RECENT PROGRESS AND UPGRADE PLAN OF KTX REVERSED FIELD PINCH

Recent works on Keda Torus eXperiment (KTX) focused on operation capabilities upgrade. The upgrade design details of the main ohmic power supply, the equilibrium field power supply and the edge active feedback control system have been completed. The electronic system and fast control power supplies of the active feedback control system are under test. The capacitor banks and switching elements of the main power supply for upgrade have been put into production. Advanced diagnostics for 3D physics research, including the terahertz interferometer, double-foil soft x-ray imaging, edge capacitive probe and multi-channel spectrograph system, have been developed for the normal operation and physical analysis at present stage. Based on the present power supply system, the maximum plasma current can reach 300kA and the during time of reversed field pinch state is approaching 3ms. Magnetohydrodynamic (MHD) activities in the ultra-low q configuration are investigated experimentally to explore the plasma self-organization phenomena on KTX device in the current state of operation. The characteristics of various quasi-single helicities (QSHs) in KTX are also investigated in ideal MHD simulations with helical equilibria.

[1]  W. Mao,et al.  Three-dimensional characteristics of the quasi-single helical state in the KTX , 2020, Nuclear Fusion.

[2]  W. Ding,et al.  Optical fiber interferometer application for high electron density measurements on compact torus plasmas. , 2020, The Review of scientific instruments.

[3]  W. Ding,et al.  Error field feedback control system in the Keda Torus eXperiment and open loop control experiment , 2020 .

[4]  W. Ding,et al.  Bolometer measurements of the radiated power and estimates of the effective ion charge Z on the Keda Torus eXperiment , 2020 .

[5]  Jinlin Xie,et al.  Fast radial scanning probe system on KTX , 2020 .

[6]  W. Ding,et al.  A parametric method for correcting polluted plasma current signal and its application on Keda Torus eXperiment. , 2019, The Review of scientific instruments.

[7]  W. Ding,et al.  An automatic beam alignment system based on relative reference points for Thomson scattering diagnosis system. , 2019, The Review of scientific instruments.

[8]  W. Ding,et al.  Construction of an ${{\rm{H}}}_{\alpha }$ diagnostic system and its application to determine neutral hydrogen densities on the Keda Torus eXperiment , 2019, Chinese Physics B.

[9]  W. Ding,et al.  An overview of diagnostic upgrade and experimental progress in the KTX , 2019, Nuclear Fusion.

[10]  Ge Zhuang,et al.  MHD Mode Analysis Using the Unevenly Spaced Mirnov Coils in the Keda Torus eXperiment , 2019, IEEE Transactions on Plasma Science.

[11]  W. Ding,et al.  Forward Scattering Measurement Based on Terahertz Microwave Interferometer on KTX Reversed Field Pinch , 2019, IEEE Transactions on Plasma Science.