Progress in the ITER electron cyclotron heating and current drive system design

Omori, Toshimichi*; Albajar, F.*; Bonicelli, T.*; Darbos, C.*; Denisov, G.*; Gassmanna, T.*; Hanson, G.*; Kajiwara, Ken; Oda, Yasuhisa; Purohit, D.*; Rao, S. L.*; Rasmussen, D.*; Rathod, V.*; Saibene, G.*; Sakamoto, Keishi; Singh, N. P.*; Takahashi, Koji; 18 of others*

An electron cyclotron (EC) system is one of four auxiliary plasma heating systems to be installed in ITER tokamak. The ITER EC system consists of 24 gyrotrons (RFPS: RF power source) with associated 12 high voltage power supplies (HVPSs), a set of evacuated transmission lines (TLs) and two types of launchers. The whole system is designed compatible with propagation of 170 GHz of up to 20 MW microwave power into the plasma. The primary functions of the system include plasma start-up, central heating and current drive (H&CD) and magneto-hydrodynamic (MHD) instabilities control. The design takes present day technology and extends toward high power CW operation, which represents a large step forward as compared to the present state of the art. The ITER EC system will be a stepping stone to future EC systems for DEMO and beyond. The EC system is faced with significant challenges, which not only includes an advanced microwave system for plasma heating and current drive applications but also has to comply with stringent requirements associated with nuclear safety as ITER became the first fusion device licensed as basic nuclear installations as of 9 November 2012. Since conceptual design of the EC system established in 2007, the EC system has progressed to a preliminary design stage in 2012, and is now moving forward toward a final design. The majority of the subsystems are getting to knuckle down the detailed design to realize the future advancement envisioned toward the final design completion.