Abstract. Limited available pellet velocities so far restricted the plasma performance of the efficient launch scheme from the tokamak magnetic high field side. Although pellet injection during H-mode results in more peaked density profiles and enhanced performance with respect to gas puff refuelling, prompt particle and energy losses induced by pellet induced ELM bursts still limited the operational area. An improved pellet injection set-up applied at ASDEX Upgrade allowed for the first time significantly higher injection velocities. In first proof-of-principle plasma discharges a successful scan of pellet injection at v = 240-1200 m/s and plasma parameter studies at v = 560 m/s were completed. They resulted in deeper penetration and particle deposition mitigating fast particle and energy losses. Further extension of tokamak operation in the high density regime seems feasible.
IAEA 2001