Miniproposals

Miniproposal: Date Filed: Title: First Author: Session Leader: Steve Wukitch (shots 1-11)

Engineering Operator Run Comment

MP268 and MP282A or MP248 sl:wukitch, PO:wolfe, EO:dekow/parkin

Session Leader Plans

Physics Operators Plans

Session Leader Summaries

Entered: Jul 7 2004 03:49:24:993PM

Author: To Be Determined

Run Plan for Tuesday, Oct 3, 2000 Experiments SL ------------- ---- Engineering tests Irby/Gwinn MP#268 ICRF Wukitch/Boivin followed by MP#282A Current Ramp/peeling Mossessian OR MP#248 High Performance [g] PO: Wolfe Plan (such as it is) -------------------- The run will start with Engineering Tests to diagnose the cause of the ground faults which terminated the run last Friday. These tests will be under the direction of Irby and Gwinn. 1. Measure loading as a function of power comparing D, E, and J-port. (1 shot) 2. Measure J, D, and E-port heating efficiency up to 1.5 MW each - L-mode required. (3 shots) 3. In L-mode and diverted plasmas, verify simultaneous operational capability of D, E, and J-port antennas. (2 shots) 4. Evaluation of maximum reliable power from J-port, and maximum total power from D, E, and J 5. Assuming total achievable power exceeds 3MW, determination of H-mode accessibility for upper-null targets; this will indicate whether we will do reverse the field for next week. Again depending on the results of the ICRF evaluation, and on time remaining, we will proceed with either MP#282A (current ramps), MP#248 (H-mode performance at high P_rf), or else punt the run and return J-port to a two-strap configuration. Engineering Setup ------------------ New ground fault diagnostics should be installed, tested and ready before attempting plasma shots. We will presumably need PLC test shots for at least the OH and TF supplies (separately). Once we decide to go to plasma shots: Power systems as on 1000929019 Gas System Setup: Gas setup fill B-top with 6 psi of D2 Hybrid enabled fill B-side lower with 1 psi of Ar Hybrid DISABLED fill B-side upper with 35 psi of D2 Hybrid DISABLED, for ECDC fill C-side with 30 psi of D2 Hybrid enabled The following gate valves should be enabled: ECE, VUV 006 plasma attempt RF request: D-port 1.5 MW 1.2-1.45 sec E-port 1.5 MW 0.55-0.8 sec J-port 0 0.85-1.15 sec result: plasma upper null D-port 1.5 MW 1.2-1.45 sec E-port 0 MW 0.55-0.8 sec - no gate J-port 0 0.85-1.15 sec 007 plasma attempt RF request: D-port 1.5 MW 1.2-1.45 sec E-port 1.5 MW 0.55-0.8 sec J-port 1.5 0.85-1.15 sec result: plasma, upper null, early disruption ~0.65 sec D-port 0 MW 1.2-1.45 sec E-port 1.5 MW 0.55-0.65 sec J-port 0 0.85-1.15 sec 008 plasma attempt with more gap BT~ 5.2 T Ip~ 0.8 MA RF request: D-port 1.3 MW 1.2-1.45 sec E-port 1.3 MW 0.6-0.85 sec J-port 1.3 MW 0.9-1.15 sec result: plasma, upper null, D-port MW 1.2-1.45 sec E-port MW 0.55-0.65 sec J-porT MW 0.85-1.15 sec 009 plasma attempt RF request: D-port 1.3 MW 1.2-1.45 sec E-port 1.3 MW 0.6-0.85 sec J-port 1.3 MW 0.9-1.15 sec [0,pi,0,pi] result: plasma upper null D-port 1.3 MW 1.2-1.45 sec - phase balance fault (HiYard) E-port 1.3 MW 0.6-0.85 sec J-port 1.3 MW 0.9-1.15 sec We have had a consistent injection with E-port that killed the first plasma and is getting smaller over the last 3 shots. 010 PF breaker We began the day with power system preparation and testing (see physop summary for details). FMIT#3's FPA xbar trigger circuit failed after the initial morning startup. A capacitor failed and was replaced. The trigger circuit was tested and declared ready for operation. FMIT#2 did not operate on its first shot and the transmitter was tested into dummy load before the next shot. We managed 2/3 of the comparison on shot 009; FMIT#1 failed because of a high yard fault. The J-port heats as well as E-port which is somewhat different from 1000929 where J-port appeared to heat better. Quantitative estimates of heating efficiency sawtooth reheat can be made from this shot. We are still in search of a good comparison discharge and completing the operational testing of J-port.

