| Miniproposals | ||||||||||
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| Operators | |
| Session leader(s): | John Liptac |
| Physics operator(s): | Ron Parker,Steve Wolfe,Ron Parker |
| Engineering operator(s): | Andy Pfeiffer,Bill Parkin,Gary Dekow |
| Engineering Operator Run Comment |
| MP#418 LH Coupling studies SL: Liptac/Parker PO: Parker |
| Session Leader Plans |
| Entered: Apr 12 2006 04:26:10:180PM |
| Author: John Liptac |
| Run Plan 1060406 LH Protection System Testing and Conditioning
Goals: 1. Test new protection scheme. 2. If protection is working increase power and condition system. Plasma Conditions: Same type of plasmas 1060310. Low density L-mode, lower single null, nl_04~0.6, B0=5.4 T, and Ip~ 700kA. No ICRF during LH pulses. Load shot 1060310024. LH setup: Begin with the launcher at 1595 counts ~1mm behind limiter. Set mechanical phase shifters to 90 degree CD phasing. Shot 1: two segments, 90 CD phasing. LH power at 0.695 s. 20kW/klystron. Setpoint generator settings: Shot Length=110 ms, Duty Cycle=9.1%, Pulse Period=55 ms. Increase power in 5-10kW/klystron increments until arc is observed. If system recovers for second pulse, then contract time between pulses to measure the needed recovery time. If system seems to be working increase power and try to build upon results from run 1060310. |
| Physics Operators Plans |
| Entered: Apr 12 2006 04:42:16:723PM |
| Author: Ron Parker |
| Physop Plan and Engineering Setup for Thursday, April 13
MP#418 LH Coupling studies SL: Liptac/Parker PO: Parker ECDC overnight in D2 at 2.e-4 Torr Power systems as on 1060406001 A-coil configuration: normal [+Dtop -Dbot -Jtop +Jbot] and enabled. C-coil Start=0.3sec, Invert=2.0sec NO ICRF Gas Setup: ---------- fill B-top 6psi D2 Hybrid enabled (PG4) fill B-side lower 1 psi Argon Hybrid Disabled (PG1) fill B-side Upper as is, Hybrid Disabled (PG2) fill B-main 40psi D2 Hybrid Enabled (PG3) NINJA: 12psi D2 Enable ECE, VUV, Z-bolo shutter assuming no vacuum problems Run Plan We will be runnning low density discharges to continue LH coupling studies with a goal of increasing power and pulse length. The plasmas will be standard L-mode discharges with ne_l(04)~ 0.5e20 m-2, BT = 5.4 T and Ip ~ 700 kA. We hope to demonstrate effective performance of the Coupler Protecttion System, based on the reflection coeficient measurements at the Intermediate Couplers. In addition, we will be testing the feasibility of a restrike system in the event of shut down by the CPS system. |
| Session Leader Summaries |
| Entered: Apr 13 2006 07:50:43:467PM |
| Author: John Liptac |
| The protection system was tested and seems to provide a level of protection, but is not sufficient for long pulse, high power, operation. Looking at increases in reflected power looks promising as a means of protection, but needs to be extended to monitor all the of the jungle gym couplers to reach long pulse lengths. Restrike was also tested and seemed to work, as several faults during pulses caused trips, but were restarted 20 ms later as desired. Towards the end of the run the pulse length was extended to 105 ms. The previous best was 20 ms. No conclusive evidence of current drive was observed, although strong signals on the HXR camera and ECE diagnostic indicate the presence of fast electrons.
