EPICS-Based Software Development of a Low-level RF System for the PEFP 100-MeV Proton Accelerator

Since its launch in 2002, the Proton Engineering Frontier Project (PEEP) has been constructing a 100-MeV proton accelerator. The high-power radio-frequency (RF) signal should be delivered into the radio-frequency quadrupole (RFQ) cavities and drift-tube linac (DTL) tanks for stable and efficient acceleration of a proton beam. The RF amplitude and phase-stability requirements of the accelerating field of a low-level RF (LLRF) system are within +/- 1% and +/- 1 degrees, respectively. In order to achieve a better performance with specially developed software, we developed a remote control system for RF control with experimental physics and industrial control system (EPICS). The LLRF control system was developed with a versa-module eurocard (VME) single board computer (SBC) and a field-programmable gate array (FPGA) peripheral component interconnect (PCI) mezzanine card (PMC) extended board. The EPICS input output controller (IOC) was implemented with an embedded system that could make it easily accessible to operators when using the EPICS standard communication method. The LLRF IOC has been in use at the PEFP 20-MeV proton accelerator for five months. In this paper, the details of the implementation and the configurations will be described.