Document Type : Original Article
Authors
1 School of Physics, Damghan University, Damghan, Semnan
2 School of Physics, Damghan University
3 Plasma Physics Research Center, Islamic Azad University, Science and Research Branch, Tehran, Iran
Abstract
Controlling tokamak plasmas is a complex process that is affected by structured uncertainties and unmodeled dynamics. To overcome these challenges and achieve a well-defined robust behavioral outcome, it is crucial to develop standard controllers. The decoupling control theory for Multiple-Input Multiple-Output (MIMO) processes is a powerful technique that allows the mitigation or elimination of undesirable cross-coupling terms in tokamaks, making it superior to the Single-Input Single-Output (SISO) control scheme. Our study proposes two types of controllers, PID-tuned and cascaded-robust controllers, that exploit decoupling and robustness for horizontal position and current control of plasma in IR-T1 tokamak. We compare the controllers through simulations and study the impact of changing the vertical field coil voltage on the cross-coupling of these two plasma parameters. The results demonstrate that the PID-tuned controller outperforms the robust controller in terms of meeting control requirements, disturbance rejection, reference value tracking, and disruption mitigation, especially in cross-coupling controls. Of course, the definitive confirmation requires experimental studies with more diverse conditions and, finally construction and operation of these controllers in tokamaks.
Keywords
Main Subjects
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