| Miniproposals | ||||||||||
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| Operators | |
| Session leader(s): | Chuck Kessel |
| Physics operator(s): | Ian Hutchinson |
| Engineering operator(s): | Andy Pfeiffer,Bill Parkin,Bill Byford |
| Engineering Operator Run Comment |
| MP576 SL Chuck Kessel PO Ian Hutchinson |
| Session Leader Plans |
| Entered: Sep 2 2009 07:46:48:323PM |
| Author: Chuck Kessel |
| Goal: establish improved startup for ITER-like discharges by developing reliable diverting time and making the diverting time as early as possible.
Recover discharge 1080221010 with AT startup programming, remove LH and ICRF heating. In corporate shaping improvements (target kappa = 1.8, before or at end of ramp) established with AT rampup in 1090710 run day. (5 shots) 1) establish fastest rampup possible with power supplies (targeting 1.35 MA in 500-700 ms (5 shots) 2) begin to push divert time to earlier times a. with earlier crowbar if possible (5 shots) b. modification of PF coil pre-program to pull X-point into VV sooner (EF1L and/or EF2L) (10 shots) 3) introduce 1-2 MW ICRF power at or about the divert time and confirm the established scenario is preserved (3 shots) |
| Physics Operators Plans |
| Entered: Sep 2 2009 05:16:49:643PM |
| Author: Ian Hutchinson |
| MP576
This run is primarily for developing controlled ramp-ups with early diversion. That means early crowbar. The shots from this campaign most suitable for the segment 1 are from the low-field startup that was developed also with early crowbar. We will therefore start from 1090710015, but adjust EF1 and EF4 for the field. Engineering setup should be as for 1090710015. The measured values for this shot are: TF current -87443 EF1L -5994 EF4 -1310 Compared with a startup from 2 Sep: TF -151000 EF1L -5840 EF4 -1273. Thus the deltas to be applied to 1090710015 for 150000A TF are nominally. EF1 +154A EF4 +37A. These will be applied symmetrically. More generally dEF1/dTF = 2.46 A/kA dEF4/dTF = 0.59 A/kA. For general field changes. Then we will adjust the preprogramming and currents and positions to get even earlier diversion with a current ramp rate consistent with the controlled ITER like startup required. |
| Session Leader Summaries |
| Entered: Sep 3 2009 06:15:24:260PM |
| Author: Chuck Kessel |
| MP576 Improvement of ITER-Like Startup
003 produced good smooth ramp to 1.3 MA, with a very early left gap > 0, while divert is > 120 ms, but based on non-ITER shot (JFT-2M?) 005 Ip ramp then disrupt, divert time similar to AT scenarios at about 170-180 ms, kappa is high early 006 Ip to 1.2 MA by 700 ms, divert at 200 ms, return to more typical plasma programming, improving density, disrupt at 770 ms 007 reduce Ip to 1.0 MA by 500 ms to get discharge setup, produced full discharge thru rampdown, very good Ip(t), divert at 200 ms, kappa up to 1.65 008 like 007 but make shape closer to ITER specs, higher kappa to 1.7, upper triangularity higher, divert time at 200 ms, disrupt at 1.42 s 010 full discharge thru rampdown, divert time at 160 ms, H-mode at end of flattop 011 good reproduction of 010, full discharge thru rampdown 012 go to 1.2 MA at 700 ms, full discharge thru rampdown, positioning x-pt in vessel early at 100 ms, though plasma not connecting until 120-160 ms. lots of H-modes in flattop, li drops with H-modes, smooth kappa rise in ramp 013 1.2 MA by 700 ms, very early divert at 100 ms, short kiss of inner wall at 150 ms, li little lower in this early phase, H-modes in flattop with disrupt at beginning of rampdown 015 1.2 MA at 670 ms, otherwise similar to 013 017 raise Ip to 1.3 MA, good rampup, divert at 100 ms, plasma is vertically waffling after this and then lock to lower x-pt at 140 ms, disrupt after 900 ms 018 similar to 017, ran out to 1.5 s, beginning of rampdown 022 Ip to 1.3 MA at 670 ms, similar divert timing to 018, disrupt at 1.05 s 024, 025 Ip to 1.3 MA at 670 ms, pushing early divert at 100 ms with larger bore plasmas very early, helping somewhat with bouncing, disrupts in early rampdown, H-modes in end of flattop extending into rampdown 027, 028 MUCH better