Why do power supplies require power factor correction?
First, power factor correction is required for CE marking as an indication of compliance with EN61000-3-2. Second, the label “power factor correction” I somewhat misleading, as the goal of the standard is to minimize the injection of harmful harmonic “noise” onto the control and power circuits connected to the power supply. To accomplish this, power supply manufacturers include a filtering circuit in the unit design. Some manufacturers employ passive filtering designs which provide minimal reduction of the harmonics. Micron employs an active filtering design which provides superior filtering results.
