1. OVERVIEW OF THE DIII–D PROGRAM AND CONSTRUCTION PLANS
Presented by
Peter I. Petersen
for the DIII–D Team
23rd Symposium on Fusion Technology
September Fondazione Cini, Venice, Italy
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2. OUTLINE Advanced Tokamak Internal Coils (I-coils)
Electron Cyclotron System
Plasma Control System
Diagnostics
2005 – 2006 Upgrades
Conclusion
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3. DIII–D CAPABILITIES ALLOW A WIDE RANGE OF RESEARCH AND TECHNOLOGY ISSUES TO BE ADDRESSED
60 different diagnostics
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4. MAIN RESEARCH GOAL FOR DIII–D IS THE ADVANCED TOKAMAK, WHICH INTEGRATES MANY PHYSICS ELEMENTS
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5. TOOLS TO MINIMIZE ERROR FIELDS AND RESISTIVE WALL MODES AT HIGH PLASMA PRESSURE
6 section, external C-coil
12 section, internal I-coil
5 C-supplies kA, 350 V or 7kA at lower voltage tap
4 Switching Power Amplifiers (SPAs) kA, 300 V, ~ s
System must provide for both correction of error fields and feedback stabilization of the RWM.
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6. FLEXIBLE I-COIL POWER SUPPLY CONFIGURATIONS POSSIBLE WITH PATCH PANEL

7. I-COILS PROVIDE A FLEXIBLE SYSTEM FOR ELM CONTROL
N=3 mode
Small islands might be
responsible for the ELM
suppression
Relative small impact on core confinement
Enhance magnetic and
density fluctuations with
no indication of increased
stochasticity
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8. CURRENT ECH SYSTEM ECH System Layout Gyrotron in stand ECH launcher
3 CPI gyrotrons with diamond window, 1 MW 10 s
3 Gycom gyrotrons with boron nitride window, 0.75 MW 2 s
1 MW ECH waveguide
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9. ECCD STABILIZATION OF NEO-CLASSICAL TEARING MODES
Feedback system adjusts q=3/2 surface location to minimize mode amplitude
Active tracking keeps ECCD at the q = 3/2 surface in the absence of the mode
compensates for the Shafranov shift as the plasma pressure b increases
Mode does not reappear when b is raised above the initial stability limit
Stabilization of the 2/1 mode has also been done.
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10. THE LITHIUM BEAM DIAGNOSTIC USES ZEEMAN POLARIZATION SPECTROSCOPY TO MEASURE THE EDGE CURRENT DENSITY
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11. THE UPGRADED BEAM EMISSION SPECTROSCOPY (BES) DIAGNOSTIC BRINGS NEW INSIGHT INTO CORE TURBULENCE AND MHD
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12. MASSIVE GAS PUFF SUCCESFULLY MITIGATES PLASMA DISRUPTIONS
Open jet (Aug. 2003) Directed jet (Mar. 2004) Directed jet w/ reduced
back volume (Oct. 2004)
• Pjet (r=1) ~ 0.04 atm • Pjet (r=1) ~ 0.02 atm • Pjet (r=1) ~ 0.04 atm.
• Fast (~ 1ms) rise time • Slower (~3ms) rise time. • Medium (~ 2ms) rise.
Experiments show significant (2-3x) reduction in halo currents and divertor heat
loads (over VDE disruption).
Large (4x) variation in thermal quench time with gas jet pressure indicates that jet
design plays important role.
No observed runaway electron generation (except in low pressure Ar gas puff).

