National Fusion Research Institute a. Princeton Plasma Physics Laboratory

Transcription

1 Ko-Ja Workshop on Physics and Technology of Heating and Current Drive, Pohang, Korea, 2016 M. Joung, J. H. Jeong, J. W. Han, I. H. Lee, S. K. Kim, S. J. Wang, J. G. Kwak, R. Ellis a, J. Hosea a and the KSTAR Team National Fusion Research Institute a Princeton Plasma Physics Laboratory

2 Contents Introduction - Roles of ECH for KSTAR - Progress of KSTAR ECH System Overview and Operation results of New ECH system - Overview of ECH system - 105GHz(0.8MW)/140GHz(0.95MW), 300s Gyrotron - Evacuated 63.5mm corrugated waveguide components - Actively water-cooled antenna - Commissioning and operation results of ECH system - Operation results of ECH system in 2016 KSTAR campaign Future Plan and Summary 2

3 Role of ECH for KSTAR Since 2008, first plasma, ECH has been utilized as a main heating device. ECH main mission was the reliable startup and flux saving by on-axis heating. ECH being used as a tool for various physics experiments ( ) On/Off-axis heating for impurity control and transport study On/Off-axis CD used for MHD instability control (sawtooth, TM/NTM and etc.) On-axis heating and off-axis CD to achieve high performance and steady-state operation for KSTAR long pulse operation and remote control of ECH required NTM control ECH-assisted startup Long pulse discharge Fully non-inductive SS discharge Pulse Width [ms] KSTAR 1st plasma campaign ( ~ ) dummy loads moved near the gyrotron ( ) Beam Voltage & Current Date [YYMMDD] warm-up ( ) 3

4 Progress of KSTAR ECH System CPI (84GHz) 500kW, 2 s GYCOM (110GHz) 1MW, 2 s JAEA&Toshiba (170GHz) 1MW, CW GYCOM (105/140GHz) 950kW, 300s GY 84GHz/0.1MW/100ms(CPI) :pre-ionization, wall cleaning 110GHz/0.3MW/2s(GA-Gycom) :assisted start up 170GHz/0.6MW/50s(JAEA) :assisted start up, SS operation new 105/ &140GHz/1MW/CW(Gycom) :assist start up, SS operation TL PW Ant Evacuated 31.75mm corrugated waveguide Evacuated 63.5mm corrugated waveguide (1MW, CW) (ITER type) Inverter (70kV, 30A) Chopper type (60kV, 55A) PSM type (55kV, 55A) (ITER type) 500kW, 10s Cu plating Air motor 1MW, 10 sec Copper + SS DC motor 1MW, 20 sec 1MW, CW 2MW, CW?? All copper, focusing Copper + SS bar Melted Mirror Start control Formed bellows welded bellows Actively cooled FPGA 4

5 Contents Introduction - Roles of ECH for KSTAR - Progress of KSTAR ECH System Overview and Operation results of New ECH system - Overview of ECH system - 105GHz(0.8MW)/140GHz(0.95MW), 300s Gyrotron - Evacuated 63.5mm corrugated waveguide components - Actively water-cooled antenna - Commissioning and operation results of ECH system - Operation results of ECH system in 2016 KSTAR campaign Future Plan and Summary 5

6 Overview of New ECH System KSTAR Steady-state launcher (PPPL) - 1MW, CW operation with actively water cooled system - Two mirrors (fixed and focusing mirror and steerable mirror) - Real-time vertical position control N port at the same toroidal launcher angle - Scanning speed: 10 degree/sec Evacuated 63.5mm corrugated waveguide components (GA) - 1MW, CW operation at 105/140GHz - total length of about 60 m with 8 miter bends including two polarizer miter bends - 4 vacuum pumping systems - 1 waveguide gate valve, not used CVD window - Theoretical TL loss ~ 10% - Used water-cooled jackets Power supply and control system (DAWONSYS) - 3MW, DC high voltage PS in PSM type (128 modules) - CPS: 55kV/55A/60Hz - BPS: 40kV/150mA/5kHz - Fast high voltage switch on CPS and BPS - 60Hz modulation, 1 % ripple - ON/OFF control by PCS 105/140GHz gyrotron (GYCOM) MW(140GHz) and 800kW(105GHz) for 300 sec - Cavity mode: TE22,8(140GHz), TE17,6(105GHz) - Operating frequency changed by magnet polarity - Collector heat load: 1.1MW 6

