Feedback stabilization of RWM with in-vessel coils

Active control of the resistive wall modes (RWMs) is analysed for the feedback system with internal correction coils (ICs). The analysis is performed using a single mode thin-wall model in the cylindrical approximation and proportional control. Three cases are considered: with radial field sensors, poloidal field sensors inside the vessel and poloidal sensors outside. It is shown that, within the model, the systems with such sensors and proportional feedback have similar characteristics. The feedback systems with internal and external correction coils are compared and advantages of the IC system are shown.