early time plasma shape leading to diverted plasma with larger bore, divert time 120-140 ms, 028 full discharge thru rampdown 029 1.3 MA at 670 ms, ICRF 1 MW on at 200 ms, divert 100-120 ms, good plasma shapes early, disrupt after 1.2 s 030 same as 029, ICRF 1 MW (actually 1.2 MW) at 150 ms, making Te higher as it should 033 Ip 1.3 MA at 670 ms, ICRF 1 MW on at 150 ms, looks like H-mode start there from density rise, magnetics getting messed up, but divert time appears to be 80-100 ms, disrupt at 1.35 s Overall, VERY productive day. Early diverting was obtained for ITER-like discharges going up to 1.3 MA, with divert time ranging from 80-120 ms, even better than standard AT scenarios. This startup will be incorporated into AT scenarios. Tremendous effort by Hutchinson to work on this early phase and on Ip rampup. Smooth Ip rampup to 1.3 MA with crowbars at 40 ms. ICRF injected early just after divert time, discharge scenario was preserved, with last discharge showing early H-mode onset at 150-200 ms. Ohmic H-modes were obtained in the flattop, will some spilling into the rampdown. We had a lot of "things" entering the plasma and causing very high radiated power with disruption, the cause is not clear. Thanks to Wolfe for plasma control twiddles and disruption investigations. |
| Physics Operator Summaries |
| Entered: Sep 3 2009 05:26:30:990PM |
| Author: Ian Hutchinson |
| Controlled early diversion current ramps were obtained as per the MP576.
The difficulty with this configuration and objective is that the segment switch is at a time (.08s) in the middle of where the action is. So really you need both segments adjusted to get what you want. There is a significant effect at segment switch from the rcur offset change from 1000 (or on early shots 2000) to zero. Moreover the plasma is not fully under feedback by the times we care about, so there is a good deal of voltage preprogramming to undertake. The run went tolerably well from the viewpoint of the discharge development. Diversions at 0.1s and earlier were obtained, and controlled. We were able to get to 1.3MA (q=3.1) by .65s and could probably get there earlier with more development time. Indeed, we even used ICRF in the startup as per the MP and got hot plasmas. OH1 crossovers were noticable but probably not dominant. It appeared that locked modes were occuring at the elevated current. We doubled the A-Coil current and they went away. Ohmic H-modes were easily obtained at >1MA. They made rampdowns more difficult. Elongations ~1.75 were routinely obtained during flat top. Numerous magnetics errors were reported, some of which were clearly serious for control. Some log entries by Wolfe describe shots to be wary of. This may mean that with working magnetics one gets different results from reloading shots from this day! Numerous disruptions were obtained, these were caused mostly by injections and some by control problems. Future development of this scenario will require starting from both segment 1 and segment 2 of shots 32 or 33, and then drawing changes. I recommend against trying to patch segment 2s from other run days on to this seg 1. Scorecard ---------
Shot,Duration(s),Ipmax(MA),Result Shot,Duration(s),Ipmax,Result
| 01 0.103 0.395 Plasma | 02 0.129 0.484 Plasma |
| 03 0.710 1.297 Plasma | 04 0.000 0.028 Fizzle |
| 05 0.704 1.199 Plasma | 06 0.769 1.293 Plasma |
| 07 1.998 1.000 Plasma | 08 1.447 1.004 Plasma |
| 09 0.249 0.046 Fizzle | 10 1.983 1.000 Plasma |
| 11 1.974 1.000 Plasma | 12 1.974 1.200 Plasma |
| 13 1.515 1.199 Plasma | 14 0.277 0.053 Fizzle |
| 15 1.959 1.191 Plasma | 16 0.286 0.433 Plasma |
| 17 0.934 1.354 Plasma | 18 1.502 1.291 Plasma |
| 19 0.279 0.284 Plasma | 20 0.000 0.002 Dud |
| 21 0.455 0.987 Plasma | 22 1.066 1.363 Plasma |
| 23 0.238 0.045 Dud | 24 1.635 1.290 Plasma |
| 25 1.630 1.290 Plasma | 26 0.261 0.057 Fizzle |
| 27 1.533 1.292 Plasma | 28 1.982 1.289 Plasma |
| 29 1.184 1.302 Plasma | 30 1.099 1.302 Plasma |
| 31 0.250 0.046 Fizzle | 32 0.744 1.394 Plasma |
| 33 1.373 1.299 Plasma
Date 1090903: 33 shots. 26 plasmas. 5 fizzles. 2 duds. 0 System Error.
