Active Feedback Control of Kink Modes in Tokamaks: 3D VALEN Modeling and HBT-EP Experiments*
نویسندگان
چکیده
Significant progress in the development of active feedback control as a robust technique for the suppression of the wall stabilized external kink or resistive wall mode (RWM) in tokamaks has been achieved through a combination of modeling and experiments. Results from the application and benchmarking of the 3D feedback modeling code VALEN [1] as the primary analysis and feedback design tool on the HBT-EP [2] and DIII-D [3] experiments are in good agreement with observations, and modeling of proposed advanced control system designs on HBT-EP, DIII-D, NSTX [4], FIRE [5], and ITER are predicted to approach the ideal wall beta limit in agreement with design principles based on the simple single mode analytic theory of RWM feedback control [6]. Benchmark experiments on HBT-EP have shown suppression of disruptions at rational edge q values using active “smart shell” feedback control, the initiation of the first test of directly coupled coils designed to operate up to the ideal wall limit on RWM behavior, as well as observation of the plasma amplification of static resonant magnetic fields in plasmas marginally stable to the RWM in agreement with theory [7].
منابع مشابه
Modeling of active control of external magnetohydrodynamic instabilities
A general circuit formulation of resistive wall mode ~RWM! feedback stabilization developed by Boozer @Phys. Plasmas 5, 3350 ~1998!# has been used as the basis for the VALEN computer code that calculates the performance of an active control system in arbitrary geometry. The code uses a finite element representation of a thin shell structure in an integral formulation to model arbitrary conducti...
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