Real-time control of the q-profile in JET for steady state advanced tokamak operation

D. Moreau, F. Crisanti, X. Litaudon, D. Mazon, P. De Vries, R. Felton, E. Joffrin, L. Laborde, M. Lennholm, A. Murari, V. Pericoli-Ridolfini, M. Riva, Tuomas Tala, G. Tresset, L. Zabeo, K.D. Zastrow, JET-EFDA collaborators

    Research output: Contribution to journalArticleScientificpeer-review

    81 Citations (Scopus)

    Abstract

    In order to simultaneously control the current and pressure profiles in high performance tokamak plasmas with internal transport barriers (ITB), a multi-variable model-based technique has been proposed. New algorithms using a truncated singular value decomposition (TSVD) of a linearized model operator and retaining the distributed nature of the system have been implemented in the JET control system. Their simplest versions have been applied to the control of the current density profile in reversed shear plasmas using three heating and current drive actuators (neutral beam injection, ion cyclotron resonant frequency heating and lower hybrid current drive). Successful control of the safety factor profile has been achieved in the quasi-steady-state, on a timescale of the order of the current redistribution time. How the TSVD algorithm will be used in the forthcoming campaigns for the simultaneous control of the current profile and of the ITB temperature gradient is discussed in some detail, but this has not yet been attempted in the present pioneering experiments.
    Original languageEnglish
    Pages (from-to)870-882
    JournalNuclear Fusion
    Volume43
    Issue number9
    DOIs
    Publication statusPublished - 2003
    MoE publication typeA1 Journal article-refereed

    Fingerprint

    profiles
    decomposition
    safety factors
    heating
    quasi-steady states
    beam injection
    cyclotron frequency
    neutral beams
    retaining
    resonant frequencies
    temperature gradients
    actuators
    current density
    shear
    operators
    ions

    Keywords

    • JET
    • plasma
    • Tokamak
    • fusion energy
    • fusion reactors
    • algorithms
    • internal transport barriers

    Cite this

    Moreau, D., Crisanti, F., Litaudon, X., Mazon, D., De Vries, P., Felton, R., ... JET-EFDA collaborators (2003). Real-time control of the q-profile in JET for steady state advanced tokamak operation. Nuclear Fusion, 43(9), 870-882. https://doi.org/10.1088/0029-5515/43/9/311
    Moreau, D. ; Crisanti, F. ; Litaudon, X. ; Mazon, D. ; De Vries, P. ; Felton, R. ; Joffrin, E. ; Laborde, L. ; Lennholm, M. ; Murari, A. ; Pericoli-Ridolfini, V. ; Riva, M. ; Tala, Tuomas ; Tresset, G. ; Zabeo, L. ; Zastrow, K.D. ; JET-EFDA collaborators. / Real-time control of the q-profile in JET for steady state advanced tokamak operation. In: Nuclear Fusion. 2003 ; Vol. 43, No. 9. pp. 870-882.
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    abstract = "In order to simultaneously control the current and pressure profiles in high performance tokamak plasmas with internal transport barriers (ITB), a multi-variable model-based technique has been proposed. New algorithms using a truncated singular value decomposition (TSVD) of a linearized model operator and retaining the distributed nature of the system have been implemented in the JET control system. Their simplest versions have been applied to the control of the current density profile in reversed shear plasmas using three heating and current drive actuators (neutral beam injection, ion cyclotron resonant frequency heating and lower hybrid current drive). Successful control of the safety factor profile has been achieved in the quasi-steady-state, on a timescale of the order of the current redistribution time. How the TSVD algorithm will be used in the forthcoming campaigns for the simultaneous control of the current profile and of the ITB temperature gradient is discussed in some detail, but this has not yet been attempted in the present pioneering experiments.",
    keywords = "JET, plasma, Tokamak, fusion energy, fusion reactors, algorithms, internal transport barriers",
    author = "D. Moreau and F. Crisanti and X. Litaudon and D. Mazon and {De Vries}, P. and R. Felton and E. Joffrin and L. Laborde and M. Lennholm and A. Murari and V. Pericoli-Ridolfini and M. Riva and Tuomas Tala and G. Tresset and L. Zabeo and K.D. Zastrow and {JET-EFDA collaborators}",
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    Moreau, D, Crisanti, F, Litaudon, X, Mazon, D, De Vries, P, Felton, R, Joffrin, E, Laborde, L, Lennholm, M, Murari, A, Pericoli-Ridolfini, V, Riva, M, Tala, T, Tresset, G, Zabeo, L, Zastrow, KD & JET-EFDA collaborators 2003, 'Real-time control of the q-profile in JET for steady state advanced tokamak operation', Nuclear Fusion, vol. 43, no. 9, pp. 870-882. https://doi.org/10.1088/0029-5515/43/9/311

