Keyword: plasma
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MOPKS021 High-speed Data Handling Using Reflective Memory Thread for Tokamak Plasma Control controls, real-time, feedback, power-supply 203
  • S.Y. Park, S.H. Hahn, W.C. Kim
    NFRI, Daejon, Republic of Korea
  • R.D. Johnson, B.G. Penaflor, D.A. Piglowski, M.L. Walker
    GA, San Diego, California, USA
  The KSTAR plasma control system (PCS) is defined as a system consisting of electronic devices and control software that identifies and diagnoses various plasma parameters, calculates appropriate control signals to each actuator to keep the plasma sustained in the KSTAR operation regime. Based on the DIII-D PCS, the KSTAR PCS consists of a single box of multiprocess Linux system which can run up to 8 processes, and both digital and analog data acquisition methods are adapted for fast real-time data acquisition up to 20 kHz. The digital interface uses a well-known shared memory technology, the reflective memory (RFM), which can support data transmission up to 2Gbits/s. An RFM technology is adopted for interfacing the actuators, 11 PF power supplies and 1 IVC power supply, and the data acquisition system for plasma diagnostics. To handle the fast control of the RFM data transfer, the communication using the RFM with the actuators and diagnostics system is implemented as thread. The RFM thread sends commands like target current or voltage which is calculated by the PCS to the actuators area of RFM for plasma control and receives measured data by the magnet power supply. The RFM thread also provides the method for monitoring signal in real time by sharing data of diagnostics system. The RFM thread complete all data transfer within 50us so that data process can be completed within the fastest control cycle time of the PCS. This paper will describe the design, implementations, performances of RFM thread and applications to the tokamak plasma controls utilizing the technique.  
poster icon Poster MOPKS021 [1.745 MB]  
MOPMU035 Shape Controller Upgrades for the JET ITER-like Wall controls, real-time, operation, experiment 514
  • A. Neto, D. Alves, I.S. Carvalho
    IPFN, Lisbon, Portugal
  • G. De Tommasi, F. Maviglia
    CREATE, Napoli, Italy
  • R.C. Felton, P. McCullen
    EFDA-JET, Abingdon, Oxon, United Kingdom
  • P.J. Lomas, F. G. Rimini, A.V. Stephen, K-D. Zastrow
    CCFE, Culham, Abingdon, Oxon, United Kingdom
  • R. Vitelli
    Università di Roma II Tor Vergata, Roma, Italy
  Funding: This work was supported by the European Communities under the contract of Association between EURATOM/IST and was carried out within the framework of the European Fusion Development Agreement.
The upgrade of JET to a new all-metal wall will pose a set of new challenges regarding machine operation and protection. One of the key problems is that the present way of terminating a pulse, upon the detection of a problem, is limited to a predefined set of global responses, tailored to maximise the likelihood of a safe plasma landing. With the new wall, these might conflict with the requirement of avoiding localised heat fluxes in the wall components. As a consequence, the new system will be capable of dynamically adapting its response behaviour, according to the experimental conditions at the time of the stop request and during the termination itself. Also in the context of the new ITER-like wall, two further upgrades were designed to be implemented in the shape controller architecture. The first will allow safer operation of the machine and consists of a power-supply current limit avoidance scheme, which provides a trade-off between the desired plasma shape and the current distribution between the relevant actuators. The second is aimed at an optimised operation of the machine, enabling an earlier formation of a special magnetic configuration where the last plasma closed flux surface is not defined by a physical limiter. The upgraded shape controller system, besides providing the new functionality, is expected to continue to provide the first line of defence against erroneous plasma position and current requests. This paper presents the required architectural changes to the JET plasma shape controller system.
poster icon Poster MOPMU035 [2.518 MB]  
TUBAUST01 FPGA-based Hardware Instrumentation Development on MAST FPGA, controls, hardware, diagnostics 544
  • B.K. Huang, R.M. Myers, R.M. Sharples
    Durham University, Durham, United Kingdom
  • N. Ben Ayed, G. Cunningham, A. Field, S. Khilar, G.A. Naylor
    CCFE, Abingdon, Oxon, United Kingdom
  • R.G.L. Vann
    York University, Heslington, York, United Kingdom
  Funding: This work was part-funded by the RCUK Energy Programme under grant EP/I501045 and the European Communities under the Contract of Association between EURATOM and CCFE.
