Alcator C-Mod Run 1001207 Information

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Miniproposals
Miniproposal:268
Date Filed: 4/7/2000
Title:Conditioning of D-, E-, or J-Port ICRF Antenna
First Author:Gerd Schilling
Session Leader:Rejean Boivin (shots 1-17)
Session Leader:Steve Wukitch (shots 1-17)

Operators
Session leader(s):Rejean Boivin,Steve Wukitch
Physics operator(s):Bill Rowan
Engineering operator(s):Bill Parkin,Gary Dekow

Engineering Operator Run Comment
MP 268 RF Conditioning Sl: Wukitch/Boivin PO: Rowan EO: Dekow/Parkin

Session Leader Plans

Physics Operators Plans

Session Leader Summaries
Entered: Jul 7 2004 03:49:25:993PM
Author: To Be Determined
Engineering setup and run plan for Thursday 07 Dec 2000.

MP #268 RF conditioning

Session leaders: Wukitch/Boivin
Physics operator: Rowan

-------------------------------------------------------------------------------
Engineering setup:

ECDC in D2 for 2 hours before the run.

Power systems as on 1001206010.

Gas setup:
fill B-top with 6 psi of D2 Hybrid enabled
fill B-side lower with 1 psi of Ar Hybrid DISABLED
fill B-side upper with 35 psi of D2 Hybrid DISABLED, for ECDC
fill C-side with 30 psi of D2 Hybrid enabled
leave J-bot as is Hybrid DISABLED

Enable the following gate valves: ECE, VUV, Beast, DNB

Run starts at 09:00 and ends at 17:00.

-------------------------------------------------------------------------------

RF Setup:

XMTRs 1,2,3, and 4 should be made ready by 8:00 (run-on).

-------------------------------------------------------------------------------

Run Plan:

Further tests of J-port performance as a four-strap.

Re-load a late shot from yesterday (0.8 MA, 5.3 T, NL_ZMETER). Fire
J-port into plasma. During the day we may raise the density, and if
everything works well, we may eventually the current.

-------------------------------------------------------------------------------

001

request: 5.2 T, Ip=0.8 MA, nl_04~1e20
J= 1 MW [0.6,1.4] sec

result: plasma
max faults from #4

next shot: retune and try again

002

request: 5.2 T, Ip=0.8 MA, nl_04~1e20
J= 1 MW [0.6,1.4] sec

result: plasma
max faults from #4

next shot: retune and try again

003
request: 5.2 T, Ip=0.8 MA, nl_04~1e20
J= 1 MW [0.6,1.4] sec

result: plasma
max faults from #4

next shot:

004
request: 5.2 T, Ip=0.8 MA, nl_04~1e20
J= 1 MW [0.6,1.4] sec

result: plasma
max faults from #4 but ran longer
reflected power suddenly jumps at 0.615 sec on #4
does not disappear with higher power - glow

next shot: turn on harder (<1 msec)

005

request: 5.2 T, Ip=0.8 MA, nl_04~1e20
J= 1 MW [0.6,1.4] sec

result: plasma - early disruption 0.86 sec
J4 max faulted again
appears that the phase feedback is oscillating!?
appears that the DC2 calibration factor is off since 003

break to vacuum test phase feedback and #4 phase shifter/stub tuner

Found J3 and J4 vacuum tunes [st,ps]:
J3: [424,375] compared to [441,385]
J4: [435,147] compared to [435,635]

There appears to be some coupling between J3 and J4.

+ conditioned up to 100 kW (~22 kV)
+ phase feedback appears to be working and responding

+tested the range on #4 ST/PS set and found good agreement with
recorded limits.

