Alcator C-Mod Run 930611 Information

Miniproposals

Miniproposal:

Date Filed:

Title:

First Author:

Session Leader: Martin Greenwald (shots 1-25)

Operators
Session leader(s):	Martin Greenwald
Physics operator(s):	Joseph Snipes
Engineering operator(s):	Unknown

Engineering Operator Run Comment
More stable plasma sought.

Session Leader Plans

Physics Operators Plans

Session Leader Summaries

Physics Operator Summaries

Session Leader Comments

Jun 11 1993 09:00:01:260AM Joseph Snipes Trying to improve the plasma conditions.
First attempt will copy 930609023 except with fill pressure set to 4 x 10**-5
and OH2U set equal to OH2L voltage programming since the power suppplies were
fixed yesterday. Later changes will be made to the R_CUR predictor to use
Ian's predictor correcting for the offsets being programmed into the present
predictor.

Jun 11 1993 09:15:52:270AM 930611001 Martin Greenwald Plan: Try to reproduce 930609023 - Fill at 4e-5

Engineering Setup

Supply Start Close Open Crowbar Invert
EF1L -1.6 -1.55 0 .07 .35
EF1U -1.6 -1.55 0 .07 .35
OH1 -1.45 -1.4 0 .07 .35
OH2_L -1.6 -1.55 0 .07 .35
OH2_U -1.6 -1.55 0 .07 .35
EF2L -1.0 .35
EF2U -1.0 .35
EF3 -.05 .35
EF4 -1.6 .35
EFC -0.1 .30
TF -1.65 .35

Bus diags integrator -2.0 to 6.0 secs

Result: Fizzle

Jun 11 1993 09:32:21:050AM 930611001 Martin Greenwald Plan: Repeat shot 1

Result: Fizzle

Jun 11 1993 10:00:40:040AM 930611003 Martin Greenwald Plan: Repeat but fill to 6e-5
Raised EF4 current programming by 70 amps for -.2 to 0 secs
655 to 725

Changed EF3 voltage programming - point at t = zero moved 30 to 40 volts
point at zero volts moved from -.026 to
-.035

Result: Fizzle

Jun 11 1993 10:28:39:380AM 930611003 Martin Greenwald correction to last entry - fill kept at 4e-5

Jun 11 1993 10:27:09:830AM 930611004 Martin Greenwald Plan: Repeat but fill to 6e-5

Result: Fizzle

Jun 11 1993 10:43:01:920AM 930611005 Martin Greenwald Plan: Drop fill to 2.5e-5

Result: Good current trace, .28 MA, .36 seconds, but lots of runaways -
Sparks flew from limiter - no video tape!!

Jun 11 1993 10:53:44:680AM 930611006 Martin Greenwald Plan: Raise fill to 4e-5

Result: Fizzle

Jun 11 1993 11:10:56:810AM 930611007 Martin Greenwald Plan: Repeat

Result: Good Shot, Ip = .26 MA

Jun 11 1993 11:43:23:040AM 930611008 Martin Greenwald Plan: second gas puff at .8 seconds for diagnostic purposes
EF4 back from 725 to 655 amps at -.2 to 0 sec
change from Steve W. to Ian model for RCUR

Result: Good Shot, .22 MA

Jun 11 1993 11:53:43:750AM 930611009 Martin Greenwald Plan: Change RCUR program - move inside by 1 cm

Result: Same as last shot - Hits outer limiter at .07 seconds

Jun 11 1993 12:18:33:660PM 930611010 Martin Greenwald Plan: OH2L reduced at .071 sec from -70 to -45

Result: Over did OH2 change - Good plasma, but moves down too far

Jun 11 1993 12:38:24:840PM 930611011 Martin Greenwald Plan: Raised gain on RCUR feedback from .6 to .9

Result: Similar to last shot

Jun 11 1993 01:11:02:740PM 930611013 Martin Greenwald Plan: Gas puff at .8 sec changed 60 Volt
Fill pressure to 3.5e-3

Result: Similar shot

Jun 11 1993 01:32:43:400PM 930611014 Martin Greenwald Plan: Gas puff at .8 sec changed to 80 Volt
OH2 step at .071 sec moved to .12 sec and value to -40 Volts OH2L,
-50 Volts on OH2U - try to balance coils

