Feedback linearization application for LLRF control system

The Low Energy Demonstration Accelerator (LEDA) being constructed at Los Alamos National Laboratory will serve as the prototype for the low energy section of acceleration production of tritium (APT) accelerator. This paper addresses the problem of the low-level RF (LLRF) control system for LEDA. We propose a control law which is based on exact feedback linearization coupled with gain scheduling which reduces the effect of the deterministic klystron cathode voltage ripple that is due to harmonics of the high voltage power supply and achieves tracking of desired set points. Also, we propose an estimator of the ripple and its time derivative and the estimates based feedback linearization controller.