ITER ECH&CD Transmission Line Layout Development

Abstract

A primary contributor to the effectiveness of the ITER electron cyclotron (EC) heating & current drive (H&CD) transmission line (TL) is the distortion of the waveguide which has a strong, direct correlation with power transmission efficiency and electromagnetic mode purity. Two main sources of distortion are the deflection of the TL due to operational loads and misalignment of the waveguide supports. To address these and other interdependent variables, the EC TL design focused on a holistic method to provide iterative simultaneous development of the system and microwave components. The process provided close, rapid interconnectivity between the prescribed subsystem requirements and the design activities being performed, including a detailed 3D configuration management model, a system structural finite element analysis, a thorough multi-sample Monte-Carlo system functional performance assessment, and individual microwave component designs & analyses. This paper intends to provide an overview of the first of these: the design development process of the TL layout. This includes investigating the inputs into layout optimization, the overall integration process, the interconnectivity with the other design activities, and their impacts on TL subsystem performance that ultimately resulted in the current baseline layout.