Post on 22-May-2020
Overview of
KSTARInitial Experiments
National Fusion Research InstituteKSTAR Research CenterM. KWON on behalf of KSTAR Team
OV/1-1
KSTAR Team and Collaborators
§ National Fusion Research Institute : YK Oh, WC Kim, HL Yang, JH Kim, SW Yoon, YM Jeon, SH Hahn, HK Na, KR Park, JH Lee, SH Hong, A England, ZY Chen, Y Yaowei, JG Bak, SG Lee, SH Seo, DC Seo, WH Ko, YU Nam, JI Jeong, ST Oh, KD Lee, KI Yoo, BH Park, DK Lee, JC Seol, DS Lee, JW Yoo, H Lee, SW Kim, JG Lee, JS Hong, Y Chu, IS Woo, YO Kim, KP Kim, WS Han, Y Yonekawa, SH Park, MK Park, MK Kim, SI Lee, WL Lee, SH Baek, TG Lee, JS Park, KW Cho, DS Park, J Ju, KM Moon, JS Kim, HS Kim, HK Kim, KM Kim, EN Bang, KS Lee, HT Kim, YM Park, HJ Lee, SW Kwak, NH Song, YB Jang, HT Park, YS Bae, JS Kim, M Joung, SI Park, HJ Do, YS Kim, JH Choi, JK Jin, DG Lee, CH Kim, JD Kong, SR Hong, YJ Kim, ST Kim, NY Jeong, DS Lim, JY Kim, JM Kwon, SS Kim, HG Jang, L Terzolo, SM Lee, S Tokunaga, K. Miki, JC Kim, DR Lee, S Sajjad, I Chavdarovski, JH Sun, L Wang, M LeConte
§ Korea Atomic Energy Research Institute : JG Kwak, SH Jeong, SJ Wang, SH Kim, DH, Chang, BH Oh§ Seoul National University : YS Hwang, YS Na, HS Kim, KM Kim, DH Kim§ Pohang University of Science and Technology : H Park, MH Cho, CM Ryu, W Namkung§ Korea Advanced Institute of Science and Technology : W Choe, CS Chang, SH Lee§ Hanyang University : KS Chung, YH Kim, HJ Woo, JH Sun § Daegu University : OJ Kwon § Soongsil University : CB Kim § Ajou University : SG Oh § Kyungpook University : KW Kim§ University of California at San Diego : P Diamond § Oak Ridge National Laboratory : D Hillis, RJ Colchin (deceased), JW Ahn§ Princeton Plasma Physics Laboratory : D Mueller, L Grisham, JK Park, TS Hahm§ General Atomics : A Hyatt, M Walker, D Humphrey, J Leur, N Eidietis, AS Welander, GL Jackson, J Lohr§ Columbia University : S Sabbagh, YS Park § Fartech : JS Kim, YK In§ Japan Atomic Energy Agency : T Hatae, K Watanabe, M Dairaku, M Kikuchi, K Sakamoto§ National Institute of Fusion Science : K Kawahata, Y Nagayama, K Ida, T Mutoh, B Patterson, N Narihara, T Seki, S Kubo § Kushu University : A Mase, N Yagi§ ASIPP : B Wan, Y Shi§ National Cheng Kung University : F Cheng, K Shaing§ Australian National University : M Hole
Contents
I. INTRODUCTION
II. KSTAR AS A STEADY-STATE DEVICE
• Super-conducting Magnets• Heating & Current Drive• Active Plasma Control• Plasma-Wall Interaction
III. COLLABORATION
IV. FUTURE PLAN
V. SUMMARY
Overview of
KSTARInitial Experiments
I. INTRODUCTION
23rd IAEA Fusion Energy Conference, Daejeon Korea, 11-16 October 2010
►To achieve the superconducting tokamak construction and operation experiences, and
►To develop high performance steady-state operation physics and technologies that are essential for ITER and fusion reactor development
Major radius, R0
Minor radius, a Elongation, kTriangularity, dPlasma volume
Bootstrap Current, fbs
PFC Materials
Plasma shape
Plasma current, IP
Toroidal field, B0
Pulse length
bN
Plasma fuel
Superconductor
Auxiliary heating /CD
Cryogenic
PARAMETERS
1.8 m
0.5 m
2.0
0.8
17.8 m3
> 0.7
C, CFC (W)
DN, SN
2.0 MA
3.5 T
300 s
5.0
H, D
Nb3Sn, NbTi
~ 28 MW
9 kW @4.5K
Designed
1.8 m
0.5 m
2.0
0.8
17.8 m3
-
C
DN
0.5 MA
3.6 T
7 s
> 1.0
H, D, He
Nb3Sn, NbTi
2.0 MW
5 kW @4.5 K
Achieved
KSTAR Parameters
•Black : achieved •Red : by 2010
4
Mission and Achievements
KSTAR Mission
23rd IAEA Fusion Energy Conference, Daejeon Korea, 11-16 October 2010
(a)
5
Advanced
High b, fbs
Long-pulse op.
Advanced Tokamak
Shaping (2010)
H-mode (2011)
bN < 3(2012)
Current profile control (2012)
Wall stabilization (2012)
Transport barrier (2012)
Standard
23rd IAEA Fusion Energy Conference, Daejeon Korea, 11-16 October 2010
CharacteristicTime (sec)
yearplasma performance (βn)
2015
10-3
10-2
10-1
100
101
102
103
104
PFC cooling, Wall inventory
Particle Confinement
Energy Confinement
Disruption, ELM
MHD
Current Diffusion
Erosion
KSTAR OperationWindow
6
Long Pulse Operation
23rd IAEA Fusion Energy Conference, Daejeon Korea, 11-16 October 2010
NBI-180 keV
1 MW, 2 s
NBI-180 keV
1 MW, 2 s
PFC Baking & Cooling200 C
PFC Baking & Cooling200 C
Cryogenic helium supply4.5 K, 600 g/s
Cryogenic helium supply4.5 K, 600 g/s
vacuum pumpingvacuum pumpingECH
84 GHz / 110 GHz0.5 MW, 2 s
ECH84 GHz / 110 GHz
0.5 MW, 2 s
ICRH30 ~ 60 MHz1 MW, 300 s
ICRH30 ~ 60 MHz1 MW, 300 s
KSTAR Device for 2010 Campaign
7
23rd IAEA Fusion Energy Conference, Daejeon Korea, 11-16 October 2010
1st campaign (2008) 2nd campaign (2009)
3rd campaign (2010) 8
KSTAR Device Evolution
Overview of
KSTARInitial Experiments
II. KSTAR AS A STEADY-STATE DEVICE
•Super-conducting Magnets• Heating & Current Drive• Active Plasma Control• Plasma-Wall Interaction
23rd IAEA Fusion Energy Conference, Daejeon Korea, 11-16 October 2010
Date (D/M/Y)
Aug. 6
Aug. 19Temperature (K)
300
250
200
150
100
50
07/8/10 10/8/10 13/8/10 16/8/10 19/8/10
3rd cool-down (2010)1st cool-down (2008)
SC Magnet Cool-down
►1st & 2nd cool-down (2008 / 2009)• Cool-down (from 300 K to 4.5 K) : 21 days (1st ), 31 days (2nd) • All the joints have resistance less than 5 nano-ohm
►3rd cool-down (2010) :• ITER cryogenic system study using KSTAR HRS was conducted in early 2010.
