ACTIVE DENSITY CONTROL WITH ERGODIC DIVERTOR AND PUMP LIMITERS ON TORE-SUPRA

Active plasma density control with the ergodized boundary layer has be en achieved in Tore Supra with the plasma leaning on the ergodic diver tor and on the vertical pump limiters. Ohmic experiments are reported which show that active pumping yields a satisfactory exhaust capabilit y. It is also shown that the wall particle content is partially deplet ed by the active pumping and that no modification of the radiated powe r fraction is recorded with active pumping. Plasma density control can be achieved with 70% of radiated power in steady state with intrinsic impurities, but when the radiated power reaches 100%, the plasma dens ity cannot be actively controlled.