Magnetic self organization, MHD active control and confinement in RFX-mod

RFX-mod is a reversed field pinch (RFP) experiment equipped with a system that actively controls the magnetic boundary. In this paper we describe the results of a new control algorithm, the clean mode control (CMC), in which the aliasing of the sideband harmonics generated by the discrete saddle coils is corrected in real time. CMC operation leads to a smoother (i.e. more axisymmetric) boundary. Tearing modes rotate (up to 100 Hz) and partially unlock. Plasma–wall interaction diminishes due to a decrease of the non-axisymmetric shift of the plasma column. With the ameliorated boundary control, plasma current has been successfully increased to 1.5 MA, the highest for an RFP. In such regimes, the magnetic dynamics is dominated by the innermost resonant mode, the internal magnetic field gets close to a pure helix and confinement improves.

V. Toigo | Sergio Ortolani | A. Luchetta | C. Taliercio | Paolo Bettini | Gabriele Manduchi | Piergiorgio Sonato | Elena Gaio | L. Apolloni | Francesco Gnesotto | G. Malesani | Giuseppe Marchiori | R. Piovan | P. Zaccaria | Giuseppe Zollino | Tommaso Bolzonella | Anton Soppelsa | N. Pomaro | R. Pasqualotto | Andrea Murari | A. De Lorenzi | Fulvio Auriemma | Giuseppe Chitarin | Paolo Innocente | Simone Peruzzo | Italo Predebon | Maria Ester Puiatti | M. Valisa | Paolo Piovesan | M. Cavinato | Roberto Cavazzana | M. Spolaore | G. Rostagni | D. Marcuzzi | Oliviero Barana | Alberto Alfier | Gianluigi Serianni | Matteo Brombin | Luca Grando | B. Zaniol | L. Carraro | N. Vianello | L. Giudicotti | Paolo Zanca | L. Novello | L. Zanotto | A. Masiello | F. Milani | L. Marrelli | Piero Martin | S. Dal Bello | Emilio Martines | Gianluca Spizzo | David Terranova | V. Antoni | Marco Gobbin | A. Buffa | E. Gazza | S. Martini | E. Zilli | Federica Bonomo | Paolo Scarin | D. F. Escande | C. Taccon | A. Canton | Emanuele Spada | F. Milani | A. Murari | M. Cavinato | L. Giudicotti | E. Zilli | P. Sonato | E. Gaio | R. Piovan | R. Paccagnella | T. Bolzonella | G. Marchiori | A. Luchetta | G. Manduchi | L. Marrelli | P. Martin | A. Masiello | S. Ortolani | G. Spizzo | P. Zanca | P. Bettini | G. Chitarin | V. Toigo | V. Antoni | N. Pomaro | G. Gadani | M. Brombin | R. Cavazzana | M. Moresco | L. Carraro | M. Puiatti | N. Vianello | M. Zuin | Piero Martin | M. Agostini | S. Martini | M. Valisa | P. Scarin | M. Spolaore | E. Martines | P. Innocente | A. Canton | G. Serianni | D. Terranova | A. Alfier | R. Pasqualotto | F. Sattin | R. Lorenzini | P. Piovesan | D. Bonfiglio | F. Bonomo | S. Cappello | D. Escande | A. Fassina | P. Franz | M. Gobbin | L. Apolloni | F. Auriemma | O. Barana | A. Buffa | A. Lorenzi | E. Gazza | F. Gnesotto | L. Grando | S. Guo | D. Marcuzzi | L. Novello | S. Peruzzo | A. Pizzimenti | I. Predebon | G. Rostagni | E. Spada | A. Soppelsa | C. Taliercio | P. Zaccaria | B. Zaniol | L. Zanotto | S. D. Bello | A. Murari | Rita Lorenzini | Alessandro Fassina | Matteo Zuin | Susanna Cappello | F. Sattin | Matteo Agostini | C. Alessi | G. Malesani | C. Taccon | G. Zollino | P. Franz | M. Moresco | S. C. Guo | R. Paccagnella | D. Bonfiglio | G. Gadani | A. Pizzimenti | C. Alessi | S. Dal Bello | M. Agostini | P. Bettini | M. Puiatti | A. de Lorenzi | S. Guo

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