THREE-PHASE POWER-FACTOR CORRECTING AC-DC SELF-BALANCING RECTIFIER WITHOUT NEUTRAL CONNECTION

摘要

A three-phase non-isolated AC to DC rectifier operable without connection to a neutral of a three-phase AC supply is disclosed. The rectifier combines three single-phase symmetrical AC-DC boost converters connected in parallel at their mid-points and outputs. The boost converters are controlled such that each converter presents an input resistance of equal value to the AC supply. Doing this produces a stable star-point at the AC input and a stable mid-point at the DC output, whereby the DC output voltages remain balanced around a mid-point voltage without additional balancing circuitry.