Patent ID: 8102160

Claim:
A power factor improving apparatus comprising: an input unit which receives an input power which is an AC voltage; a power factor correction unit which generates a switching control signal and corrects a power factor of the input power received by the input unit based on the switching control signal; a power supply unit which generates a DC voltage from the input power and provides the DC voltage to the power factor correction unit to generate the switching control signal, wherein the power supply unit is configured such that, even when the input power is not received by the input unit, the DC voltage is transferred to the power factor correction unit to generate the switching control signal unless the DC voltage falls below a threshold; and a saturation prevention unit which controls the power factor correction unit such that the power factor correction unit does not exceed a limit, wherein the saturation prevention unit comprises: an input detector which detects whether the input power is received by the input unit; and a controller which blocks the DC voltage from the power supply unit to the power factor correction unit if the input detector detects that the input power is not received by the input unit, and wherein the controller controls the power factor correction unit to operate if the input detector detects the input power is received.