Development of precision high voltage CCPS for XFEL

From 2011, the Pohang Accelerator Laboratory (PAL) had started the 10 GeV PAL-XFEL project. The PAL-XFEL needs a highly stable electron beam. The very stable beam voltage of a klystron- modulator is essential to provide the stable acceleration field for an electron beam[1]. Thus, the modulator system for the XFEL requires less than 50 ppm PFN voltage stability. To get this high stability on the modulator system, the inverter type HVPS is a pivot component. The requested specification of the inverter power supply is being developed the 50 kV, 5 kJ/sec 1 sets and 30 kJ/sec 4 sets at the PAL. In this paper, we will discuss the development and the test results of the inverter power supply for pulse modulator system for obtaining machine stability.