• Cool-down (from 270 K to 4.5 K) : 14 days (from Aug. 6 to Aug. 19)• Total 4700 hours of magnet operation without quench
10
FTP/P6-05, 28
23rd IAEA Fusion Energy Conference, Daejeon Korea, 11-16 October 2010
TF Magnet Operation
11
►The TF magnet system was charged up to 35 kA, producing 3.5 T at the center of the vacuum vessel. The coil temperature increment was less than 0.2 K leaving the margin more than 4 K.
►The measured maximum mechanical stress of the TF structure at 35kA was 152 MPa, which is lower than the operational criteria of 500 MPa and maximum radial displacement from the estimation is less than 0.4 mm.
23rd IAEA Fusion Energy Conference, Daejeon Korea, 11-16 October 2010
PF Magnet Operation
12
►Each PF coil was ramped-up and ramped-down to Max. 10 kA with 1 kA/s, while the temperature increase was approximately 1.5 K .
►At the fast ramp rate (±6 kA, 10 kA/s ramp-up, 100 ms blip ) test for single coil, the temperature increase was 8.7 K mainly due to the AC losses of super-conductors / jackets and the insufficient conditioning to reduce the coupling loss. Conditioning to the full current and optimization of the He distribution circuits will be planned.
23rd IAEA Fusion Energy Conference, Daejeon Korea, 11-16 October 2010 13
Effect of Incoloy on Magnetic Configuration
-0.5 0 0.5
-20
-15
-10
-5
0
5
10
Z[m]
Bz[G
]
-0.5 0 0.5
-10
-8
-6
-4
-2
0
2
4
6
8
10
Z[m]
Br[G
]calculated without incoloy
calculated with incoloy
the measured : + charging
the measured : - charging
BTF=0.1T
BTF=2T
Bz scan by Hall ProbeMulti-spot at field null
Bz exist but Br is negligible
Bz
loop voltage analysis due to up/down asymmetry in
cryostat
0 0.02 0.04 0.06 0.08 0.1
-1.5
-1
-0.5
0
0.5
1
1.5
2
2.5
time[s]
curre
nt[kA
]
I PF1I PF2I PF3I PF4I PF5I PF6I PF7I VV[100kA]
0 0.02 0.04 0.06 0.08 0.1
0
0.5
1
1.5
2
2.5
3
3.5
4
4.5
time[s]
loop v
oltag
e [V]
FL01FL12FL23FL34FL45
Dashed : the calculatedSolid : the measured
Up-down asymmetry!
► Static magnetic field error investigation :• Bz distortion was about 25 G but Br distortion was negligible.• FEM calculation results agreed with hall probe & e-beam detection.
► Dynamic magnetic field error investigation :• Vertical displacement of KSTAR plasma found in 2008/ 2009. • Up-down asymmetric shape of the cryostat structure could generate
asymmetric eddy current (ITER will have the same issues).
EX/5-1
23rd IAEA Fusion Energy Conference, Daejeon Korea, 11-16 October 2010 14
► Bz deformation due to ferromagnetic incoloy effect is compensated in 2010 KSTAR start-up scenario.
1.3 1.4 1.5 1.6 1.7 1.8 1.9 2 2.1 2.2-70
-60
-50
-40
-30
-20
-10
0Radial Bz profile around current channel formation phase
R [m]
Bz
[G]
KSTAR shot #2068 in 2009KSTAR shot #3148 in 2010
Required Bz for Ip=8 kA
Required Bz for Ip=10 kA
Modified Bz slope prevents plasma inboard crashduring initial current channel formation phase.
