Design of a Robust $H_{\infty}$ Plasma Position Controller for Aditya-U Tokamak

In the Aditya-U Tokamak, the position and shape of the plasma are controlled based on measurements of the toroidal and poloidal magnetic fields. The objective is to maintain the plasma at the equilibrium position, or the center of magnetic confinement, to prevent contact with the surrounding vacuum vessel of the Tokamak. The traditional Proportional-Integral-Derivative (PID) controller may not be a suitable choice for handling uncertainties and disturbances in the system. Therefore, a <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">$H_{\infty}$</tex> controller is proposed in this paper for controlling the plasma position in the Aditya-U Tokamak. The aim is to regulate the plasma position by managing the Fast Feedback Power Supply (FFPS) input to the system. The controller generates the control signal for the Fast Feedback Power Supply (FFPS) to produce an appropriate magnetic field that stabilizes the plasma position. The simulation results obtained with the <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">$H_{\infty}$</tex> controller are compared with the responses of the traditional Proportional-Integral-Derivative (PID) controller. The robustness of the proposed <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">$H_{\infty}$</tex> controller is verified through simulation after introducing an external sinusoidal disturbance into the system. The response exhibits superior performance compared to the traditional Proportional-Integral-Derivative (PID) controller.