Shape control with the XSC during plasma current ramp-up and ramp-down at the JET tokamak

The eXtreme Shape Controller (XSC) has been originally designed to control the plasma shape at JET during the flat-top phase, when the plasma current has a constant value. During the JET 2012 experimental campaigns, the XSC has been used to improve the shape control during the transient phases of plasma current ramp-up and ramp-down. In order to avoid the saturation of the actuators with these transient phases, a Current Limit Avoidance system (CLA) has been designed and implemented. This paper discusses the CLA algorithm and presents the experimental results achieved at JET during the 2012 campaigns using the XSC.

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