Miniproposals

Miniproposal: 040 Date Filed: 4/4/1994 Title: Checking vertical alignment of ECE First Author: Amanda Hubbard Session Leader: Amanda Hubbard (shots 1-25)

Engineering Operator Run Comment

ece align

Session Leader Plans

Physics Operators Plans

Session Leader Summaries

Physics Operator Summaries

Entered: Jul 7 2004 04:36:52:083PM

Author: To Be Determined

Physics operator summary for 941201 EO: Bertilino/Gwinn PO: Goetz SL: Hubbard Run 941121 was in support of Mini-Proposal #040 - ECE Alignment This proposal calls for a series of stable, reproducible shots for alignment of the ECE beamline (and check-out of various other diagnostics). To this end, shot 941130033 was loaded into the hybrid. This was a shot that had an acceptable equilbrium at 0.3 sec. Using the new orthogonal shape controllers, try and hold this equilibrium for the rest of the shot. Today's goals were to try to obtain constant shots suitable for diagnostic checkout and determine if the new orthogonal shape controllers will work for a limited, moderate elongation plasma. These goals were accomplished. Constant shots were obtained for ECE alignment and HIREX troubleshooting. The new orthogonal shape controllers do indeed work for limiter plasmas centered on the midplane with a kappa of 1.4. Some things discovered today: 1) The thrash in RCUR at .1s is caused by the difference in offsets between the two segments. Notching the D gain and lowering the P gain across the segment switch kept the control from over-correcting and throwing the plasma into the outboard limiter. A gap of >.01 was maintained with a notch of .01 sec. 2) The disruptions during rampdown at ~.2MA are more than likely caused by 'shark fins'. This condition was avoided by slowing the rampdown rate of the plasma current, which together with the lower density (achieved just by waiting longer) allowed these plasmas to get to .06MA at which point the fizzle detector took them out. 3) At 0.6MA a CLEARIN of -.03 gives a kappa of about 1.6 and a CLEARIN of -.05 gives a kappa of about 1.42. 4) The RXL P gain was not turning on until later in the shot. By turning this gain on at 0.1sec the plasma stayed off the inner nose. 5) Using ZXU=+.025 and ZXL=-.02 gave acceptable equilibria for these limiter discharges. 6) The crossover of the OH1 supply causes these plasmas to go SN or DN very briefly. Most of the time these quick excursions lead to small molybdenum injections. 7) Density feedback works with two caveats. The offset coming in on the wire changes from shot to shot and the system is not quite linear. This leads to the observation that feedback thinks everything is fine while the density is drooping and the target point changes from shot to shot. Engineering today: Reliable day today for the power systems. Chopper troubles on shot 1, but they were remedied and away we went. There was a cooling problem that delayed the beginning of the run. Over-cooling of the upper TF arms caused the inner cylinder to get very cold and time was given to the HEAT system to catch up to the excess cooling. CAMAC problems also delayed the run twice. For some reason MAX (SCSI highway) froze and hung the INIT cycle and inadvertant call to the program 'CYCLE' caused a non-STORE condition. Scorecard: 25 shots = 24 plasmas + 1 p.s. test Shot summary for Run 941201 Reload of 941130033 Changes to shot 941130033: ZCUR=0; CLEARIN=-.03; NL_07=7.5e19; IP=-600000 for the shot duration Shot change result ____ _____ ______ 1 plasma - disrupts at .28 chopper problems 2 EFC TMX test shot it chopped 3 no changes plasma - 0.64MA limited - DN - kappa=1.6 4 CLEARIN=-.05; ZXL=-.02 @ .4sec + plasma = 0.64MA limited - right gap ~ .01 5 RCUR=0.64; drop PG3 @ .2s; plasma - 0.64MA nel_04=9e19 and flat limited - right gap=.03 6 RXU=-.005; lower PG3 @ .35 and plasma - 0.64MA much lower after 0.5; make PG3 .02 wide nel_04=8e19 -> 7.2e19 7 turn on P gain for RXL @ .1 plasma - 0.64MA nel_04=8.9e19 and flat limited - no kiss of inner nose 8 RCUR=.645 across segments plasma - .64MA P gain on RXU steps up to 3 nel_04=7.5e19 and flat 9 notch D gain on RCUR at segment switch plasma - .64MA lower P gain on RCUR at segment switch nel_04=7.8->7.5e19 outer gap > .01 during switch 10 drawn ZXU=.025 plasma - .64 MA nel_04=8.2->7.2e19 shark fin 11 lower PG3 early; leave P gain on plasma - .64MA through rampdown for density feedback nel_04=8.0->7.5e19 widen notch in RCUR D gain to .02se shark fin 12 draw the density waveform down sooner plasma - .64 MA nel_04=7.8->7.6e19 big shark fin 13 slow down ZXU change during rampdown plasma - .64MA nel_04=8.2e19 and flat 14 RCUR=.615 @ 1.4sec plasma - .64MA nel_04=8.6->8.4e19 still a fin 15 slow down current rampdown rate plasma - .64MA step down P gain in ZXU and RXU (was 0) nel_04=8.5e19 and flat disrupts later and at .15MA 16 slow down current rampdown rate more plasma - .64 MA nel_04=7.5->7.2e19 disruption later and at .08MA upper x-point stays away 17 permissive to PCX plasma - .64MA nel_04=7.2->6.7e19 18 CLEARIN=-.06 late in rampdown plasma - .64 MA slow Ip rampdown rate until 1.35 then nel_04=7.3->6.8e19 0 at 1.45 19 raise NL_07 gain to 9. plasma - .64MA move Ip rampdown break point to 1.325 nel_04=7.8->7.5e19 20 Ip rampdown back to shot 018 plasma - .64MA nel_04=7.6->7.4e19 21 no changes plasma - .64MA nel_04=7.4->7.0e19 22 move Ip rampdown break point to 1.4 plasma - .64MA nel_04=7.8->7.7e19 23 move Ip rampdown break point to 1.35 plasma - .64MA nel_04=8.6->8.0e19 24 no changes plasma - .64MA nel_04=8.0->7.3e19 25 no changes plasma