7 High voltage power supplies 22.9kV incoming Cathode PS -55kV/55A, DC power supply PSM (Pulse Step Modulator) type (ITER type) Rising/falling time: <20 sec for each module Minimum regulating voltage: 0.5 kv Ripple: 1% (about 1.1 kv) Modulation with PSM: 60 Hz High Voltage Switch (HVS, opening switch) -55kV/55A Max. voltage: 100 kv, peak current: 100 A Off time: < 5 sec (gyrotron energy < 10 J) Body PS 40kV/200mA (8kW), DC power supply Model: Glassman (SH40R200) Voltage programming accuracy: ~ 0.5 % (~0.2 kv) Ripple: better than 0.025% of rated voltage Modulation with HVS and discharge switch: 0.1 Hz ~ 5 khz, duty: 10 ~ 90 % 22.9kV 50MVA EC2 MAIN VCB Main TR LEGEND ECH/CD1 Transformer Y-Y Transformer D-Y RETURN GROUND HIGH VOLTAGE PSM Stack #128 Stack #65 Stack #64 Stack #1 GND Switch KSTAR EC2 SINGLE-LINE DIAGRAM BODY HVDC TR PSM modules L=90M BPS Main GND Class 1 VDC BODY HVS TANK CPS-HVS CATHODE HVS TANK VK BPS-HVS IK VBODY IBODY GYROTRON CATHODE BODY COLLECTOR YARD & ELECTRIC ROOM 1 ST FLOOR 2 ND FLOOR Single line diagram for GPS Glassman SH40R200 7 Heater P/S Cathode Coil PS UP DC CCPS AC CCPS LO DC CCPS

8 63.5mm corrugated waveguide components, Transmission efficiency more than 90% 60m Waveguide 6 Miter bends and 1 diverted waveguide switch 105 GHz remark 140 GHz remark 0.05 db (1.2%) per 100 meters < 0.7%, including < 0.15% ohmic loss in mirror ~ 0.26% of the incident power is converted to modes near cutoff 0.02 db (0.5%) per 100 meters < 0.6%, including < 0.2% ohmic loss in mirror ~ 0.17% of the incident power is converted to modes near cutoff 2 Polarizers 1%, including 0.4% ohmic loss in mirror The ohmic loss depends on the polarization and the temp of the mirror 1%, including 0.6% ohmic loss in mirror The ohmic loss depends on the polarization and the temp of the mirror 1 Waveguide switch (into isolated) < 0.01% < 0.01% 1 Pumpout tee < 0.1% < 1W < 0.1% <1W 1 Waveguide gate valve < 0.1% < 0.1% 1 Waveguide bellows < 0.1% < 7W < 0.1% <7W 2 Waveguide adaptor ~0.015% ~0.01% Total loss 7.26% to KSTAR (5.97% to dummy) 6.23% to KSTAR (5.32% to dummy) 8

9 Actively cooled and real-time controlled launcher Launcher design parameters have been changed for high performance, steady state operation of KSTAR. It s upgraded for steady state operation and fast realtime control. Power Initial 1MW, 10 sec Present Near Future Goal 1MW, CW 1MW, CW 2MW, CW Side view Fixed Focusing mirror Shutter Steerable mirror 63.5 mm W/G ECW Toroidal scan Cooling Passive Water (bellows) Water (coiled)? Poloidal scan Poloidal 40 ~ 90 (-30cm to +60cm) 50 ~ 80 (-10cm to +40cm) 40 ~ 90 (-30cm to +60cm) 40 ~ 90 (-30cm to +60cm) R=1.8m Toroidal ± 38 ± 15 ± 20 ± 25 Motor Air motor DC motor Fast DC Fast DC Encoder Mechanical, 14bits Mechanica l, 14bits Magnetic, 24bits Magnetic, 24bits Speed 4 /sec 10 /sec 25 /sec 40 /sec Acc. ± 1 ± 0.1 ± 0.1 ± 0.1 I p B t ~ 50 Dia. 120 mm 100 mm 80 mm 60 mm 9

10 EC injection & mirror control by Plasma Control System (PCS) Power control system Pre-setting injection time & modulation period on PCS ECH power supply controller receive the signal from PCS. RF On signal in local ECH system should be ON during the time period. This time should be same as the time given by PCS. Main PCS Heating local control Room PCSrt5 Example #10682 Arbitrary waveform of ECH power ECH Power controller ECE EC beam vertical position scanning Mirror control system Operation mode should be PCS mode PCS can limit the mirror position by setting the upper and the lower limits. There are three ways to control the mirror. 1. pre-setting 2. tracking q value in real time 3. tracking normalized pshi value in real time 10

