Electron cyclotron heating assisted start-up experiments in J-TEXT

Electron cyclotron heating (ECH) breakdown and burn-through assist has been adopted to make the ITER start-up, which uses a low toroidal electric field of about 0.3 V/m, more robust. Related studies have carried out on many fusion machines such as DIII-D, JT-60U, Tore Supra FTU. However, required ECH power ensure an effective at is not yet clear. Experiment was also performed in J-TEXT determine minimum requirements develop better physics description process. The loop voltage for successful shot reduced from 34 3.7 V (corresponding 0.56 V/m) by 300 kW X2-mode power. critical formation tokamak discharge 200kW, below this value, ionization caused observed, however, start-up does succeed. effect different voltages pulse-width studied. As injecting proper time, can achieve similar pre-ionization result case with high Extremely leads higher later when putting capacity continue discharging J-TEXT. earlier shutdown failed discharge.