Result: Very Similar shot - goes bad at .12! lost up and in

Jun 11 1993 01:53:57:940PM 930611015 Martin Greenwald Plan: Crowbar on OH2 from .07 to .12 (as per last shot)

Result: Vertical instability fixed - shot still disrupts at about .1sec though

Jun 11 1993 02:13:12:030PM 930611015 Martin Greenwald Plan: Offset on BSide gas to 35 volts (still at .8 secs)
Rcur derivative gain goes from .1 to .2 kept on until .5 sec
Proportional gain on until .5 sec too

Result: Still disrupts - But not as far outside as previous shot

Jun 11 1993 02:13:23:130PM 930611016 Martin Greenwald Plan: Offset on BSide gas to 35 volts (still at .8 secs)
Rcur derivative gain goes from .1 to .2 kept on until .5 sec
Proportional gain on until .5 sec too

Result: Still disrupts - But not as far outside as previous shot

Jun 11 1993 02:28:55:930PM 930611017 Martin Greenwald Plan: RCur demand to .632

Result: More or less the same as the last shot

Jun 11 1993 02:57:55:980PM 930611017 Martin Greenwald Plan: Gas dropped after .05 sec (raised slightly late .18 sec)
RCur draw to .587 m from -.12 ramps to .61 m at .08

Result: More Current, moved in about 1 cm

Jun 11 1993 03:16:06:830PM 930611019 Martin Greenwald Plan: Gas changed to Bside for fill and pulse

Result: Similar to last shot - much more ragged current pulse.
More gas, lower current

Jun 11 1993 03:21:14:920PM 930611020 Martin Greenwald Plan: Going back to B Top valve
Change RCUR controller +.02 to .015 on EF3

Result: Fizzle

Jun 11 1993 03:43:04:680PM 930611021 Martin Greenwald Plan: Repeat

Result: Good Shot

Jun 11 1993 04:00:32:700PM 930611022 Martin Greenwald Plan: Gas Program changed, shorten pulse at breakdown, then stretch out
maintenance level

Result: Fizzle

Jun 11 1993 04:18:40:900PM 930611023 Martin Greenwald Plan: Lower fill pressure to 3e-5
Rcur derivative gain up from .2 to .5

Result: Very Good Shot! .3 MA

Jun 11 1993 04:37:49:550PM 930611024 Martin Greenwald Plan: Lower (less negative) OH1 and OH2 programming after crowbar

Result: Fizzle

Jun 11 1993 05:00:02:160PM 930611025 Martin Greenwald Plan: More tweaks on OH2

Result: Never mind - runaway dominated - scads of hard xrays
arcs and sparks on the tv

