How to design a unity power factor AC-DC Converter

[satyakumar]

Hi,
Is it possible to design unity power factor AC-DC power converter

 

[leotim]

It is very difficult to design a converter with PF exactly equals to 1, but you can design a AC-DC converter with power factors a little less that one, e.g. PF = 0.98.

To design such converter, you must use a PFC (power factor correction) unit in the first stage of your converter:

AC line ---------> PFC-------------> converter

Please give more detail information about the converter you need:
Input AC voltage:?
Output DC Voltage:?
Output Power:?

 

[sivakumar_tumma]

Yes it is possible to convert ..... but not exactly unity little less than unity....

some ships ara vailable at fairchild semiconductors . for eg: ML4821 chip can be used for building teh unity pf ac to dc converter...

 

[som_raparty]

i dotn think we can attain the unity power factor
as there will be tolerances in the componenets used
but you can achieve a little less then unity almost .98 and .99
i am using a pfc ic of texas make ucc2818d
and a lot of ics are available
but you should use it after the bridge as the first stage

bye
som

 

[max0412]

For your first attempt at this I would recommend the UC3854. There are lots of application examples for this IC and other info on the net.

https://focus.ti.com/docs/prod/folders/print/uc3854.html