ASDEX Upgradeʹs new plasma control scheme

ASDEX Upgrade is a medium sized tokamak experiment investigating highly shaped plasma and advanced scenarios to be extrapolated for ITER. Eleven independent magnetic coils allow for proper shaping and plasma current control. For plasma heating and current drive eight NBI beam lines, two ICRH antenna pairs and four ECRH gyrotrons are available. Five channels for controlling gas valves and a pellet injector serve for fuelling. All actuators are driven by a digital discharge control system. One basic enhancement of the latest generation is a unified framework for all feed-forward and feedback control tasks in a discharge. amework consists of two layers. The core layer implements wind-up safe feedback controllers with a collection of overlaid output limitations. Each controller is dynamically switchable in references, controlled variables, control law and control parameters via a control mode. The coordination layer implements intelligent discharge protection or optimisation algorithms, which synchronously can change control modes and dynamically can generate reference waveforms adapted to the dischargeʹs state and goal. the framework approach easily allows for further extensions and opens a door for future experimental investigations.