    Real-time control of the q-profile in JET for steady state advanced tokamak operation. / Moreau, D.; Crisanti, F. ; Litaudon, X. ; Mazon, D. ; De Vries, P.; Felton, R. ; Joffrin, E.; Laborde, L.; Lennholm, M.; Murari, A.; Pericoli-Ridolfini, V. ; Riva, M.; Tala, Tuomas; Tresset, G.; Zabeo, L.; Zastrow, K.D.; JET-EFDA collaborators.

    In: Nuclear Fusion, Vol. 43, No. 9, 2003, p. 870-882.

    Research output: Contribution to journalArticleScientificpeer-review

    TY - JOUR

    T1 - Real-time control of the q-profile in JET for steady state advanced tokamak operation

    AU - Moreau, D.

    AU - Crisanti, F.

    AU - Litaudon, X.

    AU - Mazon, D.

    AU - De Vries, P.

    AU - Felton, R.

    AU - Joffrin, E.

    AU - Laborde, L.

    AU - Lennholm, M.

    AU - Murari, A.

    AU - Pericoli-Ridolfini, V.

    AU - Riva, M.

    AU - Tala, Tuomas

    AU - Tresset, G.

    AU - Zabeo, L.

    AU - Zastrow, K.D.

    AU - JET-EFDA collaborators

    PY - 2003

    Y1 - 2003

    N2 - In order to simultaneously control the current and pressure profiles in high performance tokamak plasmas with internal transport barriers (ITB), a multi-variable model-based technique has been proposed. New algorithms using a truncated singular value decomposition (TSVD) of a linearized model operator and retaining the distributed nature of the system have been implemented in the JET control system. Their simplest versions have been applied to the control of the current density profile in reversed shear plasmas using three heating and current drive actuators (neutral beam injection, ion cyclotron resonant frequency heating and lower hybrid current drive). Successful control of the safety factor profile has been achieved in the quasi-steady-state, on a timescale of the order of the current redistribution time. How the TSVD algorithm will be used in the forthcoming campaigns for the simultaneous control of the current profile and of the ITB temperature gradient is discussed in some detail, but this has not yet been attempted in the present pioneering experiments.

    AB - In order to simultaneously control the current and pressure profiles in high performance tokamak plasmas with internal transport barriers (ITB), a multi-variable model-based technique has been proposed. New algorithms using a truncated singular value decomposition (TSVD) of a linearized model operator and retaining the distributed nature of the system have been implemented in the JET control system. Their simplest versions have been applied to the control of the current density profile in reversed shear plasmas using three heating and current drive actuators (neutral beam injection, ion cyclotron resonant frequency heating and lower hybrid current drive). Successful control of the safety factor profile has been achieved in the quasi-steady-state, on a timescale of the order of the current redistribution time. How the TSVD algorithm will be used in the forthcoming campaigns for the simultaneous control of the current profile and of the ITB temperature gradient is discussed in some detail, but this has not yet been attempted in the present pioneering experiments.

    KW - JET

    KW - plasma

    KW - Tokamak

    KW - fusion energy

    KW - fusion reactors

    KW - algorithms

    KW - internal transport barriers

    U2 - 10.1088/0029-5515/43/9/311

    DO - 10.1088/0029-5515/43/9/311

    M3 - Article

    VL - 43

    SP - 870

    EP - 882

    JO - Nuclear Fusion

    JF - Nuclear Fusion

    SN - 0029-5515

    IS - 9

    ER -

    Moreau D, Crisanti F, Litaudon X, Mazon D, De Vries P, Felton R et al. Real-time control of the q-profile in JET for steady state advanced tokamak operation. Nuclear Fusion. 2003;43(9):870-882. https://doi.org/10.1088/0029-5515/43/9/311