Author: D.J. WardPublisher:
ISBN:
Category :
Languages : en
Pages : 21
Book Description
Active Feedback Stabilization of Axisymmetric Modes in Highly Elongated Tokamak Plasmas
Author: D.J. WardFeedback Stabilization of Axisymmetric Modes in Tokamaks
Author: Publisher:
ISBN:
Category :
Languages : en
Pages :
Book Description
Noncircular tokamak plasmas can be unstable to ideal MHD axisymmetric instabilities. Passive conductors with finite resistivity will at best slow down these instabilities to the resistive (L/R) time of the conductors. An active feedback system far from the plasma which responds on this resistive time can stabilize the system provided its mutual inductance with the passive coils is small enough.
The Effects of Plasma Deformability on the Feedback Stabilization of Axisymmetric Modes in Tokamak Plasmas
Author: Publisher:
ISBN:
Category :
Languages : en
Pages : 55
Book Description
The effects of plasma deformability on the feedback stabilization of axisymmetric modes of tokamak plasmas are studied. It is seen that plasmas with strongly shaped cross sections have unstable motion different from a rigid shift. Furthermore, the placement of passive conductors is shown to modify the non-rigid components of the eigenfunction in a way that reduces the stabilizing eddy currents in these conductors. Passive feedback results using several equilibria of varying shape are presented. The eigenfunction is also modified under the effects of active feedback. This deformation is seen to depend strongly on the position of the flux loops which are used to determine plasma vertical position for the active feedback system. The variations of these non-rigid components of the eigenfunction always serve to reduce the stabilizing effect of the active feedback system by reducing the measurable poloidal flux at the flux-loop locations. Active feedback results are presented for the PBX-M tokamak configuration.
Studies of Feedback Stabilization of Axisymmetric Modes in Deformable Tokamak Plasmas
Author: David John WardThe Effects of Plasma Deformability on the Feedback Stabilization of Axisymmetric Modes in Tokamak Plasmas
Author: Publisher:
ISBN:
Category :
Languages : en
Pages : 55
Book Description
The effects of plasma deformability on the feedback stabilization of axisymmetric modes of tokamak plasmas are studied. It is seen that plasmas with strongly shaped cross sections have unstable motion different from a rigid shift. Furthermore, the placement of passive conductors is shown to modify the non-rigid components of the eigenfunction in a way that reduces the stabilizing eddy currents in these conductors. Passive feedback results using several equilibria of varying shape are presented. The eigenfunction is also modified under the effects of active feedback. This deformation is seen to depend strongly on the position of the flux loops which are used to determine plasma vertical position for the active feedback system. The variations of these non-rigid components of the eigenfunction always serve to reduce the stabilizing effect of the active feedback system by reducing the measurable poloidal flux at the flux-loop locations. Active feedback results are presented for the PBX-M tokamak configuration.
Feedback Stabilization of Axisymmetric Modes in Tokamaks
Author: S. C. JardinEnergy Research Abstracts
Author: Feedback Stabilization of Axisymmetric Modes in the TCV Tokamak Using Active Coils Inside and Outside the Vacuum Vessel
Author: Magnetic Control of Tokamak Plasmas
Author: Marco AriolaPublisher: Springer
ISBN: 3319298909
Category : Technology & Engineering
Languages : en
Pages : 208
Book Description
This book is a complete treatment of work done to resolve the problems of position-, current-, and shape-control of plasma in tokamak-type (toroidal) devices being studied as a potential means of commercial energy production by nuclear fusion. Modelling and control are both detailed, allowing non-expert readers to understand the control problem. Starting from the magneto-hydro-dynamic equations, all the steps needed for the derivation of plasma state-space models are enumerated with frequent recall of the basic concepts of electromagnetics. The control problem is then described, beginning with the control of current and position—vertical and radial—control and progressing to the more challenging shape control. The solutions proposed vary from simple PIDs to more sophisticated MIMO controllers. The second edition of Magnetic Control of Tokamak Plasmas contains numerous updates and a substantial amount of completely new material covering areas such as: • modelling and control of resistive wall modes—the most important non-axisimmetric mode; • the isoflux approach for shape control; • a general approach for the control of limiter plasmas; • the use of inner vessel coils for vertical stabilization; and • significantly enhanced treatment of plasma-shape control at JET, including experimental results and introducing a method implemented for operation in the presence of current saturations. Whenever possible, coverage of the various topics is rounded out with experimental results obtained on currently existing tokamaks. The book also includes a presentation of the typical actuators and sensors used for control purposes in tokamaks. Some mathematical details are given in the appendices for the interested reader. The ideas formulated in this monograph will be of great practical help to control engineers, academic researchers and graduate students working directly with problems related to the control of nuclear fusion. They will also stimulate control researchers interested more generally in the advanced applications of the discipline. Advances in Industrial Control aims to report and encourage the transfer of technology in control engineering. The rapid development of control technology has an impact on all areas of the control discipline. The series offers an opportunity for researchers to present an extended exposition of new work in all aspects of industrial control.
TSC Simulation of Feedback Stabilization of Axisymmetric Modes in Tokamaks Using Driven Halo Currents
Author: S. C. JardinPublisher:
ISBN:
Category : Tokamaks
Languages : en
Pages : 21
Book Description