Physics Operator Summaries

Entered: Jul 7 2004 04:37:12:190PM

Author: To Be Determined

Physics Operator Summary for Tuesday, Oct 3, 2000 PO: Wolfe EO: Dekow,Parkin SL: Irby; Wukitch Nominal MP: #268 ICRF (J-port) Several changes have been made to the power system instrumentation and ground configuration in order to identify the source of the ground faults which occurred last Friday. New ground fault current transformers have been installed on the structure ground and the junction of the vessel ground leads. A rogowski has been installed to monitor the net current in the OH2L bus. A 150 Ohm resistor has been installed in the OH2L ground leg, and a voltage monitor from the bus side of the resistor to ground has been temporarily wired into the former EF1L bus voltage signal. As a result of casualties of yesterday's hipots, four tf voltage taps and the fast tf tap instrumentation have been removed. We started with a series of plc-controlled power system tests, on tf, oh's, and ef2. All went through successfully, except we had to run a couple of no-power tests due to various data system glitches. There was also a delay before the oh test to allow the new rogowski, which links both oh2l busses, to be installed. The rf group used the time to fix a power supply on the j3 crowbar circuit. Contrary to the published run plan, the session leader requested that we start with upper null plasmas, like 1000929018, to provide an l-mode target for all three antennas firing individually. The plasma shots were #6-10, all upper null. There were some problems with each antenna, and we never actually got all three to stay on for the full programmed pulses; however, it did appear that the efficiency of J at 1.3MW was quite similar to that of the dipoles. Shot 10 exhibited a -2000V spike on the oh2l grounding resistor at 21msec, which is the same time (within 2msec) as the gf fuse blowing on 1000929015 and 1000929020. The oh2l common mode rogowski seemed to confirm a "missing" current of order several 100A, but the gf pearson signal was in the opposite direction. Spikes of order ~10^3 V were also seen on other bus voltage signals; these may well be due to common mode problems, since they are all in the same cabinet, and mostly (all?) on the same L8212 digitizer. Tests after the run confirmed that the sign of the pearson current and resistor voltage on shot 10 were inconsistent; see shot 11, and also engineering test #2541, which show + voltage corresponding to + current indication, contrary to what is seen on shot 10. The duration of the voltage spike is only ~1msec, despite the fact that the gf fuse does not blow, so there is no reason for the ground current to clear. Shot 10 also ended in an early (.57sec) disruption, which seemed to be due to an injection unrelated to (prior to) the rf. There is also a -300V spike on the oh2l resistor some time after the disruption, which caused an oh1 crowbar. There seems to be no reason to believe that the disruption was causally related to the ground current. The run was stopped to allow time to consider the meaning of these measurements and decide how to proceed. Scorecard: --------- Tests 6 Duds 0 fizzles 0 plasmas 5 ======= == shots 11

Session Leader Comments
Oct 3 2000 01:28:19:403PM	1001003006	Steve Wukitch	006 plasma attempt RF request: D-port 1.5 MW 1.2-1.45 sec E-port 1.5 MW 0.55-0.8 sec J-port 0 0.85-1.15 sec result: plasma upper null D-port 1.5 MW 1.2-1.45 sec E-port 0 MW 0.55-0.8 sec - no gate J-port 0 0.85-1.15 sec
Oct 3 2000 01:27:54:903PM	1001003007	Steve Wukitch	007 plasma attempt RF request: D-port 1.5 MW 1.2-1.45 sec E-port 1.5 MW 0.55-0.8 sec J-port 1.5 0.85-1.15 sec result: plasma, upper null, early disruption ~0.65 sec D-port 0 MW 1.2-1.45 sec E-port 1.5 MW 0.55-0.65 sec J-port 0 0.85-1.15 sec