The run began with using six segments of 5 ms. The power was increased in 10 kW/klystron increments until 80 kW/klystron was reached. At this level a body current fault was reached on klystron 9. It was decided to lower the power level and increase the pulse length. Beginning with about shot 14 with a power level of 70 kW/klystron a periodic signal was observed on the jungle gym couplers and RINT signals of klystron 5. This problem was intermittent throughout the day. It is not certain what it is and if it is benign or not. At times it would be observed on klystron 4 as well. Shots 13 and 14 produced large HXR and ECE signals. On 15 the power level was reduced to 60 kW/klystron to try and get rid of the periodic signal. A two segment ramp was used on shots 17-31 as the power level, and phase were varied as the pulse length was incrementally increased. The LH system responded very well and a pulse length of 105 ms at ~50kW/klystron was reached on shot 31. Shot 31 had 210 ms of total klystron operation. |
| Physics Operator Summaries |
| Session Leader Comments | |||
| Apr 13 2006 09:42:26:207AM | 1060413001 | John Liptac | Begin with 30 kW/klystron and 90 degree CD phasing. Grill position about 1 mm behind limiter at ~1595 counts.
Use six 5 ms pulses every 50ms begining at 0.7s. Made it through all six segments just fine, no arcs and low reflection. RINT04 seems to not be working, signal is at a very low level. Increase power on next shot. |
| Apr 13 2006 09:42:36:737AM | 1060413002 | John Liptac | 40 kW/klystron and 90 degree CD phasing.
Use six 5 ms pulses every 50ms begining at 0.7s. Made it through all segments with low reflection coef. Continue to increase power at short pulse length. |
| Apr 13 2006 09:49:05:283AM | 1060413003 | John Liptac | 50 kW/klystron and 90 degree CD phasing.
Use six 5 ms pulses every 50ms begining at 0.7s. Made it through all segments again. RINT power on klystrons 8 and 9 is ~10%, still well below the 30% trip level. Would like to see the protection system work before extending the pulse length, so continue to increase the power. The density is starting to get a little low, try and increase a bit. |
| Apr 13 2006 10:09:08:250AM | 1060413004 | John Liptac | 60 kW/klystron and 90 degree CD phasing.
Use six 5 ms pulses every 50ms begining at 0.7s. Made it through all six segments again. Reflection coefs. seem to go down slightly with increasing density. |
| Apr 13 2006 10:19:57:753AM | 1060413005 | John Liptac | 70 kW/klystron and 90 degree CD phasing.
Use six 5 ms pulses every 50ms begining at 0.7s. Again no signs of arcing. RINT 8 ~11%. Getting good signal on HXR and ECE. |
| Apr 13 2006 10:55:31:143AM | 1060413006 | John Liptac | 80 kW/klystron and 90 degree CD phasing.
Use six 5 ms pulses every 50ms begining at 0.7s. Body current fault on cart 3 (klystron 9). No arcs present. Go down in power and try again. |
| Apr 13 2006 11:11:41:207AM | 1060413007 | John Liptac | 70 kW/klystron and 90 degree CD phasing.
Use six 5 ms pulses every 50ms begining at 0.7s. Arc on klystron 10 segment 1. Protection worked and restart worked so got the remaining 5 segments. Stay at this power level for now to avoid the body current issue and work on extending the pulse length. |
| Apr 13 2006 11:15:37:330AM | 1060413008 | John Liptac | 70 kW/klystron and 90 degree CD phasing.
Use two 10 ms pulses every 200 ms begining at 0.695s. Disruption at ~0.55 s. Try same set up again. |
| Apr 13 2006 11:36:36:190AM | 1060413009 | John Liptac | 70 kW/klystron and 90 degree CD phasing.
Use two 10 ms pulses every 200 ms begining at 0.695 s. Plasma went and so did LH. RINT powers look good, max is still number 8 with ~7 kW while the FINT had ~64 kW. Increase pulse length by another 5 ms. |
| Apr 13 2006 11:45:52:550AM | 1060413010 | John Liptac | 70 kW/klystron and 90 degree CD phasing.
Use two 15 ms pulses every 200 ms begining at 0.695 s. Ran well. Increase by another 5 ms. |
| Apr 13 2006 12:00:49:703PM | 1060413011 | John Liptac | 70 kW/klystron and 90 degree CD phasing.