Session Leader Comments
Dec 1 1994 08:53:55:440AM		Amanda Hubbard	The plan for this run is to produce stable, reproducible discharges which can be used for diagnostic alignment and checkout purposes. The primary purpose is vertical alignment of the ECE beam (MP040). The discharges will also be used for cross-checking HIREX channels (MP048), and possibly for checking out the NPA and scanning probe. Other diagnosticians are encouraged to use the run for similar purposes; the operators will be receptive as long as they don't involve major perturbations to the plasma. The target discharge is a 'plain vanilla', limited, vertically centered plasma with Ip = 600 kA and moderate density (7.5 e 19) and elongation (1.4). Should this prove difficult to achieve with the new controllers, the target will be modified accordingly. SL A. Hubbard PO J. Goetz
Dec 1 1994 11:16:01:870AM	941201006	Amanda Hubbard	This shot was essentially what is called for - steady density 8 e 19 from 600 ms to 1 s. Making some supposedly very small tweaks for next shot to avoid 'kissing the nose', and reduce early ne overshoot.
Dec 1 1994 11:45:57:540AM	941201007	Amanda Hubbard	This shot is declared to be the first in the ECE alignment scan. Density is steady at the feedback value. There are small shot-to-shot variations (~ 10 19 m-2) due to an offset in the TCI. Not much we can do about this. John may still make a few tweaks in the upper x-point to keep down the moly injections. This should hopefully not affect the main plasma. For next shot ECE beam will be moved down by 6 cm. (9.0939 V)
Dec 1 1994 11:47:41:550AM	941201007	Amanda Hubbard	Good shot. 7.5 e 19 m-3.

