High-Precision Pattern Power Supply of Kicker Magnet for Multi-Beamline Operation at SACLA

At the Japanese XFEL facility SACLA, two XFEL beamlines (BL2 and BL3) has been switched by a kicker magnet. However, CSR effects at a dogleg beam transport to BL2 with a deflecting angle of 3 degrees limited the peak current of the electron beam. In order to cancel out the CSR effect, new beam optics is introduced for the dogleg. Here, a deflecting angle of the first kicker magnet is increased to 1.5 degree, which is three times larger than that of the previous one. To drive the kicker magnet, a high-power pattern power supply, which outputs the maximum power of 0.3 MW (299 A and 1 kV) with a stability of 10 ppm (peak-to-peak), has been developed using SiC MOSFETs as switching elements. This power supply can generate bipolar trapezoidal current waveforms at 60 Hz, and the amplitude and polarity of each waveform are controllable from pulse to pulse depending on a beam energy and a destination. Beam commissioning of the new beam switching system was started in February 2017. Through beam tunnig over one month we succeeded in the stable pulse-by-pulse operation of XFEL multi-beamlines with a nominal peak current of about 10 kA.