| Miniproposals | ||||||||||
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| Operators | |
| Session leader(s): | Robert Granetz |
| Physics operator(s): | Steve Wolfe |
| Engineering operator(s): | Bill Cochran |
| Engineering Operator Run Comment |
| MP 371: 2MA Operation at 8T/Granetz/Irby/Wolfe/Cochran/Byford/Parkin |
| Session Leader Plans |
| Physics Operators Plans |
| Session Leader Summaries |
| Entered: Jul 7 2004 03:49:04:227PM |
| Author: Robert Granetz |
| Run summary for run 1040405 (Monday): MP 371 -- 2 MA operation at 8 T Session leader: R. Granetz/J. Irby Physics operator: S. Wolfe Summary: Not much progress made today either. We had a full-length shot at 1.2 MA and 8 T, but all attempts at 1.4 MA disrupted, most likely due to radiation from molybdenum and/or moly injections. We also lost a lot of time dealing with breaker/crowbar problems. The RF worked well, with 4.5 MW of power, but we didn't get a chance to test whether it was responsible for the large amounts of moly. ------------------------------------------------------------------------------- Run Plan: Start the physics run with a repeat of 1040331001 (1.05 MA, 5.5 T, Prf=4 MW) to confirm that TF instrumentation is all working. When ready, load shot 1040331006 (1.05 MA, 8.0 T) from last week. (Set PLC TF limit at 235 kA and TF start at t=-1.5 s). Raise Ip in 0.2 MA increments, while also raising the A-coil current and the PLC OH/EF limits appropriately. (Session leaders will specify the desired A-coil current for each shot.) We want RF heating in order to help with OH flux budget, but if it introduces lots of impurities, we may want to rethink this. Monitor: (1) locked mode diagnostics (2) halo currents and Ih*Bt product on disruptions (3) TF, OH, and EF instrumentation If locked modes appear, we have the option of raising the plasma density, in addition to the A-coil current, depending on how successful the RF is at heating the plasma. If it is feasible to shorten the flattop, we should do it in order to reduce magnet heating and increase the rep rate. ------------------------------------------------------------------------------- Shot 09 -- Plasma. 1 MA, 8 T, full length, Prf=4.0-2.0 MW. First good shot of the miniproposal. Next shot: go to 1.2 MA Shot 10 -- Plasma. Good shot. 1.2 MA, 8 T, full length, Prf= ~3 MW. About 0.5-0.7 keV of heating on the GPC. A-coil current is 1500 A (programmed for 2000 A in PCS). Next shot: go to 1.4 MA; raise A-coil current by 500 A Shot 11 -- Plasma. Disrupted at t=1.11 s. I_halo_L=110 kA, I_halo_U=50 kA. 1.4 MA, 7.9 T. There are a number of moly injections which undoubtedly caused the disruption. (Some can be seen on the video.) No locked mode. Prf=4.5 MW, nice waveform. Next shot: increase inboard gap by 5 mm. Shot 14 -- Plasma. Disrupted at t=1.06 s. I_halo_L=140 kA, I_halo_U=50 kA. 1.4 MA, 7.9 T. Looks the same as shot 11. No locked mode. Prf=4.5 MW. Next shot: try turning off the RF, on the hunch that it might be producing impurity injections. Also raise the density a little. Shot 15 -- Plasma, but disrupted very early. |
| Physics Operator Summaries |
| Entered: Jul 7 2004 04:36:49:770PM |
| Author: Steve Wolfe |
| Physics Operator Summary for Monday 5-APR-2004 MP#371: 2MA operation SL: Granetz/Irby PO: Wolfe EO: Cochran, Byford, Parkin Engineering Setup: ------------------ ECDC overnight on Sunday (D2), stopping 2 hours before the run. Run begins at 09:00 and ends at 17:00. Power systems the same as 1040331001 (1.05 MA, 5.4 T, lower X-point) Power systems may need to be tested after the 13.8 kV power failure. A-coils should be configured as on 1040331001 (+Dtop -Dbot -Jtop +Jbot), 3kA, 600V, enabled. Gas setup: fill B-Top with 6 psi D2 Hybrid enabled (PG4) fill B-side lower with 1 psi Ar Hybrid enabled (PG1) leave B-side upper with 15 psi He3 Hybrid disabled (PG2) fill C-side with 30 psi D2 Hybrid enabled (PG3) Disable NINJA Enable the following gate valves, assuming no vacuum problems: ECE, VUV, DNB Necessary diagnostics: ECE (set for 8 tesla), TCI, halo current diagnostics, TF scanner and OH coax resistance and thermocouple instrumentation, Chromex He monitor ------------------------------------------------------------------------------- RF Setup: All four transmitters in RUN-ON by 08:00, all at 80 MHz ------------------------------------------------------------------------------- Run Plan: 1) Start with a repeat of 1040331001 (1.05 MA, 5.4 T, Prf=4 MW) to confirm that TF instrumentation is all working, and to determine if additional boronization recovery is necessary. 2) When ready, load shot 1040331006 (1.05 MA, 8.0 T). (Set PLC TF limit at 235 kA and TF start at t=-1.5 s). Enable B-side upper for He3 puff; set pg2 pulse to 10msec Confirm/refine 8 Tesla startup 3) Raise Ip in 0.2 MA increments to 2MA, while also raising the A-coil current and the PLC OH/EF limits appropriately. (Session leaders will specify the desired A-coil current for each shot.) We want RF heating in order to help with OH flux budget, but if it introduces lots of impurities, we may want to rethink this. Limited variation of He3 puff to optimize heating may be attempted; we probably do not want to run H-modes unless they are very steady EDA's, so power should be kept below the L-H threshold. Monitor: (1) locked mode diagnostics (2) halo currents and Ih*Bt product on disruptions (3) TF, OH, and EF instrumentation If locked modes appear, we have the option of raising the plasma density, in addition to the A-coil current, depending on how successful the RF is at heating the plasma. If it is feasible to shorten the flattop, we should do it in order to reduce magnet heating and increase the rep rate. Results: ------- No progress toward 2MA was made today. The highest current we got to was 1.45MA, and all of those disrupted with radiation or injection problems. By the end of the day the RF was staying on at the 4.5MW level pretty well, but the Prad was also high and for the last shots we tried turning it off for shot#15. Unfortunately, the gas turned on too hard and it disrupted before the rf would have come on; the last shot was a fizzle, so we did not get a chance to see how an ohmic shot would have done. The run was plagued by power supply (and alternator) problems at the 8T level. Bill found that several devices in cabinet 6 were getting low gate drive, and changed the driver board, but this did not fix all of the problems. We also had (apparently spurious) IOC indications which caused crowbars and breaker trips. On one shot the alternator DC breaker tripped, which eventually led to a crowbar from low line voltage fault. Shots# 7, 9, 10, had tf faults before the end of the plasma. Shots #11 and 14 had disrupions followed by power supply faults; the IOC on shot 14 came after the end of the tf pulse. Mo radiation was high on all RF shots, and may have been high even in the ohmic phase. It is not clear that the boronization is doing any good for Prad. It did seem to have affected the startup however. Shot 4, 1MA at 5.4T, had a long eda at 130kJ with rather poor RF; shot 5, with better but still not constant RF got to 160kJ before the first H->L. We did not get a good fiducial with which to judge the quality of the boronzation, but the Prad foil seemed to be going up to the RF power. We may have a broken tile someplace that is acting as a Mo source. We tried increasing the inner gap to decrease interaction with the limiter (shot 14) but this did not seem to help at all. The 8T shots, starting with #7, all had the seg1 ef1 currents dropped by 150A to -5850A to compensate for the tf half turns (I_tf=200kA at t=0). I also ran with reduced gas puff (down to 11msec) for all the successful startups. After we got runaways on shot 15 I raised this and got a fizzle. Startup seemed much less robust at 8T than on 1040331. The gas evolution following breakdown showed a strong rise early in the day, then began to pump out after shot 9 or so. Scorecard ---------- Tests 3 Duds 0 Fizzles 3 plasma 10 ====== == Total 16 |
