J. Plasma Fusion Res. SERIES, Vol.5 (2002) 106-111

Magnetic Confinement Fusion Research in Ghina
YUAN xi Wan
Institute of Plasma Physics, Chinese Academy of Sciences
P.O. Box 1126 Hefei Anhui 230031 P.R. China(Received: 11 December 2001 / Accepted: 8 May 2002)

Abstract
China will face to serious energy problems in near future and the magnetic confinement fusion
research is getting more support. SWIP and ASIPP are two largest research centers for the research. Five
tokamks (HT-7, HL-IM, HT-6M, KT-5 and CT-6) are running and many experimental progresses havebeen achieved. Three new projects have been approved and the new facilities (HT-7U, HL-2A andSUNIST) are under construction.

Keywords:
energy, China, magnetic confinement fusion research, tokamak

2. Organization and Facilities

1. lntroduction

Southwest Institute of Physics (SWP) which now
belongs to the National Committee of Defense Sciences
and Industry of China and Institute of Plasma Physics

With the rapid socio-economic development during
last l0 to 15 years in China the magnetic confinement
fusion research is getting more and more support via
different channels by the government. Three new(ASIPP) which belong to the Chinese Academy ofSciences are two largest research centers for themagnetic confinement fusion research in China.The

projects have been approved and the new facilities areunder construction. The research budget for magnetic
confinement fusion research is increasing smoothly year
by year. The number of graduated students also
increases rapidly with the reformation of education
system in China. Because China will face to more
serious problems on the shortage of energy and thepollution of the environment in near future with therapid economic development, the government now ismain facility in ASIPP is the medium sized
superconducting tokamak HT-7 (Fig. l). Its main
purpose is to explore high performance plasma
operation under steady-state condition. The machineruns normally with 1o = 150 KA, Br = 2T, R = t22 cm
and a = 27.5 cm [1,2]. Another small tokamak HT-6M
with 1o = 100 kA, Br = 1.5 T, R = 90 cm, a = 20 cm in
ASIPP is used to study ICRF and transport. The facility
in SWIP is tokamak HL-IM (Fig. 2). It is a medium
sized tokamak with Rs = l.O2 m, a = 0.26 m and Bt = 3T in circular limiter configuration. Its objectives are toconduct experiments on high power auxiliary heating

very interested in the prospect of magnetic fusion
research, especially the tokamak research. The
govemment is also interested in the further information
about ITER. Many high level officers of the government
have visited both SWIP and ASIPP. Two institutes aremaking effort together to promote China to participate
in the ITER program by some way if it will be
constructed in the near future.

and current drive and to explore new fueling techniques
in order to develop the physics and technology for next
generation tokamak [3].

@2OO2by The Japan Society of Plasma
Science and Nuclear Fusion ResearchCorresponding author's e-mail: wanyx@ mail.ipp.ac.cn
106Yuan X.W., Magnetic Confinement Fusion Research in China

Fig. 1 HT-7 superconducting tokamak

Fig. 3 KT-5 tokamak in USTC

Fig. 2 HL-1M tokamak in SWIP

Fig.4 CT-68 tokamak in IPCAS

significantly and the stable region in the Hugill diagram
was extended by the new type of wall conditioning andOther two small tokamaks are KT-5 (Fig. 3) in theUniversity of Sciences and Technology of China(USTC) in Hefei and CT-6B (Fig. a) in the Institute ofBoronization (Fig. 5) t4l.

Physics, Chinese Academy of Sciences (IP/CAS,For the long pulse discharge and future steady-state
operation on supercoducting tokamak the LHCD systemwith 1.2 MW (CW) and 2.45 GHz have been bult andtested. Using these system the long pulse discharges
with higher performace and plasma current fully driven
by LHW for more than 3 seconds have been achieved(Fig. 6). The ramp-up of plasma current by LHW, which
will be very important to set-up the plasma current by aBeijing), Both of them are operated for edge turbulence/transport study and alternative concept development.

