PFC Current shaping

摘要

A PFC circuit according to the invention is connected to a grid, includes an input filter and a rectifier connected to a converter. A control circuit generates the reference current for the current regulator of the converter that controls its input current. Thereby, the reference current is generated by adding an offset current (I0) to a standard reference current and adapting the magnitude of the standard reference current to compensate for a change of the input power resulting from the addition of the offset current (I0). However, due to the addition of the offset current (I0) the magnitudes of some lower harmonic components of the input current of the power supply unit are increased and the magnitudes of some higher harmonic components of the input current are decreased such that the power supply may draw more current from the grid.

主权项

1. Method for generating a reference signal Iref for a current regulator of a PFC circuit of a power supply unit, characterised in that the reference signal is generated such that a magnitude of a lower harmonic component of an input current of the power supply unit is increased and a magnitude of a higher harmonic component of the input current is decreased.