Quasi single-stage flyback PFC converter with low output voltage ripple

A quasi single-stage flyback PFC(Power Factor Correction) converter with low output voltage ripple is proposed,which consists of a DOFC(Dual-Output Flyback Converter) and a Buck converter with fast dynamic response. The Buck converter is powered by the auxiliary output of DOFC and its output is connected in series with the main output of DOFC as the power source of load. In order to achieve low output voltage ripple and fast dynamic response,the PFC function is realized by the DOFC and the 100 Hz voltage ripple of its main output is compensated by the Buck converter. The experimental results show that,at the same power factor value,the quasi single-stage flyback PFC converter,compared to the single-stage flyback PFC converter,has much lower output voltage ripple of double power frequency and much faster dynamic response;while it,compared to the two-stage flyback PFC converter,has similar dynamic response and higher efficiency.