3. Main Experimental Progresses onExistant Devices
3.1 HT-7 Tokamak Experiments
The stable continuous operation for l-3 months
during each campaign has been achieved on HT-7
superconducting tokamak Il,2). A new type of wallconditioning and Boronization and Siliconization using
ICRW instead of the glow discharge or Taylor discharge
have been well developed. It is easy to get high quality
film of Boron or Silicon with very high efficiency tocontrol impurity and to decrease the loop voltage andrecycling. The perfomance of discharge was improved

non-inductive current on superconducting tokamak, wasalso acheived (Fig.7) t5l.
Effective IBW heating with 300 kW (CW) RFsystem has been demonstrated (Fig. 8) [6]. Gas puffing,pellet injection and supersonic beam injection have beenused for plasma fuelling and density control. A real-time
multivariable control system has been developed for thefast equilibrium control. Combining above efforts thero7

Yuan X.W., Magnetic Confinement Fusion Research in China10080The film on C base after 250 shots-.-.€E$-.
-x-x-xojj_x_-e=60

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5ooo After RF siliconiztion

c2000-i i::rr"il-:ii"=1it,==,:
100
200
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Deposition depth {nm )Fig. 5 High efficiency and quality Boronization using ICRW and Extended Hugill diagram

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Fig. I Plasma off-axis heating by IBW forms a ITB-Iike
profle in SX emission, OH- 0.27

Fig. 6 Long pulse high performance plasma discharge

sustained by LHCD

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f1!::{r'll2ll-.rXt'o+

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Fig. 7 Plasma current ramp-up by LHCD

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4EIt [slFig.9 Repeatable 10 seconds discharges
108l0Yuan X.W., Magnetic Confinement Fusion Research in China

long pulse discharge with several seconds and thelongest one w;th 10.7 seconds on HT-7 can be easily

and the MHD activities were supressed significantly.
The double sawtooth in soft X-ray radiation wereachieved (Fig. 9).

observed (Fig. l0) [7]. The new fueling techniques withpellet injection and supersonic molecular beam injection(SMBI) were also employed to significantly improve the3.2 HL-1M Experiment

On HL-1M, plasma performance was greatly

energy confinement time and density limit. The fuelling

improved through the use ofboronization, siliconizationand lithiumization [3]. The maximum parameters
obtained in Hl,-lM ohmic heated plasmas are: Ip- 32O
kA, n" = 8 x lCt1e m-3, Br= 2.8 T. ICRF at a power levelof SMBI has been improved in the HL-IM tokamak
recently and a simple model of "cold injection path"
during the SMBI has been proposed, which is supported
by measurements of the edge temperature (7"), density(2"), Hu intensity profile (OF9, OFl 1) and HCN average
electron density as shown in Fig. 11 [8].

of 0.3 MW, NIII at a power level of 0.4 MW, ECRH ata level of 0.3Ct MW and LHCD at a power level of 1
MW have been carried out. By the off axis ECRH, theelectron temperature increased from 450 eV to 750 eV

3.3 KT-SC Experiment
On KT-5C tokamak (R = 32.5 cm, a = I2.5 cm, Io=10-20 kA) the interesting results of fluctuation andtransport investigation in the edge of plasmas have beenobtained. The suppression ofthe turbulent transport withthe change of the radial electric field E, induced by thebiased electrode is observed. It is found that the poloidal
flow contributes to the main part of the Er. The change

O. ETof the poloidal flow has a lead of about 20 ps to theO. TEformation of E as shown in Fig. 12. It suggests that aO. EB:- lEradial current responding to the biasing voltage drives aLOE

poloidal flow, which in turn drives the radial electricfield.

o. 99
a5E

3.4 CT-6B Experimentt_ E5

In the AC operation experiments on CT-6B

11155455T

5{Ol{tt{Etokamak, the plasma current profile and the flux surface
during the current reversal have been reconstructed anda novel method of the electron cyclotron wave current

Fig. 10 Double sawtooth in soft X-ray radiation during
ECRH

startup was demonstrated (Fig. l3).

200100=z900358-100
a 200olz

0290>Zd'0; 2Q>
1nIErro100

3-o-10gF,,':..'; 2.6"5 2.4t0t.6'7w* z.z 760-)^9800

840880T(ps)44t)

Fig. 12 Temporal evolution of the electrode voltage %Time(ms)and current /", radial electric field E, poloidal
ratio dC" and toroidal velocity u6 dt r= 7.5 cm.

