The BTF (Beam Transfer Facility) DC/Pulsed 50 kW Power Supply for DAFNE injector

CERN has designed and built a special power supply for the INFN National laboratory of Frascati. This power supply is used to deflect the particle pulses coming from the Linac, which would normally go and fill the DAFNE collider, from the beam transfer line. The Linac repetition time is 20 ms, thus the power supply feeding the switchyard magnet must be able to ramp up and down in less than 20 ms and have a minimum ON flat top of 5 ms. In pulsed mode the flat top can be stretched to 0.96 s to allow a multi-pulse extraction. In addition this power supply must be able to operate as a conventional DC current generator. Finally as the Linac can produce both electrons and positrons it must be possible to reverse the polarity of the magnetic field, i.e. of the current.This paper describes the design and the commissioning of this power supply which was done by the CERN team.