1. Magnets
Magnet technology for magnetic confinement fusion has advanced to the point where several tokamaks and stellarators are now operating with superconducting magnets. The construction of ITER is taking the technology of fusion magnets based on low-temperature superconducting (LTS) magnets to an unprecedented scale. Already, high-temperature superconductors (HTS) are being considered for use in next-step fusion devices. This session will focus on the possibilities for further advances in magnet technology, including but not limited to HTS, which can benefit the fusion programme. Comparisons with present technology will include design implications and limitations, manufacturing capability and capacity, economics, and safety implications.
2. Control of DEMO Plasmas
Previous DEMO Programme Workshop (DPW) reviews of plasma scenarios and their control requirements have stressed the need for robust control close to operational boundaries. Control in DEMO will have to ensure maximum availability at the chosen operating point, so it will potentially be quite different from present day devices which place greater emphasis on flexibility. The DPW 5 session on plasma control will include: (i) a review of advanced control techniques, focusing on associated requirements for sensors and actuators; and (ii) plasma scenario requirements compatible with the limitations of diagnostics and actuators under DEMO conditions. The advanced control techniques will include nonlinear controllers and state-observers. Model-based versus empirical approaches will be compared. Special emphasis will be placed on minimizing the disruptivity and identifying gaps and strategies to cope with unpredictable or rapid events. These subjects are of great importance for ITER as well, and hence a strong link to the developments for ITER in this field will be made.
3. Remote Maintenance and Plant Logistics
The remote maintenance (RM) requirements of DEMO operation are major drivers of component design and machine configuration and operation. Ensuring compatibility with access and manoeuvring requirements whilst simultaneously satisfying safety constraints will significantly impact the design of the entire facility with considerable bearing on cost. This session will include comparison of different RM schemes (e.g. vertical and horizontal), limitations that impact design (e.g. lift weight), operations in high radiation environments (e.g. sensors, virtual modelling), hot cell requirements, virtual engineering and scaled prototyping.
4. Special Topics
• Integrated Assessment of Liquid Metals as Plasma Facing Components on the First Wall and Divertor – Charles KESSEL, Princeton Plasma Physics Laboratory;
• K-DEMO Status and Progress – Keeman KIM, Director General, National Fusion Research Institute;
• JT60 – SA, Status and Scientific Objectives – Akira SAKASAI, Deputy Japanese Project Manager of the JT-60SA.
