Stabilization of unstable vertical position of plasma in T-15 tokamak. II

Hierarchical Cascade Control Systems for Time-Dependent Dynamical Plants as Applied to Magnetic Plasma Control in D-Shaped Tokamaks

“…The T-15MD poloidal system [22] is copied from ITER and has three CS sections and six PF coils. By placing the PF-coils between the TF coil and the vacuum vessel to stabilize the vertical position of the plasma, it was possible to correct the error of the poloidal system copied from ITER [23][24][25] and get rid of the internal instability of the plasma vertical position control system.…”

“…In the ASDEX Upgrade the stabilization of the vertical position of the plasma is achieved by placing the PF coils of the horizontal field between the vessel and the TF-coil, and in the Globus-M2 Tokamak, through 4 HFC coils inside the TF-coil. The same design of plasma poloidal system regarding plasma vertical stabilization as in ASDEX Upgrade has been conducted in T-15MD [24,25]; (4) The most advanced poloidal systems are used in SPARC (Figure 5b), IGNITOR (Figure 6a), and TCV (Figure 4a) because they contain poloidal field coils in sufficiently large numbers and are located fairly evenly around the D-shaped vacuum vessel [18]. The fact is that plasma in a Tokamak (gas in a closed volume) is a plant under control with distributed parameters, so it is best to use a controller with distributed parameters to control it most effectively.…”