APS Logo

ELM suppressed high performance fusion scenarios achieved with Feedback Adaptive RMP ELM Control

ORAL

Abstract

We designed a Feedback Adaptive RMP ELM Controller [1] which, based on the detected ELM activity, changes the RMP such that ELM suppression is achieved. When applied to KSTAR, the controller was successful at obtaining, sustaining and optimizing ELM suppression where up to 60% [2] of the confinement degradation was recovered in feedback.

To eliminate all ELMs, additional capabilities are added, such as ELM suppression-loss precursor detection using Dα-emission. When the detector detects a precursor, an RMP pulse is applied. This mechanism demonstrated its ability to prevent imminent ELMs. As observed, the optimized RMP will change during long pulses because of plasma evolution. Since detailed models are too computationally expensive in real-time, an ML algorithm has been developed that determines the optimized spectrum in real-time. This could allow the controller to adjust significantly during long pulses, in a way where it sustains ELM suppression throughout.

[1] R. Shousha et al., Phys. Plasmas, 29, 032514 (2022).

[2] S. K. Kim et al., Nucl. Fusion, 62, 026043 (2022).

Publication: [1] R. Shousha et al., Phys. Plasmas, 29, 032514 (2022).<br>[2] S. K. Kim et al., Nucl. Fusion, 62, 026043 (2022).

Presenters

  • Ricardo Shousha

    Princeton University

Authors

  • Ricardo Shousha

    Princeton University

  • SangKyeun Kim

    Princeton University, Princeton University, U.S.A., PPPL, PU

  • Keith Erickson

    Princeton Plasma Physics Laboratory, PPPL

  • Jong-Kyu Park

    Princeton Plasma Physics Laboratory, Princeton Plasma Physics Laboratory, U.S.A., PPPL

  • SeongMoo Yang

    Princeton Plasma Physics Laboratory, Princeton Plasma Physics Laboratory, U.S.A., PPPL

  • Minwoo Kim

    Korea Institute of Fusion Energy, KFE, Korean Intitute of Fusion Energy

  • Giwook Shin

    Korea institute of Fusion Energy, Korea Institute of Fusion Energy, KFE

  • Sanghee Hahn

    Korea Institute of Fusion Energy, Korea institute of Fusion Energy, Korea Institute of Fusion Energy, Korea, KFE

  • Gunyoung Park

    Korea Institute of Fusion Energy, KFE

  • Y.M. Jeon

    Korea Institute of Fusion Energy

  • Nikolas C Logan

    Lawrence Livermore Natl Lab, LLNL

  • Egemen Kolemen

    Princeton University