-- found that to go from +0.2 pi to 0 pi needed to change from 50 deg
to 95 deg -- antenna phase relationship


006
request: 5.2 T, Ip=0.8 MA, nl_04~1e20
J= 1 MW [0.6,1.4] sec

result: fizzle

007

request: 5.2 T, Ip=0.8 MA, nl_04~1e20
J= 1 MW [0.6,1.4] sec

result: plasma
J3 0.6 MW, 3 faults
J4 0.6 MW, max faults by end of pulse - much improved

+ phase was -0.2pi between 2-3 (needs to be 0)
reduce from 77 deg to 50 deg for next shot

008

request: 5.2 T, Ip=0.8 MA, nl_04~1e20
J= ramp to 2 MW [0.6,1.4] sec

result: plasma
J3 0.95 MW, 3 faults
J4 0.9 MW, max faults by end of pulse - much improved

+ phase was -0.2pi between 2-3 at a phase setting of 50 deg.

009

request: 5.2 T, Ip=0.8 MA, nl_04~1e20
J= ramp to 2 MW [0.6,1.4] sec

result: plasma
J3 0.95 MW, 6 faults
J4 0.9 MW, 6 faults

+ phase was -0.2pi between 2-3 at a phase setting of 50 deg.

010

request: 5.2 T, Ip=0.8 MA, nl_04~1e20
J= ramp to 2 MW [0.6,1.4] sec

result: plasma, H-mode, disrupted ~1.32 sec
J3 1.0 MW, 6 faults
J4 1.1 MW, 6 faults

011

request: 5.2 T, Ip=0.8 MA, nl_04~1e20
J= ramp to 2 MW [0.6,1.4] sec

result: plasma
changed upper triangularity from 0.4 to 0.25
J3 MW, max faults
J4 MW, max faults
upper antenna tiles are very bright

012

request: 5.2 T, Ip=0.8 MA, nl_04~1e20
J= ramp to 2 MW [0.6,1.4] sec

result: plasma
changed upper triangularity from 0.4 to 0.25
J3 MW, max faults
J4 MW, max faults
upper antenna tiles are very bright - efit suggests we are
rubbing the plasma against the antenna protection tiles
013

request: 5.2 T, Ip=0.8 MA, nl_04~1e20
J= ramp to 2 MW [0.6,1.4] sec

result: plasma
J3 1.15 MW, max faults by end
J4 1.3 MW, one fault

next shot: try short high power pulse at start of RF

014

request: 5.2 T, Ip=0.8 MA, nl_04~1e20
J= ramp to 3.5 MW [0.6,1.4] sec

result: plasma
J3 1.6 MW, max faults by end
J4 1.7 MW, one fault

Having injections from top front tiles like we had with E-port
Is the high neutral pressure the problem?

015

request: 5.2 T, Ip=0.8 MA, nl_04~1e20
J= ramp to 3.0 MW [0.6,1.4] sec

result: plasma, early disruption - injections from antenna
J3 1.5 MW, 5 faults
J4 1.5 MW, 4 faults

016

request: 5.2 T, Ip=0.8 MA, nl_04~1e20
J= ramp to 2.5 MW [0.6,1.4] sec

result: plasma, H-modes early disruption - injections from antenna
J3 1.2 MW, 3 faults
J4 1.3 MW, 3 faults

017

request: 5.2 T, Ip=0.8 MA, nl_04~1e20
J= ramp to 2.5 MW [0.6,1.4] sec

result: plasma
J3 1.2 MW, 3 faults
J4 1.3 MW, 3 faults

Summary:

We spent time yesterday afternoon and this morning trying to eliminate
the RF interference in the EF1 upper and lower. Further dummy load
tests suggest that FMIT#3 has significant RF leakage that was
difficult to fix. During test shots we were able to reduce the
"induced" current by ~2, but appeared to be less effective during
machine operation. Significant time was required to recondition the
antenna so it would operate without max faults in the first 100 msec.
There was evidence of a problem between the shorted end of the antenna
and the voltage probes. A sudden increase in reflected power was seen
on shot 005 and the voltage phase was different from the expected
value. After conditioning the antenna in vacuum to 100 kW, the
antenna began operating in plasma. There was significant visible
light at the K-side upper corner of the antenna and over the strap
centers between the BN and Mo tiles for RF power levels above 2 MW.
The former may be the same interaction observed in October and the
latter may be similar to the interaction observed with E-port when
operated at high neutral pressure. We need to investigate effect of
current and density on the observed phenomena.

