Patent ID: 8891261

Claim:
A low input-current-harmonic three-phase boost rectifier, comprising: an input stage for receiving a three-phase input voltage relative to a neutral node, the input stage comprising three terminals, each terminal being coupled to one of the three phases of the three-phase input voltage; an output stage adapted to couple to at least one load, the output stage comprising a plurality of serially connected output capacitors that are coupled between the neutral node and said load; one or more input capacitors each coupled between a terminal of said input stage and said neutral node; one or more switching converter stages, each switching converter comprising: two or more pluralities of serially-connected switches, each plurality of switches being coupled to said neutral node, at least one of the switches of said plurality of serially-connected switches operating at a variable frequency with a substantially 50% duty cycle and at least one of the switches of said plurality of serially-connected switches operating with a variable duty cycle that is less than or substantially equal to 50%; one or more clamping capacitors each coupled to a common node of the switches of said pluralities of serially-connected switches; one or more clamping diodes each clamping one of the common nodes to one of the voltages across the serially connected output capacitors; one or more boost inductors each coupled to one of the terminals of the input stage to receive a corresponding one of the phases of the three-phase input voltage; one or more input rectifier diodes each coupled between one of the boost inductors and a terminal of one of said pluralities of serially-connected switches; and one or more flying capacitors coupled across said pluralities of serially-connected switches; and one or more controllers adapted to vary at least one of (a) the switching frequency and (b) the duty cycle, based on at least one of: conditions at the load, the input voltage, and the output voltage; and one or more decoupling stages, each decoupling stage provided to be connected to a corresponding one of the converter stages and each decoupling stage comprising a primary inductive element and a secondary inductive element, such that the corresponding switching converter stage is connected across a terminal of the primary inductive element and a terminal of the secondary inductive element, so as to decouple the output stage from the corresponding switching converter stage.