Designing a Sine‐Coil for Measurement of Plasma Displacements in IR‐T1 Tokamak

A method for the measurement of the plasma position in the IR‐T1 tokamak in toroidal coordinates is developed. A sine‐coil, which is a Rogowski coil with a variable wiring density is designed and fabricated for this purpose. An analytic solution of the Biot‐Savart law, which is used to calculate magnetic fields created by toroidal plasma current, is presented. Results of calculations are compared with the experimental data obtained in no‐plasma shots with a toroidal current‐carrying coil positioned inside the vessel to simulate the plasma movements. The results are shown a good linear behavior of plasma position measurements. The error is less than 2.5% and it is compared with other methods of measurements of the plasma position. This method will be used in the feedback position control system and tests of feedback controller parameters are ongoing.