Fuzzy-logic-based plasma-position controller for STOR-M

The successful operation of a tokamak fusion reactor rests on its ability to stably confine a very hot plasma. The quality of the discharge in the Saskatchewan TORus-Modified (STOR-M) tokamak is strongly related to the position of the plasma column within the discharge vessel. If the plasma column approaches too near the wall, then either minor or complete disruption occurs. Consequently it is necessary to be able to control dynamically the position of the plasma column throughout the entire discharge. A fuzzy-logic-based controller was designed and implemented for this purpose. This controller was evaluated on the STOR-M tokamak during actual operation, and was found to provide reliably a high quality of control. The actual performance of the fuzzy-logic-based controller at actually controlling the position of the plasma column within the STOR-M tokamak is evaluated against the actual performance of a proportional-integral-derivative (PID) controller.