Physics Operator Comments

Engineering Operator Comments

Shot Time Type Status Comment

1 09:03:24:780AM Plasma Ok 10ka plasma -- no faults

2 09:21:57:820AM Plasma Ok small flash - no faults

3 09:58:44:070AM Plasma Ok small flash -- no faults

4 10:24:08:170AM Plasma Ok 10ka plasma -- no faults,

5 10:37:59:980AM Plasma Ok 280ka

6 10:50:20:200AM Plasma Ok small flash -- no faults

7 11:06:34:370AM Plasma Ok 260ka plasma -- no faults

8 11:26:26:440AM Plasma Ok 220ka plasma -- no faults

9 11:44:51:450AM Plasma Ok 220ka plasma -- no faults

10 12:10:03:800PM Plasma Ok 260ka plasma -- no faults

11 12:29:09:590PM Plasma Ok 210ka plasma -- no faults

12 12:50:09:880PM Plasma Ok 240ka plasma -- no faults

13 01:03:52:430PM Plasma Ok 200ka plasma -- no faults

14 01:28:16:230PM Plasma Ok 260ka plasma -- no faults

15 01:42:10:510PM Plasma Ok 220ka plasma -- no faults

16 02:03:15:410PM Plasma Ok 230ka plasma -- no faults

17 02:21:15:120PM Plasma Ok 230ka plasma -- no faults

18 02:46:26:330PM Plasma Ok 280ka plasma -- no faults

19 03:05:48:080PM Plasma Ok 200ka plasma -- no faults

20 03:19:26:010PM Plasma Ok small flash, 20ka -- no faults

21 03:40:17:590PM Plasma Ok 270ka plasma -- no faults

22 03:57:52:730PM Plasma Ok 20ka plasma -- no faults

23 04:13:01:270PM Plasma Ok 300ka plasma -- no faults

24 04:33:26:460PM Plasma Ok 20ka plasma -- no faults

25 04:50:30:230PM Plasma Ok 200ka plasma

Session Leader Comments
Jun 11 1993 09:00:01:260AM		Joseph Snipes	Trying to improve the plasma conditions. First attempt will copy 930609023 except with fill pressure set to 4 x 10**-5 and OH2U set equal to OH2L voltage programming since the power suppplies were fixed yesterday. Later changes will be made to the R_CUR predictor to use Ian's predictor correcting for the offsets being programmed into the present predictor.
Jun 11 1993 09:15:52:270AM	930611001	Martin Greenwald	Plan: Try to reproduce 930609023 - Fill at 4e-5 Engineering Setup Supply Start Close Open Crowbar Invert EF1L -1.6 -1.55 0 .07 .35 EF1U -1.6 -1.55 0 .07 .35 OH1 -1.45 -1.4 0 .07 .35 OH2_L -1.6 -1.55 0 .07 .35 OH2_U -1.6 -1.55 0 .07 .35 EF2L -1.0 .35 EF2U -1.0 .35 EF3 -.05 .35 EF4 -1.6 .35 EFC -0.1 .30 TF -1.65 .35 Bus diags integrator -2.0 to 6.0 secs Result: Fizzle
Jun 11 1993 09:32:21:050AM	930611001	Martin Greenwald	Plan: Repeat shot 1 Result: Fizzle
Jun 11 1993 10:00:40:040AM	930611003	Martin Greenwald	Plan: Repeat but fill to 6e-5 Raised EF4 current programming by 70 amps for -.2 to 0 secs 655 to 725 Changed EF3 voltage programming - point at t = zero moved 30 to 40 volts point at zero volts moved from -.026 to -.035 Result: Fizzle
Jun 11 1993 10:28:39:380AM	930611003	Martin Greenwald	correction to last entry - fill kept at 4e-5
Jun 11 1993 10:27:09:830AM	930611004	Martin Greenwald	Plan: Repeat but fill to 6e-5 Result: Fizzle
Jun 11 1993 10:43:01:920AM	930611005	Martin Greenwald	Plan: Drop fill to 2.5e-5 Result: Good current trace, .28 MA, .36 seconds, but lots of runaways - Sparks flew from limiter - no video tape!!
Jun 11 1993 10:53:44:680AM	930611006	Martin Greenwald	Plan: Raise fill to 4e-5 Result: Fizzle
Jun 11 1993 11:10:56:810AM	930611007	Martin Greenwald	Plan: Repeat Result: Good Shot, Ip = .26 MA
Jun 11 1993 11:43:23:040AM	930611008	Martin Greenwald	Plan: second gas puff at .8 seconds for diagnostic purposes EF4 back from 725 to 655 amps at -.2 to 0 sec change from Steve W. to Ian model for RCUR Result: Good Shot, .22 MA
Jun 11 1993 11:53:43:750AM	930611009	Martin Greenwald	Plan: Change RCUR program - move inside by 1 cm Result: Same as last shot - Hits outer limiter at .07 seconds
Jun 11 1993 12:18:33:660PM	930611010	Martin Greenwald	Plan: OH2L reduced at .071 sec from -70 to -45 Result: Over did OH2 change - Good plasma, but moves down too far
Jun 11 1993 12:38:24:840PM	930611011	Martin Greenwald	Plan: Raised gain on RCUR feedback from .6 to .9 Result: Similar to last shot
Jun 11 1993 01:11:02:740PM	930611013	Martin Greenwald	Plan: Gas puff at .8 sec changed 60 Volt Fill pressure to 3.5e-3 Result: Similar shot
Jun 11 1993 01:32:43:400PM	930611014	Martin Greenwald	Plan: Gas puff at .8 sec changed to 80 Volt OH2 step at .071 sec moved to .12 sec and value to -40 Volts OH2L, -50 Volts on OH2U - try to balance coils Result: Very Similar shot - goes bad at .12! lost up and in
Jun 11 1993 01:53:57:940PM	930611015	Martin Greenwald	Plan: Crowbar on OH2 from .07 to .12 (as per last shot) Result: Vertical instability fixed - shot still disrupts at about .1sec though
Jun 11 1993 02:13:12:030PM	930611015	Martin Greenwald	Plan: Offset on BSide gas to 35 volts (still at .8 secs) Rcur derivative gain goes from .1 to .2 kept on until .5 sec Proportional gain on until .5 sec too Result: Still disrupts - But not as far outside as previous shot
Jun 11 1993 02:13:23:130PM	930611016	Martin Greenwald	Plan: Offset on BSide gas to 35 volts (still at .8 secs) Rcur derivative gain goes from .1 to .2 kept on until .5 sec Proportional gain on until .5 sec too Result: Still disrupts - But not as far outside as previous shot
Jun 11 1993 02:28:55:930PM	930611017	Martin Greenwald	Plan: RCur demand to .632 Result: More or less the same as the last shot
Jun 11 1993 02:57:55:980PM	930611017	Martin Greenwald	Plan: Gas dropped after .05 sec (raised slightly late .18 sec) RCur draw to .587 m from -.12 ramps to .61 m at .08 Result: More Current, moved in about 1 cm
Jun 11 1993 03:16:06:830PM	930611019	Martin Greenwald	Plan: Gas changed to Bside for fill and pulse Result: Similar to last shot - much more ragged current pulse. More gas, lower current
Jun 11 1993 03:21:14:920PM	930611020	Martin Greenwald	Plan: Going back to B Top valve Change RCUR controller +.02 to .015 on EF3 Result: Fizzle
Jun 11 1993 03:43:04:680PM	930611021	Martin Greenwald	Plan: Repeat Result: Good Shot
Jun 11 1993 04:00:32:700PM	930611022	Martin Greenwald	Plan: Gas Program changed, shorten pulse at breakdown, then stretch out maintenance level Result: Fizzle
Jun 11 1993 04:18:40:900PM	930611023	Martin Greenwald	Plan: Lower fill pressure to 3e-5 Rcur derivative gain up from .2 to .5 Result: Very Good Shot! .3 MA
Jun 11 1993 04:37:49:550PM	930611024	Martin Greenwald	Plan: Lower (less negative) OH1 and OH2 programming after crowbar Result: Fizzle
Jun 11 1993 05:00:02:160PM	930611025	Martin Greenwald	Plan: More tweaks on OH2 Result: Never mind - runaway dominated - scads of hard xrays arcs and sparks on the tv

