The plasma current profile during current reversal in AC operation of the CT-6B tokamak

Huang, Jianguo; Yang, Xiaomin; Shaobai, Zheng; Chi, Feng; Zhang, Houxian; Long, Wang

doi:10.1088/0029-5515/40/12/306

Cited by 20 publications

(13 citation statements)

References 13 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…What are the plasma density, current and temperature profiles with zero current? A very good experiment on the CT-6B tokamak was done for measuring the plasma current density profile [10]. By using two internal magnetic probes which were inserted into the plasma during plasma discharges on a shot-by-shot basis, the plasma current distribution was reconstructed.…”

Section: Discussionmentioning

confidence: 99%

“…ISTTOK achieved a multi-cycle alternating square wave plasma with seven half-cycles, no dwell time and a plasma current of 4-5 kA [8]. Constant ac discharges with 2, 4 and 8 sinusoidal cycles of 4 kA were obtained on the CT-6B tokamak [9,10]. Due to the toroidal field duration limit, most ac operations were very short and plasma parameters were relatively low.…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Quasi-steady-state ac plasma current operation in HT-7 tokamak

Luo²,

Wang³

et al. 2007

Nucl. Fusion

View full text Add to dashboard Cite

A quasi-steady-state alternating current operation assisted by lower hybrid wave (LHW) was achieved on a HT-7 superconducting tokamak with plasma current of I p = 125 kA, line-averaged density of 1.5 × 1019 m−3, electron temperature of T e = 500 eV and 30–50 s plasma duration. Plasma current was sustained and smoothly transferred from one direction to the other without loss of ionization. Plasma position control, LHW assistance, strong gas puffing and good wall condition are the key issues to have a smooth transition of plasma current. Our modelling results show that current reversal equilibrium configuration with two oppositely flowing currents in the high-field-side and the low-field-side during current reversal exists. This is in agreement with experimental measurements.

show abstract

Section: Discussionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Quasi-steady-state ac plasma current operation in HT-7 tokamak

Luo²,

Wang³

et al. 2007

Nucl. Fusion

View full text Add to dashboard Cite

show abstract

“…These configurations are closely related to the current-hole regime observed in large tokamak experiments [6,7]. Although the ac experiments in low-temperature plasmas clearly show the formation of two large magnetic islands with opposite currents during the current reversal phase [8], the magnetic topology in the plasma core of current-hole experiments remains unresolved. It is not even clear if the toroidal current reverses in the core of current holes, as further experiments indicated a nearly zero current clamping in the central region [9,10].…”

Section: Introductionmentioning

confidence: 58%

Tokamak equilibria with strong toroidal current density reversal

Ludwig¹,

Rodrigues²,

Bizarro³

2013

Nucl. Fusion

View full text Add to dashboard Cite

The equilibrium of large magnetic islands in the core of a tokamak under conditions of strong toroidal current density reversal is investigated by a new method. The method uses distinct spectral representations to describe each simply connected region as well as the containing shell geometry. This ideal conducting shell may substitute for the plasma edge region or take a virtual character representing the external equilibrium field effect. The internal equilibrium of the islands is solved within the framework of the variational moment method. Equivalent surface current densities are defined on the boundaries of the islands and on the thin containing shell, giving a straightforward formulation to the interaction between regions. The equilibrium of the island–shell system is determined by matching moments of the Dirichlet boundary conditions. Finally, the macroscopic stability against a class of tilting displacements is examined by means of an energy principle. It is found out that the up–down symmetric islands are stable to this particular perturbation and geometry but the asymmetric system presents a bifurcation in the equilibrium.

show abstract

“…10. The existence of the flux surface and rotational transform provides the particle confinement during the current reversal [21].…”

Section: Ct-6b Experimentsmentioning

confidence: 99%

Overview on the progress of tokamak experimental research in China

et al. 2001

Self Cite

View full text Add to dashboard Cite

Tokamak experimental research in China has made important progress. The main efforts were related to quasi-steady-state operation, LHCD, plasma heating with ICRF, IBW, NBI and ECRH, fuelling with pellets and supersonic molecular beams, and first wall conditioning techniques. Plasma parameters in the experiments were much improved, for example ne = 8 × 10 19 m −3 and a plasma pulse length of >10 s were achieved. ICRF boronization and conditioning resulted in Z eff close to unity. Steady state full LH wave current drive has been achieved for more than 3 s. LHCD ramp-up and recharge have also been demonstrated. The best η exp CD ≈ 0.5(1 + 0.085 exp(4.8(BT − 1.45)))neICD Rp/PLH = 10 19 m −2 A W −1 . Quasi-steady-state H-mode-like plasmas with a density close to the Greenwald limit were obtained by LHCD, where the energy confinement time was nearly five times longer than in the ohmic case. The synergy between IBW, pellet and LHCD was tested. Research on the mechanism of macroturbulence has been extensively carried out experimentally. AC tokamak operation has been successfully demonstrated.

show abstract

The plasma current profile during current reversal in AC operation of the CT-6B tokamak

Cited by 20 publications

References 13 publications

Quasi-steady-state ac plasma current operation in HT-7 tokamak

Quasi-steady-state ac plasma current operation in HT-7 tokamak

Tokamak equilibria with strong toroidal current density reversal

Overview on the progress of tokamak experimental research in China

Contact Info

Product

Resources

About