Author: Thomas, P.D.
Paper Title Page
WEPMU018 Real-time Protection of the "ITER-like Wall at JET" 1096
  • M.B. Jouve, C. Balorin
    Association EURATOM-CEA, St Paul Lez Durance, France
  • G. Arnoux, S. Devaux, D. Kinna, P.D. Thomas, K-D. Zastrow
    CCFE, Abingdon, Oxon, United Kingdom
  • P.J. Carvalho
    IPFN, Lisbon, Portugal
  • J. Veyret
    Sundance France, Matignon, France
  During the last JET tokamak shutdown a new ITER-Like Wall was installed using Tungsten and Beryllium materials. To ensure plasma facing component (PFC) integrity, the real-time protection of the wall has been upgraded through the project "Protection for the ITER-like Wall" (PIW). The choice has been made to work with 13 CCD robust analog cameras viewing the main areas of plasma wall interaction and to use regions of interest (ROI) for monitoring in real time the surface temperature of the PFCs. For each camera, ROIs will be set up pre-pulse and, during plasma operation, surface temperatures from these ROIs will be sent to the real time processing system for monitoring and eventually preventing damages on PFCs by modifying the plasma parameters. The video and the associated control system developed for this project is presented in this paper. The video is captured using PLEORA frame grabber and it is sent on GigE network to the real time processing system (RTPS) divided into a 'Real time processing unit' (RTPU), for surface temperature calculation, and the 'RTPU Host', for connection between RTPU and other systems. The RTPU design is based on commercial Xilinx Virtex5 FPGA boards with one board per camera and 2 boards per host. Programmed under Simulink using System generator blockset, the field programmable gate array (FPGA) can manage simultaneously up to 96 ROI defined pixel by pixel.  
poster icon Poster WEPMU018 [2.450 MB]  
FRAAULT04 Centralised Coordinated Control to Protect the JET ITER-like Wall. 1293
  • A.V. Stephen, G. Arnoux, T. Budd, P. Card, R.C. Felton, A. Goodyear, J. Harling, D. Kinna, P.J. Lomas, P. McCullen, P.D. Thomas, I.D. Young, K-D. Zastrow
    CCFE, Abingdon, Oxon, United Kingdom
  • D. Alves, D.F. Valcárcel
    IST, Lisboa, Portugal
  • S. Devaux
    MPI/IPP, Garching, Germany
  • S. Jachmich
    RMA, Brussels, Belgium
  • A. Neto
    IPFN, Lisbon, Portugal
  Funding: This work was carried out within the framework of the European Fusion Development Agreement. This work was also part-funded by the RCUK Energy Programme under grant EP/I501045.
The JET ITER-like wall project replaces the first wall carbon fibre composite tiles with beryllium and tungsten tiles which should have improved fuel retention characteristics but are less thermally robust. An enhanced protection system using new control and diagnostic systems has been designed which can modify the pre-planned experimental control to protect the new wall. Key design challenges were to extend the Level-1 supervisory control system to allow configurable responses to thermal problems to be defined without introducing excessive complexity, and to integrate the new functionality with existing control and protection systems efficiently and reliably. Alarms are generated by the vessel thermal map (VTM) system if infra-red camera measurements of tile temperatures are too high and by the plasma wall load system (WALLS) if component power limits are exceeded. The design introduces two new concepts: local protection, which inhibits individual heating components but allows the discharge to proceed, and stop responses, which allow highly configurable early termination of the pulse in the safest way for the plasma conditions and type of alarm. These are implemented via the new real-time protection system (RTPS), a centralised controller which responds to the VTM and WALLS alarms by providing override commands to the plasma shape, current, density and heating controllers. This paper describes the design and implementation of the RTPS system which is built with the Multithreaded Application Real-Time executor (MARTe) and will present results from initial operations.
slides icon Slides FRAAULT04 [2.276 MB]