Patent ID: 7839664
Filing Date: 2010-11-23
Classification: H02M,Y02B,Y02P

Abstract:
1. An AC-DC power supply comprising: a 3-phase AC voltage source providing balanced 120° phase-shifted input voltage signals at a power line frequency; an active power-factor corrected (PFC) circuit associated with each phase, each PFC circuit receiving a respective AC input voltage signal of a respective phase and providing respective DC signal carrying a ripple voltage of a respective phase; a respective output filter circuit for attenuating said ripple voltage of said respective phase; an isolation circuit coupling said respective DC signal to each respective output filter and ripple voltage of said respective phase to provide a respective isolated DC output voltage; said output filters of each phase forming a stacked series connection, wherein each respective isolated DC output voltage are added together to form an output DC signal and each ripple of each respective phase are added together and cancelled such that said ripple voltage at the power line frequency is eliminated.