ITER TF model coil assembly, commissioning and instrumentation

Abstract

The International thermonuclear experimental reactor (ITER) toroidal field model coil (TFMC) and its associated intercoil structure (ICS) will be tested in two phases in the TOSKA facility, alone in phase one, adjacent to the euratom large coil task (EU-LCT) coil in phase 2. Both the TFMC and ICS are large components that normally do not fit into available testing facilities. A programme of pressure and leak testing has been developed which gives confidence that these components fulfil the stringent manufacturing requirements. As a first step the TFMC/ICS will be tested as a single coil. Thus all main parts of the test arrangement which have not yet undergone a cryogenic testing will be checked before any high magnetic fields and electromagnetic forces will be applied. The whole load of the coil assembly will rest on three support points within the TOSKA vessel. The build up of all geometric tolerances must be maintained to allow good alignment of the various electrical and hydraulic connections. Specific attention is paid to the procedure of installation of TFMC, ICS adjacent to the EU-LCT coil. The overall dimensions of the coil case and the ICS is continuously checked as well. Instrumentation of the coil includes voltage taps, high sensitivity temperature sensors, strain gauges, rosettes, displacement transducers, flow rate and pressure drop sensors and magnetic field sensors. In particular, the induced mechanical deformation of the coil by the electromagnetic force are monitored by strain gauges and strain gauge rosettes positioned along the main axes of the case and at the most highly stressed wedges of the ICS. Displacement sensors monitor the allowable elongation of the joint area connecting adjacent double pancakes of the winding.