| Session Leader Comments | |||
| Apr 5 2004 08:17:31:380AM | Robert Granetz | MP 371 -- 2 MA operation at 8 T Session leader: R. Granetz/J. Irby Physics operator: S. Wolfe Run Plan: Start the physics run with a repeat of 1040331001 (1.05 MA, 5.5 T, Prf=4 MW) to confirm that TF instrumentation is all working. When ready, load shot 1040331006 (1.05 MA, 8.0 T) from last week. (Set PLC TF limit at 235 kA and TF start at t=-1.5 s). Raise Ip in 0.2 MA increments, while also raising the A-coil current and the PLC OH/EF limits appropriately. (Session leaders will specify the desired A-coil current for each shot.) We want RF heating in order to help with OH flux budget, but if it introduces lots of impurities, we may want to rethink this. | |
| Apr 5 2004 12:08:14:953PM | 1040405009 | Robert Granetz | Shot 09 -- Plasma. 1 MA, 8 T, full length, Prf=4.0-2.0 MW. First good shot of the miniproposal. Next shot: go to 1.2 MA |
| Apr 5 2004 12:41:35:803PM | 1040405010 | Robert Granetz | Shot 10 -- Plasma. Good shot. 1.2 MA, 8 T, full length, Prf= ~3 MW. About 0.5-0.7 keV of heating on the GPC. A-coil current is 1500 A (programmed for 2000 A in PCS). Next shot: go to 1.4 MA; raise A-coil current by 500 A |
| Apr 5 2004 01:08:00:813PM | 1040405011 | Robert Granetz | Shot 11 -- Plasma. Disrupted at t=1.11 s. I_halo_L=110 kA, I_halo_U=50 kA. 1.4 MA, 7.9 T. There are a number of moly injections which undoubtedly caused the disruption. (Some can be seen on the video.) No locked mode. Prf=4.5 MW, nice waveform. Next shot: increase inboard gap by 5 mm. |
| Apr 5 2004 04:08:59:823PM | 1040405014 | Robert Granetz | Shot 14 -- Plasma. Disrupted at t=1.06 s. I_halo_L=140 kA, I_halo_U=50 kA. 1.4 MA, 7.9 T. Looks the same as shot 11. No locked mode. Prf=4.5 MW. Next shot: try turning off the RF, on the hunch that it might be producing impurity injections. Also raise the density a little. |
| Physics Operator Comments | |||
| Apr 5 2004 07:00:03:590AM | Steve Wolfe | Setting up pcs for 1040405 Load from 1040331001 - 1MA 5.4T fiducial-like We'll run this until we're ready to go to 8T, then load 1040331006 and raise current from there. Load at 5-Apr-2004 06:59:52.00 Open tree /home/wolfe/pcs_scratch -1 Open tree done | |
| Apr 5 2004 09:04:16:843AM | 1040405001 | Steve Wolfe | Shot#1: Low power PLC power system test. Power systems ok. Magnetics data didn't come through. Tom's looking into it. |
| Apr 5 2004 09:22:23:793AM | 1040405002 | Steve Wolfe | Shot#2: fizzle next shot: raise Br0 by .5mT, decrease pg4 |
| Apr 5 2004 09:34:56:843AM | 1040405003 | Steve Wolfe | Shot#3: raise Br0 by .5mT to .0005, decrease pg4 from 15->13ms plasma full length. H-mode at .618, rf is pretty ratty. next shot: repeat |
| Apr 5 2004 09:49:37:087AM | 1040405004 | Steve Wolfe | Shot#4: repeat plasma full length, longer H-mode RF still having trouble, only D is on full pulse. next shot:put in a back porch on TF |
| Apr 5 2004 10:05:14:907AM | 1040405005 | Steve Wolfe | Shot#5: repeat with a .75 sec back porch on TF (checking on a high tf scanner reading) plasma full length, short H-mode. next shot: go on up to 8T (1040331006) |
| Apr 5 2004 10:23:59:217AM | 1040405006 | Steve Wolfe | Shot#6: go on up to 8T- Import seg2 from 1040331006, copy tf trace into seg1, enable pg2 (b-side upper) and increase pg2 to 10msec touch wires 11,13,15 to get rid of timestamp warning. fizzle, gas came up. Looks similar to shot#2. next shot: drop pg4, drop ef1's by 150A |
