Online high voltage power supply ripple estimation and feedforward in LEDA

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 low level RF control system for LEDA. We propose an estimator of the ripple and its time derivative and a control law which is based on PID control and adaptive feedforward of estimated ripple. The control law reduces the effect of the deterministic cathode ripple that is due to high voltage power supply and achieves tracking of desired set points.