MicroTCA.4-Based Low-Level RF for Continuous Wave Mode Operation at the ELBE Accelerator

Abstract

At the ELBE Center for High-Power Radiation Sources, electrons are accelerated to an energy of up to 40 in a superconducting linear accelerator that is operated in continuous wave mode. The acceleration is achieved using superconducting RF cavities, which are driven by an analogue low level RF system and solid-state based RF amplifiers. The analogue low level RF system was transformed to a digital system based on the MicroTCA standard. It is in user operation since 2020. Here the new digital system and its integration in the ELBE control system is described. Furthermore, the system is characterised by noise measurements and shows RMS field stability of the digital low level RF system of 0.01° in phase and 0.005% in amplitude. In addition, an algorithm for compensating long term drifts is presented and characterised.