The RF system test of the Xi'an 200 MeV proton application facility injector

The Xi'an 200 MeV proton application facility (XiPAF) injector consists of a RFQ and an IHDTL. The RF system works at 325 MHz with pulse mode. Two tetrodes are adopted as the last stage amplifiers, each can output 500 kW peak power. There are the solid state drive stage amplifier, the low level RF control system (LLRF), the monitoring system and the microwave transport line in the RF system as well. The RF system test has been carried out including the DC high voltage and RF conditioning of tetrodes, the RF conditioning of the RFQ and the IHDTL, debugging of the LLRF and the monitoring system. The result of the test meets the requirement of the injector designing. In specific, the system can work continuously for 8 hours in a stable state with 500 kW peak output via each tetrode, 150 μs pulse width and 1 Hz repetition rate. The LLRF can achieve ± 1% amplitude stability and ± 1° phase stability with closed loop. In addition, the system remote control is accomplished with the experimental physics and industrial control system (EPICS). (authors)