학술논문

Investigation of Developed Liquid Stub Tuner for the Antenna Impedance Matching for High-Power RF Plasma Experiments
Document Type
Periodical
Source
IEEE Transactions on Plasma Science IEEE Trans. Plasma Sci. Plasma Science, IEEE Transactions on. 52(2):521-526 Feb, 2024
Subject
Engineered Materials, Dielectrics and Plasmas
Fields, Waves and Electromagnetics
Liquids
Impedance
Radio frequency
Tuners
Power transmission lines
Plasmas
Tokamak devices
Impedance matching
liquid stub
RF plasma experiment
single-stub matching
steady-state superconducting tokamak (SST-1)
tokamak
Language
ISSN
0093-3813
1939-9375
Abstract
A 1–5/8” liquid stub tuner (LST) with effective impedance matching for ion cyclotron RF signal transmission is presented. The main objective is to maximize the power transmission from RF source to antenna for Steady-State Superconducting and Aditya Tokamaks. The design and characterization of an LST for varying susceptance from 10 to 100 MHz are described here. The difference in the dielectric constants of air and liquid makes the wavelengths different in these two mediums. This difference in wavelengths of RF waves is utilized for changing the impedance of LST. The LST’s experimental susceptance is confirmed by CST simulation and MATLAB analysis. The single-stub matching mechanism is implemented using the validated approach. The theoretical research indicates the LST’s mechanical benefits over traditional ones. Instead of finger contact-based sliding mechanics, the LST uses liquid height movement. It avoids sparks from high-current finger connections in traditional air dielectric stub tuners’ moving plungers. This idea for impedance matching overcomes the constraints of traditional stub tuners where spark gets developed between moving plunger and coaxial conductors.