ITER IC H&CD system: physics requirements and performance predictions

The ITER Ion Cyclotron Heating and Current Drive (IC H&CD) system will deliver 20MW of radio frequency power to the plasma in quasi continuous operation during the different phases of the experimental programme. It must have a high availability and reliably couple to ELMy H-Mode plasmas. It has the additional functionality of performing wall conditioning (ICWC) at powers up to ˜3MW. The paper will 1) discuss the physics and design requirements on the system, 2) review the main scenarios planned for H&CD and ICWC, 3) describe the main features of the current design, 4) discuss performance predictions based on recent modelling, and 5) present the key measures under implementation to reduce risks on performanc

ITER IC H&CD system: physics requirements and performance predictions

The ITER Ion Cyclotron Heating and Current Drive (IC H&CD) system will deliver 20MW of radio frequency power to the plasma in quasi continuous operation during the different phases of the experimental programme. It must have a high availability and reliably couple to ELMy H-Mode plasmas. It has the additional functionality of performing wall conditioning (ICWC) at powers up to ˜3MW. The paper will 1) discuss the physics and design requirements on the system, 2) review the main scenarios planned for H&CD and ICWC, 3) describe the main features of the current design, 4) discuss performance predictions based on recent modelling, and 5) present the key measures under implementation to reduce risks on performance

Modelling one-third field operation in the ITER pre-fusion power operation phase

In the four-stage approach of the new ITER Research Plan, the first pre-fusion power operation (PFPO) phase will only have limited power available from external heating and current drive (H&amp;CD) systems: 20-30 MW provided by the electron cyclotron resonance heating (ECRH) system. Accessing the H-mode confinement regime at such low auxiliary power requires operating at low magnetic field, plasma current and density, i.e. 1.8 T and 5 MA for a density between 40% and 50% of the Greenwald density. H-mode plasmas at 5 MA/1.8 T will also be investigated in the second PFPO phase when ITER will have its full complement of H&amp;CD capabilities installed, i.e. 20-30 MW of ECRH, 20 MW of ion cyclotron resonance heating and 33 MW of neutral beam injection. This paper describes the operational constraints and the H&amp;CD capabilities for such scenarios in hydrogen and helium plasmas, to assess their viability and the issues it will be possible to address with them. The modelling results show that 5 MA/1.8 T scenarios are viable and will allow the exploration of the H-mode physics and control issues foreseen in the ITER Research Programme in the PFPO phases.</p