Analysis of the Vertical Field on EAST for Long-Pulse H-Mode Discharges

The connections among plasma current I
_p
, temperature T
_ei
, density ne, and vertical field B
_v
are derived for tokamaks and found that B
_v
has a linear and reversed linear relation with I
_p
. The linear term of Ip has a dominant influence on the vertical magnetic field strength B
_v
on # 73999 shot of Experimental Advanced Superconducting Tokamak (EAST)- the longest pulse of 101.2-s H-mode discharge since tokamak invention in the 1950s. The increase in the vertical field is a major method to compress the plasma volume, as occurred slightly in the EAST experiments. The parameter evolutions of EAST #73999 and #41195 are presented with the B
_v
-related magnetic compression (MC) parameters, and MC processes during L-mode and H-mode discharges are analyzed. The results of the analysis show that the energy confinement time of plasma agrees well with the scaling law of International Thermonuclear Experimental Reactor (ITER) and the fusion triple product is improved in the modest compression characteristic time.