Use two 20 ms pulses every 200 ms begining at 0.695 s. Ran well. Another 5 ms. |
| Apr 13 2006 12:11:48:597PM | 1060413012 | John Liptac | 70 kW/klystron and 90 degree CD phasing.
Use two 25 ms pulses every 200 ms begining at 0.695 s. Running smoothly. Keep it going. |
| Apr 13 2006 12:55:36:940PM | 1060413014 | John Liptac | 70 kW/klystron and 90 degree CD phasing.
Use two 40 ms pulses every 200 ms begining at 0.695 s. Klystron #5 jungle gym couplers show high, periodic, reflections. Values were approaching 85% relflection. Flash observed in frame 15 on the LH camera, which is centered on the waveguides 1-12 half of the coupler. Decrease power. |
| Apr 13 2006 01:13:23:173PM | 1060413015 | John Liptac | 60 kW/klystron and 90 degree CD phasing.
Use two 40 ms pulses every 200 ms begining at 0.695 s. Observed klystron #5 problems, jungle gym couplers show high, periodic, reflections on segment 1. Segment 2 seems ok. |
| Apr 13 2006 01:24:39:300PM | 1060413016 | John Liptac | 40-80 kW/klystron and 90 degree CD phasing.
Use two 40 ms pulses every 200 ms begining at 0.695 s. Should put first segment at 40kW and second at 60kW. The ramp seemed to fix the issue in klystron 5, segment 1. Continue to increase pulse length. |
| Apr 13 2006 01:42:19:190PM | 1060413017 | John Liptac | 40-80 kW/klystron and 90 degree CD phasing.
Use two 45 ms pulses every 200 ms begining at 0.695 s. Should put first segment at 40kW and second at 60kW. Still ok, increase length. |
| Apr 13 2006 01:58:35:267PM | 1060413018 | John Liptac | 40-80 kW/klystron and 90 degree CD phasing.
Use two 50 ms pulses every 200 ms begining at 0.695 s. Should put first segment at 40kW and second at 60kW. Arc protection worked, first segment turned off on startup then restarted 20 ms later as desired. Klystron 10's power was really low on startup. See periodic structure in relected power on klystrons 4 and 5 in the jungle gym couplers. |
| Apr 13 2006 02:02:46:707PM | 1060413019 | John Liptac | 40-80 kW/klystron and 90 degree CD phasing.
Use two 50 ms pulses every 200 ms begining at 0.695 s. Should put first segment at 40kW and second at 60kW. Repeat shot 18. Seemed to go ok this time. No fault on segment one or two. RINTS seem to be ok too. |
| Apr 13 2006 02:31:53:330PM | 1060413021 | John Liptac | 40-80 kW/klystron and 120 degree CD phasing.
Use two 55 ms pulses every 200 ms begining at 0.695 s. Should put first segment at 40kW and second at 60kW. Change phase and see if behavior changes. Tripped out during second segment, klystron 9, and restarted. The RINT for klystron 7 seems to be coming up at the end of the second segment, but does not trip. Repeat and try to condition. |
| Apr 13 2006 02:50:24:423PM | 1060413022 | John Liptac | 40-80 kW/klystron and 120 degree CD phasing.
Use two 55 ms pulses every 200 ms begining at 0.695 s. Should put first segment at 40kW and second at 60kW. Made it to 0.924 s in segment 2 before tripping out. Klystron 9 is the culprit again. Klystron 7 looked ok. Try it one more time. |
| Apr 13 2006 03:08:38:830PM | 1060413023 | John Liptac | 40-80 kW/klystron and 120 degree CD phasing.
Use two 55 ms pulses every 200 ms begining at 0.695 s. Should put first segment at 40kW and second at 60kW. Worse than shot 22. Lower the power and try again. |
| Apr 13 2006 03:17:18:767PM | 1060413024 | John Liptac | 40-60 kW/klystron and 120 degree CD phasing.
Use two 55 ms pulses every 200 ms begining at 0.695 s. Should put first segment at 40kW and second at 50kW. Got about 30 and 40 kW for each segment on the ramp. Shot went ok. Change the phase. |
| Apr 13 2006 03:32:26:873PM | 1060413025 | John Liptac | 40-60 kW/klystron and 60 degree CD phasing.