Physics Operator Comments
Oct 3 2000 07:16:21:373AM		Steve Wolfe	Run Plan for Tuesday, Oct 3, 2000 Experiments SL ------------- ---- Engineering tests Irby/Gwinn MP#268 ICRF Wukitch/Boivin followed by MP#282A Current Ramp/peeling Mossessian OR MP#248 High Performance [g] PO: Wolfe Plan (such as it is) -------------------- he run will start with Engineering Tests to diagnose the cause of the ground faults which terminated the run last Friday. These tests will be under the direction of Irby and Gwinn. Assuming the satisfactory completion of these tests, we will continue Friday's ICRF experiments, aimed at evaluating the latest J-port four-strap configuration. Major items remaining in this experiment include: 1) Heating of lower SN plasmas, in H-mode 2) Evaluation of maximum reliable power from J-port, and maximum total power from J, D, and E 3) Assuming total achievable power exceeds 3MW, determination of H-mode accessibility for upper-null targets; this will indicate whether we will reverse the field for next week. Again depending on the results of the ICRF evaluation, and on time remaining, we will proceed with either MP#282A (current ramps), MP#248 (H-mode performance at high P_rf), or else punt the run and return J-port to a two-strap configuration. Engineering Setup ------------------ Overnight ECDC in D2, if possible, stopping 2 hours before the run, or as needed for access to the bus work. New ground fault diagnostics should be installed, tested and ready before attempting plasma shots. We will presumably need PLC test shots for at least the OH and TF supplies (separately). Once we decide to go to plasma shots: Power systems as on 1000929019 Gas System Setup: Gas setup fill B-top with 6 psi of D2 Hybrid enabled fill B-side lower with 1 psi of Ar Hybrid DISABLED fill B-side upper with 35 psi of D2 Hybrid DISABLED, for ECDC fill C-side with 30 psi of D2 Hybrid enabled The following gate valves should be enabled: ECE, VUV
Oct 3 2000 07:20:05:653AM		Steve Wolfe	Reload last shot from Friday (current pcs model) coldstart at 7:18 All matrices respond, no errors
Oct 3 2000 07:29:09:687AM		Steve Wolfe	Revised plan: SL Wukitch wants to start with upper null. Switch to segment 3, and reload.
Oct 3 2000 10:50:38:280AM	1001003001	Steve Wolfe	shot#1: No power test. It was supposed to be a 50kA tf test, but the tf resistance/i2t measurement came up in alarm.
Oct 3 2000 11:05:49:233AM	1001003002	Steve Wolfe	shot#2: 50kA tf test ok.
Oct 3 2000 11:47:53:717AM	1001003003	Steve Wolfe	shot#3: EF2 PLC test ok Now we will wait for the OH rogowski, and the RF
Oct 3 2000 12:05:11:797PM	1001003004	Steve Wolfe	shot#4: oh test; the new rogowski is now installed around both OH2L busses. Everything looks ok.
Oct 3 2000 12:20:26:937PM	1001003005	Steve Wolfe	shot#5: Plasma attempt; upper null like 1000929018; enable pcx "beast" for rejean camac init error; bypass igor and run no-power cycle. let's try that again.
Oct 3 2000 01:04:34:903PM	1001003006	Steve Wolfe	shot#6: Plasma attempt; upper null like 1000929018; enable pcx "beast" for rejean have jas disable the dnb tree plasma, full length. d port ran at 1.5MW ok, no E. J wasn't ready. no sign of anomalous signals at 19-21msec on any ground fault trace. There is a 300V spike on the resistor at commutation. Outer gap is around 5mm. H/D 3-5%. It looks like the edge tree got turned off for shot 6; I may have done it accidentally while trying to turn off dnb. Back on for shot 7 next shot: decrease rcur by 2mm to increase outer gap
Oct 3 2000 01:20:54:687PM	1001003007	Steve Wolfe	shot#7: Rcur from .661->.659; j-port should pulse this time. plasma disrupted at .637sec. looks like an injection from e-port? next shot: move early rcur in to .650 to keep it off the outer limiter before it diverts. and decrease rcur another 1.5mm to give the rf more gap.
Oct 3 2000 01:45:27:857PM	1001003008	Steve Wolfe	shot#8: Rcur from .659->.6575 in flattop; .650 early j-port should pulse this time. plasma, full length, but had an injection at .808sec (E-port) all three antennas ran at 1.3-1.4MW j3 faults at 1.07 with a screen xbar; needs something fixed in the power room. comparable heating from each, while they're on. outer gap is ~10mm ground currents still look ok next shot: no pcs changes. try to get all three to run clean
Oct 3 2000 02:13:51:390PM	1001003009	Steve Wolfe	shot#9: repeat. plasma, full length, d-port didn't make it. e and J are prettu clean at 1.3-1.4MW; injection at exactly the same time .808 The spike on the oh2l resistor is now at 2msec, not commutation. next shot: repeat
Oct 3 2000 02:38:40:200PM	1001003010	Steve Wolfe	shot#10: enable b-side lower; otherwise a repeat. disrupted at .565, pf breaker pulled after the disruption; oh1 crowbarred. Injection (or prad anyway) starts at .54 before the rf. There is a spike on the oh2l ground resistor at .654, after the oh1 crowbar, no corresponding current on the pearson. There was also a 2000V spike at 21msec. That looks like our gf problem
Oct 3 2000 03:32:38:233PM	1001003010	Steve Wolfe	There is also a spike at 21msec on the oh2U bus, -400V. Nothing on the OH1 bus volt. The signal in the oh2L gf pearson is +2amp (was negative on Friday). This is inconsistent with the resistor voltage measurement. Need to re-check the instrumentation, including the net current rogowski.
Oct 3 2000 04:25:47:967PM	1001003010	Steve Wolfe	Shot 2541 (engineering test shot). Test of resistor and gf pearson direction. About 2sec period square wave at ~80V on resistor. Positive voltage gives positive current, decays after L/R, then reverses on negative di/dt. Amplitude at peak ~0.4Amp
Oct 3 2000 04:44:00:873PM	1001003011	Steve Wolfe	shot 11: test of gf pearson, resistor and common signal rogowski. 60cycle ~ 2000A on rogowski, 80V on resistor.

Engineering Operator Comments
Shot	Time	Type	Status	Comment
1	10:44:31:903AM	Test	Bad	TF I2T Fault - No Power Test
2	10:56:19:843AM	Test	Ok	TF 50 KA Test
3	11:07:20:077AM	Test	Ok	EF2 PLC Test
4	12:00:46:903PM	Test	Ok	OH PLC Test
5	12:13:46:403PM	Plasma	Bad	Igor Error
6	12:36:13:093PM	Plasma	Ok
7	01:08:52:700PM	Plasma	Ok
8	01:27:21:437PM	Plasma	Ok
9	02:02:05:310PM	Plasma	Ok
10	02:19:23:013PM	Plasma	Bad	OH2U&L comm fault. PF breaker opened.
11	04:36:23:700PM	Test	Ok	Calibration Tests