High power factor, voltage-doubler rectifier

A high power factor voltage-doubler rectifier for providing a dc output voltage, comprising:

• a rectifier including two pairs of series-connected diodes in a full-bridge configuration for providing a rectified ac voltage when coupled to an ac power line, said rectifier having a cathode and an anode;
• dc-to-dc converter means coupled between said dc output voltage and a common potential, said dc-to-dc converter means having first and second output boost circuits inductively coupled thereto, said first output boost circuit being coupled in series between the cathode of said rectifier and said dc output voltage, and said second output boost circuit being coupled in series, with a polarity opposite to that of said first output boost circuit, between the anode of said rectifier and said common potential;
• a pair of filter capacitors connected in series with a junction therebetween, the series combination of said filter capacitors being coupled between said dc output voltage and said common potential;
• and
• switch means coupled between the junction joining the diodes of one of said two pairs and the junction joining said filter capacitors, said switch means being closed to enable operation in a voltage-doubling mode for relatively low input ac line voltages, and said switch means being open to enable operation in a low boost mode for relatively high input ac line voltages, said output dc voltage being maintained in substantially the same range in both said modes of operation.