(Plasma = Ip gt 60.0 kA Dud = H_alpha lt 0.40 V)
Total plasma duration: 32.24 s (exceeding -39 kA)
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| Session Leader Comments | |||
| Sep 3 2009 09:49:11:363AM | 1090903003 | Chuck Kessel | WOW
Ip ramp good kappa is low, so q95 too low divert time very early, about 70 ms, then bounces at 400 ms HOwEVER, there is mixing of discharge programming from various places that needs to be sorted out |
| Sep 3 2009 11:15:30:927AM | 1090903007 | Chuck Kessel | full diacharge thru rampdown
Ip to 1 MA, avoid disruptions rampup Ip(t) is very good, progressively decreasing dIp/dt AT divert clearly getting established, trying to avoid the bounce later |
| Sep 3 2009 11:24:13:430AM | 1090903008 | Chuck Kessel | Ip = 1 MA
higher triangularity stayed in L-mode, li got high in flattop disruption at 1.45 s |
| Sep 3 2009 11:55:50:270AM | 1090903010 | Chuck Kessel | Ip = 1 MA
full discharge left gap > 0 at 150 ms, divert time appears the same kappa up to 1.7, targeting 1.8 H-mode in end of flattop triangularity not as high as last year, but may be OK |
| Sep 3 2009 11:59:28:163AM | 1090903011 | Chuck Kessel | good reproduction of 010
smoother outer gap |
| Sep 3 2009 12:09:42:760PM | 1090903012 | Chuck Kessel | Ip = 1.2 MA, full discharge,
left gap > 0 and divert about 180-200 ms smoother kappa ramp to 1.7 H-modes in flattop, good for lower li as we raise Ip |
| Sep 3 2009 12:26:30:063PM | 1090903013 | Chuck Kessel | Ip = 1.2 MA, disrupt at start of rampdown
left gap > 0 and divert about 100 ms, super! it bounces off inboard at 150 ms H-modes in flattop L-mode at beginning of rampdown, kappa = 1.7, li higher |
| Sep 3 2009 01:03:48:000PM | 1090903015 | Chuck Kessel | Ip = 1.2 MA
full discharge very early divert at 100 ms again, some bouncing competition between plasma growth to full bore and attaching to x-pt 2 H-modes in flattop |
| Sep 3 2009 01:53:00:503PM | 1090903018 | Chuck Kessel | Ip = 1.3 MA at 670 ms, Ip ramp nice
disrupt at rampdown vertical instability? other stuff too |
| Physics Operator Comments | |||
| Sep 3 2009 08:59:10:047AM | Ian Hutchinson | Many physop adjustments carefully documented were lost when firefox crashed.
Broadly I started from 1090710015 and changed a load of things. | |
| Sep 3 2009 09:24:00:040AM | 1090903001 | Ian Hutchinson | Disrupts at .1 sec because of loss of zcur control, starting about .08s.
Back off clearin demand at .1s. No that's not the reason. The reason is that the zcur controller on chopper did not turn on till 0.09s. 10ms after the seg switch. Fix chopper controller. Clearin to -.01s. Adjust gain switches on fast zcur to accommodate early seg switch. |
| Sep 3 2009 09:34:44:500AM | 1090903002 | Ian Hutchinson | Disrupts at 0.12s. Loss of z-control.
EFC floors at .1s and stays that way till the disruption. Slow zcur controller derivative and proportional are wrong before .1s. Set them to the same as afterwards. Set clearin to -.015 at .1s |
| Sep 3 2009 09:55:05:897AM | 1090903003 | Ian Hutchinson | Plasma. Disrupts at 0.7sec at 1.3MA.
Rcur gain programming is incorrect in segment 2. Its proportional gain is zero prior to 0.9s. Set to 6. All of this is irrelevant. Somehow segment 2 is incorrect and a strange mixture of yesterdays seg 2 and what I want. Stop this. Load seg 2 from 1090710015. Adjust Ip Set fast zcur controller to 0s. Load. Set TF in seg 2 to seg 1 values. Load. |
| Sep 3 2009 10:05:43:777AM | 1090903004 | Ian Hutchinson | Fizzle.
Gas puff to 20ms from 25ms. |
| Sep 3 2009 10:32:04:740AM | 1090903005 | Ian Hutchinson | Disrupts at 0.7s.Apparent vertical instability. Locked mode perhaps at .65s.
Lower clearin to .01 from .012. Ramp density to .7e20 |
| Sep 3 2009 10:50:03:900AM | 1090903006 | Ian Hutchinson | Plasma disrupts at .76s.This disruption not caused by zcur control loss.
