Semi-emprical techniques for the specification of Shafranov shift in the large aspect ratio tokamaks

摘要

Equilibrium reconstruction consists in identifying, from experimental measurements, a distribution of the plasma current density that satisfies the pressure balance constraint. Numerous methods exist to solve the Grad-Shafranov equation, describing the equilibrium of plasma confined by an axisymmetric magnetic field. In this research, we have reviewed six techniques for determination of the plasma position in IR-T1 tokamak and the effects of superconducting coils and chamber: an optical, flux loops, magnetic probes, multipole moments techniques, and two methods based on the vertical field coil characteristics and analytical solution of Grad-Shafranov equation. In the first method an image processing technique used for the output signal of CCD camera and plasma emission intensity profile and then plasma position obtained. To compare the plasma position obtained using this method, flux loop method, magnetic probe method, multipole moments method, analytical solution of Grad-Shafranov equation, and a sensor-less method based on vertical field coil characteristics are also experimented on the IR-T1 tokamak. Results were compared and discussed. (C) 2016 Hydrogen Energy Publications LLC. Published by Elsevier Ltd. All rights reserved.