Isolated boost flyback power converter

摘要

An isolated boost power converter comprises a magnetically permeable multi-legged core (102) comprising first and second outer legs (132; 136) and a center leg (134) having an air gap (138) arranged therein. A boost inductor (Lboost) is wound around the center leg (134) or the first and second outer legs (132; 136) of the magnetically permeable multi-legged core (102). The boost inductor (Lboost) is electrically coupled between an input terminal (104) of the boost converter and a transistor driver (106) to be alternatingly charged and discharged with magnetic energy. A first and second series connected secondary transformer windings (SW1; SW2) with a center-tap (116) arranged in-between are wound around the first and second outer legs (132; 136), respectively, of the magnetically permeable multi-legged core (102). In a first discharge state, the magnetic energy stored in the boost inductor (Lboost) is discharged by directing a discharge current from the boost inductor through a primary transformer winding (PW1; PW2) and in a second discharge state, the magnetic energy stored in the boost inductor (Lboost) is discharged by discharging a magnetic flux through the first and second secondary transformer windings (SW1; SW2).

主权项

1. An isolated boost power converter, comprising:
a magnetically permeable multi-legged core comprising first and second outer legs and a center leg having an air gap arranged therein; an input terminal for receipt of an input voltage, Vin; a boost inductor being wound around the center leg or the first and second outer legs of the magnetically permeable multi-legged core; the boost inductor being electrically coupled between the input terminal and a driver to be alternatingly charged and discharged with magnetic energy; the driver having a driver output coupled to a primary transformer winding wound around the first and second outer legs of the magnetically permeable transformer core; the driver being configured to apply a primary voltage to the primary transformer winding in accordance with a driver control signal; first and second series connected secondary transformer windings with a center-tap arranged in-between and wound around the first and second outer legs; respectively, of the magnetically permeable multi-legged core; and a rectification circuit electrically coupled to respective outputs of the first and second secondary transformer windings to provide a rectified converter output voltage, Vout; wherein
in a first discharge state, the magnetic energy stored in the boost inductor is discharged by directing a discharge current from the boost inductor through the primary transformer winding; and in a second discharge state, the magnetic energy stored in the boost inductor is discharged by discharging a magnetic flux through the first and second secondary transformer windings.