Hi all...
How boost converter s used for power factor correction after rectification...?? Could anybody here pls explain me ths concept.... am very mush confused.... after rectifying an ac supply to dc, how will the boost converter helps in correcting power factor...??

 

Correcting the power factor of what?

 

dolphi means power factor of a system; cosine of the angle between current and voltage.

 

dolphi means power factor of a system; cosine of the angle between current and voltage.

I know what is the definition of the power factor but the question is not clear, at least to me.

 

"Power factor" implies AC. "Rectification" and "boost converter" imply DC.

The question seems to be about rectified & filtered higher voltage lower current -vs- rectified & boosted lower voltage higher current. Is power factor of the primary different between these two. If so why?

 

I think the poster asked why boost converter is often used in PFC stage of a SMPS. It is a common design approach to use a first stage boost converter in a largish SMPS to improve the overall PF of the SMPS.