Use two 55 ms pulses every 200 ms begining at 0.695 s. Should put first segment at 40kW and second at 50kW. Got about 30 and 40 kW for each segment on the ramp. No faults. X-rays seem softer. |
| Apr 13 2006 03:45:36:060PM | 1060413026 | John Liptac | 40-60 kW/klystron and 90 degree CD phasing.
Use two 55 ms pulses every 200 ms begining at 0.695 s. Should put first segment at 40kW and second at 50kW. Got about 30 and 40 kW for each segment on the ramp. Fault on first segment, but restarted and the second segment ran ok. |
| Apr 13 2006 04:13:21:670PM | 1060413027 | John Liptac | 40-60 kW/klystron and 90 degree CD phasing.
Use two 65 ms pulses every 200 ms begining at 0.695 s. Should put first segment at 40kW and second at 50kW. See the periodic oscillation on klystrons 4 and 5 during the second segment. Drop power on #4 by 10 kW and increase pulse length. |
| Apr 13 2006 04:25:06:390PM | 1060413028 | John Liptac | 40-60 kW/klystron and 90 degree CD phasing.
Use two 75 ms pulses every 200 ms begining at 0.695 s. Should put first segment at 40kW and second at 50kW. Oscillations have gone away. Increase pulse length. |
| Apr 13 2006 04:39:46:750PM | 1060413028 | John Liptac | 40-60 kW/klystron and 90 degree CD phasing.
Use two 75 ms pulses every 200 ms begining at 0.695 s. Should put first segment at 40kW and second at 50kW. Oscillations have gone away. Increase pulse length |
| Apr 13 2006 04:37:55:450PM | 1060413029 | John Liptac | 40-60 kW/klystron and 90 degree CD phasing.
Use two 85 ms pulses every 200 ms begining at 0.695 s. Should put first segment at 40kW and second at 50kW. Ran well. |
| Apr 13 2006 05:00:49:077PM | 1060413031 | John Liptac | 40-60 kW/klystron and 90 degree CD phasing.
Use two 105 ms pulses every 200 ms begining at 0.695 s. Should put first segment at 40kW and second at 50kW. Ran just fine. |
| Physics Operator Comments | |||
| Apr 13 2006 09:05:25:410AM | 1060413001 | Ron Parker | April 13, 2006. LH run, object to increase power and pulse length.
Cell access to stabilize interferometer, maybe short delay. Still a problem, we'll run on Z-meter feedback for density. Shot 1 coming up. |
| Apr 13 2006 09:25:01:550AM | 1060413001 | Ron Parker | Shot 1 was OK, LH power at 30 kW/klystron, 6 pulses |
| Apr 13 2006 09:37:55:300AM | 1060413002 | Ron Parker | Shot 2 ran OK. LH klystron power 35-40 kW @ FINTs |
| Apr 13 2006 09:51:13:923AM | 1060413003 | Ron Parker | Shot 3 ran well. Density is a bit too low, increase on next shot.
Klystron power ~ 45 kW-50 kW/klystron, still 6 pulses, 5 ms width. |
| Apr 13 2006 10:02:45:050AM | 1060413004 | Ron Parker | Shot 4 ran well, ~ 60 kW/klystron. so far, so good.
Increase to 70 kW on next shot. |
| Apr 13 2006 10:24:12:690AM | 1060413005 | Ron Parker | Shot 5 ran without hitch. Klystron power ~ 70 kW/tube. |
| Apr 13 2006 10:53:29:033AM | 1060413006 | Ron Parker | Shot 6 ran, but LH tripped out due to body current trip in klystron 9.
