuit provoking the alarm
– RED = quench/activation of EE system,
– GREEN = logging mode = fully operational,
– ORANGE = POWER_PERMIT lost.
11
Magnets in operational mode
Analysis of the QPS and EE systems after a quench could be automatic or
assisted by defining tolerances.
– Heater discharge voltage time constant and minimum value.
– Extraction resistor voltage maximum value and time constant.
Magnets & QPS towards operation. N. Catalan Lasheras
Trips of the PC can be diagnosed using the PVSS system
Some analysis still needed
– Trip of the QPS system
– Origin of the quench
– Quench propagation
Magnets trained to “nominal current” are not expected to undergo training
quenches. Any quench is then exceptional.
12
Software available
PVSS supervision.
Post mortem analysis.
TIMBER.
Magnets & QPS towards operation. N. Catalan Lasheras
Analysis software
– Currently used for analysis of hardware commissioning tests. Not
always useful for operation
– Set of expert analysis tools currently under construction. Always based
in PMS and Timber.
– EiC aware and knowledgeable.
– Availability and suitability to be decided.
AB/CO writes and maintains the software.
13
Piquet service
A piquet service is being discussed as of this month
It could regroup the experts from
– QPS Quench protection and energy extraction
– ElQA electrical quality assurance, diagnostics and repairs
Magnets & QPS towards operation. N. Catalan Lasheras
– Current leads, disconnection and re-connection.
Training on the other functions will be done during hardware commissioning
Start of the piquet service only after hardware commissioning if requested.
MPP and QPS experts will be available in the CCC until the end of
commissioning. Two shifts.
Assistance of MPP for quench analysis and recovery during beam
commissioning and beyond is being discussed within the AT department.
14
Magnets & QPS towards operation. N. Catalan Lasheras
How to run all 8 sectors together
After commissioning of the circuits, functionality and availability are
guaranteed. Few events expected.
Very successful run during PGC tests in sector 4-5!
Question should be addressed to CO and OP?
15
Conclusions
Hardware commissioning still ongoing. We do not have all the answers yet.
After the circuits are commissioned few events are expected.
Magnets & QPS towards operation. N. Catalan Lasheras
Recovery from a quench should be automatic. The time to recover can be
estimated very accurately.
Supervision software will indicate the faulty circuit/system. PMA and Timber
can be used for analysis.
Experts will be in CCC till the end of hardware commissioning. Some
experts will be required in beam commissioning and beyond.
All non-conformities in MTF and visible trough different tools.
Circuits should be locked to commissioned currents.
Powering of a group of circuits is the first step trough operating LHC.
Thanks: K. Dahlerup Petersen, R. Denz, S. Le Naour, A. Siemko, Y.
Thurel, L. Walckiers
16
Post-Mortem Analysis
One file per event per system and per
Magnets & QPS towards operation. N. Catalan Lasheras
subsystem with the time stamp
17
Magnets & QPS towards operation. N. Catalan Lasheras
PVSS supervision
18
Timber
Continuous loogging of data for all
Magnets & QPS towards operation. N. Catalan Lasheras
systems (slower rate).
19