Measurment of plasma displacements by a designed sine-coil and Mirnov coils in the 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 array of Mirnov coils employed for measurement of plasma position. 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 in both techniques. This method used in the feedback position control system and has been tested in feedback controller.