Strange apparent instability on gas puff. F13 was in error. Clearin ramp start earlier in seg 2. Limit Ip to 1MA till we figure out the other problems. Zap F13. Add derivative gain of 3 to nl04. |
| Sep 3 2009 11:05:25:753AM | 1090903007 | Ian Hutchinson | Plasma to rampdown.
RXU and ZXU changed to give more ITER-like shape. zcur ramps to 0. Ramp clearin faster. Load |
| Sep 3 2009 11:20:49:193AM | 1090903008 | Ian Hutchinson | Disrupts at 1.45s.VDE.
Fix TF rampdown Fix nl04 Start Ip ramp at 1.4s Lower clearin to .008 at 1s. EF1V to -50V at .1s. Load. |
| Sep 3 2009 11:32:41:607AM | 1090903009 | Ian Hutchinson | Fizzle. |
| Sep 3 2009 11:48:12:847AM | 1090903010 | Ian Hutchinson | Plasma to rampdown.
VEF1 to 50V at .08s from 100V. Clearin to +0,01 at .075s. |
| Sep 3 2009 11:56:29:100AM | 1090903011 | Ian Hutchinson | Plasma to rampdown.
Ip flattop to 1.2MA VEF1 to 0V at .08s. zxl proportional to 4 at .1s (from 2.5) nl04 to .8e20 at 1s. |
| Sep 3 2009 12:17:58:107PM | 1090903012 | Ian Hutchinson | Plasma to rampdown.
Get rid of the ICEF1 proportional point at about .05s. Not helpful. Ip to 1MA at 0.46s. |
| Sep 3 2009 12:28:26:737PM | 1090903013 | Ian Hutchinson | Plasma disrupts at 1.5s.
Add clearin point at +.015 at .1s Lower clearin 1mm to .007 after 1.s |
| Sep 3 2009 12:45:11:570PM | 1090903014 | Ian Hutchinson | Fizzle.
ICEF4 to 2500A from 1000A. This should move EF3 away from saturation. ICEF4 to -1310 from -1300A in startup. Ip programming earlier 1.2MA at .65s nl04 to .9e20 in flat top. VEF1 to zero at about .06s. |
| Sep 3 2009 12:57:32:123PM | 1090903015 | Ian Hutchinson | Plasma to rampdown. Some early zcur issues.
EV1V to -10V at .05s. |
| Sep 3 2009 01:13:54:190PM | 1090903016 | Ian Hutchinson | Early disruption because of vertical loss of control.
Set Ip to 1.3MA. at 0.65s. 1MA at .42s. Move the .1s clearin point back to .01. Adjust zcur programming to go down slower. Lower slow zcur proportional to 1. |
| Sep 3 2009 01:25:57:963PM | 1090903017 | Ian Hutchinson | Plasma 1.3MA. Disrupts at .93s. Locked mode at .86s.
Increase EF3lower coeff of b21proj from -1.20880e-08 to -2.40e-08. Should give more A-coil current. Slow zcur proportional to .8 from 1 in early seg 1. |
| Sep 3 2009 01:39:56:373PM | 1090903018 | Ian Hutchinson | Disrupts at 1.5s. Locked mode seems gone.
raise nl04 to 1e20 Install extra fast zcur gain points at .06s in seg 2 with higher D and P, though still not all the way up to the full level used for the main shot. |
| Sep 3 2009 01:57:59:210PM | 1090903019 | Ian Hutchinson | Disrupts at .08s. Something bad happens at .04s. Not my fault I think.
Make clearin gain 5 at seg switch and only up to 10 later. Try to avoid the big OH2 thrash. |
| Sep 3 2009 01:58:26:723PM | 1090903020 | Ian Hutchinson | Got 2ms granularity error. This is a no power shot. |
| Sep 3 2009 02:23:30:470PM | 1090903021 | Ian Hutchinson | Disrupts at .44 owing to big injection at .433s
Rcur to .65 from .64 at .04s Tweak clearin gain. Tweak zxl early. |
| Sep 3 2009 02:36:26:510PM | 1090903022 | Ian Hutchinson | Disrupts at 1.06s.
Make OH2V 0 not 10 at .07s. |
| Sep 3 2009 02:55:45:307PM | 1090903022 | Ian Hutchinson | Shot 23. No EF3 or plasma.
Increase seg 1 rcur gain at .05s. Rcur to .658 at .05s. Small clearin tweak. |
| Sep 3 2009 03:06:30:437PM | 1090903024 | Ian Hutchinson | Disrupts at 1.63s.