11 Measurements for steady-state operation Some parts of ECH system such as gyrotron, transmission line, antenna, were measured by calorimetry using RTD sensor (100 ohm). 22 Thermo-Couple sensors were installed on the transmission line to monitor the temperature of components. ECH T/L 3D Map 105/140GHz GYROTRON RTD Bellows RTD 20 Tee *For launcher 19 Power monitor Polarizers *Mirrors of launcher were cooled by water. RTD sensors were far from mirrors and installed at the manifold located about 10 meters from the mirrors. Flow rate was about 4.5 lpm and pressure about 4 bar. RTD Power monitor RTD 1 105/140GHz GYROTRON RTD 11

12 Contents Introduction - Roles of ECH for KSTAR - Progress of KSTAR ECH System Overview and Operation results of New ECH system - Overview of ECH system - 105GHz(0.8MW)/140GHz(0.95MW), 300s Gyrotron - Evacuated 63.5mm corrugated waveguide components - Actively water-cooled antenna - Commissioning and operation results of ECH system - Operation results of ECH system in 2016 KSTAR campaign Future Plan and Summary 12

13 Commissioning results of 105/140GHz gyrotron System Setup for gyrotron test About 6m W/G 3 miter bends With GYCOM pumping tee Used GYCOM dummy load 2% power reflected from dummy load Used water jackets TEST SETUP DUMMY MOU GYROTRON Gyrotron specification Gyrotron Power 800kW 950kW Pulse width 300s Mode TE17,6 TE22,8 Frequency Efficiency >35% >45% Output mode TL mode TEM00, >93% purity HE11, >97% purity Dummy 700kW 850kW 1 st event: Vacuum pressure increased 2 nd event: Oil cooling jacket between body and ground cracked MOU pressure 400kW, 150 sec Oil tank 3 rd event: Temperature increase at waveguide - Increased up to 100 C - Installed water jacket TEE pressure near the dummy load Cracked and deformed Teflon insulator Special water cooled w/g coupling and w/g jacket near MOU 13

14 Operation results to dummy load Test results into dummy load at full power ~ 850kW at 140GHz with heater boost Measured delta T at gyrotron and MOU collector 140GHz ~ 700kW at 105GHz without heater boost 300 sec anode MOU mirror Min window MOU body MOU abs. Successfully achieved the full power and the full pulse length of gyrotron at two frequencies Heater is controlled by voltage and heater boost is very simple method that increased the voltage about 10V after starting the oscillation of the gyrotron. Gyrotron vacuum was very stable and rapidly saturated taking about 5 sec. 105GHz 14

15 Gyrotron efficiency 140GHz Calorimetric power [kw] Fraction [%] For 140GHz 105GHz Calorimetric power [kw] Anode-cavity Collector Main window Relief window Relief load MOU bellows MOU body MOU mirror MOU absorber MOU body CW load CW load mirror sec 300sec Total For 140 GHz RF power ~ 800 kw Total cal. power: kw Input power: 1784 kw (Vcps=44.6kV, Ibeam=40A) Efficiency ~ 45 % For 105 GHz RF power ~ 700 kw Total cal. power: kw Input power: kw (Vcps=44.6kV, Ibeam=34.2A) Efficiency ~ 46.9 % 15

16 Waveguide temperatures from MOU to dummy 140GHz Add another water cooling jacket MOU flange: up to 72 C ~200s 300s 105GHz 300s MOU flange: up to 120 C st w/g before MB after MB pumpout tee near dummy 86 C 16

17 Vacuum pressure in TL from MOU to dummy 140GHz, 300s, 850kW mbar 140GHz, 50s, 850kW 105GHz, 300s, 700kW MOU with TMP nd Miter bend near Dummy TMP for dummy mbar MOU with TMP nd Miter bend near Dummy TMP for dummy 17

18 Contents Introduction - Roles of ECH for KSTAR - Progress of KSTAR ECH System Overview and Operation results of New ECH system - Overview of ECH system - 105GHz(0.8MW)/140GHz(0.95MW), 300s Gyrotron - Evacuated 63.5mm corrugated waveguide components - Actively water-cooled antenna - Commissioning and operation results of ECH system - Operation results of ECH system in 2016 KSTAR campaign Future Plan and Summary 18

