Ion Cyclotron Heating control framework for ITER Plasma Control System: Simplified control-oriented models and preliminary control functions

The development of the Plasma Control System (PCS) for ITER relies on control oriented models that enable rapid simulation while capturing the key off-normal operational scenarios. This work presents a dedicated framework to support Ion Cyclotron Heating (ICH) control design and validation within the PCS. The framework incorporates simplified models of the ICH plant, ion cyclotron wave–plasma coupling, and the impact of local gas injection on coupling conditions. It also includes the relevant PCS functional blocks and interfaces with the ICH system. All components are developed and integrated within the ITER PCS Simulation Platform (PCSSP). The models are designed to balance computational efficiency with sufficient fidelity to reproduce ICH specific dynamics and fault conditions relevant to the early ITER operational phase (SRO). Initial tests confirm that local gas injection controlled in real-time by the PCS can compensate for changes in the RF coupling resistance due to slow variations in the plasma position so that the requested ICH power can be maintained.