13. INTEGRATED PLASMA CONTROL IS KEY TO THE DIII–D AT PROGRAM
Real Time Feedback Controlled (Actuator, Sensor)
Long experience: Global parameters and equilibrium
Recent progress: Two-point Te control
Under development: Real-time, multi-point profile control
Te(r,t): ECH, ECE, Thomson scattering
j(r,t): ECCD, MSE …
Te:
ECH,ECE
NTM: ECCD, magnetics
Disruption: Gas jet, magnetics, bolometers
NBI
Plasma b: Paux, RTEFIT
RWM: C-Coil, I-Coil, RTEFIT
Equilibrium: PF-Coils, RTEFIT
Density: Pellet/Cryopumps/Gas valves, CO2 Interferometers

14. FLEXIBLE DIII–D PLASMA CONTROL SYSTEM SUPPORTS INTEGRATED PLASMA CONTROL
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15. PLANNED ECH UPGRADE DURING 2005 - 2006
3 CPI gyrotrons have been purchased
— Delivery scheduled Jul 05 – Jan 06
— Ready for operation in May 06
1 CPI development gyrotron will be available for DIII–D FY05
1 Russian short pulse gyrotron will be available
8 operating gyrotrons might be available in May 06
but only power supplies and transmission lines for 6
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16. LOWER DIVERTOR WILL BE MODIFIED FOR DENSITY CONTROL OF HIGH TRIANGULARITY DOUBLE NULL DIVERTORS
Current configuration
New configuration
double null shape
New configuration
ITER shape
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17. A BEAMLINE REVERSAL IS NECESSARY FOR NEW PHYSICS STUDIES AND IMPROVED PLASMA MEASUREMENTS
QDB regime with central co-rotation
Understanding physics of rotation
Transport barrier control (separate ExB
and Shafranov shift effects)
RWM stability with low rotation
NTM stabilization with modulated rf
Separate Er and J(r) in MSE measurement
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18. OTHER DIII–D UPGRADES Two Cooling Tower (replace old ones)
Beltbus (upgrade to 10 s)
12 audio amplifiers
to stabilize RWMs
2 shown on
this picture
Upgrade 2 Toroidal Field
Circuit Diodes (1 shown)
(upgrade to 10 s)
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19. DIII–D LONG TORUS OPENING ACTIVITIES SCHEDULE
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20. OTHER DIII–D/GA PAPERS
P3C-A-72 OVERVIEW OF THE DIII–D PROGRAM AND CONSTRUCTION PLANS* PETERSEN, P.I.
Selected also for oral presentation O3B-A-72
P3T-B-78 THE UPGRADE OF THE DIII-D EC SYSTEM USING 120 GHZ ITER GYROTRONS CALLIS, R.W.
P3T-B-246 ECH MW-LEVEL CW TRANSMISSION LINE COMPONENTS SUITABLE FOR ITER OLSTAD, R.A
P3C-C-77 HIGH PERFORMANCE INTEGRATED PLASMA CONTROL IN DIII–D* HUMPHREYS, D.A.
P3C-C-79 PROGRESS TOWARDS ACHIEVING PROFILE CONTROL IN THERECENTLY UPGRADED
DIII-D PLASMA CONTROL SYSTEM* PENAFLOR, B.G
P3C-C-149 DIII-D INTEGRATED PLASMA CONTROL TOOLS APPLIED TO NEXT GENERATION TOKAMAKS*
LEUER, J.A
P2C-D-80 REAL-TIME MULTIPLE NETWORKED VIEWER CAPABILITY OFTHE DIII-D EC DATA ACQUISITION
SYSTEM* PONCE, D.
P2T-E-81 OVERVIEW OF THE DIII–D INTERNAL RESISTIVE WALL MODE STABILIZATION POWER SUPPLY
SYSTEM* SZYMANSKI, D.D
P4T-G-71 STRUCTURAL UPGRADE OF IN-VESSEL CONTROL COIL ON DIII D* ANDERSON, P.M.
P2C-D-251 ADVANCES IN REMOTE PARTICIPATION FOR FUSION EXPERIMENTS* SCHISSEL, D.P
Selected also for oral presentation O2B-D-251
P1C-H-467 EVALUATION OF SUPER CRITICAL HELIUM AS A COOLANT FOR DIII-D TYPE
CRYOCONDENSATION BAXI, C.B.,
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