Physics Operator Summaries
Entered: Jul 7 2004 04:37:12:800PM
Author: To Be Determined
PhysOp Summary for 1001207

Experiment
--------------------------
MP #268 RF conditioning
Session leaders: Wukitch/Boivin

Physics operator: Rowan

Engineering operator: Dekow

Engineering setup
--------------------------
ECDC in D2 for 2 hours before the run.

Power systems as on 1001206010.

Gas setup:
fill B-top with 6 psi of D2 Hybrid enabled
fill B-side lower with 1 psi of Ar Hybrid DISABLED
fill B-side upper with 35 psi of D2 Hybrid DISABLED, for ECDC
fill C-side with 30 psi of D2 Hybrid enabled
leave J-bot as is Hybrid DISABLED

Enable the following gate valves: ECE, VUV, Beast, DNB

RF Setup:

XMTRs 1,2,3, and 4 should be made ready by 8:00 (run-on).

Run Plan
----------------------------

Further tests of J-port performance as a four-strap.
Re-load a late shot from yesterday (0.8 MA, 5.3 T, NL_ZMETER). Fire J-port
into plasma. During the day we may raise the density, and if everything
works well, we may eventually the current.


Summary
---------------------------
Spanna crashed just before the start of the run. After a reboot, there were no
further problems.

From an operations point of view, the run was relatively uneventful. The
disruptions were RF related. The single fizzle occurred after a period of RF
vacuum conditioning and may too have been RF related.

There was an attempt to change the upper x-point. Brian suggested this as a
means for reducing the midplane pressure. Desirable for RF and for DNB.
The x-point did move. The midplane pressure was unaffected. This was quickly
abandoned as the change in configuration led to hitting the current limit on EF1_U

Score Card
---------------------------
Tests 0
Duds 0
Fizzles 1
Disruptions 4
Plasmas 12
----------------
Total 17


Details of the run
--------------------------
001. Plasma. Full length. Disrupted during the ramp down at 1.8 s.
Breakdown looks okay -- does not have the slight hesitation in the current rise
observed for the reference shot
Pressure at breakdown is 0.06 mT. No problems from DNB which opened
on this shot.
BR and BZ at t=0 are identical to the reference shot

002. Plasma.

003. Plasma.Turned on Argon for Rice/Rotation

004. Plasma.

005. Plasma. Disruption at 0.8 s.
Increased Ar for Rice/Rotation. Ar not the cause of disruption.

006. Fizzle
Pressure is slightly lower. BZ and BR are unchanged from the reference shot or
from the previous shot.
There was a pause of about an hour before this shot. During that time, there was
RF vacuum conditioning which may have induced the fizzle.

007. Plasma.

008. Plasma.

009. Plasma

010. Plasma. Disrupted at 1.3 s

011. Plasma.
Attempted to move RXU out by 5 cm. ZXU up by 5 cm. Recommended by Brain to reduce
the midplane pressure. ZXU responded as intended. RXU was moved too far.
The midplane pressure was not reduced.