Effect of Incoloy on Plasma Startup EXS/P2-12
23rd IAEA Fusion Energy Conference, Daejeon Korea, 11-16 October 2010 15
Robust Discharges up to 500 kA
PF coil current waveforms for 500 kA discharge
First 500 kA discharge without tuning the plasma control precisely (red) compared to the controlled discharges (blue)
23rd IAEA Fusion Energy Conference, Daejeon Korea, 11-16 October 2010 16
Perspective Toward Steady-State Operation
SC magnet system for steady-state :• Reliable operations of SC magnet & cryogenic facility for long pulse operation
• Magnetic material effects on magnetic configuration characterized
Divertor & PFC :• Active-cooling on PFC & divertor will be prepared for long pulse operation• Particle and flow control (fueling, wall conditioning, pumping)• Dust characterization as a ITER safety issue
Heating & Current drive optimization :• Simulation study with ASTRA, ONETWO, TSC/TRANSP predicts possible steady-state operation scenarios
• Long-pulse, non-inductive NBCD, LHCD, ECCD being installed
Advanced confinement by active plasma control:• Predictive simulations showed the possibilities of control of ELM, RWMand NTM by active means
• Extensive experimental program will be done for advanced confinementphysics using profile diagnostics, heating and current drive systems andIVCC
Overview of
KSTARInitial Experiments
II. KSTAR AS A STEADY-STATE DEVICE
• Super-conducting Magnets
•Heating & Current Drive• Active Plasma Control• Plasma-Wall Interaction
23rd IAEA Fusion Energy Conference, Daejeon Korea, 11-16 October 2010 18
KSTAR Specification Role in 2010
NBI
14 MW, 300 s D0/H0- Two beam lines- Three ion sources per each
beam line- Positive based ion source at120 keV
-Ion heating & CD-H-mode in initial phase
1 MW D0- One beam lines- One ion source- Beam energy : max. 80 keV- Beam pulse : less than 2 s
ICRF30 – 60 MHz, 8 MW(source), 300 s-Sources: Four 2MW transmitter
-Ion & electron heating in high density-On- and off-axis CD-Wall cleaning by RF discharge between shot
Frequency : 30 MHzSource power : < 1 MWPulse : <5 sUse 2 straps in the antenna
LHCD 5 GHz, 2 MW(source), 300 s- 4 x 500 kW CW klystrons
-Electron heating-Off-axis CD for plasma current profile control-RS-mode
ECH/CD
84/110 GHz, 0.5 MW(source), 2 s-84 GHz, 0.5 MW gyrotron
170 GHz, 3 MW(source), 300 s- 3 x 1 MW CW gyrotrons
• 84 (or 110) GHz ECH Startup system-Assisted startup using pre-ionization
•170 GHz ECCD system-2nd harmonic heating & CD-NTM stabilization leading to high beta-Sawteeth mode control (heating around q=1 surface)
ECH-assisted start up with
110 (and 84) GHz, 0.5 MW (5 s)Gyrotron
KSTAR Heating and Current Drive Systems
23rd IAEA Fusion Energy Conference, Daejeon Korea, 11-16 October 2010
►Successful pre-ionization with 2nd harmonic ECH• 2nd harmonic ECH pre-ionization : 1.5 T with 84 GHz and 2.0 T at 110 GHz• Low voltage for startup could be lowered to 2 V.• Pre-ionization scanned according to injection direction, gas pressure and
ECH power. Power threshold was about 250 kW. • 2nd harmonic ECH pre-ionization could be applicable to ITER startup.
19
#1949TF = 20.36 kA
R = 1.8 m
t=-6.8 ms
Black: 84 GHz in 2008 (#794)Blue: 110 GHz in 2009 (#1767)
Plasma current
ECH (not calibrated)
Electron density (line-integrated)
Neutral pressure
Loop voltage Dα
t=0 t=0
ECH pre-ionization for 84 GHz and 110 GHzECH-assisted startup
ECH-assisted Startup EXW/P2-05
23rd IAEA Fusion Energy Conference, Daejeon Korea, 11-16 October 2010
► Time delay in 2nd harmonic ECH and low electron density of pre-ionization are potentially harmful for machine safety.
► Before the formation of current channel (i.e. good confinement), low electron density of pre-ionization state cannot effectively absorb ECH beam power.
20
ECH-assisted Startup
a) ECH power (kW)
b) Electron line density
c) Da emission (A.U.)
2.3x10-18 m-2
300 kW
90 ms delay
0.8x10-18 m-2
t=0 (PF blip timing)
KSTAR shot 3124
20
Arc by reflected ECH beam around t=-43 msArc by reflected ECH beam around t=-43 ms
23rd IAEA Fusion Energy Conference, Daejeon Korea, 11-16 October 2010
► To prevent the damage due to ECH beam, KSTAR adopts Ohmic breakdown -ECH-assisted burn-through scenario.
► Background plasma produced by Ohmic breakdown of neutrals can effectively absorb ECH power without the reflection of ECH beam.
21
ECH-assisted Startup
21
d) ECH power (kW)
b) Electron line density
c) Da emission (A.U.)
a) Plasma current (A)
5.0x10-18 m-2
t=0 (PF blip timing)
250 kW
50 ms delay
KSTAR shot 3223
Current channel formation from background plasma
Current channel formation from background plasma
23rd IAEA Fusion Energy Conference, Daejeon Korea, 11-16 October 2010 22
Beam-Line in the Main Experimental Hall
Ion Source Power Supplies
Fabrication and Installation of the 1st NBI (NBI-1)
23rd IAEA Fusion Energy Conference, Daejeon Korea, 11-16 October 2010 23
Deuterium Beam Extraction
▶The achieved beam data and the waveforms of the 3-s beam extraction with the beam energy of 80 keV and the beam current of 27 A
FTP/P6-16
23rd IAEA Fusion Energy Conference, Daejeon Korea, 11-16 October 2010 24
Divergence and Perveance Doppler Shifted Spectrum
Beam Divergence and Species Ratio
q D+ : D2+ : D3
+ = 74 % : 23 % : 3 %
(at 64 kV/19 A, 3 s, 1.13 μperv)
23rd IAEA Fusion Energy Conference, Daejeon Korea, 11-16 October 2010 25
First Beam Injection
2.8 2.85 2.9 2.95 3 3.05 3.1 3.15 3.20
0.5
t [s]NB
pow
er
[MW
]
2.8 2.85 2.9 2.95 3 3.05 3.1 3.15 3.21.82
2.2
t [s]
Da [A
.U.]
2.8 2.85 2.9 2.95 3 3.05 3.1 3.15 3.20
500
t [s]
FC
count [#
]
1st NB test shot : 0.4 MW with 50 keV for 50 msec Shot No. : 3455
A test shot to find beam trajectory without PF blip and
ECH pre-ionization
A test shot to find beam trajectory without PF blip and
ECH pre-ionization
Beam Power
Neutron (Fission chamber)
Da
23rd IAEA Fusion Energy Conference, Daejeon Korea, 11-16 October 2010
▶ Transmitter• Frequency: 30, 37, 45, 50, 60MHz• Anode V/I: 22.2 kV/ 122 A• Screen grid V/I: 980 V/ 2.4 A• Control grid V/I: -470 V/ 9.2 A• Input RF power: 86.2 kW• Efficiency of FPA: 64.7%• VSWR (Driver/FPA): 1.22• VSWR (FPA/Dummy load): 1.51• Ion pump current: 0.6 mA
2 MW ICRF System
26
IC Wall Cleaning Experiments In 2009
EXW/P7-11
ICRH Experiment Result In 2009 Campaign
23rd IAEA Fusion Energy Conference, Daejeon Korea, 11-16 October 2010
Bay Em
polarizer
Power monitor
Gauge
Pump-out Tee
D1
Torus Hall
ECH
WG SW
38 m
14 m
6 m
Arc detector
Arc detector
Power monitor
170 GHz, 1 MW ECH/CD system (2011)
1 MW, CW, 170 GHz Gyrotron
Goals: → H-mode: requires ECH for NTM control→ Steady-state: definitely requires off-axis CD ® ECCD + LHCD
2011
2013
2015
Transmission Line§ Total length ~ 70 m§ 63.5 mm corrugated circular waveguide§ 8 Miter bends§ No diamond window§ Estimated transmission loss 20%
Dummy load
JAEA
Launcher (PPPL)
27
Output RF
23rd IAEA Fusion Energy Conference, Daejeon Korea, 11-16 October 2010
5 GHz, 0.5 MW LHCD system (2011)► CW prototype Klystron ► LH launcher system
• The prototype of 5 GHz, 500 kW CW klystron for KSTAR, has been commissioned and tested using two dummy loads successfully.
