Enhanced pressure control system for the vacuum vessel of Damavand Tokamak using PID and multiple model control

This paper presents the implementation of the pressure control system for the vacuum vessel of Damavand Tokamak. PID controllers within the framework of multiple-model control are utilized for controller design, aiming to safely achieve the desired setpoint for the pressure of the vacuum vessel. The chamber pressure is measured in real-time using a Cold Cathode Pirani gauge and transferred as feedback to the controller. There is a gas injection system to adjust the chamber pressure. Multiple process models are derived for the vacuum vessel pressure based on a system identification approach using the experimental data from the process. The derived models are employed in designing the PID controllers. The designed controllers are implemented on the tokamak gas injection system. The experimental results demonstrate that the designed controllers effectively track the desired pressure profile.