Abstract
Institute for Plasma Research (IPR) is developing Spherical Tokamak (ST) related technologies to realize a low aspect ratio compact device for plasma experiments. Center Stack is one of the critical components in ST which requires R&D to design, manufacture and assemble in a limited space within required tolerances. A Prototype Center Stack (PCS) is being developed based on reference ST parameters with major radius 0.28 m and minor radius 0.16 m for magnetic field 0.1 T. The main objective of PCS is to design and check its manufacturing feasibility to achieve required tolerances at component and assembly level and maintaining overall accuracy. The PCS assembly consists of two sets of coils, namely Toroidal Field (TF) coils and Ohmic (OH) coil made of Electrolytic Tough Pitch (ETP) Copper. It consists of 6 number of TF coils, with 3 turns per coil, all connected in series. The OH coil has two parallel layers, with 143 turns per layer. The SS 304 support structure consists of tension cylinder and Center Stack Casing (CSC) which are mounted on a pedestal support. Two different capacitor bank based power supplies are considered for TF and OH coils with a maximum operating current of 8.5 kA and 10 kA respectively. This paper discusses the conceptual design, engineering analysis including thermal, electromagnetic and structural analysis using ANSYS Mechanical, Multiphysics and Maxwell modules.