• The 5 GHz, 1 MW un-cooled LH launcher for KSTAR LHCD is designed.• For the RF performance test of the LH launcher, a prototype of one-channel 4-way
splitter is under fabrication.
Component Spec. 2010 2011 2012 2013
Klystron 5 GHz, 500 kW, CW Commissioning Order (for 1 MW) Installation
Launcher Based on 4-waysplitter
DesignPrototype fabrication
Fabrication (for 1 MW, 2 s)
Transmission Line WR 187 w/g, 70 m, 760 torr SF6 gas
DesignOrder
Installation
Power Supply 2 MW thyristor typeInstallation (for 500 kW)
CommissioningChange to chopper type
Order (for 1 MW)Fabrication
Installation
Control system EPICS and PLC based remote control
InstallationCommissioning
28
► Future work
23rd IAEA Fusion Energy Conference, Daejeon Korea, 11-16 October 2010
2008 2009 2010 2011 2012
ECH/CD
- 84 GHz 0.5 MW/0.4 s 0.5 MW/2 s 0.5 MW/2 s 0.5 MW/2 s 0.5 MW/2 s
- 110 GHz 0.5 MW/2 s 0.5 MW/2 s 0.5 MW/2 s
- 170 GHz 1 MW/10 s 1 MW/300 s
LHCD 0.5 MW/2 s 1 MW/2 s
ICRF 30MHz50kW/10s
45 MHz300 kW/10 s 1 MW/10 s 1 MW/10 s 2 MW/300 s
NBI 80 keV D01.0 MW/2 s
100 keV D02.5 MW/10 s
120 keV D05 MW/300 s
Total 0.5 MW < 1 MW 2 MW > 5 MW > 9 MW
29
H&CD System Upgrade
23rd IAEA Fusion Energy Conference, Daejeon Korea, 11-16 October 2010 30
Predictive Simulation
0.0 0.2 0.4 0.6 0.8 1.00.0
0.5
1.0
1.5
2.0
jLH
jTOT
jNBjBS
Curre
nt D
ensi
ty (M
A/m
2 )
rtor
0 2 4 6 8 10 120.0
0.2
0.4
0.6
0.8
LHCD
NBCD
total NI
bootstrap
total
Ip, M
ATime, s
Predictive simulations have been performed to establish steady-state operations by optimising current drive schemes in KSTAR.
TSC/TRANSP (PPPL)
ONETWO (ORNL)
ASTRA (SNU/NFRI)
ITER-relevant steady state scenario• 0.8 MA, 1.95 T• fully non-inductive current drive with
a bootstrap current fraction above 0.6• βN above 3, H98(y,2) above 1.5
THS/P2-04
23rd IAEA Fusion Energy Conference, Daejeon Korea, 11-16 October 2010 31
Perspective Toward Steady-State Operations
SC magnet system for steady-state :• Reliable operations of SC magnet & cryogenic facility for long pulse operation
• Magnetic material effects on magnetic configuration characterized
Divertor & PFC :• Active-cooling on PFC & divertor will be prepared for long pulse operation• Particle and flow control (fueling, wall conditioning, pumping)• Dust characterization as a ITER safety issue
Heating & Current drive optimization :• Simulation study with ASTRA, ONETWO, TSC/TRANSP predicts possible steady-state operation scenarios
• Long-pulse, non-inductive NBCD, LHCD, ECCD being installed
Advanced confinement by active plasma control:• Predictive simulations showed the possibilities of control of ELM, RWMand NTM by active means
• Extensive experimental program will be done for advanced confinementphysics using profile diagnostics, heating and current drive systems andIVCC
Overview of
KSTARInitial Experiments
II. KSTAR AS A STEADY-STATE DEVICE
• Super-conducting Magnets• Heating & Current Drive
•Active Plasma Control• Plasma-Wall Interaction
23rd IAEA Fusion Energy Conference, Daejeon Korea, 11-16 October 2010 33
Parameters Descriptions
Coil radiusTop & Bottom IVCC : 2,120 mmUpper & Lower IVCC : 2,500 mm
Coil case 3 mm thickness of SS316LN
ConductorHalf hard copper32 mm × 15 mm with 7 mm dia. Hole
Turn insulation 1 mm thickness of Kapton/glass fiber/ epoxy
Section insulation 1 mm thickness of Glass fiber/ epoxy
Ground insulation 1 mm thickness of Glass fiber/ epoxy
Total cross-section 80 mm × 80 mm
Coil Case
Filler
Ground Insulation
Section Insulation
Turn InsulationConductor
Corner Roving Filler
Top IVCC
Upper IVCC
Lower IVCC
Bottom IVCC
In-Vessel Control Coil (IVCC) FTP/P6-09
23rd IAEA Fusion Energy Conference, Daejeon Korea, 11-16 October 2010 34
Upper VerticalControl Coil
Upper Radial Control Coil
Top FEC/RWM
Middle FEC/RWM
Bottom FEC/RWM
Lower RadialControl Coil
Schematic Diagram
Lower VerticalControl Coil
Upper IVC
Top FEC/RWM
Upper IRC
Middle FEC/RWM
Lower IVC Lower IRC
Bottom FEC/RWM
Electrical Connection Scheme of IVCC
23rd IAEA Fusion Energy Conference, Daejeon Korea, 11-16 October 2010 35
Upper IVCCUpper IVCC
Top IVCCTop IVCC
Lower IVCCLower IVCC
Bottom IVCC
Bottom IVCC
Inboard Limiter(w/o tiles)
Inboard Limiter(w/o tiles)
Inboard Divertor(w/o tiles)
Inboard Divertor(w/o tiles)
Central Divertor(w/o tiles)
Central Divertor(w/o tiles) In-Vessel
CryopumpIn-Vessel
Cryopump
Coolant Manifold for PFCs
Coolant Manifold for PFCs
IVCC under Installation
23rd IAEA Fusion Energy Conference, Daejeon Korea, 11-16 October 2010 36
First Results of the IVCC
Vertical Stabilization By IVC
KSTAR #3408 @4.422
23rd IAEA Fusion Energy Conference, Daejeon Korea, 11-16 October 2010 37
Plasma Shaping THS/P2-05
23rd IAEA Fusion Energy Conference, Daejeon Korea, 11-16 October 2010 38
Passive Stabilizer
• Two toroidal- ring shaped plates, 9 mechanical bridges • Segmented into quadrants, each quadrant is connected to
