A new family of single-stage ripple-free input current ac-dc converters

In recent years, the single stage ac-dc converters with high power factor, low input current harmonics, low voltage stresses and tight output voltage regulation are very desirable to achieve low cost, high power density and high efficiency without violating the IEC 1000-3-2 standards. Although various innovative circuit technologies have been proposed, but the existing solutions usually suffer big EMI filter due to high input current ripple, particularly at higher output power level. Therefore, this paper introduces a new family of single stage ripple-free input current (S²RFIC) ac-dc converters to remove the EMI filter without penalizing the input current harmonics. The operation waveforms, steady state analysis and simulation results are given to confirm the new power processing at the primary side.