학술논문

Plasma position measurements by O-mode and X-mode reflectometry systems in tokamak plasmas.
Document Type
Article
Source
Review of Scientific Instruments. Jun2023, Vol. 94 Issue 6, p1-10. 10p.
Subject
*FUSION reactors
*REFLECTOMETRY
*TOKAMAKS
*PHASE shift (Nuclear physics)
*REAL-time control
*MAGNETIC measurements
*REFLECTOMETER
Language
ISSN
0034-6748
Abstract
Plasma Position Reflectometry (PPR) is planned to provide plasma position and shape information for plasma operation in future fusion reactors. Its primary function is to calibrate the drift of the magnetic signals due to the integral nature of magnetic measurement. Here, we attempt to measure plasma position using ordinary mode (O-mode) and extraordinary mode (X-mode) reflectometry systems on two tokamaks. A new physical model based on the phase shift is proposed to deduce the relative movement of the cut-off layer without density inversion. We demonstrate the plasma position measurements by absolute measurement from density profile inversion and relative measurement from phase shift. The combination of X-mode and O-mode reflectometers can minimize the limitations of single polarization reflectometry and further increase the accuracy of plasma position measurement. These results could provide an important technical basis for the further development of a real-time control system based on PPR. [ABSTRACT FROM AUTHOR]