1. 1J. Stober, EC17, Deurne, May 2012 ECRH on ASDEX Upgrade System Status, Feed-Back Control, Plasma Physics Results Max-Planck-Institut für Plasmaphysik J. Stober, A. Bock, M. Reich, F. Sommer, W. Treutterer, D. Wagner, L. Gianone, A. Herrmann, F. Leuterer, F. Monaco, M. Marascheck, A. Mlynek, S. Müller, M. Münich, E. Poli, M. Schubert, H. Schütz, H. Zohm and the ASDEX Upgrade Team Max-Planck-Institut für Plasmaphysik, EURATOM Association, Garching, Germany A. Meier, Th. Scherer, D. Strauß, A. Vaccaro, J. Flamm, M. Thumm Karlsruhe Institue of Technology, EURATOM Association, Karlsruhe, Germany H. Höhnle, W. Kasparek, U. Stroth Institut für Plasmaforschung, Universität Stuttgart, Stuttgart, Germany A. Litvak, G.G. Denisov, A.V. Chirkov Institute of Applied Physics, RAS, Nizhny Novgorod, Russia E.M. Tai, L.G. Popov, V.O. Nichiporenko, V.E. Myasnikov, E.A. Soluyanova, S.A. Malygin GYCOM Ltd, Nizhny Novgorod, Russia

2. 2J. Stober, EC17, Deurne, May 2012 Status: 4 MW in plasma (almost) reached plasma current plasma density ECRH Power 140 GHz ECE diode Sniffer probes Power in plasma New system: 2.4 MW @ 140 GHz (0.82 + 0.76 + 0.85) or 2.1 MW @ 105 GHz (0.76 + 0.56 + 0.75) Old system: 1.5 MW for 2 s @ 140 GHz

3. 3J. Stober, EC17, Deurne, May 2012 Status of the new System 3 x 2-frequency gyrotrons (10 s) Output power 2.7 MW @ 140 GHz (0.91 + 0.82 + 0.95) 2.3 MW @ 105 GHz (0.84 + 0.62 + 0.84) Last gyrotron expected July 2012 (initially 2-f) X2, X3with all beamlines and frequencies O2reflectors only for beamlines 5 and 6 @ 140 GHz O1only @105GHz for Bt > 3T

4. 4J. Stober, EC17, Deurne, May 2012 Multi frequency project – window issues Gyrotron window - grooved-disk concept too fragile (A. Vaccaro, KIT) - final concept: separately mountable ring resonator Torus window - double disk window (FZK/KIT) successful low power tests in 2007 but failure at high power 2011 (600 kW, 4s) - ring resonator difficult on AUG due to space limitations If the resonator-window works, we consider the project a success. Further development of DD-window is considered a new project.

5. 5J. Stober, EC17, Deurne, May 2012 Ring Resonator Window (G. Denisov, IAP) Start w/o resonator mid 2012 Commission resonator early 2013 MOU

6. 6J. Stober, EC17, Deurne, May 2012 System Status: Topics addressed by other contributions FADIS and in-line ECE talks by W. Kasparek, W. Bongers, N. Doelman ECRH Stray-radiation poster by M. Schubert

7. 7J. Stober, EC17, Deurne, May 2012 Feed-Back Control ECRH/CD as actuator of discharge control system (DCS) : Power control under DCS: on/off tested; analogue prepared Mirror control under DCS: new system only, one axis only

8. 8J. Stober, EC17, Deurne, May 2012 New scheme: allows simultaneous central heating old scheme: central ECRH impossible new scheme: needs well focussed beam NTM stabilisation - Concept

9. 9J. Stober, EC17, Deurne, May 2012 NTM control – FB control scheme Real-Time Data Network  →  Torbeam Gyro- trons ECE  →   ECH,EQU  NTM,ECE  NTM P set  set  set T e,ch dB/dt  ECH 3/2 & 2/1 corre- lation z+()z+() z-()z-() r f ch MAX B,  mm rt- EQU nene DCN Mirror drives mode location  ECE (ch,z)  pol (r, z)  q_res,EQ U  ECH P n e - profile ne()ne() Data Acquisition Hardware MSX MHD controller MIR n=1 n=2 analogue from MIR d  /d 

10. 10J. Stober, EC17, Deurne, May 2012 NTM control – Launcher alignment Correlation ECE & linear comb. of Mirnov data corresponding to (n=2) or (2,1) Amplitude Phase mode location RT-TORBEAM (M. Reich et al., FST 2012)

11. 11J. Stober, EC17, Deurne, May 2012 NTM control – First feed-back attempts (28.4.2012) After ~ 100 ms minimum in n=2 amplitude lose robust localization / tracking rho (NTM) = rho (n=2) - 0.025 Wmhd beta_pol beta_N ICRH Amplitude n=1 n=2

12. 12J. Stober, EC17, Deurne, May 2012 Holographic Mirror with fast thermocouples to control beam position 1 st pass 2 nd pass top view O2 heating – Concept (PhD-Thesis H. Höhnle)

13. 13J. Stober, EC17, Deurne, May 2012 O2 heating – FB control scheme  (FF)  (FB) on – off (FF) interlock T max

