Passive power factor correction incorporating AC/DC conversion

摘要

A passive power factor correction (PFC) circuit is disclosed. It converts an AC input voltage into at least one DC output voltage. A diode bridge and a diode pair rectify the AC input voltage and provide first and second rectified voltages, respectively. A resistor applies the second rectified voltage to a first capacitor that stores the first voltage. A diode applies the first voltage to an inductor. The inductor applies the first rectified voltage to an output capacitor that stores the DC output voltage. The passive PFC circuit is intended to expand commonly used full-wave bridge rectifier and following storage capacitor. It can replace an input circuit, including low pass filter, in many applications even if improved power factor is not required. The passive PFC specifically targets size of the inductor while avoiding any switching, and maintaining power factor that challenges active PFC circuits. Early prototypes reached power factor of 0.99 while driving a 100 W load.

主权项

1. A power factor correction circuit for converting an alternating current (AC) input voltage into at least one direct current (DC) output voltage, the power factor correction circuit comprising:
a first rectifying means for rectifying the AC input voltage and providing a first rectified voltage, wherein the first rectifying means comprises a first full bridge rectifier; a first capacitive means for storing a first voltage; a second capacitive means for storing the at least one DC output voltage; an inductive means for applying the rectified voltage to the second capacitive means; and a second rectifying means for applying the first voltage to the inductive means; and a third rectifying means wherein the third rectifying means comprises a second bridge rectifier for rectifying the AC input voltage and providing a second rectified voltage, wherein the second bridge rectifier comprises at least one component of the first full bridge rectifier; and a resistive means for applying the second rectified voltage to the first capacitive means.