Report on the operation and control of the fusion DEMO reactors

This is the final report under the NIFS Joint Research Program concerning one of the important theme 'System Analysis on Operation and Control of the Fusion DEMO Power Plant'. Joint studies have been made in the past three years through four symposiums focusing on the critical subjects. This report was written after these symposiums reflecting the most critical subjects that should be stressed and initiated at this phase of the fusion development. There have been a lot of meetings and symposiums on DEMO related topics, but little documents have been made on a common view of researchers. Therefore, similar discussion took place and repeated when the generation changed. For this reason, this activity started with 'a declaration of issuing final agreed report at the end of the activities'. The report deals with possible actuators for the operation and control of steady state DEMO reactor, and clarified the importance of the inward plasma transport that determines the fusion output. Systematic study of plasma and neutral particle transports of DT and He initiating from the fueling and ending to the vacuum pumping further illuminates the importance of DT neutrals as hidden parameter from the view point of reactor operation and control. (author)