Physics Operator Comments
Dec 1 1994 08:30:56:950AM		John Goetz	Mini-proposal #040 - ECE alignment Run a set of stable, reproducible discharges to be used for ECE alignment. Various other diagnostics will piggyback for check-out purposes. These plasmas will have: Ip=0.6; Bt=5.3; nel_04=7.5e19; z0=0; R0=.66; limited Start from Shot 941130033 This shot had acceptable parameters at 0.3sec. Try and keep the equilibrium for the rest of the shot. Changes: ZCUR=0.; CLEARIN=-.03; NL_07=7.5e19; IP=-600000 Hybrid coldstart - all matrices respond
Dec 1 1994 09:58:16:040AM	941201001	John Goetz	Shot 941201001: Plasma - disrupts at 0.28sec Plenty of lovely oscillations in all directions Chopper malfunction For 002: Fix chopper and test chopper
Dec 1 1994 09:58:56:450AM	941201002	John Goetz	Shot 941201002: EFC-TMX only it chopped For 003: no changes
Dec 1 1994 10:17:14:290AM	941201003	John Goetz	Shot 941201003: Plasma - 0.64 MA - disrupts @ 1.32 sec density a little high early limited - double null - kappa=1.6 For 004: CLEARIN=-.05 for all time ZXL=-.02 from 0.4sec on
Dec 1 1994 10:35:26:730AM	941201004	John Goetz	Shot 941201004: Plasma - 0.64 MA - disrupts @ 1.32 sec density still a little high early limited - kappa=1.4 - only grazes the inner nose for a tick For 005: RCUR=0.64 drop PG3 @ 0.2sec hybrid enable B_SIDE_LOWER
Dec 1 1994 10:56:33:230AM	941201005	John Goetz	Shot 941201005: Plasma - 0.64 MA nel_04 = 9e19 and flat limited - kappa=1.4 - outer gap=.03 For 006: RXU = -.005 (to straighten up plasma) drop PG3 @ 0.2sec and dramatically lower after 0.5 make PG1 .02 sec wide (more argon Igor)
Dec 1 1994 11:14:59:890AM	941201006	John Goetz	Shot 941201006: Plasma - 0.64 MA nel_04 = 8e19 -> 7.2e19 limited - kappa=1.4 - outer gap=.03 two moly injections For 007: RXL gain turned on @ .1sec (try to keep it off the inner nose early) drop PG3 @ 0.2sec
Dec 1 1994 11:35:20:940AM	941201007	John Goetz	Shot 941201007: Plasma - 0.64 MA nel_04 = 8.9e19 and flat (offset from TCI has changed) limited - kappa=1.4 - outer gap=.03 two moly injections (possible upper x-point formation) For 008: RXU P gain steps up to 3. RCUR =.645 across segments
Dec 1 1994 11:57:29:960AM	941201008	John Goetz	Shot 941201008: Plasma - 0.64 MA nel_04 = 7.8e19 and flat limited - kappa=1.4 - outer gap=.03 no moly injections but still a little upper x-point formation For 009: notch D gain in RCUR at segment switch lower P gain in RCUR at segment switch ( try to remove thrash )
Dec 1 1994 12:13:42:850PM	941201009	John Goetz	Shot 941201009: Plasma - 0.64 MA nel_04 = 7.9e19 -> 7.5e19 limited - kappa=1.4 - outer gap=.03 no overshoot on the RCUR during segment switch - outer gap remains > .01 For 010: drawn ZXU=.025 (try and keep upper x-point away)
Dec 1 1994 12:27:07:560PM	941201010	John Goetz	Shot 941201010: Plasma - 0.64 MA nel_04 = 8.2e19 -> 7.2e19 limited - kappa=1.4 - outer gap=.03 shark fin For 011: widen notch in RCUR D gain to .02 sec lower PG3 early extend P gain for density feedback through rampdown
Dec 1 1994 12:49:28:870PM	941201011	John Goetz	Shot 941201011: Plasma - 0.64 MA nel_04 = 8.0e19 -> 7.5e19 limited - kappa=1.4 - outer gap=.03 still a shark fin For 012: draw the density waveform down earlier
Dec 1 1994 01:03:00:240PM	941201012	John Goetz	Shot 941201012: Plasma - 0.64 MA nel_04 = 7.8e19 -> 7.6e19 limited - kappa=1.4 - outer gap=.03 still a shark fin For 013: ZXU change in ramp-down less severe
Dec 1 1994 01:15:20:560PM	941201013	John Goetz	Shot 941201013: Plasma - 0.64 MA nel_04 = 8.2e19 and flat (TCI offset changed) limited - kappa=1.4 - outer gap=.03 still a shark fin - still an upper x-point at 1.05sec For 014: RCUR = 0.615 @ 1.4s
Dec 1 1994 01:33:14:040PM	941201014	John Goetz	Shot 941201014: Plasma - 0.64 MA nel_04 =8.6->8.4e19 (TCI offset changed) limited - kappa=1.4 - outer gap=.03 still a shark fin For 015: slow down current ramp down rate step down P gain in ZXU and RXU at 1.0sec (was going to 0.)
Dec 1 1994 01:57:23:820PM	941201015	John Goetz	Shot 941201015: Plasma - 0.64 MA nel_04 =8.5e19 and flat (TCI offset changed) limited - kappa=1.4 - outer gap=.03 disrupts later - at a current of 150kA For 016: slow down current ramp down rate some more
Dec 1 1994 02:08:39:700PM	941201016	John Goetz	Shot 941201016: Plasma - 0.64 MA nel_04 = 7.5->7.2e19 limited - kappa=1.4 - outer gap=.03 disrupts later - at a current of 80kA (1.46sec) For 017: permissive to PCX
Dec 1 1994 02:21:48:870PM	941201017	John Goetz	Shot 941201017: Plasma - 0.64 MA nel_04 = 7.2->6.7e19 limited - kappa=1.4 - outer gap=.03 For 018: CLEARIN=-.006 late in rampdown slow Ip rampdown rate until 1.35 then bring to 0. by 1.45sec
Dec 1 1994 02:35:50:990PM	941201018	John Goetz	Shot 941201018: Plasma - 0.64 MA nel_04 = 7.3->6.8e19 limited - kappa=1.4 - outer gap=.03 Ip rampdown o.k. - disrupts at 1.49sec (.06MA) For 019: raise NL_07 gain to 9. move Ip rampdown break point to 1.325
Dec 1 1994 02:50:39:880PM	941201019	John Goetz	Shot 941201019: Plasma - 0.64 MA nel_04 = 7.8->7.5e19 limited - kappa=1.4 - outer gap=.03 Ip rampdown o.k. - disrupts at 1.41sec (.07MA) For 020: move Ip rampdown break point to 1.35
Dec 1 1994 03:48:06:800PM	941201020	John Goetz	Shot 941201020: Plasma - 0.64 MA nel_04 = 7.6->7.4e19 limited - kappa=1.4 - outer gap=.03 For 021: no changes
Dec 1 1994 03:59:00:750PM	941201021	John Goetz	Shot 941201021: Plasma - 0.64 MA nel_04 = 7.4->7.0e19 limited - kappa=1.4 - outer gap=.03 For 022: change Ip rampdown break point to 1.4sec
Dec 1 1994 04:24:20:350PM	941201022	John Goetz	Shot 941201022: Plasma - 0.64 MA nel_04 = 7.9->7.8e19 limited - kappa=1.4 - outer gap=.03 For 023: change Ip rampdown break point to 1.35sec
Dec 1 1994 04:42:01:900PM	941201023	John Goetz	Shot 941201023: Plasma - 0.64 MA nel_04 = 8.6->8.0e19 limited - kappa=1.4 - outer gap=.03 For 024: no changes
Dec 1 1994 04:57:24:530PM	941201024	John Goetz	Shot 941201024: Plasma - 0.64 MA nel_04 = 8.0->7.3e19 limited - kappa=1.4 - outer gap=.03 For 025: no changes
Dec 1 1994 05:12:56:980PM	941201025	John Goetz	Shot 941201025: Plasma - 0.64 MA nel_04 = 8.4->8.1e19 limited - kappa=1.4 - outer gap=.03