| Apr 5 2004 11:05:59:970AM | 1040405007 | Steve Wolfe | Shot#7: drop pg4 to 11msec, drop ef1's by 150A to -5850 plasma disrupted 1.2 sec -- tf crowbarred before the disruption, around 1.05sc crowbars on ef1l as well at 1.068, tf came first at 1.063; then all the other pf's later at 1.2. Lots of fuse inspections before the next pulse |
| Apr 5 2004 11:51:41:930AM | 1040405008 | Steve Wolfe | Shot#8: tf plc test 50kA next shot: repeat 1MA, try to keep the power supply on this time. |
| Apr 5 2004 12:11:11:883PM | 1040405009 | Steve Wolfe | Shot#9: repeat 1MA, try to keep the power supply on this time. plasma full length, tf breakers pulled after the shot. TF started to rampdown at 1.37sec next shot: go to 1.2MA |
| Apr 5 2004 12:32:38:460PM | 1040405010 | Steve Wolfe | Shot#10: go to 1.2MA, extend RF pulse to 1.5sec plasma full length, tf breakers pulled again. next shot: 1.4MA, drop tf to 220kA (7.9 T), increase acoil current |
| Apr 5 2004 01:05:51:323PM | 1040405011 | Steve Wolfe | Shot#11:1.4MA (program 1.45), drop tf to 220kA (7.9 T), increase acoil current to 2500A plasma disrupted at 1.11sec; looks like a series of injections Looks like some interaction on inner wall, although gap is 1cm next shot: increase clearin by 5mm |
| Apr 5 2004 02:04:45:900PM | 1040405011 | Steve Wolfe | There will be a delay of about 1 Hour while the engineers set up a test on one of the tf power supplies. |
| Apr 5 2004 02:48:22:420PM | 1040405011 | Steve Wolfe | There will be a further nalf-hour delay while the engineers replave several gate drive boards in the TF supply. |
| Apr 5 2004 03:30:02:890PM | 1040405012 | Steve Wolfe | Shot#12: increase clearin by 5mm, rcur by 2.5mm; flatten zxu (.02 to .04 at EOF) NOTE: Alternator dropping rotation back to 1703 from 1718rpm. Shot 12 will be a tf test at 50kA. 50kA test ok. next shot: reload shot#3 from today for a 5.4T plasma |
| Apr 5 2004 03:44:18:270PM | 1040405013 | Steve Wolfe | Shot#13: reload shot#3 from today for a 5.4T plasma, just to see. plasma full length, lots of little H-modes, almost lost it vertically in late rampdown. No TF or alternator problems. next shot: Back to 8T, 1.4MA |
| Apr 5 2004 04:05:01:350PM | 1040405014 | Steve Wolfe | Shot#14: reload shot#12, programmed for increase clearin by 5mm, rcur by 2.5mm; flatten zxu (.02 to .04 at EOF) plasma disrupted at 1.07sec, big injections/radiation. next shot: repeat with RF off. |
| Apr 5 2004 04:35:25:820PM | 1040405015 | Steve Wolfe | Shot#15: repeat with RF off, oh supply limits raised to -33kA each. raise nl04 to 1.0e20 disrupted at .55 ; tci feedback seems to have broken. also runaways. next shot: decrease rate of rise of nl04. |
| Apr 5 2004 04:55:22:363PM | 1040405016 | Steve Wolfe | Shot#16: decrease rate of rise of nl04. increase pg4 to 14msec Also turn off He3 puff. fizzle. Raised the gas too much. END OF RUN |
| Engineering Operator Comments | ||||
| Shot | Time | Type | Status | Comment |
| 1 | 08:59:21:447AM | Test | Ok | Power system low power test |
| 2 | 09:15:54:470AM | Plasma | Ok | |
| 3 | 09:28:36:617AM | Plasma | Ok | |
| 4 | 09:42:03:030AM | Plasma | Ok | |
| 5 | 09:56:45:440AM | Plasma | Ok | |
| 6 | 10:15:38:843AM | Plasma | Ok | |
| 7 | 10:47:52:270AM | Plasma | Bad | tf fault |
| 8 | 11:49:02:113AM | Test | Ok | tf 50ka plc test |
| 9 | 12:01:48:837PM | Plasma | Ok | |
| 10 | 12:27:35:280PM | Plasma | Ok | |
| 11 | 12:51:40:007PM | Plasma | Bad | tf fault |
| 12 | 03:26:34:320PM | Test | Ok | 50 KA TF test |
| 13 | 03:36:50:307PM | Plasma | Ok | |
| 14 | 03:52:02:347PM | Plasma | Bad | tf fault |
| 15 | 04:28:02:760PM | Plasma | Ok | |
| 16 | 04:52:28:873PM | Plasma | Ok | |