012. Plasma.
Some correction applied to RXU but noticed that EF1_U was at its current limit.

013. Plasma
Reverted to shot 009

014. Plasma

015. Plasma. Disruption at t=0.88

016. Plasma. Disruption at 1 s.

017. Plasma. Disruption at 1.2 s.

Session Leader Comments
Dec 7 2000 09:37:47:873AM1001207001Steve Wukitch001

request: 5.2 T, Ip=0.8 MA, nl_04~1e20
J= 1 MW [0.6,1.4] sec

result: plasma
max faults from #4

next shot: retune and try again
Dec 8 2000 10:45:40:123AM1001207001Steve Wukitch001

request: reload 1001207017
BT=5.2 T, Ip=0.8 MA, nl_04~1e20 m^-2
J ramp to 1 MW [.6,1.4] sec

result: plasma
J3: 0.5 MW 3 faults
J4: 0.5 MW 3 faults
+ reflected power spikes observed on pci data (200 kHz) #3 and #4

Dec 7 2000 09:50:33:717AM1001207002Steve Wukitch002

request: 5.2 T, Ip=0.8 MA, nl_04~1e20
J= 1 MW [0.6,1.4] sec

result: plasma
max faults from #4

next shot: retune and try again
Dec 7 2000 12:57:14:483PM1001207003Steve Wukitch003
request: 5.2 T, Ip=0.8 MA, nl_04~1e20
J= 1 MW [0.6,1.4] sec

result: plasma
max faults from #4
Dec 7 2000 12:57:32:750PM1001207004Steve Wukitch004
request: 5.2 T, Ip=0.8 MA, nl_04~1e20
J= 1 MW [0.6,1.4] sec

result: plasma
max faults from #4 but ran longer
reflected power suddenly jumps at 0.615 sec on #4
does not disappear with higher power - glow

next shot: turn on harder (<1 msec)
Dec 7 2000 12:58:34:763PM1001207005Steve Wukitch005

request: 5.2 T, Ip=0.8 MA, nl_04~1e20
J= 1 MW [0.6,1.4] sec

result: plasma - early disruption 0.86 sec
J4 max faulted again
appears that the phase feedback is oscillating!?
appears that the DC2 calibration factor is off since 003
Dec 7 2000 12:58:53:357PM1001207006Steve Wukitch006
request: 5.2 T, Ip=0.8 MA, nl_04~1e20
J= 1 MW [0.6,1.4] sec

result: fizzle

Dec 7 2000 01:28:41:310PM1001207007Steve Wukitch007

request: 5.2 T, Ip=0.8 MA, nl_04~1e20
J= 1 MW [0.6,1.4] sec

result: plasma
J3 0.6 MW, 3 faults
J4 0.6 MW, max faults by end of pulse - much improved

+ phase was -0.2pi between 2-3 (needs to be 0)
reduce from 77 deg to 50 deg for next shot
Dec 7 2000 01:40:26:560PM1001207008Steve Wukitch008

request: 5.2 T, Ip=0.8 MA, nl_04~1e20
J= ramp to 2 MW [0.6,1.4] sec

result: plasma
J3 0.95 MW, 3 faults
J4 0.9 MW, max faults by end of pulse - still improving

+ phase was -0.2pi between 2-3 at a phase setting of 50 deg.
Dec 7 2000 01:59:50:530PM1001207009Steve Wukitch009

request: 5.2 T, Ip=0.8 MA, nl_04~1e20
J= ramp to 2 MW [0.6,1.4] sec

result: plasma
J3 0.95 MW, 6 faults
J4 0.9 MW, 6 faults

next shot: raise power to 1.2 MW
Dec 7 2000 03:08:30:357PM1001207010Steve Wukitch010

request: 5.2 T, Ip=0.8 MA, nl_04~1e20
J= ramp to 2 MW [0.6,1.4] sec

result: plasma, H-mode, disrupted ~1.32 sec
J3 1.0 MW, 6 faults
J4 1.1 MW, 6 faults
Dec 7 2000 03:14:00:670PM1001207011Steve Wukitch011

request: 5.2 T, Ip=0.8 MA, nl_04~1e20
J= ramp to 2 MW [0.6,1.4] sec

result: plasma
changed upper triangularity from 0.4 to 0.25
J3 MW, max faults
J4 MW, max faults
upper antenna tiles are very bright
Dec 7 2000 03:14:44:530PM1001207012Steve Wukitch012

