• Bai, J.N.; Aulenbacher, K.; Diefenbach, J.; Echevarria, P.; Fichtner, F.; Heine, R.G.: MESA - Status of the Implementation of the MicroTCA.4-based LLRF Control System. In: Guoxi Pei ... [Ed.] : LINAC2018, Proceedings of the 29th Linear Accelerator Conference, Beijing, China, 16–21 September 2018Geneva: JACoW, 2018. - ISBN 978-3-95450-194-6, p. THPO007/691-694
    http://jacow.org/linac2018/papers/thpo007.pdf

Open Access Version

Abstract:
MESA at the Institut für Kernphysik (KPH) at Johannes Gutenberg-Universität Mainz is a multi-turn energy recovery linac (ERL), aiming to serve as user facility for particle physics experiments. The RF-accelerating systems of MESA consist of four 9-cell TESLA superconducting cavities, four normal conducting (NC) pre-accelerator cavities, two NC buncher cavities and two NC chopper cavities. They operate in continuous wave (CW) mode. In order to control the radio frequency (RF) amplitude and phase within the 12 cavities with the required accuracy and stability in the range of better than 0.01% and 0.01°, the MicroTCA.4 based digital low-level RF (LLRF) control system based on the development at DESY, Hamburg will be well adapted for the MESA cavities. In this paper, we describe the theoretical modelling of superconducting cavity and PID controller in SIMULINK which is useful to find the suitable control parameter for the PID controller and to predict the system performance. The progress to date of the implementation and tests of the LLRF system at MESA will also be presented.