Review of the Innovative H and CD Designs and the Impact of Their Configurations on the Performance of the EU DEMO Fusion Power Plant Reactor

Heating and current drive (H and CD) systems are being investigated for a demonstration fusion power plant DEMO to deliver net electricity for the grid around 2050. Compared to ITER, which has to show the generation of 500-MW thermal power, the target of DEMO is the successful production of 300 to 500 MW electrical power to the grid and to aim for a self-sufficient tritium fuel cycle. Three H and CD systems are under development for DEMO in Europe, the electron cyclotron (EC) system, the neutral beam injection (NBI) system, and the ion cyclotron system. Based on present studies for plasma ramp-up, ramp-down, and flat top phases, to be further validated in more detailed simulations, the assumed total launched power needed from the H and CD system in DEMO is in the range of 50-100 MW, to be provided for plasma heating and control. This paper describes the design and Research and Development status of selected H and CD systems, considered for their deployment in the EU DEMO. It was always considered that different H and CD configurations and design variants will have an impact on the performances for the whole fusion plant. It shall be noted that the basis for the H and CD integrated design and system development is the actual version of the European fusion electricity roadmap. The project also elaborates on H and CD efficiency improvements which will reduce the recirculating power fraction in the future fusion power plants. Different studies under investigation will be discussed such as for NBI the photo-neutralization and for EC novel concepts for gyrotron multistage-depressed collector. (authors)