On MAST (the Mega Amp Spherical Tokamak) at Culham Centre for Fusion Energy some key control systems and diagnostics are being developed and upgraded with FPGA hardware. FPGAs provide many benefits including low latency and real-time digital signal processing. FPGAs blur the line between hardware and software. They are programmed (in VHDL/Verilog language) using software, but once configured act deterministically as hardware. The challenges in developing a system are keeping up-front and maintenance costs low, and prolonging the life of the device as much as possible. We accomplish lower costs by using industry standards such as the FMC (FPGA Mezzanine Card) Vita 57 standard and by using COTS (Commercial Off The Shelf) components which are significantly less costly than developing them in-house. We extend the device operational lifetime by using a flexible FPGA architecture and industry standard interfaces. We discuss the implementation of FPGA control on two specific systems on MAST. The Vertical Stabilisation system comprises of a 1U form factor box with 1 SP601 Spartan6 FPGA board, 10/100 Ethernet access, Microblaze processor, 24-bit σ delta ADS1672 ADC and ATX power supply for remote power cycling. The Electron Bernstein Wave system comprises of a 4U form factor box with 2 ML605 Virtex6 FPGA boards, Gigabit Ethernet, Microblaze processor and 2 FMC108 ADC providing 16 Channels with 14-bit at 250MHz. AXI4 is used as the on chip bus between firmware components to allow very high data rates which has been tested at over 40Gbps streaming into a 2GB DDR3 SODIMM.
slides icon Slides TUBAUST01 [8.172 MB]  
TUCAUST05 New Development of EPICS-based Data Acquisition System for Millimeter-wave Interferometer in KSTAR Tokamak diagnostics, data-acquisition, operation, EPICS 577
  • T.G. Lee, Y.U. Nam, M.K. Park
    NFRI, Daejon, Republic of Korea
  After achievement of first plasma in 2008, Korea Superconducting Tokamak Advanced Research (KSTAR) is going to be performed in the 4nd campaign in 2011. During the campaigns, many diagnostic devices have been installed for measuring the various plasma properties in the KSTAR tokamak. From the first campaign, a data acquisition system of Millimeter-wave interferometer (MMWI) has been operated to measure the plasma electron density. The DAQ system at the beginning was developed for three different diagnostics having similar channel characteristics with a VME-form factor housing three digitizers in Linux OS platform; MMWI, H-alpha and ECE radiometer. However, this configuration made some limitations in operation although it had an advantage in hardware utilization. It caused unnecessarily increasing data acquired from the other diagnostics when one of them operated at higher frequency. Moreover, faults in a digitizer led to failure in data acquisition of the other diagnostics. In order to overcome these weak points, a new MMWI DAQ system is under development with a PXI-form factor in Linux OS platform and main control application is going to be developed based on EPICS framework like other control systems installed in KSTAR. It also includes MDSplus interface for the pulse-based archiving of experimental data. Main advantages of the new MMWI DAQ system besides solving the described problems are capabilities of calculating plasma electron density during plasma shot and display it in run-time. By this the data can be provided to users immediately after archiving in MDSplus DB.  
slides icon Slides TUCAUST05 [1.724 MB]  
WEPMN014 The Software and Hardware Architectural Design of the Vessel Thermal Map Real-Time System in JET real-time, Linux, controls, network 905
  • D. Alves, A. Neto, D.F. Valcárcel
    IPFN, Lisbon, Portugal
  • G. Arnoux, P. Card, S. Devaux, R.C. Felton, A. Goodyear, D. Kinna, P.J. Lomas, P. McCullen, A.V. Stephen, K-D. Zastrow
    CCFE, Abingdon, Oxon, United Kingdom
  • S. Jachmich
    RMA, Brussels, Belgium
  The installation of ITER-relevant materials for the plasma facing components (PFCs) in the Joint European Torus (JET) is expected to have a strong impact on the operation and protection of the experiment. In particular, the use of all-beryllium tiles, which deteriorate at a substantially lower temperature than the formerly installed CFC tiles, imposes strict thermal restrictions on the PFCs during operation. Prompt and precise responses are therefore required whenever anomalous temperatures are detected. The new Vessel Thermal Map (VTM) real-time application collects the temperature measurements provided by dedicated pyrometers and Infra-Red (IR) cameras, groups them according to spatial location and probable offending heat source and raises alarms that will trigger appropriate protective responses. In the context of JET's global scheme for the protection of the new wall, the system is required to run on a 10 millisecond cycle communicating with other systems through the Real-Time Data Network (RTDN). In order to meet these requirements a Commercial Off-The-Shelf (COTS) solution has been adopted based on standard x86 multi-core technology, Linux and the Multi-threaded Application Real-Time executor (MARTe) software framework. This paper presents an overview of the system with particular technical focus on the configuration of its real-time capability and the benefits of the modular development approach and advanced tools provided by the MARTe framework.
See the Appendix of F. Romanelli et al., Proceedings of the 23rd IAEA Fusion Energy Conference 2010, Daejeon, Korea
poster icon Poster WEPMN014 [5.306 MB]  
WEPMU018 Real-time Protection of the "ITER-like Wall at JET" real-time, FPGA, controls, network 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. controls, real-time, diagnostics, operation 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]