each other through gap resistors (totally 1.2 mW in toroidal)• Total 32 sectors (16 x 2)• 12 vertical supports, 4 horizontal supports • Upper parts support lower parts with 9 mechanical bridges • Graphite tile (impurity < 10ppm)• Back plate : CuCrZr alloy, water cooled
Changing material
Increasing cuts
THS/P2-05
23rd IAEA Fusion Energy Conference, Daejeon Korea, 11-16 October 2010
►X-ray Imaging Crystal Spectrometer· Ti & Te & toroidal rotation profile
39
Wavelength
Spatial information Det 1
Det 4
Det 3
Det 2
w z
3.9494 Å 3.9944 Å
►Charge Exchange Spectroscopy· Ti & toroidal rotation profiles · 17 ch (act 8ch & back. 8 ch)
► ECE radiometry· Frequency : 110 ~ 196 GHz· Sawtooth measurement from 2009
Plasma
HFS LFS
~10cm~15cm
30~90cm
►ECE Imaging· Simultaneous high & low field sides
· 384 ch (24 x 16) · operation at 2 T
Plasma Profile Measurements
►Thomson scattering· Channels : core 4 & edge 5 (design : 42 channels)· Nd : Yag Laser : 2J, 10 Hz (ITER Laser 5J, 100Hz in 2011)
EXS/10-1
23rd IAEA Fusion Energy Conference, Daejeon Korea, 11-16 October 2010
Zoom lenses
Dual Antenna/Mixer
Arrays
Local Oscillators (BWO)
HFS LFS
Focus lenses
Cassette
► Commissioned on Oct. 8, 2010► Target Sawtooth: OH discharge w/ ~1% fluctuation► More information in Oral talk, EXC/10-1Ra (Park, H.)
Before crashm=1 mode
After crashFlattened Te
First KSTAR ECEI data
40
KSTAR ECE Imaging (ECEI) System Commissioning
40
23rd IAEA Fusion Energy Conference, Daejeon Korea, 11-16 October 2010
Detector Head (AXUV16ELG)
Be filter : 50 um thickness
1.8 1.9 2 2.1 2.2 2.3 2.4 2.5 2.60.215
0.22
0.225
0.23
0.235
0.24
0.245
0.25
1.8 1.9 2 2.1 2.2 2.3 2.4 2.5 2.60.22
0.225
0.23
0.235
0.24
0.245
0.25
0.255
SXR37(V)
SXR40(V)
Time (s)
Ch 37: outside inversion radius
Ch 40: inside inversion radius
à Sawtooth inversion radius: 19 cm
1 1.2 1.4 1.6 1.8 2 2.2 2.4 2.6 2.8
100
200
300
400
500
600
700
800
900
1000
Time (s)
Freq
uenc
y (H
z)
-20
-18
-16
-14
-12
-10
-8
-6
-4
25 Hz of sawtoothoscillation
Oscillation frequency: 25Hz
Sawtooth inversion radius : ~19 cm
ch 37
ch 40
Installed SXR array
First result of SXR
41
23rd IAEA Fusion Energy Conference, Daejeon Korea, 11-16 October 2010 42
▶Peak bN exceeds 0.6, peak stored energy exceeds 50 kJ, Ip reaches 335 kA▶Reconstruction includes evolution of vessel currents
(a)
2048
Plasma reconstructions of long pulse, high current plasmas
THS/P2-05
23rd IAEA Fusion Energy Conference, Daejeon Korea, 11-16 October 2010 43
Ideal MHD Stability Analysis for KSTAR Target AT Mode
L-mode edge profile H-mode edge profile
▶ A detailed calculation with DCON, GATO for equilibrium including H-mode edge profile
▶ KSTAR target AT mode with βN > 5 possible with optimized profiles of p(r), q(r)
23rd IAEA Fusion Energy Conference, Daejeon Korea, 11-16 October 2010 44
Perspective Toward Steady-State Operations
SC magnet system for steady-state :• Reliable operations of SC magnet & cryogenic facility for long pulse operation
• Magnetic material effects on magnetic configuration characterized
Divertor & PFC :• Active-cooling on PFC & divertor will be prepared for long pulse operation• Particle and flow control (fueling, wall conditioning, pumping)• Dust characterization as a ITER safety issue
Heating & Current drive optimization :• Simulation study with ASTRA, ONETWO, TSC/TRANSP predicts possible steady-state operation scenarios
• Long-pulse, non-inductive NBCD, LHCD, ECCD being installed
Advanced confinement by active plasma control:• Predictive simulations showed the possibilities of control of ELM, RWMand NTM by active means
• Extensive experimental program will be done for advanced confinementphysics using profile diagnostics, heating and current drive systems andIVCC
Overview of
KSTARInitial Experiments
II. KSTAR AS A STEADY-STATE DEVICE
• Super-conducting Magnets• Heating & Current Drive• Active Plasma Control
•Plasma-Wall Interaction
23rd IAEA Fusion Energy Conference, Daejeon Korea, 11-16 October 2010 46
11
22
22
33
55
44
66
77
88
Inboard Limiter22 Divertor (DN, 20 s)33 Passive Stabilizer44 Poloidal Limiter
11 In-Vessel Control Coil66 NB Armor77 In-Vessel Cryo-pump88 Mechanical Brides for the Passive Stabilizer
55
In-Vessel Components
23rd IAEA Fusion Energy Conference, Daejeon Korea, 11-16 October 2010
Wall conditioning
2009 2010
•Baking •Vacuum vessel at 130 oC (hot water)•PFC at 130 oC (conduction)
•Vacuum vessel at 130 oC•PFC at 200 oC (Hot N2 gas)
•Glow discharge
•GDC (H2 & He)•During cool-down, GDC at daytime•During experiments, GDC at night
• Optimum GDC duration was about 2 hrseach
• Outgassing rate recover after about 5 hrs
•GDC (H2 & He)•During cool-down, GDC at daytime
•During experiments, GDC in the morning if required
• ICWC
• ICWC (He)• ICWC between shot or lunch time
• ICWC study according to pressure & power scan
• H & D Isotope exchange was observed.
