A5033492615- Magnetic confinement fusion research
- Superconducting Materials and Applications
- Particle accelerators and beam dynamics
- Ionosphere and magnetosphere dynamics
- Advanced Photonic Communication Systems
- Mechanical and Optical Resonators
- Laser-Plasma Interactions and Diagnostics
- Transportation and Mobility Innovations
- Advanced Optical Network Technologies
- Induction Heating and Inverter Technology
- Electromagnetic Compatibility and Noise Suppression
- Solar and Space Plasma Dynamics
- Fusion materials and technologies
- Transportation Planning and Optimization
- Physics of Superconductivity and Magnetism
- Urban and Freight Transport Logistics
- Advanced DC-DC Converters
- Optical Network Technologies
- Advanced Fiber Laser Technologies
- Advanced Fiber Optic Sensors
Huazhong University of Science and Technology
2018-2024
Shanghai Electric (China)
2024
Abstract The coupling of multiple magnetohydrodynamic (MHD) modes can lead to mode locking and major disruption in tokamak plasmas. In the J-TEXT tokamak, between two small modes, i.e. m / n = 2/1 3/1 ( are poloidal toroidal numbers, respectively), appears when edge safety factor is reduced vicinity 3. After coupling, phase difference equals 0 low field side midplane. This relation coupled leads mutual destabilization even disruption. A control scheme avoid caused by resonant magnetic...
Abstract The spectrum effect on the penetration of resonant magnetic perturbation (RMP) is studied with upgraded in-vessel RMP coils J-TEXT. poloidal field, especially amplitudes 2/1 and 3/1 components, can be varied by phase difference between upper lower coil rows, Δ ϕ = top − bottom , where are toroidal phases n 1 field each row. type found to related including either or successive penetrations followed RMP. For cases only one component, thresholds measured corresponding component close...
Plasma major disruption is one of the most critical issues to be solved for a tokamak fusion reactor. Experiments prevent mode locking and subsequent disruptions have been carried out on J-TEXT using rotating resonant magnetic perturbations (RMPs). The tearing modes, locked lead without applying RMPs, can accelerated by RMPs RMP frequency. As result, are delayed or prevented. effects amplitude frequency prevention investigated.
Abstract The phase difference Δ ξ between locked islands (2/1 and 3/1) has been found to influence the heat transport on thermal quench during disruptions by numerical modeling [Hu Q et al 2019 Nucl. Fusion 59 , 016005]. To verify this experimentally, a set of resonant magnetic perturbation (RMP) coils is required excite coupled with different . spectrum analysis shows that current RMP J-TEXT can only produce sufficient 2/1 3/1 fields limited ∈[−75°, 75°]. In order broaden adjustable range...
This paper focuses on the comparison of characteristics among three different types high temperature superconducting (HTS) transformers. The iron core structures HTS transformers are air core, partial and full core. cores made oriented silicon steel sheets. primary windings four layers connected in series, secondary nine double pancake coils parallel. Fundamental tests, such as critical test, no-load test load performed environment liquid nitrogen. current nonuniformity also confirmed by...
Abstract It has been found that a higher-frequency rotating resonant magnetic perturbation (RRMP) can suppress large tearing mode (TM) and avoid subsequent disruption (Li et al 2020 Nucl. Fusion 60 056022). To clarify the mechanism of stabilizing effect RRMP, experiments on effects RRMPs with different frequencies TM amplitude are presented in this paper. After eliminating destabilizing statistical analysis reveals notable negative correlation between changes frequency. Further investigation...
A new method to suppress tearing mode and accelerate magnetic island rotation has been explored. To verify this on the J-TEXT tokamak, a current-pulse power supply is designed drive resonant perturbation coils with frequency range from 1 5 kHz amplitude of 3 kA, which can create 0.75 G perturbation. The topology modified by H-bridge inverter, bipolar pulsed current. set boost capacitors an isolation diode added dc bus just before inverter. During current changing time, store energy inductive...
The ac power supply system of the magnetic island divertor coil is widely applied to reduce peak thermal load boundary target plate. It was found that this should have current frequency in range 0-100 Hz and amplitude 5 kA at 100 Hz. In article, a new main circuit proposed for variable-frequency system. consists six-pulse, thyristor rectifier parallel, H-bridge inverter. control strategy applies carrier phase-shifted, sinusoidal pulsewidth modulation (CPS-SPWM) form an almost calculate LC...
Abstract The acceleration of the magnetic island rotation by modulated resonant perturbation (MRMP) has been studied in J-TEXT tokamak experiments. After applying MRMP, phase difference between tearing mode (TM) and Δ ξ , oscillated near effective difference, eff which was defined as time averaged value . When closed to the— π /2, MRMP only contributed an accelerating torque on TM. As result, TM frequency increased a few kilohertz for optimized relative small RMPs order 10 −5 toroidal field...
The rotating resonant magnetic perturbation (RMP) could lock the tearing mode (TM) and prevent disruption. It is found that TM instantaneous frequency oscillates during locking on RMP. In this work, oscillation was derived analytically based toroidal torque balance, which verified experimentally. two peaks with higher (2fTM0-fRMP) lower (fRMP) occurred in spectrum when window width of FFT shorter than oscillating period. Those were explained description frequency. independence temporal...