Engineering Operator Comments
Shot	Time	Type	Status	Comment
1	09:03:24:780AM	Plasma	Ok	10ka plasma -- no faults
2	09:21:57:820AM	Plasma	Ok	small flash - no faults
3	09:58:44:070AM	Plasma	Ok	small flash -- no faults
4	10:24:08:170AM	Plasma	Ok	10ka plasma -- no faults,
5	10:37:59:980AM	Plasma	Ok	280ka
6	10:50:20:200AM	Plasma	Ok	small flash -- no faults
7	11:06:34:370AM	Plasma	Ok	260ka plasma -- no faults
8	11:26:26:440AM	Plasma	Ok	220ka plasma -- no faults
9	11:44:51:450AM	Plasma	Ok	220ka plasma -- no faults
10	12:10:03:800PM	Plasma	Ok	260ka plasma -- no faults
11	12:29:09:590PM	Plasma	Ok	210ka plasma -- no faults
12	12:50:09:880PM	Plasma	Ok	240ka plasma -- no faults
13	01:03:52:430PM	Plasma	Ok	200ka plasma -- no faults
14	01:28:16:230PM	Plasma	Ok	260ka plasma -- no faults
15	01:42:10:510PM	Plasma	Ok	220ka plasma -- no faults
16	02:03:15:410PM	Plasma	Ok	230ka plasma -- no faults
17	02:21:15:120PM	Plasma	Ok	230ka plasma -- no faults
18	02:46:26:330PM	Plasma	Ok	280ka plasma -- no faults
19	03:05:48:080PM	Plasma	Ok	200ka plasma -- no faults
20	03:19:26:010PM	Plasma	Ok	small flash, 20ka -- no faults
21	03:40:17:590PM	Plasma	Ok	270ka plasma -- no faults
22	03:57:52:730PM	Plasma	Ok	20ka plasma -- no faults
23	04:13:01:270PM	Plasma	Ok	300ka plasma -- no faults
24	04:33:26:460PM	Plasma	Ok	20ka plasma -- no faults
25	04:50:30:230PM	Plasma	Ok	200ka plasma