• ICWC (He)• ICWC in the morning or lunch time
•Boronization
•Carborane injected (50 g)
• Impurity in vacuum decreased and maintained for about 100 shots
• In-homogeneus deposition
•Carborane
• Injection at 4 place for the homogeneus coating
Wall Conditioning Process
47
EXD/P3-17
23rd IAEA Fusion Energy Conference, Daejeon Korea, 11-16 October 2010
Campaign PFC surface( unit : ㎡) Baking system
1st 1.54 • Water baking system for VV ( 100 ℃)
2nd 11• Water baking system for VV ( 130 ℃)• Jacket heater baking system for duct ( 120 ℃)
3rd 54
• Water baking system for VV ( 130 ℃)• Jacket heater baking system for duct ( 120 ℃)• Hot gas baking system for PFCs ( 200 ℃)
KSTAR 1st Campaign
KSTAR 2nd Campaign
KSTAR 3rd Campaign
Effect of Baking
Total outgassing
2nd
Campaign3rd
Campaign
Total ( mbar·ℓ/s ) 2.13 ×10-4 6.49 ×10-4
Per unit area
( mbar·ℓ/s∙㎡)1.93 ×10-5 1.22 ×10-5
48
23rd IAEA Fusion Energy Conference, Daejeon Korea, 11-16 October 2010
Vacuum Wall Condition
► During the baking, D2 and He GDC is performed in both campaigns.
► The water and oxygen levels in the vacuum vessel in the 3rd campaignare much lower than that after the 1st boronization in the 2nd campaign.
49
23rd IAEA Fusion Energy Conference, Daejeon Korea, 11-16 October 2010 50
▶Inter-shot ICWC effectively removes H2O and suppresses the water level in the vacuum vessel.
▶With an overnight D2 GDC, the walls were saturated by ~1024 D atoms (similar to TS).
▶H retention rate of 1.2-3.8ⅹ1020
H/sec is measured with almost no sign of saturation in bulk.
▶H(D) removal rate of 0.17-6.11ⅹ1019 H(D)/sec.
▶Other impurity removal rate ~ 1016
-1017 molecules/sec.
Effects of ICWC and Particle Balance
23rd IAEA Fusion Energy Conference, Daejeon Korea, 11-16 October 2010
Surface after Plasma-Dust Interaction
Lab
KSTAR
▶ Different surface/internal micro-structures are identified.▶ This is due to the crystallization and the plasma-dust interaction.▶ Micro-crystal structures have a size of about 1-2 um.▶ Micro-structures are broken into pieces which leads to smaller metal dusts.
Dust Researches in KSTAR
Surface Morphology
51
FTP/P1-32
23rd IAEA Fusion Energy Conference, Daejeon Korea, 11-16 October 2010 52
-0.05 0.00 0.05 0.100
1
2
3
4
5
6
7
8
9
Hea
t flu
x on
div
erto
r (M
W/m
2 )
Distance from striking point (m)
12 MW 10 MW 8 MW 6 MW 4 MW
2 4 6 8 10 12 140123456789
10
q peak
on
dive
rtor (
MW
/m2 )
Input power (MW)
gsput=0.0 % gsput=0.1 % gsput=1.0 % gsput=3.0 %
▶Using B2 code, divertor heat fluxes calculated for various operation powers and C+ impurity condition for KSTAR divertor model
▶It is shown that C+ impurity changes the intensive radiation position from outer SOL near divertor to private region near X-point, reducing peak heat flux
Divertor Transport Simulation for KSTAR
23rd IAEA Fusion Energy Conference, Daejeon Korea, 11-16 October 2010 53
Perspective Toward Steady-State Operations
SC magnet system for steady-state :• Reliable operations of SC magnet & cryogenic facility for long pulse operation
• Magnetic material effects on magnetic configuration characterized
Divertor & PFC :• Active-cooling on PFC & divertor will be prepared for long pulse operation• Particle and flow control (fueling, wall conditioning, pumping)• Dust characterization as a ITER safety issue
Heating & Current drive optimization :• Simulation study with ASTRA, ONETWO, TSC/TRANSP predicts possible steady-state operation scenarios
• Long-pulse, non-inductive NBCD, LHCD, ECCD being installed
Advanced confinement by active plasma control:• Predictive simulations showed the possibilities of control of ELM, RWMand NTM by active means
• Extensive experimental program will be done for advanced confinementphysics using profile diagnostics, heating and current drive systems andIVCC
Overview of
KSTARInitial Experiments
III. COLLABORATION
23rd IAEA Fusion Energy Conference, Daejeon Korea, 11-16 October 2010
World Leading Experts(International)
55
Collaboration frame of KSTAR
World Class Institute (WCI) Program
WLEWCITh/Sim.
Diagnostic & SSO
(POSTECH)
Reactor Engineering
(SNU)
Plasma Heating(KAERI)
Edge Plasma(HYU)
Plasma Transport
(KAIST)
ITER Pilot R&DITER-IO Fusion
SimulationSciDAC (US), etc.