14. 14J. Stober, EC17, Deurne, May 2012 Example : O2 heating with FB control TC for beam control and interlock P O2 [MW] n e [10 20 m -3 ] H-1 H-5 controller threshold (T TC,b -T TC,t ) K p [a.u.] Beam position after feedback control Beam position before feedback control TC for interlock poloidal launcher angle [mm] mirror FB – control corrects launching angle within 50 ms

15. 15J. Stober, EC17, Deurne, May 2012 Plasma physics results ECRH/ECCD is used in the majority of the AUG physics studies  review out of scope Recent studies using high EC power - L/H threshold at low density P. Sauter et al., NF 2012 - Rotation and toroidal momentum transport R. McDermott et al., PPCF 2011 - Advanced Tokamak scenarios MSE analysis in progress - Influence of heating mix on transport in H-mode (core/edge)

16. 16J. Stober, EC17, Deurne, May 2012 Comparison NBI - ECRH [- ICRH] (F. Sommer et al.) H-mode, q 95 = 4.0, f GW = 0.75 W mhd ~ 350 kJ, P rad ~ 1.5 MW, f ELM ~ 50 Hz, H 98 ~ 0.8, β N ~ 0.95, eff ~ 2 P total  3 MW 4 phases: -0 NBI 2.7 ECRH -0.8 NBI 2.0 ECRH -1.6 NBI 1.2 ECRH -2.4 NBI 0.6 ECRH

17. 17J. Stober, EC17, Deurne, May 2012 Influence of P ECRH on kinetic profiles (n e, T e,i, v tor ) With increase of ECRH frac. n e peaking increases T e less than 600 kW ECRH  20% T e increase T i 1/3 of ECRH power  15% decrease, effect saturates v rot_tor decreases (reduced torque input) only minor variations at the pedestal NBI fraction rises

18. 18J. Stober, EC17, Deurne, May 2012 Ion heat transport increases with ECRH fraction Increase of ion heat diffusivities as P ECRH increases - consistent with theoretical expectations for variation of T e /T i ECRH NBI 2.7 MW 2.0 MW 0.8 MW 1.2 MW 1.6 MW 0.6 MW 2.4 MW 3.0 MW #27242 F. Sommer et al., accepted by NF

19. 19J. Stober, EC17, Deurne, May 2012 Outlook ECRH-System - New ECRH system will be completed in 2012 (2f) - Long pulse 4f-gyrotron operation foreseen for early 2013 - Replacement of old system by 4 x 1MW/10s/2f in progress Feed-Back Control - Focus of FB control development in 2012 campaign on NTMs - Flexible RT-diagnostic layer easily adapted to new tasks Plasma Physics Studies - Characterize dominantly EC heated H-modes at lower nu* - many others

20. 20J. Stober, EC17, Deurne, May 2012

21. 21J. Stober, EC17, Deurne, May 2012 Future of multi-frequency project a)close project - realisation of long-pulse mf-gyrotron would be big success. - In principle also suitable for torus, but not in AUG set-up. b) continue - find reason for failure of DD-window (full wave simulation) - modify DD-Window if necessary. - build torus-window test-stand in Garching - start with high power short pulse, measure stray radiation and cooling requirements compare to calculation - long pulse tests in test-stand - mount DD-window to torus under discussion with KIT

22. 22J. Stober, EC17, Deurne, May 2012 Zoom on edge profiles (n e, T e, v tor ) With increase of ECRH frac. n e no change T e 10 % reduction T i no change v rot_tor_edge decrease (reduced torque input) v rot_pol_edge no change

23. 23J. Stober, EC17, Deurne, May 2012 Grooved disk too fragile (A. Vaccaro, KIT) Details: A. Vaccaro et al., Proceedings IRMMW 2011

24. 24J. Stober, EC17, Deurne, May 2012 Failure of double disk window Conditioning with increasing pulse length 3 s pulse with 620 kW successfull (#26271) 4.1 s pulse with 580 kW lead to failure (#26277) - Gyrotron switched of by inter-disk vac. control (5x10 - 4 mbar) - no arcs detected - water found in inter-disk volume - Effect of non-perfect beam ? - Operation with 2  inclination? Increase of stray radiation measured +7 db (post mortem). Steam-bubble in cooling channel?

25. 25J. Stober, EC17, Deurne, May 2012 Broken double disc window Air-side disk, light from behind

26. 26J. Stober, EC17, Deurne, May 2012 - minimum bandwidth 200 MHz must include frequency drift - accuracy of positioning < 5  m - needs evacuation  80 mm KIT double disc window

27. 27J. Stober, EC17, Deurne, May 2012 torus-window test facility 3 Mitre bends + wave guides movable mirror in load-MOU wave guide connector to load-MOU window test facility

28. 28J. Stober, EC17, Deurne, May 2012 torus-window test facility

29. 29J. Stober, EC17, Deurne, May 2012 Comparison NBI - ECRH [- ICRH] (F. Sommer et al.) 27247 : LSN, H-mode, I p ~ 1 Ma, B t ~ 2.5 T  q 95 = 4.0, n e ~ 9 x 10 19 m -3 Constant global Plasmaparameter: W mhd ~ 350 kJ, P rad ~ 1.5 MW, f ELM ~ 50 Hz, H 98 ~ 0.8, β N ~ 0.95, eff ~ 2 P total  3 MW 4 phases: -0 NBI 2.7 ECRH -0.8 NBI 2.0 ECRH -1.6 NBI 1.2 ECRH -2.4 NBI 0.6 ECRH