SME 5307 S power converter J M CRAVERO

SME 5307 S power converter J. M. CRAVERO 10/17/2021

SME 5307 S power converter SME 5307 S ‘old converter’ • P 4 KV converter: capacitor discharge power converter with flat-top (active filter). • From EPC archives… I found the values of the capacitor bank and load with transfo n=10. • The magnet current waveform should have been like below (up to 3500 A) but with a flat-top. 10/17/2021

SME 5307 S power converter SME 5307 S ‘new converter’ • Installed in 2009 -2010 shutdown by Gilles Simonet (retired) because the ‘old converter’ was not able to operate at low current (? ). • Maxidiscap power converter with transfo n=10. • Operating current is 640 A… and the nominal current of the converter is 3500 A. 10/17/2021

SME 5307 S power converter 2015: increase of the current rise time • In 2015, we have increased the current rise time to reduce the supposed effect of the Eddy currents in the magnet. Beam is at the end of the flat-top Im=640 A Before After 10/17/2021

SME 5307 S power converter 2016/2017: reduction of the magnet current transients at turn-on • In 2017, we have minimized the oscillations on the magnet current (start of the current pulse) by installing a RLC filter and modifying the IGBT drivers to increase turn-on time. Im=640 A – zoom on the trigger of the pulse – reduction by a factor 4 of the oscillations Before After Magnet current (Light Blue) 10/17/2021