request: 5.2 T, Ip=0.8 MA, nl_04~1e20
J= ramp to 2 MW [0.6,1.4] sec

result: plasma
changed upper triangularity from 0.4 to 0.25
J3 MW, max faults
J4 MW, max faults
upper antenna tiles are very bright - efit suggests we are
rubbing the plasma against the antenna protection tiles

raise upper triangularity to 010 value of 0.4
Dec 7 2000 04:10:39:607PM1001207013Steve Wukitch013

request: 5.2 T, Ip=0.8 MA, nl_04~1e20
J= ramp to 2 MW [0.6,1.4] sec

result: plasma
J3 1.15 MW, max faults by end
J4 1.3 MW, one fault

next shot: try short high power pulse at start of RF
Dec 7 2000 04:10:58:530PM1001207014Steve Wukitch014

request: 5.2 T, Ip=0.8 MA, nl_04~1e20
J= ramp to 3.5 MW [0.6,1.4] sec

result: plasma
J3 1.6 MW, max faults by end
J4 1.7 MW, one fault

Having injections from top front tiles like we had with E-port
Is the high neutral pressure the problem?

Dec 8 2000 09:24:57:623AM1001207015Steve Wukitch015

request: 5.2 T, Ip=0.8 MA, nl_04~1e20
J= ramp to 3.0 MW [0.6,1.4] sec

result: plasma, early disruption - injections from antenna
J3 1.5 MW, 5 faults
J4 1.5 MW, 4 faults
Dec 8 2000 09:30:37:780AM1001207016Steve Wukitch016

request: 5.2 T, Ip=0.8 MA, nl_04~1e20
J= ramp to 2.5 MW [0.6,1.4] sec

result: plasma, H-modes early disruption - injections from antenna
J3 1.2 MW, 3 faults
J4 1.3 MW, 3 faults
Dec 8 2000 10:44:57:217AM1001207017Steve Wukitch017

request: 5.2 T, Ip=0.8 MA, nl_04~1e20
J= ramp to 2.5 MW [0.6,1.4] sec

result: plasma
J3 1.2 MW, 3 faults
J4 1.3 MW, 3 faults

Physics Operator Comments
Dec 7 2000 08:24:56:607AMBill RowanEngineering setup and run plan for Thursday 07 Dec 2000.

MP #268 RF conditioning

Session leaders: Wukitch/Boivin
Physics operator: Rowan

-------------------------------------------------------------------------------
Engineering setup:

ECDC in D2 for 2 hours before the run.

Power systems as on 1001206010.

Gas setup:
fill B-top with 6 psi of D2 Hybrid enabled
fill B-side lower with 1 psi of Ar Hybrid DISABLED
fill B-side upper with 35 psi of D2 Hybrid DISABLED, for ECDC
fill C-side with 30 psi of D2 Hybrid enabled
leave J-bot as is Hybrid DISABLED

Enable the following gate valves: ECE, VUV, Beast, DNB

Run starts at 09:00 and ends at 17:00.

-------------------------------------------------------------------------------

RF Setup:

XMTRs 1,2,3, and 4 should be made ready by 8:00 (run-on).

-------------------------------------------------------------------------------

Run Plan:

Further tests of J-port performance as a four-strap.
Re-load a late shot from yesterday (0.8 MA, 5.3 T, NL_ZMETER). Fire J-port
into plasma. During the day we may raise the density, and if everything
works well, we may eventually the current.

Dec 7 2000 08:44:52:610AMBill RowanStarted PCS
Loaded shot from 1001206010
Load/Clean with this result
Load at 7-Dec-2000 08:32:30.00

Did a cold start
7-DEC-2000 08:36:30.15 doing TCL
*************** END COLDSTART ******************
Dec 7 2000 09:13:59:983AMBill RowanSPANNA crashed.
Reloaded shot 1001206010
Load/Clean
Dec 7 2000 09:32:33:967AM1001207001Bill Rowanoo1. Plasma. Full length. Disrupted during the ramp down at 1.8 s.
Breakdown looks okay -- does not have the slight hesitation in the current rise
observed for the reference shot
Pressure at breakdown is 0.06 mT. No problems from DNB which opened
on this shot.
BR and BZ at t=0 are identical to the reference shot
Dec 7 2000 09:37:16:590AM1001207001Bill Rowan

Next shot. No changes
Dec 7 2000 09:51:46:340AM1001207002Bill Rowan002. Plasma. As previous shot.

