Real time control of plasma performance on ASDEX upgrade and its implications for ITER

Sustained burning plasma operation is the primary target of thermonuclear fusion research and development. To generate economically viable electricity from nuclear fusion requires a high reaction rate over long times with high reliability. Plasma performance must continue to improve above the current levels to reach this target. Non-linear stability limits and internal couplings make optimization of plasma performance a complex, convoluted task, which can be mastered only by assistance of automated control tools. The ASDEX Upgrade fusion experiment has a long tradition in the exploration of physics relations and the subsequent derivation of control strategies. Based on examples from current projects, radiative cooling, NTM stabilization and ELM mitigation, we show typical facets of performance control and how they are implemented by the ASDEX Upgrade Discharge Control System (DCS). Finally, we explain how the methods could be further developed and which additional features would be necessary in the ITER context.