KSTAR Co-Exp.ITER Members
Non-ITER
International Collaboration
Matching Funds& Collaboration
WLE
WLE
WCIExp2
WCIExp1
Domestic Collaboration
Fusion R&D Collaboration
23rd IAEA Fusion Energy Conference, Daejeon Korea, 11-16 October 2010 56
Physics issues in KSTAR boring plasma Nature of transport• characterization of non-local transport feature, like intermittent or avalanche• mechanism of cold-pulse propagation (edge cooling -> core heating)• new approach for transport analysis (analysis of local and non-local processes)
Edge transport (for pre-LH transition phase)• thorough measurement & analysis of edge turbulence characteristics• primary mechanism among various candidates, like ITG, RBM, DTE, ETG etc.• clarification of multi-component shearing (ZF, GAM) and dynamics (burst, pulsation)
Electron thermal transport• origin of LOC/neo-Alcator scaling (the model of DTEM is not sufficient?)• Te profile stiffness degree -> exponent and coefficient• nonlinear heat pinch
Particle/impurity transport• mechanism of improved particle confinement (IOC, RI/Z-mode, p-ITB etc.)• density profile stiffness degree• dominant particle pinch mechanism?• turbulent impurity transport
Momentum transport• dependences of intrinsic rotation on density, shape, SOL-flow etc. in Ohmic, L-mode • correlation of LOC->SOC with toroidal rotation direction change
23rd IAEA Fusion Energy Conference, Daejeon Korea, 11-16 October 2010 57
Joint Experiments in 2010
• Vertical stability controls• Real-time EFIT & isoflux control
• MHD (ECEI, SXR, MC)• Fast filtered imaging diagnostic : TV
• ECH pre-ionization (fundamental) • ICRF heating : coupling / D / minority / fastwave• NB heating
• ECH discharge cleaning• hydrocarbon flux/energy by deposition probe
• Sawtooth• Runaway• TAE• Locked mode & tearing mode• Operation space : density limit
• L-H transition• Rotation properties• Radial transport of impurity• Low density Ohmic confinement
►55 proposals submitted
►Classified into 6 tasks• Plasma commissioning (7)• Diagnostics (9)• Heating and current drive (10)• Plasma wall interaction (7)• MHD (15)• Transport and confinement (7)
Domestic (41)
§ NFRI (22) § POSTECH (6)§ KAERI (11)§ SNU (2)
International (14)
§ GA (6)§ PPPL (2) § ORNL (1)§ Far-Tech (1)§ ANU (2)§ JAEA (2)
23rd IAEA Fusion Energy Conference, Daejeon Korea, 11-16 October 2010
§ TC-2 Power ratio – Hysteresis and access to H-mode with H~1§ TC-3 Scaling of the Low-Density Limit of the H-mode threshold§ TC-9 Scaling of intrinsic plasma rotation with no external momentum input§ TC-14 RF rotation drive§ PEP-22 Controllability of pedestal and ELM characteristics by edge ECH/ECCD/LHCD§ PEP-28 Physics of H-mode access with different X-point height§ DSOL-8 ICRF conditioning§ DSOL-9 C injection experiments to understand C migration§ DSOL-13 Deuterium co-deposition with carbon in gaps of plasma facing components§ MDC-13 Vertical stability physics and performance limits in Tokamaks with highly elongated plasmas§ MDC-15 Disruption database development§ MDC-16 Runaway electron generation, confinement, and loss § IOS-2.1 ECRH breakdown assist at 20-degree toroidal angle§ IOS-2.2 Ramp-down from q95=3§ IOS-5.2 Maintaining ICRH coupling in expected ITER Regime.§ IOS-6.2 li controller (Ip ramp) with primary voltage / additional heating§ DIAG-3 Resolving the discrepancy between ECE and TS at high Te§ DIAG-4 Field test of a Capacitance diaphragm Gauge as a dust monitor for ITER
58
ITER High Priority Research Topics (IEA/ITPA)
Keywords of key issues :Shaping / H-mode / rotation / disruption ECRH breakdown / ICRF conditioning / runaway / dust
Overview of
KSTARInitial Experiments
IV. FUTURE PLAN
23rd IAEA Fusion Energy Conference, Daejeon Korea, 11-16 October 2010
5-Year Operation Plan (Phase I)2012
‘12. 3 ~‘12. 8
• Profile control• ITER shape• ELM & disruption
• BT : 2 ~ 3.5 T• IP > 1 MA • tP ~ 20 s• Ti ~ 5 keV• Shape ~ DN & SN• Gas : D2
• TF : 35 kA [3.5 T] • PF : +/-20 kA (~8Wb)• IVCC : FEC,RMP,RWM• Grid: 100 MVA
+ Cryopump operation
• ECH(84/110G):0.5MW• ECCD(170G): 1MW• ICRH : 1.5MW • NBI : 5MW• LHCD : 0.3MW
+ MSE / MIR / BES / VUV / CX-NPA /etc
2011
‘11. 4 ~‘11. 9
• H-mode • MHD • Disruption• Wall interaction
• BT : 2 ~ 3.5 T• IP > 1 MA• tP > 10 s• Ti ~ 3 keV• Shape ~ DN & SN• Gas : D2
• TF : 35 kA [3.5 T] • PF : +/-15 kA (~6Wb)• IVCC : VS• Grid: 100 MVA
+ PFC cooling
• ECH(84/110G):0.5MW• ECCD(170G): 1MW• ICRH : 1.5MW • NBI: 2MW• LHCD: 0.3MW
+ FIR / Div. bolometer /X-ray pinhole / Coherence imaging/ fast-ion / etc
2010
‘10.6 ~‘10. 12
• Shape control• L-mode • MHD study• Wall conditioning
• BT : 2 ~ 3.5 T• IP > 0.5 MA• tP > 5 s• Ti ~ 1 keV• Shape ~ DN (κ2.0)• Gas : D2
• TF : 35 kA [3.5 T] • PF : +/-10 kA (~4 Wb)• IVCC : VS• Grid: 100 MVA
+ Divertor+ Passive stabilizer + In-vessel coil + PFC baking
• ECH(110G):0.5MW• ICRH: 1MW • NBI: 1MW
+ Thomson (5ch)/ ECEI / IRTV / Image Bolometer / CES / neutron / XICS-2 / Ellipsometry /
2009
‘09. 8 ~‘09.12
• Startup stabilization• ECH pre-ionization• ICRF wall
conditioning
• BT : 2 ~ 3.5 T• IP > 0.3 MA• tP > 2 s• Te ~ 1 keV• Shape ~ Circular• Gas : D2
