Real-Time Vertical Plasma Position Control Using the Heavy Ion Beam Diagnostic

A future thermonuclear fusion reactor relies on the real-time control of, among others, instabilities and plasma position. At the ISTTOK tokamak, a novel approach of a real-time diagnostic system to control the vertical plasma position (in a 100-μs closed-loop) was implemented by: 1) developing the heavy ion beam diagnostic (HIBD) to perform the position measurement and 2) combining data processing on a field-programmable gate array and Multithreaded Application Real-Time executor software framework. The results of this implementation have demonstrated the successful control of the plasma position using the HIBD. It was proven that the HIBD can be used to measure the ISTTOK vertical plasma position and to provide feedback in real time. In this paper, the overall implementation and integration is described and the experimental results are presented.