Next: rerun @ 70 kW/klystron Steve Wolfe becomes PO until 12:15 |
| Apr 13 2006 10:58:16:393AM | 1060413007 | Steve Wolfe | Shot#7: Ran as programmed. Parker off to class. Wolfe sitting in as physop for an hour or so. Next: No PCS changes |
| Apr 13 2006 11:22:24:923AM | 1060413008 | Steve Wolfe | Shot#8: plasma disrupts at .55sec PF breaker pulled, oh1 crowbar AFTER the disruption. Looks like an injection at .547 Nothing obviously wrong with position. Next: Try again and hope it goes away (and the plasma doesn't) |
| Apr 13 2006 11:29:13:440AM | 1060413009 | Steve Wolfe | Shot#9: Plasma ran as programmed. Next: No pcs changes. Brock will try to shoot a pellet at 1.8sec |
| Apr 13 2006 11:41:47:017AM | 1060413010 | Steve Wolfe | Shot#10: Plasma ran as programmed. No pellet in evidence; they claim the injector fired. Next: No PCS changes |
| Apr 13 2006 11:58:43:067AM | 1060413011 | Steve Wolfe | Shot#11: Plasma ran as programmed. We're getting an early (<0.15s) runaway dump. No pellet in evidence. Next: No PCS changes |
| Apr 13 2006 12:13:24:423PM | 1060413012 | Steve Wolfe | Shot#12: plasma ran as programmed. Brock got a pellet that time. We're definitely seeing response on ECE and fast EFIT Parker's back |
| Apr 13 2006 12:25:43:567PM | 1060413013 | Ron Parker | Parker back as PO.
Shot 13 ran OK. Continuing to extend pulse width. |
| Apr 13 2006 12:56:01:673PM | 1060413014 | Ron Parker | Shot 14 ran OK, but breakdown problems in WGs 9&10. Reduce power for next shot. |
| Apr 13 2006 01:14:31:987PM | 1060413015 | Ron Parker | Shot 15 ran, still breakdown in 9&10. Continue to reduce power |
| Apr 13 2006 01:27:22:160PM | 1060413016 | Ron Parker | Shot 16 ran OK. RF did not appear to breakdown. |
| Apr 13 2006 01:55:23:753PM | 1060413017 | Ron Parker | Shot 17 was OK. RF did not appear to breakdown. Continue to extend pulse width to 50 ms and somewhat higher power (2 pulses, 2nd pulse ~ 60 kW +) |
| Apr 13 2006 01:54:33:660PM | 1060413018 | Ron Parker | Shot 18 ran OK. RF tripped on first pulse, but went on retry. However, second pulse looked had problems in WG 8, klystron 4. |
| Apr 13 2006 02:15:16:940PM | 1060413019 | Ron Parker | Shot 19 ran, and RF OK. |
| Apr 13 2006 02:17:52:080PM | 1060413020 | Ron Parker | Shot 20 ran OK, and RF did not appear to breakdown. |
| Apr 13 2006 02:19:44:173PM | 1060413020 | Ron Parker | Shot 20 ran, and RF OK.
Next: Try 120 phasing (from 90) |
| Apr 13 2006 02:34:08:923PM | 1060413021 | Ron Parker | Shot 21 ran OK. RF tripped on second pulse, now at 120 phasing.
Try again. |
| Apr 13 2006 03:09:47:063PM | 1060413023 | Ron Parker | Shot 23 fired off well. RF still breaking down on 2nd pulse.
Try again, reduce 2nd pulse amplitude by 10 kW |
| Apr 13 2006 03:18:35:690PM | 1060413024 | Ron Parker | Shot 24 went through, both plasma and RF
Next: try 60 degree phasing. |
| Apr 13 2006 03:32:53:093PM | 1060413025 | Ron Parker | Shot 25 ran without hitch. Qualitatively, X-ray spectrum looks less hard than at 120 or 90. Next: Try 90 to verify. |
| Apr 13 2006 03:59:12:390PM | 1060413026 | Ron Parker | Shot 26 ran OK, faulted on first segment, not on second.
