Plasma flux expansion control on the DIII-D tokamak. (13th November 2020)

• Record Type: Journal Article
• Authors: Anand, H; Humphreys, D; Eldon, D; Leonard, A; Hyatt, A; Sammuli, B; Welander, A
• Is Part Of: Plasma physics and controlled fusion. Volume 63:Number 1(2021)
• Publication Date: 2020-11-13
• Subjects: real-time control -- magnetic control -- scrape-off layer -- flux expansion -- magnetic equilibrium reconstruction.; Plasma (Ionized gases) -- Periodicals; Controlled fusion -- Periodicals; 530.44
• DOI: 10.1088/1361-6587/abc457
• Languages: English
• ISSNs: 0741-3335

Abstract

Abstract: A new controller has been developed with help of the flexible divertor poloidal-field coil set of the DIII-D tokamak, to aid in the precise control of the flux expansion in the scrape-off layer. The single-input multiple-output architecture ensures flexibility through a complementary set of orthogonal actuator direction to guarantee minimum effect on existing controlled variables, e.g. radial and vertical position control of the X-point. A non-linear free-boundary simulation code (GSevolve) is used for simulating the closed-loop response and for verifying the implementation of the control algorithm on the DIII-D plasma control system. First results of the experimental commissioning of the new controller during 2020 DIII-D campaign are also presented.