ISOLATION OF SECONDARY TRANSFORMER WINDING CURRENT DURING AUXILIARY POWER SUPPLY GENERATION

摘要

An electronic system and method include a controller (206) to actively control power transfer from a primary winding (110) of a switching power converter to an auxiliary-winding (212) of an auxiliary power supply 214). The switching power converter is controlled and configured such that during transfer of power to the auxiliary-winding (212), the switching power converter does not transfer charge to one or more secondary-windings (116) of the switching power converter. Thus, the switching power converter isolates one or more secondary transformer winding currents (is) from an auxiliary-winding current. By isolating the charge delivered to the one or more secondary-windings (116) from charge delivered to the auxiliary-winding (212), the controller can accurately determine an amount of charge delivered to the secondary-windings (116) and, thus, to a load (108).