Next: Add 10 ms to 90 deg pulse. |
| Apr 13 2006 04:06:34:093PM | 1060413027 | Ron Parker | Shot went OK. RF showed oscillatory reflected power in WG 8. |
| Apr 13 2006 04:30:15:310PM | 1060413028 | Ron Parker | Shot 28 OK. 2nd RF pulse out to 75 ms. Next: Extend to 85 ms. |
| Apr 13 2006 04:31:30:983PM | 1060413029 | Ron Parker | Shot 29 went off OK. RF pulse out to 85 ms. Both pulses OK |
| Apr 13 2006 04:46:55:967PM | 1060413030 | Ron Parker | Shot 30 ran well. LH pulse up to 93 ms on second pulse. No problem.
Last shot: Add 10 more ms. |
| Apr 13 2006 05:33:54:420PM | 1060413031 | Ron Parker | Run 1060413 went very well. The same low density plasma was produced for 31 shots, allowing the lower hybrid system to bring up the power and increase pulse length. Peak pulses of 70 kW per klystron were produced and pulses of slightly over 100 ms duration (last pulse). Both machine and LH system preformed very well. In particular, the protection system based on the reflection coefficients at the forward directional couplers shut down when it should have, and did not shut down when a fault was not indicated. Also the restrike circuit worked well, turning the RF back on after a delay following a fault. It was clear however that a further improvement needs to be made, namely a fault protection strategy based on the reflected power at the 48 "jungle jim" couplers. A lot of data was gathered on X-ray emission as a function of power and phase, so the run was productive from that point of view. Nevertheless, no indication of current drive was observed, and this is worrisome. Modeling of the X-ray data should help in unraveling this puzzle.
The machine ran flawlessly, with 31 shots without a fizzle or dud, and only one disruption (when Parker was in class). All in all, a lot of progress made but a deepening mystery concerning the absence of current drive |
| Engineering Operator Comments | ||||
| Shot | Time | Type | Status | Comment |
| 1 | 09:07:34:877AM | Plasma | Ok | |
| 2 | 09:25:36:393AM | Plasma | Ok | |
| 3 | 09:40:38:643AM | Plasma | Ok | |
| 4 | 09:54:23:440AM | Plasma | Ok | |
| 5 | 10:09:23:580AM | Plasma | Ok | |
| 6 | 10:26:27:957AM | Plasma | Ok | |
| 7 | 10:56:01:783AM | Plasma | Ok | |
| 8 | 11:10:01:690AM | Plasma | Ok | PF breaker opened after disruption |
| 9 | 11:25:01:627AM | Plasma | Ok | |
| 10 | 11:37:41:940AM | Plasma | Ok | |
| 11 | 11:55:25:250AM | Plasma | Ok | |
| 12 | 12:08:45:817PM | Plasma | Ok | |
| 13 | 12:22:31:033PM | Plasma | Ok | |
| 14 | 12:36:56:863PM | Plasma | Ok | |
| 15 | 12:54:17:910PM | Plasma | Ok | |
| 16 | 01:13:00:470PM | Plasma | Ok | |
| 17 | 01:29:50:567PM | Plasma | Ok | |
| 18 | 01:42:23:923PM | Plasma | Ok | |
| 19 | 01:57:35:783PM | Plasma | Ok | |
| 20 | 02:10:10:783PM | Plasma | Ok | |
| 21 | 02:23:33:143PM | Plasma | Ok | |
| 22 | 02:41:23:190PM | Plasma | Ok | |
| 23 | 02:56:08:940PM | Plasma | Ok | |
| 24 | 03:08:42:033PM | Plasma | Ok | |
| 25 | 03:22:14:063PM | Plasma | Ok | |
| 26 | 03:35:03:927PM | Plasma | Ok | |
| 27 | 03:57:47:297PM | Plasma | Ok | |
| 28 | 04:13:57:437PM | Plasma | Ok | |
| 29 | 04:27:40:530PM | Plasma | Ok | |
| 30 | 04:40:12:123PM | Plasma | Ok | |
| 31 | 04:52:52:437PM | Plasma | Ok | |