POWER FACTOR CORRECTION CIRCUIT, POWER FACTOR CORRECTION ASSEMBLY AND ON-LINE UNINTERRUPTIBLE POWER SUPPLY COMPRISING SAME

The present invention provides a power factor correction circuit (), a power factor correction assembly () and an on-line uninterruptible power supply including the same. The power factor correction circuit () comprises a pulse width modulated rectifier () and an isolated DC-DC converter (), wherein an output of the pulse width modulated rectifier () is connected to an input of the isolated DC-DC converter (). The power factor correction assembly () comprises a plurality of power factor correction circuits () described above, wherein inputs of pulse width modulated rectifiers () in the plurality of power factor correction circuits () are connected in series, and outputs of isolated DC-DC converters () in the plurality of power factor correction circuits () are connected in parallel. The power factor correction assembly () of the present invention needs no line-frequency transformer and has the advantages of small size, low cost and improved operation reliability.