A. Encheva

The magnetic diagnostic set for ITER

This paper presents the multiple set of requirements for the ITER magnetic diagnostic systems and the current status of the various R&D activities performed by the EU partners.

ITER diagnostic challenges

ITER will explore a plasma parameter envelope currently not available in tokamaks. This will require a set of diagnostics that can follow this envelope. To implement these diagnostics in a reliable and robust way requires development of current techniques in many areas to make them applicable to ITER: they need to be operable in the ITER environment and satisfy the physics and engineering requirements. In some cases, the exploitation of new techniques will be required. While much work has been carried out in this area, significant further work remains to bring the system to implementation.

Design and manufacture of the ITER Vacuum Vessel

The main functions of the ITER Vacuum Vessel (VV) are to provide the necessary vacuum for plasma operation, act as first nuclear confinement barrier and remove nuclear heating. The design of the VV has been reviewed in the past two years due to more advanced analyses, design modifications required by the interfacing components and R&D. Following the signature of four Procurement Arrangement (PAs), the manufacturing design of the VV sectors, ports and In-Wall Shielding (IWS) is being finalized and the fabrication of the VV sectors has been started in 2012.

Baseline system design and prototyping for the ITER high-frequency magnetic diagnostics set

This paper reports the mechanical and electrical tests performed for the prototyping of the ITER high-frequency magnetic sensor and the analysis of the measurement performance of this diagnostic. The current design for the sensor is not suitable for manufacturing for ITER due to the high likelihood of breakages of the un-guided tungsten wire during the winding. A number of alternative designs and manufacturing processes have been investigated, with the Low Temperature Co-fired Ceramic technology giving the best results. The measurement performance of the baseline system design for the high-frequency magnetic diagnostic cannot meet the intended ITER requirements due to its intrinsic spatial periodicities.

Brackets Without Welding for ITER ELM Coils

A nonwelded bracket design is proposed and evaluated for the ITER edge localized mode coil fixture on the vacuum vessel. The main benefits are a lower stress concentration under thermal load, a broad choice of higher strength material, and assembly flexibility. Concerns about possible excessive temperatures are assessed and verified. The bracket is shown under 500 °C with a steady-state full-powered plasma operation.

New design options for ITER ELM coil brackets

A non-welded bracket design is proposed and evaluated for the ITER ELM Coil fixture on the Vacuum Vessel. The main benefits include a lower stress concentration, a broad choice of higher strength material and assembly flexibility. Possible excessive temperatures are assessed and verified. The bracket is shown under 500C with steady-state full powered plasma operation, which is a very conservative case. Further detailed design is under consideration to put pre-stress on the brackets.

Assembly and installation of ITER in-vessel electrical looms

This paper outlines the assembly and installation strategy of ITER in-vessel electrical looms. It will focus as well on the design of the looms, and the major requirements from integration and assembly point of view.