19 KSTAR long pulse discharge using ECH system Long-pulse high betap discharge with reduced P NBI Slow increase of V loop due to movement of strike point in t H-mode > 1 min. long-pulse operation Main issue was a limiter temperature increase. Longest pulse of ECH (800kW, 71 sec) ECH was perfect. If ECH is not injected, this discharge would be terminated. For this shot, EC resonance position and vertical position was adjusted in 0.1T and 1cm step. 19

20 Operation results of ECH system to KSTAR P EC ~ 800 kw V BPS ~ 23.0kV V CPS ~ 44.6kV I CPS ~ 45.9/38A I BPS ~ 8.2mA I VACION ~ 6 A KSTAR (140GHz ECH) KSTAR (140GHz ECH) dt steering dt window dt fixed dt collector 60.5 sec case About 10 C rise dt relief load T miter bend (in/out) T polarizer (in/out) T bellows (in/out) For long pulse discharge, simple heater boost was used. RF power and gyrotron pressure were very stable. Calorimetric power at the steering mirror is about 1.26 kw (=0.0697*4*4.5lpm). This value corresponds to the steering mirror design value absorbed about 0.12% by mirror. It is adding the heat flux from the plasma about 0.3 kw. 15 C sec, 800 kw, 140GHz 20

21 NTM suppression using ECCD Ip*100 NBI ECH ON by NTM category ON ECH ECH OFF N Mode amplitude Supp. Amp. Sat. Amp. Real-time NTM suppression Algorithms were implemented in PCS and tested Tearing mode (2/1 & 3/2 modes) generated at 3.4 MW NBI in H-mode ECH power and mirror controlled by Search & suppress algorithm based on mode amplitude (active q-tracking algorithm can be used before and after) Depending on the algorithm, Mirror position Mirror stop 21

22 Contents Introduction - Roles of ECH for KSTAR - Progress of KSTAR ECH System Overview and Operation results of New ECH system - Overview of ECH system - 105GHz(0.8MW)/140GHz(0.95MW), 300s Gyrotron - Evacuated 63.5mm corrugated waveguide components - Actively water-cooled antenna - Commissioning and operation results of ECH system - Operation results of ECH system in 2016 KSTAR campaign Future Plan and Summary 22

23 Future Plan ECH layout in 2018 In 2018, ECH power will be doubled. In the next campaign, there is no change in the heating power. But, EC launcher will be improved in EC beam size and scanning angle. After 2017 campaign, ECH port will be moved to O-port for 6 MW ECH in a single port. 4-Gyrotrons frequency and manufacturer should be decided within the first half of And finally ECH is needed a new room for 6MW. ECH ECH Newly assigned port (O-port) for 6MW ECH Be moved after 2017 campaign 6-beam launcher 23

24 Summary New ECH system was commissioned for long time because of several events, but we successfully achieved the full power, about 1MW, and the full pulse length, 300s, at both frequencies of ECH system using dummy load before the campaign. In 2016, ECH was only one system. We switched ECH frequency in the middle of campaign and mainly used 140GHz ECH due to density cutoff of 105GHz ECH. Newly developed dual frequency ECH system was working well and assisted the KSTAR experiments successfully at both frequencies. ECH would be continuously upgraded in power of up to 6 MW and needed the design studies of power supply, launcher, waveguide, and so on for the high performance, steady state operation of KSTAR and for decreasing the cost. 24

25 Thank you for your attention! Mi Joung

26 Event: 105 GHz EC2 Injection without Plasma Estimated temperature at 6 sec Faraday shield : 594 Divertor : 607 ECH 600kW, 6 sec

27 # long pulse 15 C sec, 800 kw, 140GHz 27

28 ECH assisted start-up using TPC (trapped particle configuration) 28

29 Other ECH control Typical H-mode High density Higher density Large toroidal angle 105 GHz, Gtor=10deg, n 0 =3.4x10 19 /m 3, B T =1.8T 105 GHz, Gtor=10deg, n 0 =8.4x10 19 /m 3, B T =1.8T 140 GHz, Gtor=10deg, n 0 =10x10 19 /m 3, B T =2.2T 140 GHz, Gtor=20deg, n 0 =10x10 19 /m 3, B T =2.2T Needed the automatic system to find the target position of ECH in the plasma in real time 29