LLRF requirements for the JAEA-ADS linac

Yee-Rendon, B. ; Kondo, Yasuhiro   ; Tamura, Jun  ; Meigo, Shinichiro   ; Maekawa, Fujio  

The Japan Atomic Energy Agency (JAEA) is carrying out research and development on an Accelerator Driven Subcritical System (ADS) for nuclear transmutation. The JAEA-ADS consists of a CW superconducting proton linac of 30 MW coupling with a subcritical core reactor. The linac will accelerate a 20-mA proton beam to a final energy of 1.5 GeV, starting with a Normal Conducting section up to 2.5 MeV, and followed by a Superconducting part. More than 300 LLRF systems will control longitudinal parameters of the RF structures that compose the linac. In addition to ensuring stability on RF settings for efficient linac performance, the JAEA-ADS LLRF system will also enable fault-tolerance compensations to increase the availability of the linac, which is a major challenge for ADS operation. In this work, we will discuss the necessity of the ADS LLRF and present a proposed model that satisfies these demands.