Clearin to .012 at .1s Rcur to .66 at .05s. |
| Sep 3 2009 03:19:10:630PM | 1090903025 | Ian Hutchinson | Disrupts at 1.617.
Rcur to .663 at .05s. Clearin to .013 Start Ip rampdown at 1.4s. |
| Sep 3 2009 03:36:04:150PM | 1090903026 | Ian Hutchinson | Fizzle.
OH2Vs to +30V from -10V at .05s. Rcur offset to 1000 from 2000. |
| Sep 3 2009 03:47:00:110PM | 1090903027 | Ian Hutchinson | Disrupts at 1MA, slightly earlier. Might be z-control problem.
Tweaks at the rampdown. Clearin up 1mm round .1s |
| Sep 3 2009 04:00:33:300PM | 1090903028 | Ian Hutchinson | Plasma to rampdown.
EF1V to -50 from -10V at .05s. Clearin to .014 at .1s |
| Sep 3 2009 04:14:37:853PM | 1090903029 | Ian Hutchinson | Disrupts at 1.16s.Looks like an injection.
Clearin to .014 at .09s. EF1Vs to -80V at .05s. Rcur to .662 at .08s. |
| Sep 3 2009 04:26:37:263PM | 1090903030 | Ian Hutchinson | Disrupts at 1.1s.
Raise fill puff to 27ms. EF1V to -100 at .05-.1s clearin to .015 at .09s. Rcur to .667 at .05s. |
| Sep 3 2009 04:39:41:347PM | 1090903031 | Ian Hutchinson | Fizzle.
Fill puff to 24ms. ZXL gain to 5 from 4 at .1s |
| Sep 3 2009 04:53:28:273PM | 1090903032 | Ian Hutchinson | Disrupts at .73s.
Move out rxl at .4s to zero try to prevent slot divertor effect. EF1Vs to -50V in seg 2 early. |
| Sep 3 2009 05:26:08:350PM | 1090903033 | Ian Hutchinson | Disrupts at 1.35s.
Magnetics errors on this shot. |
| Engineering Operator Comments | ||||
| Shot | Time | Type | Status | Comment |
| 1 | 09:02:13:940AM | Plasma | Ok | |
| 2 | 09:22:10:180AM | Plasma | Ok | |
| 3 | 09:35:03:140AM | Plasma | Ok | |
| 4 | 09:55:09:130AM | Plasma | Ok | |
| 5 | 10:15:12:700AM | Plasma | Ok | |
| 6 | 10:29:43:957AM | Plasma | Ok | |
| 7 | 10:48:33:997AM | Plasma | Ok | |
| 8 | 11:03:27:847AM | Plasma | Ok | |
| 9 | 11:17:44:240AM | Plasma | Ok | |
| 10 | 11:30:50:650AM | Plasma | Ok | |
| 11 | 11:44:10:237AM | Plasma | Ok | |
| 12 | 11:57:30:693AM | Plasma | Ok | |
| 13 | 12:13:27:823PM | Plasma | Ok | |
| 14 | 12:27:11:300PM | Plasma | Ok | |
| 15 | 12:43:12:930PM | Plasma | Ok | |
| 16 | 12:57:01:170PM | Plasma | Ok | |
| 17 | 01:09:58:910PM | Plasma | Ok | |
| 18 | 01:23:20:197PM | Plasma | Ok | |
| 19 | 01:39:58:357PM | Plasma | Ok | |
| 20 | 01:52:46:753PM | Plasma | Bad | No power shot |
| 21 | 02:06:20:010PM | Plasma | Ok | |
| 22 | 02:20:07:000PM | Plasma | Ok | |
| 23 | 02:33:57:997PM | Plasma | Bad | EF 3 fault in check |
| 24 | 02:51:31:180PM | Plasma | Ok | |
| 25 | 03:06:05:157PM | Plasma | Ok | |
| 26 | 03:19:05:333PM | Plasma | Ok | |
| 27 | 03:31:55:197PM | Plasma | Ok | |
| 28 | 03:45:06:950PM | Plasma | Ok | |
| 29 | 03:58:25:330PM | Plasma | Ok | |
| 30 | 04:11:19:993PM | Plasma | Ok | |
| 31 | 04:24:26:623PM | Plasma | Ok | |
| 32 | 04:37:28:033PM | Plasma | Ok | |
| 33 | 04:51:24:210PM | Plasma | Ok | |
| System Availability | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
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