Next shot. Turned Argon on for Rotation/Rice
Dec 7 2000 10:05:46:670AM1001207003Bill Rowan003. Plasma . As previous shot.
Dec 7 2000 10:24:53:797AM1001207003Bill Rowan003. Plasma . As previous shot.

Next shot. No changes
Dec 7 2000 10:35:30:687AM1001207004Bill Rowan004. Plasma. As previous shot.

Dec 7 2000 10:47:16:920AM1001207004Bill RowanNext shot. Increased the Argon pulse by 4 ms at request of rotation rice
Dec 7 2000 11:05:11:750AM1001207005Bill Rowan005. Plasma. Disruption at 0.8 s
Dec 7 2000 11:27:33:890AM1001207005Bill Rowan
Pause after this shot for RF.
Dec 7 2000 12:39:15:827PM1001207005Bill Rowan


Next shot. No changes.
Dec 7 2000 12:55:09:357PM1001207006Bill Rowan006. Fizzle
Dec 7 2000 01:00:08:500PM1001207006Bill Rowan

Next shot. Add 1 ms to the prefill
Dec 7 2000 01:11:58:890PM1001207007Bill Rowan007. Plasma. Similar to 005

Dec 7 2000 01:16:16:687PM1001207007Bill Rowan
Next shot: No changes
Dec 7 2000 01:34:17:967PM1001207008Bill Rowan008. Plasma.
Dec 7 2000 01:40:36:843PM1001207008Bill Rowan008. Plasma.

Next shot. No changes.
Dec 7 2000 02:05:18:437PM1001207009Bill Rowan009. Plasma

Next shot: no changes

Dec 7 2000 02:48:04:043PM1001207011Bill Rowan011. Plasma.
ZXU is as intended. RXU was moved too far.

Next shot: Mode RXU in by 2 cm.
Dec 7 2000 03:08:35:937PM1001207012Bill Rowan012. Plasma
Current limit on EF1_U

Next shot: Reverted to 009.
Dec 7 2000 03:41:46:997PM1001207013Bill Rowan013. Plasma

Next shot: No changes
Dec 7 2000 04:02:42:623PM1001207014Bill Rowan014. Plasma

Next shot: No changes
Dec 7 2000 04:29:20:483PM1001207015Bill Rowan015. Plasma. Disruption at t=0.88 s

Next shot: No changes
Dec 7 2000 04:50:22:123PM1001207016Bill Rowan016. Plasma Disruption at 1 s
Next shot. No changes
Dec 7 2000 05:01:35:653PM1001207017Bill Rowan017. Plasma. Disruption at 1.2 s.

Engineering Operator Comments
ShotTimeTypeStatusComment
109:22:44:450AMPlasmaOk
209:39:34:810AMPlasmaOk
309:59:32:000AMPlasmaOk
410:25:34:200AMPlasmaOk
510:49:33:013AMPlasmaOk
612:47:14:717PMPlasmaOk
701:03:12:200PMPlasmaOk
801:28:27:997PMPlasmaOk
901:50:33:700PMPlasmaOk
1002:14:45:200PMPlasmaOk
1102:37:46:030PMPlasmaOk
1203:01:19:327PMPlasmaOk
1303:25:39:543PMPlasmaOk
1403:48:41:920PMPlasmaOk
1504:11:57:170PMPlasmaOk
1604:34:11:450PMPlasmaOk
1704:58:32:200PMPlasmaOk