Engineering Operator Comments
Shot	Time	Type	Status	Comment
1	08:56:02:950AM	Plasma	Bad	chopper did not chop
2	09:51:27:620AM	Test	Ok	chopper test
3	09:59:55:010AM	Plasma	Ok	no faults
4	10:17:49:850AM	Plasma	Ok	no faults
5	10:35:54:420AM	Plasma	Ok	no faults
6	10:56:52:440AM	Plasma	Ok	no faults
7	11:16:07:340AM	Plasma	Ok	no faults
8	11:36:01:020AM	Plasma	Ok	no faults
9	11:54:18:120AM	Plasma	Ok	no faults
10	12:13:32:110PM	Plasma	Ok	no faults
11	12:27:02:080PM	Plasma	Ok	no faults
12	12:42:25:100PM	Plasma	Ok	no faults
13	01:04:20:040PM	Plasma	Ok	No Faults.
14	01:19:43:220PM	Plasma	Ok	No faults.
15	01:39:13:380PM	Plasma	Ok	No Faults.
16	01:53:44:770PM	Plasma	Ok	No faults,
17	02:08:08:240PM	Plasma	Ok	No faults.
18	02:22:34:850PM	Plasma	Ok	No faults.
19	02:38:54:480PM	Plasma	Ok	No Faults.
20	03:34:31:720PM	Plasma	Ok	No faults
21	03:50:08:430PM	Plasma	Ok	No faults
22	04:03:35:220PM	Plasma	Ok	Nofaults
23	04:31:08:960PM	Plasma	Ok	No Faults.
24	04:43:28:610PM	Plasma	Ok	No Faults.
25	04:58:26:180PM	Plasma	Bad