• TF : 35 kA [3.5 T] • PF : +/-4 kA (~2 Wb)• Grid : 50 MVA
• Inboard limiter + Boronization+ ICRF DC
• ECH(110G):0.2MW, 2s• ICRH: 0.3MW, 1s
+ XICS / Soft X-ray / Hard X-ray/ Resistive Bolometer / Probe / Reflectometer
• e-beam
2008
‘08. 3 ~‘08. 8
• First plasma startup• 2nd Harmonic ECH
pre-ionization
• BT ~ 1.5 T• IP > 0.1 MA• tP > 0.1 s• Te ~ 0.3 keV• Shape ~ Circular• Gas : H2
• TF : 15 kA [1.5T)• PF : 4 kA (~1 Wb)• Grid : 50 MVA
• Inboard limiter (belt)• Gas puff• Glow DC
• ECH(84G):0.3MW, 0.4s
• Magnetic Diagnostics / MMWI / ECE / Ha / VS / filterscope / TV /
• Hall probe array
Campaign
Operation Time
Experimental goals
Operation Parameters
Magnetic Control
Vacuum Conditioning
Heating & Current Drive
Diagnostics
60
23rd IAEA Fusion Energy Conference, Daejeon Korea, 11-16 October 2010
Operation Phase I2008 ~ 2012
• Superconducting tokamak operation
• First plasma & inductive current ramp (2 MA)
• Plasma shaping&heating(DN & SN, H-mode)
SC Tokamak operation
Operation Phase II2013 ~ 2017
• Steady-state operation & ITER pilot device roles (300 s+)
• Plasma heating & non-inductive current drive
• Instability control in H-mode and AT-mode
Long-pulse operation
Operation Phase III2018 ~ 2022
• Advanced scenario for DEMO beyond ITER
• High-beta and high bootstrap current scenario
• Extreme operation of the superconducting tokamak
High performance operation
Phase IV2023 ~
• DEMO Engineering
• DEMO simulator
• Reactor material test
DEMO test bed
KSTAR will be operated as an international collaboratory to exploit the key scientific and technological issues for the ITER and attractive fusion reactor.
61
Long-term Operation Plan
► Divertor plasma (‘10)
► H-mode operation (‘11)
► Fast stabilization (‘12)
Second Campaign (‘09)
320kA3.6sec3.0Tesla
First Plasma (‘08)
133kA0.25sec1.5Tesla
Overview of
KSTARInitial Experiments
V. SUMMARY
23rd IAEA Fusion Energy Conference, Daejeon Korea, 11-16 October 2010 63
Perspective Toward Steady-State Operations
SC magnet system for steady-state :• Reliable operations of SC magnet & cryogenic facility for long pulse operation
• Magnetic material effects on magnetic configuration characterized
Divertor & PFC :• Active-cooling on PFC & divertor will be prepared for long pulse operation• Particle and flow control (fueling, wall conditioning, pumping)• Dust characterization as a ITER safety issue
Heating & Current drive optimization :• Simulation study with ASTRA, ONETWO, TSC/TRANSP predicts possible steady-state operation scenarios
• Long-pulse, non-inductive NBCD, LHCD, ECCD being installed
Advanced confinement by active plasma control:• Predictive simulations showed the possibilities of control of ELM, RWMand NTM by active means
• Extensive experimental program will be done for advanced confinementphysics using profile diagnostics, heating and current drive systems andIVCC
23rd IAEA Fusion Energy Conference, Daejeon Korea, 11-16 October 2010 64
SUMMARY
§Successful initial operation of KSTAR showed the capability of advanced and steady-state operation which are essential for ITER and future fusion reactors.
§ECH-assisted and Ohmic plasma discharges up to 500 kA for 7 seconds have been routinely achieved.
§Plasma shaping and heating studies with active control tools are being performed and H-mode will be tried out in 2010 campaign.
§Fifty-five joint plasma experiments with domestic and international collaborators are being conducted to achieve the targeted goals in 2010 campaign, which consists of the essential part of KSTAR research activities.
23rd IAEA Fusion Energy Conference, Daejeon Korea, 11-16 October 2010 65
Presentations on KSTAR in FEC2010Presentation Author Title
FTP/P1-32 SH Hong On the spherical dusts in fusion devices
EXS/P2-09 SH Hahn Approaches on vertical stability and shape control in KSTAR
EXS/P2-12 J Kim Stable plasma startup in KSTAR under various discharge conditions
EXW/P2-05 M Joung ECH-assisted startup by the second harmonic EC waves in KSTAR
EXW/P2-09 C Ryu Observation and analysis of HF MHD activities during sawteeth in KSTAR
THS/P2-04 YS Na Real-time control of NTM in time-dependent simulation on KSTAR
THS/P2-05 YS Park KSTAR equilibrium operating space and projected stabilization at high beta
THW/P2-04 J Seol Modeling of ECH-assisted startup in a tokamak
EXD/P3-17 WC Kim Initial phase wall conditioning in KSTAR
THC/P3-03 KM Kim Effects of pellet ELM pacing on mitigation of ELM energy loss in KSTAR
THC/3,4 SS Kim, JM Kwon ITB & momentum transport simulation
EXS/P5-08 YM Jeon Equil. Reconstruction of KSTAR plasmas
EX/5-1 SW Yoon Effects of magnetic materials on in-vessel magnetic configuration in KSTAR
FTP/P6-05 HK Na Current operation status of KSTAR
FTP/P6-09 HL Yang Status and result of the KSTAR upgrade for 2010 campaign
FTP/P6-16 YS Bae Commissioning results of the KSTAR NBI system
FTP/P6-28 SH Park Thermo-hydraulic characteristics of KSTAR magnet system
EXW/P7-11 JG Kwak First results from ICRH experiments in KSTAR
EXS/10-1 H Park Comparative study of sawtooth physics and Alfven waves via 2D ECEI