Fig. 11 Edge Plasma Parameters during SMBI
109

Yuan X.W., Magnetic Confinement Fusion Research in China

3. New Proiects and Facilities which isUnder Gonstruction
Chinese government has approved a newsuperconducting tokamak HT-7U as a national50!10

important research facility [1]. Main parameters of HT7U are Br= 3.5 T, R6= 1.75 m, a=0.4 m, elongation r(b/a) = l-2, Io= I MA, PLH.D - 3.5-4 MW, Prcnn = 3-4fP$ 'ro

MW and maximum pulse length will be 1000 seconds(Figs. 14, 15). The main purpose of HT-7U is widely toinvestigate both the physics and technology for steadystate and advanced tokamak. The physics design and the:10R(* )o's

0,6$ xfn)

engineering design of HT-7U have been completed.
R&D activities and the most of fabrication, construction
and assembling works of HT-7U are under way inRussia, in workshop of ASIPP and Industry Company inChina. HT-7U will be completed around 2003 year.

Fig. 13 The plasma current distribution during the total
current passes zero in CT-6B tokamak.

m150

IM50s
-50-IW-150-2ffi

il l@lSmmW S0{frcmFig. 14 HT-7U tokamak-250

Fig. 15 Typical configuration of HT-7UFig. 16 HL-2A tokamak in SWIP110

Yuan X.W., Magnetic Confinement Fusion Research in China

In SWIP }{L-2A tokamak based on original
ASDEX main components is under construction (Fig.
16) t9l. HL-2A project is the extension and the

2.8 T, Rs = 1.64 m, a = 0.4 m, rc (bla) = t-t.3, Ip = 0.48
MA, PLHSD= 3 MW, Prcnu= 3 MW, PscnH= 1 MW,continuation of HL-lM tokamak and its main mission isobtaining experiences on divetor plasma and elongatedplasma control. The main parameters of HL-2A ore 81 =commissioning will be at the first half of next year. HL2A will be upgraded to HL-2M in future.
SUNIST is the university scale conceptual sphericaltokamak (Fig. 17, 18 ) t101. Parameters are R6= Q.l 6,a - 0.23 m, aspect ratio A > 1.3, rc (bla) -1.6, 8t = 9.15
T, 1o = 0.05 MA, central rod current lnop = 0.225 MAand flux swing - 0.06 Vs.
It is under construction in Qinghua University andwill be completed at first half of 20O2.

PNsr = 3 MW. The construction is on schedule and thePossible Future Plane
At first Chinese magnetic confinement fusion
community will joint together to promote to participate
in the ITER program if ITER will be constructed finally.
Secondly a hybrid test tokamak reactor may be proposed

around 10 years late if HL-2A and HT-7U are fullsuccess. Related research activities are under wav.

[]

References
Yuanxi Wan, HT-7 team and HT-7U team, Nucl.

Fusion 40. 1057 (2000).
tzl HT-7 team, presented by J.K. Xie, 18'n IAEA Inter.
Conf. on Plasma Physics and Controlled Nuclear
F us ion Re s e arc h, IAEA-CN-77 -OV I 4.
t3l Y. Lrru et a/., "Recent Experiement progress on theHL-IM Tokamak" EXPL/I2 IAEA Confernce 2000.
t4l J.Li et cl., Nucl. Fusion 39,973 (1999).

Fig. 17 Main components of SUNIS

t5l G.L. Kuang et al., ITth IAEA conference onfusionen e rgy,Y okahama, Japan.

t6l Y.P.Zhao et al.,"Ion Bernstein Wave Heating Experiments in HT-7 Superconducting Tokamak"
EXP4/30 IAEA Confernce 2000.
17l

E.Y. WANG, "Reversed magnetic shear experi-menrs in HL-lM", EXP5/08 IAEA Confernce 2000.
t8l L. YAO et a/., Nucl. Fusion 3E, 631(1998). EXP4/13 IAEA Conference.
YongLiu and HL-2A Team, Report on HL2A Extelperimental Program.

[10] Yexi He, Report on Status of SUNIST SphericalFig. 18 Calculated magnetic surface of SUNISTTokamak.

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